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Essentials of botany.
31924001756729Jj'itoNTisi-iBCis. Pine Sap (Monotropa Hypopitys), a Saprophyte.ESSENTIALS OF BOTANY
BY
JOSEPH Y. BEKGEN, A.M.
GINN & COMPANY
BOSTON ■ NEW YORK • CHICAGO • LONDON
LEntered at Stationers’ Hall
Copyright, 1896, 1901, 1908
By JOSEPH Y. BERGEN
ALL RIGHTS RESERVED
711.5
Cfre satftenaum JBrccffi
GINN & COMPANY • PRO-
PRIETORS • BOSTON • U.S.A.PREFACE
The favorable reception accorded to the author’s revised
Elements of Botany has led him to hope that a somewhat fuller
book along the same lines might find a place. Accordingly
the present work has been prepared especially for the use of
secondary schools which devote a year to botany. It will
also be found usable in schools which devote less than a year
to the subject, but which prefer to spend on the study of
spore-plants a considerable portion of the total time available
for the science.
Chapters i-xxi will be found essentially identical with the
first twenty-one chapters of the Elements. The matter in
Chapters xxin-xxvn relating to cryptogamic types has been
rewritten and much extended. While the number of forms
discussed is kept within moderate limits, it is believed that
enough types are treated and that the presentation is suffi-
ciently full to enable the pupil to realize that each of the
higher plants is descended from a series of lower ones. Much
detail in the discussion of plant evolution seems too difficult
for most secondary schools.
The experience of a decade has shown that the study of
ecology, except in the most elementary form, demands more
kinds of knowledge and a better matured judgment than the
beginner in botany can command. The teacher who wishes
to do more with the subject than is suggested in the present
book is referred to Part III of Bergen and Davis’ Laboratory
and Field Manual of Botany.
iiiIV
PREFACE
In deference to the wishes of many teachers, chapters on
Plant Breeding, on Useful Plants, and on Timber and Forestry
have been added. This matter may be used as a basis on which
to build further reading for brief essays. Or it may suggest
elementary investigations into the horticulture, the agricul-
ture, or the forest conditions of the student’s own neighbor-
hood. The study of useful plants and their products may be
taken up from Chapter xxx as the topics suggest themselves
in earlier portions of the text, i.e., seeds as food and medicine
in connection with Chapter u, and so on.
The author wishes to thank Dr. A. A. Lawson, now of the
University of Glasgow, Scotland, who read the manuscript of
Chapters xxii-xxvii, for many valuable suggestions. Thanks
are also due to Professor D. P. Penhallow of McGill Uni-
versity, Montreal, for suggestions on Chapter xxviii, and to
Dr. H. von Schrenk of St. Louis for aid on the chapter on
Forestry.
Grateful acknowledgments are due for the use of illustra-
tions copied for various figures as follows: I). H. Campbell,
208, 215 ; H. W. Conn, 170, 171, 175; W. G. Farlow, 160 ;
A. E. Frye, 232, 231; C. F. Hodge, 225; A. D. Hopkins, 237;
D. S. Jordan, 223; F. Both, 236; J. H. Schaffner, 208; H. J.
Webber, 224. Special mention should be made of the unpub-
lished yucca drawing by Mrs. Grace Johnson Yieh, loaned by
Professor William Trelease and used for Fig. 132. Some of the
cuts above mentioned have been re-drawn, others are printed
from the original wood engravings or zinc etchings.
A large proportion of the illustrations in Chapters xxiV-
xxx have been re-drawn for the present book from the most
authoritative sources by E. 1ST. Fischer, F. S. Mathews, and
C. H. L. Gebfert.
Cambridge, Massachusetts
J. Y. B.CONTENTS
CHAPTER I	PAGES
The Seed and its Germination ......	4-11
CHAPTER II
Storage of Food in tiie Seed .	.	12-21
CHAPTER III
Movements, Development, and Morphology op the Seed-
ling ...............................  22-29
CHAPTER IV
Roots ...........	30-42
CHAPTER V
Plant-Cells ; Some Functions of Cells in the Root .	.	43-48
CHAPTER VI
Stems........................................49-64
CHAPTER VH
Structure op the Stem........................65-75
CHAPTER VIII
Living Parts op the Stem; Work op	the	Stem	.	.	.	76-85
CHAPTER IX
Buds.........................................86-96
vVI
CONTENTS
CHAPTER X	pages
Leaves .... 		97-104
CHAPTER XI Ecology of Leaves ........	105-112
CHAPTER XII Ecology of Leaves (continued) . ....	113-126
CHAPTER XIII Minute Structure of Leaves ; Functions of Leaves .	127-142
CHAPTER XIV The Study of Typical Flowers		143-147
CHAPTER XV The Flower of the Higher Seed-Plants ....	148-158
CHAPTER XVI True Nature of Floral Organs; Details of their Struc- ture ; Fertilization ......	159-167
CHAPTER XVII Ecology of Flowers; Pollination .....	168-180
CHAPTER XVIII The Study of Typical Fruits ......	181-184
CHAPTER XIX The Fruit .... .....	185-190
CHAPTER XX Ecology of Fruits ; Dispersal of Fruits and Seeds	191-199
CHAPTER XXI
The Struggle for Existence and the Survival of the
Fittest ........................................... 200-206CONTENTS
vii
CHAPTER XXII The Classification of Plants ....		PAGES . 207-210
Characteristics of	CHAPTER XXIH Spore-Plants ....	. 211-214
The A lg®	CHAPTER XXIV	. 215-238
The Pungi	CHAPTER XXV	. 239-264
The Bp.yophytes	CHAPTER XXVI	. 265-279
The Ptekidophytes	CHAPTER XXVII	. 280-294
CHAPTER XXVIIILIST OF PLATES
Frontispiece. Pine sap, or false beech drops (Monotropa JJypop-
itys), a saprophytic seed-plant without chlorophyll, and with
scales instead of foliage leaves.
Facing page
Plate I. Aerial roots of a banyan tree. This tree, a species of
Ficus, usually begins its life as a seedling in the crown of a palm
tree. It soon sends slender roots to the earth, and as these
penetrate the soil the banyan grows rapidly and soon destroys
the palm. A banyan tree has been known to cover with its
columnar roots a diameter of three hundred feet and reach a
height of eighty feet in seventy-five years, from the seed .	.	30
Plate II. Cocoa palms, showing the nearly cylindrical form of the
stems, their unbranched mode of growth, and the leafy crown
at the summit of the stem.............................. 66
Plate III. Pollarded poplars, showing growth of slender twigs
from dormant or from adventitious buds ....	96
Plate IV. Japanese ivy, a tendril climber, showing an irregular
set of leaf-mosaics, each leaf arranged at the most advantageous
angle for the reception of sunlight.................... 106
Plate V. An opening in a tropical forest, showing dense vegeta-
tion due to heat and moisture. Aerial roots abound. The
forest floor in the foreground is covered with shade plants
whose broad leaves fully utilize the light supply .	.	. 114
Plate VI. A California desert with a tree yucca (Clistoyucca
arborescens) in the foreground. This is one of the most con-
spicuous xerophytes of the deserts of the extreme southwestern
United States.................................. .	.	.118
Plate VII. American mistletoe, parasitic on a cottonwood tree.
The photograph is taken in winter, so that all the foliage shown
is that of the parasite .....................................138
Plate VIII. American cypress (Taxodium), a hydrophyte. The
conical “cypress-knees” in the foreground are outgrowths from
the roots, supposed by some to absorb oxygen and convey it to
the submerged roots..........................................140
viiiLIST OF PLATES
IX
Facing page
Plate IX. Flower-clusters of dogwood (Cornusflorida), showing a
highly developed and conspicuous involucre, probably attractive
to pollinating insects........................................172
Plate X. Thistle fruits, adapted for dispersal by the wind .	.192
Plate XI. Tree ferns in Ceylon.....................................282
Plate XII. Improvement of corn. The upper picture shows the
effect of drying seed corn by artificial heat. The rows near
the middle grew from kiln-dried seed, the others from ordinary
seed. The lower picture shows the effect of cross-pollination
and of self-pollination on the growth of corn from the seed.
The two rows of spindling plants at the left grew from seed pro-
duced by self-pollination, the larger plants of the other rows
from seed produced by cross-pollination .	.	314
Plate XIII. Fruiting banana plants. The natural slitting of the
leaves by the wind serves to prevent them from being blown
away bodily during tropical storms...............................328
Plate XIV. Oak saplings springing from a stump. Oak, chestnut,
and many other hard-wood trees are most quickly replaced on
cut-over woodlands by allowing young trees to grow from the
stumps................................................................352ESSENTIALS OF BOTANY
INTRODUCTION
Botany is the science of plants. It considers them as
individuals, treating of their development, form, structure,
and functions, and also as dwellers in plant communities,
with complicated relations to each other and the world
about them. One important division of the science,
taxonomic botany, deals with plants as members of the
plant kingdom and discusses their kinship, tracing their
descent from remote common ancestors.
The study of botany may well begin with a rapid exam-
ination of one of the higher plants, to get an idea of its
parts and their connection. Later on, some or all of the
topics above suggested may be entered upon as fully as
can be done in the time available for the entire subject
of botany. Finally, a brief study may be undertaken of
some of the uses of plants to man, that is, of the rudiments
of economic botany.
The Nasturtium (Tropaeolum).1
.1. The Entire Plant. Dig up a plant so as to preserve most of the
larger roots and wash the earth from them. Note the three sets of
1 Any seed-plant of convenient size, with rather large and conspicuous
flowers, will answer for this study. Some of the most available types for use
at the beginning of the school year are Petunia, Ipomcea, Salvia, Pelargonium,
Impatiens, Mimulus, Linaria, Antirrhinum.
12
ESSENTIALS OF BOTANY
parts or organs — roots, stems, and leaves — which make up the main
bulk of what is known as the plant body.
Draw the plant body considerably reduced.
B.	Roots. Note the origin and connections of the roots and state
some of the main differences between roots and stems of this plant.
C.	Stem. Select a portion of the stem with at least two well-
grown leaves attached, and draw (reduced), showing how the leaf-
stalks are attached. Describe how the stem branches. Cut off a bit
and see whether it is solid or hollow. Split a small portion of it
through the center and see if the stem appears to be of the same
structure throughout and whether there is any bark or skin (epidermis)
covering the exterior.
D.	Leaves. Draw one of the largest leaves (reduced) and one or
two of the smallest leaves (natural size). Include in the drawing
the leaf-stalks. Describe how the leaf-stalk is attached to the expanded
portion or blade of the leaf. Note where the principal veins originate
and what course they take through the leaf-blade. Describe the
principal differences between the upper and the under surface of
the blade. If growing plants are at hand, try to make out how the
tall kind of nasturtium climbs, that is, by what means it attaches
itself to any convenient support. Study plants growing undisturbed
and see whether the leaves are arranged at any definite angle with
reference to the sun’s rays (Plate IV).
The vegetative organs of the plant body, that is, the
parts which it uses in the processes of life and growth,
are the roots, stems, and leaves. Their functions are dis-
cussed in detail in special chapters, but here it may be
stated that the roots serve to fasten the plant to the earth
and to absorb from the soil -water and dissolved materials
useful in the nutrition of the plant; that the stem con-
ducts water and plant foods and supports the leaves in
a suitable position to do their work; and that the leaves
perform most of the work of making plant food from the
raw materials (which are derived from the air and the soil),
and of respiration.INTRODUCTION
3
E.	The Flower. Note that the stem bears flowers at intervals.
Decide from what definite points they may arise. Make a reduced
drawing of a short piece of stem with a leaf and a, flower-stalk, bearing
a flower. Draw (natural size) a side view of a flower with a bit of
flower-stalk attached. Note that a spur extends backward from the
flower nearly parallel to its stalk. Look at the outside and the
inside of the flower to see how the rather leaf-like, brightecolored
parts of which its principal bulk is made up are arranged with refer-
ence to each other. The five outer leaves, taken together, are called
the calyx, and the five inner ones the corolla. Cut off the calyx
leaves nearly at their bases, pull off the spur and all the corolla
leaves, and draw the remaining organs more than natural size. Note
that there are eight curved stalks, each of which bears a knob at its
tip. These are called stamens. Decide whether all of the stamens
mature at the same time. W ithin these is n much shorter object,
divided at the tip into three portions. This is the pistil. See whether
the stamens and the pistil mature at the same time.
F.	The Fruit. Note that after the flowers wither all the parts
except the pistil gradually fall off, and that the lower portion of the
pistil finally develops into a green, three-lobed fruit. Cut across the
largest and ripest fruit that can be obtained and ascertain how many
seeds each lobe of the fruit contains.
The production of seed is the office of the flower, and
the use of seeds is to reproduce the plant, since each per-
fect seed can under favorable circumstances grow into an
individual like the parent plant. The formation of the
seed is due to the action of pollen, a substance produced by
the stamens. In some plants the pollen appears like fine
dust, but in the majority of showy flowers, as in the nas-
turtium, it is a sticky, yellow, brownish, or reddish powder.
The pollen acts in a very complicated way (Chapter xyi)
on the rudimentary seeds borne within the base of the
pistil, and causes them to develop into perfect seeds.CHAPTER I
THE SEED AND ITS GERMINATION
1.	Germination of the Squash Seed. — Soak some squash seeds in
tepid -water for twelve hours or more. Plant these about an inch
deep in damp sand or pine sawdust or peat-moss in a wooden box
which has had enough holes bored through the bottom so that it
will not hold water. Put the box in a warm place (not at any time
over 70° or 80° Fahrenheit),1 and cover it loosely with a board or a
pane of glass. Keep the sand or sawdust moist, but not wet, and the
seeds will germinate. As soon as any of the seeds, on being dug
up, are found to have burst open, sketch one in this condition,2 not-
ing the manner in which the outer seed-coat is split, and continue
to examine the seedlings at intervals of two days, until at least eight
stages in the growth of the plantlet have been noted.3
Observe particularly how the sand is pushed aside by the rise of
the young seedlings. Suggest some reason for the manner in which
the sand is penetrated by the rising stem.
2.	Examination of the Squash Seed.—Make a sketch of the dry
seed, natural size. Note the little scar at the pointed end of the
1	Here and elsewhere throughout the hook temperatures are expressed in
Fahrenheit degrees, since with us, unfortunately, the Centigrade scale is not
the familiar one outside of physical and chemical laboratories.
2	The student need not feel that he is expected to make finished drawings
to record what he sees, but some kind of careful sketch, if only the merest
outline, is indispensable. Practice and study of the illustrations hereafter
given will soon impart some facility even to those who have had little or no
instruction in drawing. Consult here Figs. 2, 6, and 9.
8 The class is not to wait for the completion of this work (which may, if
desirable, be done by each pupil at home), but is to proceed at once with the
examination of the squash seed, as directed in the following sections, and to
set some corn to sprouting, so that it may be studied at the same time with
the germinating squashes.
4THE SEED AND ITS GERMINATION
5
-cot
seed where the latter was attached to its place of growth in the
squash. Label this hilum. Note the little hole in the hilum; it is
the micropyle, seen most plainly in a soaked seed. (If there are two
depressions on the hilum, the deeper one is the micropyle.)
Describe the color and texture of the outer coating of the seed.
With a scalpel or a very sharp knife cut across near the middle a
seed that has been soaked in water for twenty-
four hours. Squeeze one of the portions, held
edgewise between the thumb and finger, in
such a way as to separate slightly the halves
into which the contents of the seed is naturally
divided. Examine with the magnifying glass
the section thus treated, make a sketch of it,
and label the shell or covering of the seed and
the kernel within this.
Taking another soaked seed, chip away the
white outer shell called the testa, and observe
the thin, greenish inner skin (Fig. 1, e), with
which the kernel of the seed is closely covered.1
Strip this off and sketch the uncovered ker-
nel or embryo. Note that at one end it tapers
to a point. This pointed portion, known as
the hypocotyl, will develop after the seed sprouts
into the stem of the plantlet, like that shown
at c in Fig. 9.
Split the halves of the kernel entirely apart
from each other, noticing that they are only
attached for a very little way next to the hypo-
cotyl, and observe the thickness of the halves
and the slight unevenness of the inner surfaces.
These halves are called seed-leaves ot cotyledons.
Have ready some seeds which have been soaked for twenty-four
hours and then left in a loosely covered jar on damp blotting paper
at a temperature of 70° or over until they have begun to sprout.
Split one of these seeds apart, separating the cotyledons, and
observe, at the junction of these, two very slender pointed objects,
the rudimentary leaves of the plumule or first bud.
1 See Sect. 15, page 13.
Fig. 1. Lengthwise
Section of a Squash
Seed. (Magnified
about two and a
half times.)
c, hypocotyl; cot, coty-
ledon; e, endosperm;
h,hilum; p, plumule;
t, testa.6
ESSENTIALS OF BOTANY
3. Examination of the Bean. — Study the seed, both dry and after
twelve hours’ soaking, in the same general way in which the squash
seed has just been examined.1
Notice the presence of a distinct plumule, consisting of a pair- of
rudimentary leaves between the cotyledons, just where they are
joined to the top of the hypocotyl. In
many seeds (as the pea) the plumule
does not show distinct leaves. But
in all cases the plumule contains the
s growing point, the tip of the stem from
which all the upward growth of the
plant is to proceed.
Make a sketch of these leaves as they
lie in place on one of the cotyledons
after the bean has been split open.
Note the cavity in each cotyledon
caused by the pressure of the plumule
and of the hypocotyl.2
4. Germination of the Grain of Corn.
— Soak some grains of corn and plant
them as directed in Sect. I.3
Make six or more sketches at various
stages to illustrate the growth of the
plumule and the formation of roots;
first a main root from the base of the
embryo, then others more slender -from
the same region, and later on still
Fig. 2. Young Seedling of others from points higher up on the
Windsor Bean.	stem. The student may be able to dis-
o, cotyledon; r, root; s, stem, cover what becomes of the large outer
1	The larger the variety of bean chosen, the easier it will be to see and
sketch the several parts. The large red kidney bean, the horticultural bean,
or the Lima bean will do well for this examination.
2	The teacher will find excellent sketches of most of the germinating
seeds described in the present chapter in Newell’s Outlines of Lessons in
Botany, Part I.
3	The pupil may economize space by planting the new seeds in boxes
from which part of the earlier planted seeds have been dug up for use in
sketching, etc.THE SEED AND ITS GERMINATION
7
part of the embryo. This is really the single cotyledon of the
corn (Fig. (3). It does not as a whole rise above ground, but most
of it remains in the buried grain and acts as a digesting and absorb-
ing organ through which the endosperm or food stored outside of the
embryo is transferred into the growing plant as fast as it can be
made liquid for that purpose.
5.	Conditions Requisite for Germination. — When we try
to enumerate the external conditions which may affect
germination, we find that the principal ones are heat,
moisture, and presence of air. A few simple experi-
ments will show what influence some of these condi-
tions exert.
6.	Temperature. — Common observation shows that a
moderate amount of warmth is necessary for the sprouting
of seeds. Every farmer or gardener knows that during a
cold spring many seeds, if planted, will rot in the ground.
But a somewhat exact experiment is necessary to show
what is the best temperature for seeds to grow in, and
whether variations in the temperature make more differ-
ence in the quickness with which they begin to germinate
or in the total per cent which finally succeed.
EXPERIMENT I
Relation of Temperature to Germination. — Prepare at least four
teacups or tumblers, each with vet soft paper packed in the bottom
to a depth of nearly an inch. Have a tightly fitting cover over
each. Put in each vessel the same number of soaked peas. Stand
the vessels with their contents in places where they will be exposed
to different, but fairly constant, temperatures, and observe the sev-
eral temperatures carefully with a thermometer. Take pains to
keep the tumblers in the warm places from drying out, so that their
contents will not be less moist than that of the others. The following8
ESSENTIALS OF BOTANY
series is merely suggested, — other values maybe found more con-
venient. Note the rate of germination in each place and record in
tabular form as follows.
No. of seeds sprouted in 24 hrs. 48 hrs. 72 hrs. 96 hrs. etc.
At 32°,	---- ------- ------- -------- -------
At 50°,	---- ------- ------------------------
At 70°,	---- ------- ------- -------- -------
At 90°,1	---- ------- ------- -------- -------
7. Moisture. — What was said in the preceding section
in regard to temperature applies also to the question of
the best conditions for germination as regards the supply
Fig. 3. Soaked Peas in Stoppered Bottle, ready for
Exhaustion of Air.
of moisture. The soil in which seeds grow out of doors
is always moist; most kinds germinate best in earth not
nearly saturated with moisture.
8. Relation of the Air Supply to Germination.— If we
wish to see how soaked seeds will behave with hardly any
air supply, it is necessary to place them in a bottle arranged
1 For the exact regulation of the temperatures a thermostat (see Appendix II)
is desirable. If one is available, a maximum temperature of 100° or over
should be tried.THE SEED AND ITS GERMINATION
9
as shown in Fig. 3, exhaust the air by connecting the.glass
tube with an air-pump, which is then pumped vigorously,
and seal the tube while the exhaustion is going on. The
sealing is best done by holding a Bunsen flame under the
middle of the horizontal part of the tube. A much easier
experiment, which is nearly as satisfactory, can, however,
be performed without the air-pump.
EXPERIMENT II
Will Seeds Germinate well without a Good Supply of Air? — Place
some soaked seeds on damp blotting paper in the bottom of a bottle,
using seeds enough to fill it three-quarters full, and close tightly with
a rubber stopper.
Place a few other seeds of the same kind in a second bottle;
cover loosely.
Place the bottles side by side so that they will have the same
conditions of light and heat. Watch for results and tabulate as in
previous experiments.
Most seeds will not germinate under water, but those of the
sunflower will do so, and therefore Exp. II may be varied in the
following manner.
Remove the shells carefully from a considerable number of sun-
flower seeds.1 Try to germinate one lot of these in water which has
been boiled in a flask to remove the air, and then cooled in the same
flask. Over the water, with the seeds in it, a layer of cotton-seed
oil about a half inch deep is poured, to keep the water from con-
tact with air. In this bottle then there will be only seeds and air-
free water. Try to germinate another lot of seeds in a bottle half
filled with ordinary water, also covered with cotton-seed oil. Results?
9. Germination involves Chemical Changes---------If a ther-
mometer is inserted into a jar of sprouting seeds, for
1 These are really fruits, but the distinction is not an important one at
this time.10
ESSENTIALS OF BOTANY
instance peas, in a room at the ordinary temperature, the
peas will be found to be warmer than the surrounding
air. This rise of temperature is at least partly due to
the absorption from the air of that substance in it which
supports the life of animals and maintains the burning
of fires, namely, oxygen.
The union of oxygen with substances with which it
can combine, that is with those which will burn, is called
oxidation. This kind of chemical change is universal in
plants and animals while they are in an active condition,
and the energy which they manifest in their growth and
movements is as directly the result of the oxidation going
on inside them as the energy of a steam engine is the
result of the burning of coal or other fuel under its boiler.
In the sprouting seed much of the energy produced by the
action of oxygen upon oxidizable portions of its contents
is expended in producing growth, but some of this energy
is wasted by being transformed into heat which escapes
into the surrounding soil. It is this escaping heat which
is detected by a thermometer thrust into a quantity of
germinating seeds.
EXPERIMENT III
Effect of Germinating Seeds upon the Surrounding Air. — IVhen
Exp. II has been finished, remove a little of the air from above the
peas in the first bottle. This can easily be done with a rubber bulb
attached to a short glass tube. Then bubble this air through some
clear, filtered limewater. Also blow the breath through some lime-
water by aid of a short glass tube. Explain any similarity in
results obtained. (Carbon dioxide turns limewater milky.) After-
wards insert into the air above the peas in the same bottle a lighted
pine splinter, and note the effect upon its flame.THE SEED AND ITS GERMINATION
11
10.	Other Proofs of Chemical Action. — Besides the proof
of chemical changes in germinating seeds just described,
there are other kinds of evidence to the same effect.
Malt, which is merely sprouted barley with its germi-
nation permanently stopped at the desired point by the
application of heat, tastes differently from the unsprouted
grain, and can be shown by chemical tests to have suffered
a variety of changes. If you can get unsprouted barley
and malt, taste both and see if j'ou can decide what sub-
stance is more abundant in the malt.
Germinating kernels of corn undergo great alterations
in their structure; the starch grains are gradually eaten
away until they are ragged and full of holes and finally
disappear.
11.	The Embryo and its Development. — The miniature
plant, as it exists ready formed and alive but inactive in
the seed, is called the embryo. In the seeds so far exam-
ined, practically the entire contents of the seed-coats
consist of the embryo, but this is not the case with the
great majority of seeds, as will be shown in the following
chapter.CHAPTER II
STORAGE OF FOOD IN THE SEED
12.	Food in the Embryo--Squash seeds are not much
used for human food, though both these and melon seeds
are occasionally eaten in parts of Europe; but beans and
peas are important articles of food. Whether the material
accumulated in the cotyledons is an aid to the growth of
the young plant may be learned from a simple experiment.
13.	Mutilated and Perfect Seedlings. — One of the best
ways in which to find out the importance and the special
use of any part of a plant is to remove the part in ques-
tion and see how the plant behaves afterward.
EXPERIMENT IV1
Are the Cotyledons of a Pea of any Use to the Seedling ? — Sprout
several peas on blotting paper. When the plumules appear, carefully
cut away the cotyledons from some of the seeds. Place on a perfo-
rated cork, as shown in Fig. 4, one or two seedlings from which the
cotyledons have been cut, and as many which have not been muti-
lated, and allow' the roots to extend into the water. Let them grow
for some days, or even weeks, and note results.
14 Storage of Food outside of the Embryo.—In very
many cases the cotyledons contain little food, but there is
a supply of it stored in the seed beside or around them
(Figs. 5 and 6).
1 May be a home experiment.
12STORAGE OF FOOD IN TIIE SEED
IB
15. Examination of the Four-o’clock Seed. —Examine the external
surface of a seed 1 2 of tire four-o’clock, and try the hardness of the
outer coat by cutting it
with a knife. From
seeds which have been
soaked in water at least
twenty-four hours peel
off the coatings and
sketch the kernel.
Make a cross-section of
one of the soaked seeds
which has not been
stripped of its coatings,
and sketch the section,
as seen with the mag-
nifying glass, to show
the parts, especially the
Fu,. 4. Germinating Peas, growing in Water, .	. , ,	, .
”	two cotyledons, lying
in close contact and
4. Germinating Peas, growing in Water,
one deprived of its Cotyledons.
encircling the white, starchy-looking endosperm."
The name endosperm is applied to food stored in parts of the seed
other than the embryo.3 With a mounted needle pick out the little
almost spherical mass of endosperm from inside the cotyledons of a
seed which has been deprived of its coats,
and sketch the embryo, noting how it is
curved so as to enclose the endosperm
almost completely.
16. Examination of the Kernel of Indian
Corn. — Soak some grains of large yellow
field corn4 for about three days.
1	Strictly speaking, a fruit.
2	Buckwheat furnishes another excellent
study in seeds with endosperm. Like that of
the four-o’clock, it is, strictly speaking, a fruit;
so also is a grain of corn.
3	Reserve food derived from the part of the ovule (nucellus) just outside
of the embryo sac (Fig. 121) is called perisperm.
* The varieties with long, flat kernels, raised in the Middle and Southern
States under the name of “ dent’corn,” are the best.
I	n
Fig. 5. Seeds with En-
dosperm, Longitudinal
Sections.
I, asparagus (magnified).
II, poppy (magnified).14
ESSENTIALS OF BOTANY
Sketch an unsoaked kernel so as to show the grooved side where
the germ lies. Observe how this groove has become partially filled
up in the soaked kernels.
Remove the thin, tough skin from one of the latter and notice its
transparency. This skin — the bran of unsifted corn meal—does
not exactly correspond to the testa and inner coat of ordinary seeds,
since the kernel of corn, like all other
grains (and like the seed of the four-
o’clock), represents not merely the seed,
but also the seed-vessel in which it was
formed and grew, and is therefore a
fruit.
Cut sections of the soaked kernels,
some transverse, some lengthwise and
parallel to the flat surfaces, some length-
wise and at right angles to the flat sur-
faces. Try the effect of staining some
of these sections with iodine solution.
Make a sketch of one section of each
of the three kinds, and label the dirty
white portion of cheesy consistency,
embryo; and the yellow portions and
those which are white and floury, endo-
sperm.
Chip off the endosperm from one
kernel so as to remove the embryo free
from other parts.1 Notice its form,
somewhat triangular in outline, sometimes nearly the shape of a
beechnut, in other specimens nearly like an almond.
Estimate what proportion of the entire bulk of the soaked kernel
is embryo.
Split the embryo lengthwise so as to show the slender, somewhat
conical plumule.2
1	The embryo may be removed with great ease from kernels of rather
mature green nu n. Boil the corn for about twenty minutes on the cob, then
pick the kernels off one by one with the point of a knife. They may be
preserved indefinitely in alcohol of 50% or 75%.
2	The teacher may well consult Figs. 56-6-1, inclusive, in Gray’s Structural
Botany.
Fig. 6. Lengthwise Section
of Grain of Corn. (Magni-
fied about three times.)
y, yellow, oily part of endo-
sperm; vi, white, starchy part
of endosperm; p, plumule;
s, the shield (cotyledon), in
contact with the endosperm
for absorption of food from
it; the primary root.STORAGE OF FOOD IN THE SEED
15
17.	Starch. — Most common seeds contain starch. Every
one knows something about the appearance of ordinary
commercial starch as used in the laundry and as sold for
food in packages of cornstarch. When pure it is charac-
terized not only by its lustre, but also by its peculiar
velvety feeling when rubbed between the fingers.
18.	The Starch Test. — It is not always easy to recog-
nize at sight the presence of starch as it occurs in seeds,
but it may be detected by a very simple chemical test,
namely, the addition of a solution of iodine.1
EXPERIMENT A'2
Examination of Familiar Seeds with Iodine. — Cut in two with a
sharp knife the seeds to he experimented on, then pour on each, drop
by drop, some of the iodine solution. Only a little is necessary;
sometimes the first drop is enough.
If starch is present, a blue color (sometimes almost black) will
appear. If no color is obtained in this way, boil the pulverized seeds
for a moment in a few drops of water, and try again.
Test in this manner corn, wheat (in the shape of flour), oats (in
oatmeal), barley, rice, buckwheat, flax, rye, sunflower, four-o'clock,
morning-glory, mustard seed, beans, peanuts. Brazil-nuts, hazelnuts,
and any other seeds that you can get. Report your results in tabu-
lar form as follows.
Mi ch Starch	Little Starch	No Starch
Color:blackish or	Color:pale blue or	Color:brown, orange,
dark blue	greenish	or yellowish
1 The tincture of iodine sold at the drug-stores will do, but the solution
prepared as directed in the Handbook answers better. This may be made up
in quantity and issued to the pupils in drachm vials, to be taken home and
used there if the experimenting must be done outside of the laboratory or the
schoolroom.	2 May be a home experiment.16
ESSENTIALS OF BOTANY
19.	Microscopical Examination of Starch.1—Examine starch in
water with a rather high power of the microscope (not less than 200
diameters).
Pulp scraped from a potato, that from a canna rootstock, wheat
flour, the finely powdered starch sold under the commercial name of
“ cornstarch ” for cooking, oatmeal, and buckwheat finely powdered
in a mortar, will furnish excellent examples of the shape and mark-
ings of starch grains. Sketch all of the
kinds examined, taking pains to bring out
the markings.2 Compare the sketches
with Figs. 7 and 8.
With a medicine-dropper or a very
small pipette run a drop of iodine solu-
tion under one edge of the cover-glass,
at the same time withdrawing a little
water from the margin opposite by touch-
ing to it a bit of blotting paper. Exam-
ine again and note the blue coloration of
the starch grains and the unstained or
yellow appearance of other substances
in the field. Cut very thin slices from
beans, peas, or kernels of corn; mount in water, stain as above
directed, and draw as seen under the microscope. Compare with
Figs. 7 and 8.3 Note the fact that the starch is not packed away in
the seeds in bulk, but that it is enclosed in little chambers or alls.
20.	Plant-Cells. — Almost all the parts of the higher
plants are built up of little separate portions called cells.
The cell is the unit of plant-structure, and bears something
Fig. 7. Canna Starch.
(Magnified 300 diameters.)
1	At this point the teacher should give a brief illustrated talk on the con-
struction and theory of the compound microscope.
2	The marking's will be seen more distinctly if care is taken not to admit
too much light to the object. Rotate the diaphragm beneath the stage of tire
microscope, or otherwise regulate the supply of light, until the opening is
found which gives the best effect.
3	The differentiation between the starch grains, the other cell-contents,
and the cell-walls will appear better in the drawings if the starch grains are
sketched with blue ink.STORAGE OF FOOD IN THE SEED
17
the same relation to the plant of which it is a part that
one cell of a honeycomb does to the whole comb. Cells
are of all shapes and sizes, from little spheres a ten-thou-
sandth of an inch or less in diameter to slender tubes,
such as fibers of cotton, several inches long. To get an
idea of the appearance of some rather large cells, scrape a
little pulp from a ripe, mealy apple, and examine it first
Fig. 8. Sect ion through Exterior Part of a Grain of Wheat.
o, cuticle or outer layer of bran; ep, epidermis; m, layer beneath epider-
mis; qu, sch, layers of hull next to seed-coats; hr, >/, seed-coats; Kl,
layer containing proteid grains; st} cells of the endosperm filled with
starch. (Greatly magnified.)
with a strong magnifying glass, then with a moderate
power of the compound microscope. To see how dead,
dry cell-walls with nothing inside them look, examine (as
before) a very thin slice of elder pith, sunflower pith, or
pith from a dead cornstalk. Look also at the figures in
Chapter vil of this book. Xotice that the simplest plants
(Chapter XXIII) consist of a single cell each. The study18
ESSENTIALS OF BOTANY
of the structure of plants is the study of the forms which
cells and groups of cells assume, and the study of plant physi-
ology is the study of what cells and cell combinations do.
21.	Absorption of Starch from the Cotyledons.—Examine -with
the microscope, using a medium power, soaked beans and the cotyle-
dons from seedlings that have been growing for three or four weeks.
Stain the sections with iodine solution, and notice how completely
the clusters of starch grains that filled most of the cells of the
unsprouted cotyledons have disappeared from the shriveled cotyle-
dons of the seedlings. A few grains may be left, but they have lost
their sharpness of outline.
22.	Oil. — The presence of oil in any considerable quan-
tity in seeds is not as general as is the presence of starch,
though in many common seeds there is a good deal of it.
Sometimes the oil is sufficiently abundant to make it
worth while to extract it by pressure, as is done with
flaxseed, cotton-seed, the seeds of some plants of the cress
family, the “ castor bean ” and other seeds.
23.	Dissolving Oil from Ground Seeds. — It is not easily
possible to show a class how oil is extracted from seeds
by pressure ; but there are several liquids which readily
dissolve oils and yet have no effect on starch and most
of the other constituents of seeds.
EXPERIMENT VI
Extraction of Oil by Ether or Benzine. — To a few ounces of ground
flaxseed add an equal volume of ether or benzine. Let it stand ten
or fifteen minutes and then filter. Let the liquid stand in a saucer
or evaporating dish in a good draught till it has lost the odor of the
ether or benzine.
Describe the oil which you have obtained.STORAGE OF FOOD IN THE SEED
19
Of what use would it have been to the plant ?
If the student wishes to perform this experiment at home for
himself, he should bear in mind the following.
Caution. — Never handle benzine or ether near a flame or stove.
A much simpler experiment to find oil in seeds may readily be
performed by the pupil at home. Put the material to be studied,
e.g., flaxseed meal, corn meal, wheat flour, cotton-seed meal, buck-
wheat flour, oatmeal, and so on, upon little labeled pieces of white
paper, one kind of flour or meal on each bit of paper. Place all the
papers, with their contents, on a perfectly clean plate, free from
cracks, or on a clean sheet of iron, and put this in an oven hot
enough nearly (but not quite) to scorch the paper. After half an
hour remove the plate from the oven, shake off the flour or meal
from each paper, and note the results, a more or less distinct grease
spot showing the presence of oil, or the absence of any stain showing
that there was little or no oil in the seed examined.
24. Albuminous Substances. — Albuminous substances
or proteids occur in all seeds, though often only in small
quantities. They have nearly the same chemical composi-
tion as white of egg and the curd of milk among animal
substances, and are essential to the plant, since the living
and growing parts of all plants contain large quantities of
proteid material.
Sometimes the albuminous constituents of the seed
occur in more or less regular grains (Fig. 8, Kl). But
much of the proteid material of seeds is not in any form
in which it can be recognized under the microscope.
One test for its presence is the peculiar smell which it
produces in burning. Hair, wool, feathers, leather, and
lean meat all produce a well-known sickening smell when
scorched or burned, and the similarity of the proteid
material in such seeds as the bean and pea to these sub-
stances is shown by the fact that scorching beans and
similar seeds give off the familiar smell of burnt feathers.20
ESSENTIALS OF BOTANY
25. Chemical Tests for Proteids. —All proteids (and very
few other substances) are turned yellow by nitric acid, and
this yellow color becomes deeper or even orange when the
yellowish substance is moistened with ammonia. They
are also turned yellow by iodine solution.
EXPERIMENT YII
Detection of Proteids in Seeds.—Extract the germs from some
soaked kernels of corn and bruise them; soak some wheat-germ meal
for a few hours in warm water, or wash the starch out of wheat-flour
dough; reserving the latter for use, place it in a white saucer or por-
celain evaporating dish and moisten well with nitric acid; examine
after fifteen minutes.
26. The Brazil-Nut as a Typical Oily Seed. — Not many
familiar seeds are as oily as the Brazil-nut. Its large size
makes it convenient for examination, and the fact that this
nut is good for human food makes it the more interesting
to investigate the kinds of plant-food which it contains.
EXPERIMENT VIII
Testing Brazil-Nuts for Plant-Foods. — Crack fifteen or twenty
Brazil-nuts, peel off the brown coating from the kernel of each, and
then grind the kernels to a pulp in a mortar. Shake up this pulp
with ether, pour upon a paper filter, and wash with ether until the
washings when evaporated are nearly free from oil. The funnel
containing the filter should be kept covered as much as possible
until the washing is finished. Evaporate the filtrate to procure the
oil, which may afterwards be kept in a glass-stoppered bottle. Dry
the powder which remains on the filter and keep it in a wide-
mouthed bottle. Test portions of this powder for proteids and for
starch. Explain the results obtained.STORAGE OF FOOD IN THE SEED
21
27. Other Constituents of Seeds. — Besides the substances
above suggested, others occur in different seeds. Some of
these are of use in feeding the seedling, others are of value
in protecting the seed itself from being eaten by animals
or in rendering it less liable to decay. In such seeds as
that of the nutmeg, the essential oil which gives it it s char-
acteristic flavor probably makes it unpalatable to animals
and at the same time preserves it from decay.
Date seeds are so hard and tough that they cannot be
eaten and do not readily decay. Lemon, orange, horse-
chestnut, and buckeye seeds are too bitter to be eaten,
and the seeds of the apple, cherry, peach, and plum are
somewhat bitter.
The seeds of larkspur, thorn-apple,1 croton, the castor-
oil plant, nux vomica, and many other kinds of plants
contain active poisons.
1 Datura, commonly called “ Jimson weed.”CHAPTER III
MOVEMENTS, DEVELOPMENT, AND MORPHOLOGY OF
THE SEEDLING
28. How the Seedling emerges. — As the student has
already learned by his own observations, the seedling
does not always push its way straight out of the ground.
Corn, like all the other grains and grasses, it is true, sends
a tightly rolled, pointed leaf vertically upward into the
air. But the other seedlings examined usually will not
be found to do anything of the sort. The squash seedling
is a good one in which to study what may be called the
arched hypocotyl type of germination. If the seed when
planted is laid horizontally on one of its broad surfaces, it
usually goes through some such changes of position as are
shown in Fig. 9.
The seed is gradually tilted until at the time of their
emergence from the ground the cotyledons are almost
vertical. The only part above the ground-line at this
period is the arched hypocotyl. Once out of ground, the
cotyledons soon rise until they are again vertical, but with
the ends farthest from the hypocotyl at the top. Then
the two cotyledons separate until they once more lie hori-
zontal, pointing away from each other.
Can you suggest any advantage which the plant derives
from having the cotyledons dragged out of the ground
rather than having them pushed out, tips first?
22MOVEMENTS OF THE SEEDLING
23
29. What pushes the Cotyledons up?—A very little
study of any set of squash seedlings is sufficient to show
that the portion of the plant where roots and hypocotyl
are joined'neither rises nor sinks, but that the plant grows
both ways from this part. It is evident that as soon as
the hypocotyl begins to lengthen much it must do one of
Fig. 9. Successive Stages in the Life History of the Bean Seedling.
A A, the surface of the ground; r, primary root; r', secondary root;
0, hypocotyl; a, arch of hypocotyl; co, cotyledons.
changes does the plantlet undergo in passing from the
stage shown at A to that of B and of C, making it harder
and harder for the root to be thrust downward ?
30. Use of the Peg. — Squash seedlings usually (though
not always) form a sort of knob on the hypocotyl. This24
ESSENTIALS OF BOTANY
is known as the peg. Study a good many seedlings and try
to find out what the lengthening of the hypocotyl, between
the peg and the bases of the cotyledons, does for the little
plant. Set a lot of squash seeds, hilum down, in moist
sand or sawdust and see whether the peg is more or less
developed than in seeds sprouted lying on their sides, and
whether the cotyledons in the case of the vertically planted
seeds usually come out of the ground in the same condi-
tion as do others.
31.	Disposition made of the Cotyledons. — The cotyledons
of the squash during the growth of the seedling increase
greatly in surface, acquire a green color and a generally
leaf-like appearance, and, in fact, do the work of ordinary
leaves. In such a case as this the appropriateness of the
name seed-leaf is evident enough,— one recognizes at sight
the fact that the cotyledons are actually the plant’s first
leaves. In the bean the leaf-like nature of the cotyledons
is not so clear. They rise out of the ground like the squash
cotyledons, but then gradually shrivel away, though they
may first turn green and somewhat leaf-like for a time.
The development of the plumule seems to depend some-
what on that of the cotyledons. The squash seed has coty-
ledons which are not too thick to become useful leaves,
and so the plant is in no special haste to get ready any
other leaves. The plumule, therefore, cannot readily be
found in the unsprouted seed, and is almost microscopic
in size at the time when the hypocotyl begins to show
outside of the seed-coats.
32.	Root, Stem, and Leaf. — By the time the seedling is
well out of the ground it usually possesses the three kinds
of vegetative organs, or parts essential to growth, of ordinary
flowering plants, i.e., the root, stem, and leaf, or, as theyDEVELOPMENT OF TIIE SEEDLING
25
are sometimes classified, root and shoot. All of these
organs may multiply and increase in size as the plant grows
older, and their mature structure will be studied in later
chapters, but some facts concerning them can best be
learned by watching their growth from the outset.
33. Elongation of the Root. — We know that the roots
of seedlings grow pretty rapidly from the fact that each
day finds them reaching visibly farther down into the water
or other medium in which they are planted. A sprouted
Windsor bean in a vertical thistle-tube will send its root
downward fast enough so that ten minutes’ watching
through the microscope will suffice to show growth. To
find out just where the growth goes on requires a special
experiffient.
EXPEPiIMEXT IX
In what Portions of the Root does its Increase in Length take place ?
— Sprout some peas on moist blotting paper in a loosely covered tum-
bler. 'When the roots are one and a half inches or more long, mark
them along the whole length with little dots made with a bristle
dipped in water-proof India ink, or a fine inked thread stretched on
a little bow of whalebone or brass wire.
Transfer the plants to moist blotting paper under a bell-glass or
an inverted battery jar and examine the roots at the end of twenty-
four- hours to see along what portions their length has increased;
continue observations on them for several days.
34. Root-Hairs. — Barley, oats, wheat, red clover, or
buckwheat seeds soaked and then sprouted on moist blot-
ting paper afford convenient material for studying root-
hairs. The seeds may be kept covered with a watch-glass
or a clock-glass while sprouting. After they have begun
to germinate well care must be taken not to have them26
ESSENTIALS OF BOTANY
kept in too moist an atmosphere, or very few root-hairs
will lie formed. Examine with the magnifying glass
those parts of the root which have these appendages.
Try to find out whether all the portions of the root are
equally covered with hairs, and, if not, where they are
most abundant (see also Fig. 10).
The root-hairs in plants growing under ordinary condi-
tions are surrounded by the moist soil and wrap them-
selves around microscopical particles of earth (Fig. 11).
Thus they are able to absorb rapidly through their thin
walls the soil-water with whatever mineral substances it
has dissolved in it.
35.	The Young Stem. — The hypocotyl, or portion of
the stem which lies below the cotyledons, is the -earliest
formed portion of the stem. Sometimes this lengthens but
little, as in Fig. 2 ; often, however, as the student knows
from his own observations, the hypocotyl lengthens enough
to raise the cotyledons well above ground, as in Fig. 9.
The later portions of the stem are considered to be
divided into successive nodes (places at which a leaf, or
a scale which represents a leaf, appears) and internodes
(portions between the leaves).
The student should watch the growth of a seedling bean
or pea and ascertain by actual measurements whether the
internodes lengthen after they have once been formed, and,
if so, for how long a time the increase continues.
36.	The First Leaves. — The cotyledons are, as already
explained, the first leaves which the seedling possesses, —
even if a plumule is found well developed in the seed, it
was formed after the cotyledons. In those plants which
have so much food stored in the cotyledons as to render
these unfit ever to become useful foliage leaves, there isMORPHOLOGY OF THE SEEDLING
27
little or nothing in the color, shape, or general appearance
of the cotyledon to make one think it really a leaf, and it
is only by studying many cases that the botanist is enabled
to class all cotyledons as leaves in their nature, even if they
are quite unable to do the ordinary work of leaves. The
Fig. 10.	Fig. 11.
Fig. 10. A Turnip Seedling, with the Cotyledons developed into
Temporary Leaves.
h, root-hairs from the primary root; 6, bare portion of the root on
which no hairs have as yet been produced.
Fig. 11. Cross-Section of a Root.
A good deal magnified, showing root-liairs attached to particles of
soil, and sometimes enwrapping these particles.
studj' of the various forms which the parts or organs of a
plant may assume is called morphology; it traces the rela-
tionship of parts which are really akin to each other,
though dissimilar in appearance and often in function.
In seeds which have endosperm, or other food outside
of the embryo, the cotyledons usually become green and28
ESSENTIALS OF BOTANY
leaf-like, as they do, for example, in the four-o’clock, the
morning-glory, and the buckwheat; but in the seeds of
the grains (which contain endosperm) a large portion of
the single cotyledon remains throughout as a thickish
mass buried in the seed. In a few cases, as in the pea,
there are scales instead of true leaves formed on the first
nodes above the cotyledons, and it is only at about the
third node above that leaves of the ordinary kind appear.
In the bean and some other plants which
co	r
in general bear one leaf at a node along
the stem there is a pair produced at the
first node above the cotyledons, and the
leaves of this pair differ in shape from
those which arise from the succeeding por-
tions of the stem.
37. Classification of Plants by the Number
of their Cotyledons. — In the pine family
the germinating seed often displays more
than two cotyledons, as shown in Fig. 12;
in the majority of common flowering plants
the seed contains two cotyledons, while in
the lilies, the rushes, the sedges, the grasses,
and some other plants there is but one cotyledon. Upon
these facts is based the division of most flowering plants
into two great groups : the dicotyledonous plants, which
have two seed-leaves, and the monocotyledonous plants,
which have one seed-leaf. Other important differences
nearly always accompany the difference in number of
cotyledons, as will be seen later.
Fig. 12. Germi-
nating Pine.
co, cotyledons.MORPHOLOGY OF THE SEEDLING
29
38. Tabular Review of Experiments. — Make out a table
containing a very brief summary of tbe experiments thus
far performed, as follows.
Number of Experiment	Object sought	Materials and Apparatus	Opera- tions PERFORMED	Results	Inferences
•					CHAPTER IV
ROOTS1
39.	Origin of Roots. — The primary root originates from
the lower end of the hypocotyl, as the student learned from
his own observations on sprouting seeds. The branches of
the primary root are called secondary roots, and the branches
of these are known as tertiary roots. Those roots which occur
on the stem or in other unusual places are known as adven-
titious roots. The roots which form so readily on cuttings of
willow, southernwood, tropseolum, French marigold, gera-
nium (pelargonium), tradescantia, and many other plants,
when placed in damp earth or water, are adventitious.
40.	Aerial Roots. — While the roots of most familiar
plants grow in the earth and are known as soil-roots, there
are others which are formed in the air, called aerial roots.
They serve various purposes : in some tropical air-plants
often cultivated they fasten the plant to the tree on which
it establishes itself, and they also take in water which
drips from branches and trunks above them, so that these
plants require no soil and grow in mid-air suspended from
trees, which serve them merely as supports ;2 many such
1	To the plant the root is more important than the stem. The author has,
however, treated the structure of the latter more fully than that of the root,
mainly because the tissues are more varied in the stem and a moderate knowl-
edge of.the more complex anatomy of the stem will serve every purpose.
2	If it can be conveniently managed, the class will find it highly interesting
and profitable to visit any greenhouse of considerable size in which the aerial
roots of orchids and aroids may be examined.Plate I. Aerial Roots of a Banyan Tree.ROOTS
31
air-plants are grown in greenhouses. In such plants as the
ivy (Fig. 13) the aerial roots (which are also adventitious)
hold the plant to the wall or other surface up which it climbs.
In the Indian corn roots are sent out from nodes at some
distance above the ground and finally descend until they
enter the ground. They serve botli to anchor the corn-
stalk so as to enable it to resist the wind and to supply
additional water to the plant.1 They often produce no
rootlets until they reach the ground.
41. Water-Roots. — Many plants, such as the willow,
readily adapt their roots to live either in earth or in water,
and some, like the little floating duckweed, regularly produce
1 Specimens of the lower part of the cornstalk, with ordinary roots and
aerial roots, should be dried and kept for class study.82
ESSENTIALS OF BOTANY
roots which are adapted to live in water only. These
water-roots often show large and distinct sheaths on the
ends of the roots, as, for instance, in the so-called water-
hyacinth. This plant is especially interesting for labora-
tory cultivation from the fact that it may readily be
transferred to moderately damp soil, and that the whole
plant presents curious modifications when made to grow
in earth instead of water.
42.	Parasitic Roots.1 — The dodder, the mistletoe, and a
good many other parasites live upon nourishment which
they steal from other plants called hosts. The parasitic roots,
or haustoria, form the most intimate connections with the
interior portions of the stem or the root, as the case may be,
of the host-plant on which the parasite fastens itself.
In the dodder, as is shown in Fig. 14, it is most inter-
esting to notice how admirably the seedling parasite is
adapted to the conditions under which it is to live. Rooted
at first in the ground, it develops a slender, leafless stem,
which, leaning this way and that, no sooner comes into
permanent contact with a congenial host than it produces
haustoria at many points, gives up further growth in its
soil-roots, and grows rapidly on the strength of the sup-
plies of ready-made sap which it obtains from the host.
43.	Forms of Roots. —The primary root is that which
proceeds like a downward prolongation directly from the
lower end of the hypocotyl. In many cases the mature root-
system of the plant contains one main root much larger than
any of its branches. This is called a taproot (Fig. 15).
Such a root, if much thickened, would assume the form
shown in the carrot, parsnip, beet, turnip, salsify, or radish,
and is called a fleshy root, Some plants produce multiple
1 See Kerner and Oliver’s Natural History of Plants, Vol. I, pp. 171-213.ROOTS
33
primary roots, that is, a cluster proceeding from the lower
end of the hypocotyl at the outset. If such roots become
thickened, like those of the sweet potato and the dahlia
(Fig. 17), they are known as fascicled roots.
ABC
Pig. 14. Dodder growing upon a Golden-Rod Stem.
s, seedling dodder plants, growing in earth; h> stem of host; r, haustoria
or parasitic roots of dodder; l, scale-like leaves; A, magnified section
of a portion of willow stem, showing penetration of haustoria.34
ESSENTIALS OF BOTANY
Roots of grass, etc., are thread-like, and known as
fibrous roots (Fig. 16).
44. General Structure of Roots. — The structure of the
very young root can be partially made out by examining
the entire root with a moderate magnifying power, since
the whole is sufficiently translucent to allow the interior
as well as the exterior portion to be studied while the root
is still alive and growing. Earth roots will not do for
this, since the adhering particles are opaque and hide
the structures beneath.
Place some vigorous cuttings of tradescantia or Zebrina, which
can usually be obtained of a gardener or florist, in a beaker or jar of
water.1 The jar should be as thin and transparent as possible, and
it is well to get a flat-sided rather than a cylindrical one. Leave
the jar of cuttings in a sunny, warm place. As soon as roots have
i It the tradescantia or Zebrina cannot be obtained, roots ot seedlings of
oats, wheat, or barley, or of red-clover seedlings raised in a large covered cell
on a microscope slide, may be used.ROOTS
35
developed at the nodes and reached the length of three-quarters of
an inch or more, arrange a microscope in a horizontal position (see
handbook) and examine the tip and adjacent portion of one of the
young roots with a power of from twelve to twenty diameters.
Note:
(a)	The root-cap, of loosely attached cells.
(b)	The central cylinder.
(c)	The cortical portion, a tubular part enclosing the solid
central cylinder.
(d)	The root-hairs, which cover some parts of the outer layer
of the cortical portion very thickly. Observe particularly
how far toward the tip of the root the root-hairs extend,
and where the youngest ones are found.
Make a drawing to illustrate all the points above suggested
(a, b, c, d). Compare your drawing with Fig. 18. Make a careful
study of longitudinal sections through the centers of the tips of very
young roots of the hyacinth or the Chinese sacred lily. Sketch one
section and compare the sketch with Fig. 18.
Make a study of the roots of any of the common duckweeds,
growing in a nutrient solution in a jar of water under a bell-glass, and
note the curious root-pockets which here take the place of root-caps.
45. Details of Root-Structure. — The plan on which the
young root is built has been outlined in Sect. 44. A few
further particulars are necessary to an understanding of
how the root does its work. On examining Fig. 19, the
cylinders of which the root is made up are easily dis-
tinguished, and the main constituent parts of each can be
made out without much trouble. The epidermis-cells are
seen to be somewhat brick-shaped, many of them provided
with extensions into root-hairs. Inside the epidermis lie
several layers of rather globular, thin-walled cells, and
inside these a boundary layer between the cortical or bark
portion of the root and the central cylinder. This latter
region is especially marked by the presence of certain
groups of cells, shown at w and d and at b, the two36
ESSENTIALS OF BOTANY
former serving as channels for air and water, the latter
(and w also) giving toughness to the root.
Roots of shrubs and trees more than a year old will be
Fig. 18. Lengthwise Section (somewhat dia-
grammatic) through lloot-Tip of Indian Corn,
x about 130.
w, root-cap; i, younger part of cap; dead cells
separating from cap; s, growing point; o, epi-
dermis ; p, intermediate layer between epidermis
and central cylinder; p, central cylinder; cl, layer
from which the root-cap originates.
found to have in-
creased in thickness
by the process
described in Sect.
88, and a section
may look quite un-
like the young root-
section shown in
Fig. 19.
46. Examination of
the Root of a Shrub or
Tree. — Cut thin trans-
verse sections of large
and small roots of any
hardwood tree* and
examine them first
with a low power of the
microscope, as a two-
inch objective, to get
the general disposition
of the parts, then with
a higher power, as the
half-inch or quarter-
inch, for details. With
the low power, note :
(a) The brown layer
of outer bark.
(J) The paler layer within this.
(c) The woody cylinder which forms the central portion of the root.
'Young suckers of cherry, apple, etc., which may be pulled up by the
roots, will afford excellent material.HOOTS
37
The distinction between (J) and (c) is more evident when the
section has been exposed to the air for a few minutes and changed
somewhat in color.
47. Structure and Contents of a Fleshy Root. — In some
fleshy roots, such as the beet, the morphology of the parts
is rather puzzling, since they form many layers of tissue
in a single season, showing on the cross-section of the root
a series of layers
which look a little
like the annual
rings of trees.
The structure of
the turnip, radish,
carrot, and parsnip
is simpler.
Cut a parsnip
across a good deal
below the middle, and
stand the cut end in
eosin solution for
twenty-four hours.
Then examine by
slicing off successive
portions from the
upper end. Sketch
some of the sections
thus made. Cut one
parsnip lengthwise
and sketch the section
obtained. In what portion of the root did the colored liquid rise
most readily? The ring of red marks the boundary between the
cortical portion and the central cylinder. To which does the main
bulk of the parsnip belong? Cut thin transverse sections from an
ink-stained parsnip and in those sections that show it, find out where
Fig. 19. Much Magnified Cross-Section of a
very Young Dicotyledonous Root.
h, root-hairs with adhering bits of sand; e, epi-
dermis ; s, thin-walled, nearly globular, cells of
hark; b, hard bast; c, cambium; v:, wood-cells;
d, ducts.38
ESSENTIALS OF BOTANY
the secondary roots arise. If possible, peel off the cortical portion
from one stained root and leave the central cylinder with the sec-
ondary roots attached. Stain one section with iodine and sketch it.
Where is the starch of this root mainly stored ?
Test some bits of parsnip for proteids by boiling them for a
minute or two with strong nitric acid.
What kind of plant-food does the taste of cooked parsnips show
them to contain ? [On no account taste the bits which have been
boiled in the poisonous nitric acid.]
48.	Storage in Other Roots. — The parsnip is by no
means a remarkable plant in its capacity for root-storage.
The roots of the yam and the sweet potato contain a good
deal of sugar and much more starch than is found in the
parsnip. Beet-roots contain so much sugar that a large part
of the sugar supply of Europe and an increasing portion
of our own supply is obtained from them. Oftentimes the
bulk of a fleshy root is exceedingly large as compared with
that of the parts of the plant above ground.
A good example of this occurs in a plant,1 related to the
morning-glory and the sweet potato, found in the south-
eastern United States, which has a root of forty or fifty
pounds weight.
Not infrequently roots have a bitter or nauseous taste,
as in the case of the chicory, the dandelion, and the
rhubarb, and a good many, like the monkshood, the yellow
jasmine, and the pinkroot, are poisonous. Can you give
any reason why the plant may be benefited by the dis-
gusting taste or poisonous nature of its roots?
49.	Use of the Food stored in Fleshy Roots. — The
parsnip, beet, carrot, and turnip are biennial plants; that
is, they do not produce seed until the second summer or
fall after they are planted.
1 Ipomcea Jalapa.BOOTS
39
The first season’s work consists mainly in producing the
food which is stored in the roots. To such storage is
due their characteristic fleshy appearance. If this root is
planted in the following spring, it feeds the rapidly grow-
ing stem which proceeds from the bud at its summit, and
an abundant crop of flowers and seed soon follows; while
the root, if examined in late summer, will be found to be
withered, with its store of reserve material quite exhausted.
The roots of the dahlia (Fig. 17), the sweet potato, and a
multitude of other perennials, or plants which live for many
years, contain much stored plant-food. Many such plants die
to the ground at the beginning of winter, and in spring make
a rapid growth from the materials laid up in the roots.
50.	Extent of the Root-System.—The total length of
the roots of ordinary plants is much greater than is usually
supposed. They are so closely packed in the earth that
only a few of the roots are seen at a time during the
process of transplanting, and when a plant is pulled or dug
up in the ordinary way a large part of the whole mass of
roots is broken off and left behind. A few plants have
been carefully studied to ascertain the total weight and
length of the roots. Those of winter wheat have been
found to extend to a depth of seven feet. By weighing
the whole root-system of a plant and then weighing a
known length of a root of average diameter, the total
length of the roots may be estimated. In this way the
roots of an oat plant have been calculated to measure
.about 154 feet; that is, all the roots, if cut off and strung
together end to end, would reach that distance.
51.	Absorption of Water by Roots. — Many experiments
on the cultivation of corn, wheat, oats, beans, peas, and
other familiar plants in water have proved that some plants,40
ESSENTIALS OF BOTANY
at any rate, can thrive very well on ordinary lake, river, or
well water, together with the food which they absorb from
the air (Chapter XIII). Just how much water some kinds
of plants give off (and therefore absorb) per day will be
discussed when the uses of the leaf are studied. For the
present it is sufficient to state that even an annual plant
during its lifetime absorbs through the roots very many
times its own weight of water. Grasses have been known
to take in their weight of water in every twenty-four hours
of warm, dry weather. This absorption takes place mainly
through the root-hairs, which the student has examined
as they occur in the seedling plant, and which are found
thickly clothing the younger and more rapidly'growing
parts of the roots of mature plants. Some idea of their
abundance may be gathered from the fact that on a rootlet
of corn grown in a damp atmosphere, and about Jy inch in
diameter, 480 root-hairs have been counted on each hun-
dredth of an inch in length. The walls of the root-hairs are
extremely thin, and they are free from any holes or pores
wffiich can be seen even by the highest power of the micro-
scope, yet the water of the soil penetrates very rapidly to
the interior of the rootdiairs. The soil-water brings with
it all the substances which it can dissolve from the earth
about the plant; and the closeness with which the root-
hairs cling to the particles of soil, as shown in Fig. 19,
must cause the water which is absorbed to contain more
foreign matter than underground water in general does,
particularly since the roots give off enough weak acid
from their surface to corrode the surface of stones which
they enfold or cover.
52. Movements of Young Roots. — The fact that roots
usually grow downward is so familiar that we do notROOTS
41
generally think of it as a thing that needs discussion or
explanation. Since they are pretty flexible, it may seem
as though young and slender roots merely hung down
by their own weight, like so many bits of wet cotton
twine. But a very little experimenting will answer the
question whether this is really the case. Making fine
equidistant cross-marks with ink along the upper and the
lower surface of a root that is about to bend downward at
the tip readily shows that those of the upper series soon
come to be farther apart, — in other words, that the root is
forced to bend downward by the more rapid growth of its
upper as compared with its under surface.
53.	Direction taken by Secondary Roots. — As the student
has already noticed in the seedlings which he has studied,
the branches of the primary root usually make a consider-
able angle with it. Often they run out for long distances
almost horizontally. This is especially common in the roots
of forest trees, above all in cone-bearing trees, such as pines
and hemlocks. This horizontal or nearly horizontal position
of large secondary roots is the most advantageous arrange-
ment to make them useful in staying or guying the stem
above to prevent it from being blown over by the wind.
54.	Fitness of the Root for its Position and Work. — The
distribution of material in the woody roots of trees and
shrubs and their behavior in the soil show many adapta-
tions to the conditions by which the roots are surrounded.
The growing tip of the root, as it pushes its way through
the soil, is exposed to bruises; but these are largely warded
off by the root-cap. The tip also shows a remarkable
sensitiveness to contact with hard objects, so that when
touched by one it swerves aside and thus finds its way
downward by the easiest path. Roots with an unequal42
ESSENTIALS OF BOTANY
water supply on either side grow toward the moister soil.
Roots are very tough, because they need to resist strong
pulls, but not as stiff as stems and branches of the same
size, because they do not need to withstand sidewise pres-
sure, acting from one side only. The corky layer which
covers the outsides of roots is remarkable for its power
of preventing evaporation. It must be of use in retaining
in the root the moisture which otherwise might be lost
on its way from the deeper rootlets (which are buried in
damp soil) through the upper portions of the root-system,
about which the soil is often very dry.
55.	Propagation by Means of Roots. — Some familiar
plants, such as rose bushes, are usually grown from roots
or root-cuttings.
Bury a sweet potato or a dahlia root in damp sand and watch
the development of sprouts from adventitious buds. One sweet
potato will produce several such crops of sprouts, and every sprout
may be made to grow into a new plant. It is in this way that the
crop is started wherever the sweet potato is grown for the market.
56.	Review Summary of Roots.
Kinds of roots as regards origin ....
Kinds as regards medium in which they grow
Structure of root of a tree.
Storage in roots................ .	.
Absorption of water by roots............
Movements of roots...................
/
l
I
materials.
location.
L uses,
r apparatus,
| amount,
nature,
causes,
uses.CHAPTER V
PLANT-CELLS; SOME FUNCTIONS OF CELLS IN THE ROOT
57. Structure of a Plant-Cell. — Plants are made up of
elementary organs called cells. These are small (usually
microscopic) objects of man}’ different shapes and subserve
various purposes in the life of the plant. The simplest
plants of all consist of but a single cell, which may have any
one of a great variety of shapes, but is often nearly spher-
ical. The higher plants, such as all the flowering plants,
consist of hundreds of thousands or millions of cells each,
and the total number hi a large tree is inconceivably great.
growing shoot of any of
the higher plants, when
much magnified, is seen
to consist of a cell-wall
(tt\ Fig. 20) filled with a
more or less liquid sub-
stance known as proto-
		
mSm		
c'y ‘ n w		r
Fig. 20. Two rapidly Growing Cells (both
pletsm. A large part of greatly magnified, J. twice as much as B).
the bulk of this proto- A is a very young cell in which the proto-
i_____________ ■	; p	plasm does not as vet show vacuoles. B
pliibHi consists oi ci . ,,	\	-i
±	is older, with several vacuoles; ?*, nucleus;
roundish object H, called nc, nucleolus; cy, protoplasm or cyto-
the nucleus, and inside plasm; r' vacu<,ks: w' ®sl!-wa11-
this is a more opaque body nc, called the nucleolus. As
the cell grows the protoplasm is soon found to separate
4344
ESSENTIALS OF BOTANY
into mucilaginous or jelly-like portions and watery enclosed
droplets known as vacuoles. The liquid which constitutes
the vacuoles is called cell-sap.
The cell-wall is made of a substance called cellulose,
which is familiar to every one in the form of cotton. A
bit of cotton wool is nearly, pure cellulose. Chemically it
is a very inactive substance, and its main use as a part of
the cell is to form a tough covering for it through which
liquids can readily soak in or out.
58. Characteristics of Living Protoplasm.1 — The proto-
plasm is the active part of every cell and all the work of
the plant is done by the cell protoplasm, generally in the
higher plants, by the cooperation of many thousands of
protoplasts (as the little protoplasmic units are called).
The remarkable powers which belong to living protoplasm
have been summed up as follows.
(1)	The power to take up new material into its own sub-
stance (selective absorption). This is not merely a process
of soaking up liquids, as a sponge absorbs water. The
protoplasmic lining of a root-hair, for example, selects
from the soil-water some substances and rejects others.
(2)	The ability to change certain substances into others
of different chemical composition (assimilation or metas-
tasis, Sect. 166). The way in which the stored plant-food
of seeds is changed into the materials of the young seed-
ling (Sects. 9, 10) is an example of assimilative action
exerted by special cells in and adjoining the embryo.
Many other instances occur.
(3)	The power to cast off waste or used-up material (excre-
tion). Getting rid of surplus water and of oxygen consti-
tutes a very large part of the excretory work of plants.
1 See Huxley’s Essays, Vol. I, essay on The Physical Basis of Life.PLANT-CELLS
45
(4)	The capacity for growth and. the production of off-
spring (reproduction). These are especially characteristic
of living protoplasm.
(5)	The possession of the power of originating move-
ments not wholly and directly caused by any external
impulse (automatic movements). Such, for instance, are
the lashing movements of the cilia of minute plants and
spores, Figs. 157, 169.
(6)	The power of shrinking or closing up (contractility).
(7)	Sensitiveness when-touched or otherwise disturbed.
This is shown by insect-catching leaves (Sect, 140), by the
leaves of sensitive plants, and parts of certain flowers.
The most remarkable and peculiar of the characteristics
of protoplasm as above given are due to its possessing irri-
tability. By this is meant the power to respond in some
definite way to any suitable stimulus or exciting cause,
acting from within or without the plant body. Some of
the principal stimuli are gravity, heat, light, chemical sub-
stances, and contact with solid objects.
59. Osmosis. — In order to understand the selective
absorption which constitutes a large part of the work of
the roots of plants it is necessary first to study osmosis.
This is the process by which two liquids separated by
membranes pass through the latter and mingle.
It is readily demonstrated by experiments with thin
animal or vegetable membranes.
EXPERIMENT X
Osmosis as shown in an Egg. — Cement to the smaller end of an egg
a bit of glass tubing about six inches long and about three-sixteenths
of an inch inside diameter. Sealing-wax or a mixture of equal parts
of beeswax and resin melted together will serve for a cement.46
ESSENTIALS OF BOTANY
Chip away part of the shell from the larger end of the egg, place
it in a wide-mouthed bottle or a small beaker full of water, as shown
in Fig. 21, then very cautiously pierce a hole through the upper end
of the eggshell by pushing a knitting-needle or
wire down through the glass tube.
Watch the apparatus for some hours and note
any change in the contents of the tube. Explain.
The rise of liquid in the tube is evidently due
to water making its way through the thin mem-
brane which lines the eggshell, although this mem-
brane contains no pores visible even under the
microscope.
Fio. 21. Egg on Beaker of Water,
to show Osmosis.
Fig. 22.
A, a very young root-hair; B, a
much older one (both greatly
magnified), e, cells of the epi-
dermis of the root; n, nucleus;
•s, watery cell-sap; p, thicker
protoplasm lining the cell-wall.
60. Osmosis in Root-Hairs. — The soil-water (practically
identical with ordinary spring or well water) is separated
from the more or less sugary or mucilaginous sap inside
of the root-hairs only by their delicate cell-walls linedFUNCTIONS OF ROOT
47
with a thin layer of protoplasm (Fig. 22). This soil-water
will pass rapidly into the plant, while very little of the
sap will come out. The selective action, which causes the
flow of liquid through the root-hairs to be almost wholly
inward, is due to the living layer of protoplasm, which
covers the inner surface of
the cell-wall of the root-hair.
When the student has learned
how active a substance proto-
plasm often shows itself to
be, he will not be astonished
to find it behaving almost as
though it were possessed of
intelligence and will. Trav-
eling by osmotic action from
cell to cell, a current of water
derived from the root-hairs is
forced up through the roots
and into the stem, just as
the contents of the egg was
forced up into the tube shown
in Fig. 21.
61. Sap-Pressure. — The
force with which the upward-
flowing current of water
presses may be estimated by
attaching a mercury gauge
to the root of a tree or the
stem of a small sapling. This is best done in early spring
after the thawing of the ground but before the leaves
have appeared. The experiment may also be performed
indoors upon almost any plant with a moderately firm
Fig. 23. Apparatus to measure
Sap-Pressure.
T, large tube fastened to the stump of
the dahlia stem by a rubber tube;
rr, rubber stoppers; t, bent tube
containing mercury; 11', upper and
lower level of mercury in T.48
ESSENTIALS OF BOTANY
stem through which the water from the soil rises freely.
A dahlia plant or a tomato plant answers well, though the
sap-pressure from one of these will not be nearly as great
as that from a larger shrub or a tree growing out of doors.
In Fig. 23 the apparatus is shown attached to the stem of
a dahlia. The difference of level of the mercury in the
bent tube serves to measure the sap-pressure. For every
foot of difference in level there must he a pressure of
nearly six pounds per square inch on the stump at the
base of the tube T.1
A black-birch root tested in this way at the end of
April has given a root-pressure of thirty-seven pounds to
the square inch. This would sustain a column of water
about eighty-six feet high.
1 See Appendix II.CHAPTER VI
STEMS
62.	What the Stem is—The work of taking in the raw
materials which the plant makes into its own food is done
mainly by the roots and the leaves. These raw materials
are taken from earth, from water, and from the air (see
Chapter XIII). The stem is that part or organ of the plant
which serves to bring roots and leaves into communica-
tion with each other. In most flowering plants the stem
also serves the important purpose of lifting the leaves
up into the sunlight where alone they can best do their
special work.
The student has already, in Chapter III, learned some-
thing of the development of the stem and the seedling;
he has now to study the external appearance and internal
structure of the mature stem. Much in regard to this
form and structure can conveniently be learned from the
examination of twigs and branches of our common forest
trees in their winter condition.
63.	The Horse-Chestnut Twig.1 — Procure a twig of horse-chestnut
eighteen inches or more in length. Make a careful sketch of it,
trying to bring out the following points.
(1) The general character of the bark.
1 Where tlic buckeye is more readily obtained it will do very well. Hickory
twigs answer the same purpose, and the latter is a more typical form, having
alternate buds. The magnolia or the tulip tree will do. The student should
(sooner or later) examine at least one opposite- and one alternate-leaved twig.
4950
ESSENTIALS OF BOTANY
(2)	The large horseshoe-shaped sears and the number and posi-
tion of the dots on these scars. Compare a sear with the base of a
leaf-stalk furnished by the teacher.
(3)	The ring of narrow scars around the stem in one or more
places,1 and the different appearance of the bark above and below
such a ring. Compare these scars with those left after removing the
scales of a terminal bud.
(4)	The buds at the upper margin of each leaf-scar and the
strong terminal bud at the end of the twig.
(5)	The flower-bud scar, a concave impression, to be found in the
angle produced by the forking of two twigs, which form, with the
branch from which they spring, a Yx-shaped figure.
(6)	(On a branch larger than the twig handed round for indi-
vidual study) the place of origin of the twigs on the branch. Make
a separate sketch of this.
The portion of stem which originally bore any pair of leaves is called
a node, and the portions of stem between nodes are called internodes.
Describe briefly in writing alongside the sketches any observed
facts which the drawings do not show.
If your twig was a crooked, rough-barked, and slow-growing one,
exchange it for a smooth, vigorous one, and note the differences.
Or if you sketched a quickly grown shoot, exchange for one of the
other kind.
Answer the following questions :
(a)	IIow many inches did your twig grow during the last summer ?
How many in the summer before V
How do you know ?
IIow many years old is the whole twig given you?
(b)	How were the leaves arranged on the twig ?
IIow many leaves were there?
Were they all of the same size ?
(c)	What has the mode of branching to do with the arrangement
of the leaves? with the flower-bud scars?
(d)	The dots on the leaf-scars mark the position of the bundles
of ducts and wood-cells which run from the wood of the branch
through the leaf-stalk up into the leaf.
1 A very vigorous shoot may not show any such ring.STEMS
51
64. Twig of Poplar. — Sketch a vigorous young twig of poplar (or
of hickory, magnolia, tulip tree) in its winter condition, noting par-
ticularly the respects in which it differs from the horse-chestnut.
Describe in writing any facts not shown in the sketch. Notice that
the buds are not opposite, nor is the next one above any given bud
found directly above it, but pai’t way round the stem from the
position of the first one. Ascertain, by studying several twigs and
counting around, which bud is above the first and how many turns
round the stern are made in passing from the first to the one directly
above it.
Observe with especial care the difference between the poplar and
the horse-chestnut in mode of branching, as shown in a large branch
provided for the study of this feature.
65.	Relation of Leaf Arrangement to Branching.1 — This
difference depends on the fact that the leaves of the horse-
chestnut were arranged in pairs on opposite sides of the
stem, while those of the poplar were not in pairs. Since
the buds are found at the upper edges of the leaf-scars, and
since most of the buds of the horse-chestnut and the poplar
are leaf-buds and destined to form branches, the mode of
branching and ultimately the form of the tree must depend
largely on the arrangement of leaves along the stem.
66.	Opposite Branching. — In trees, the leaves and buds
of which are opposite, the tendency will be to form twigs
in four rows about at right angles to each other along the
sides of the branch, as shown in Fig. 24.
This arrangement will not usually be perfectly carried
out, since some of the buds may never grow, or some may
1 The teacher in the Eastern and Middle States will do well to make con-
stant use, in the study of branches and buds, of Newell’s Outlines of Lessons
in Botany, Part I. The student can observe for himself, with a little guid-
ance from the teacher, most of the points which Miss Newell suggests. If the
supply of material is abundant, the twigs employed in the lessons above
described need not be used further, but if material is scanty, the study of buds
may at once be taken up. (See also Bailey’s Lessons with Plants, Part I.)52
ESSENTIALS OF BOTANY
grow much faster than others and so make the plan of
branching less evident than it would be if all grew alike.
67. Alternate Branching. — In
trees like the beech the twigs will
be found to be arranged in a more
or less regular spiral line about the
branch. This, which is known as
the alternate arrangement (Fig. 25),
is more commonly met with in trees
and shrubs than
the opposite ar-
rangement. It
admits of many
varieties, since
the spiral may
wind more or
less rapidly
round the stem.
Fig. 24. Opposite Branch- Jn	apple,
ing in a very Young Sap-	,
ling of Ash.	Pear’ cherry,
poplar, oak, and
walnut, one passes over five spaces before
coming to a leaf which is over the first,
and in doing this it is necessary to make
two complete turns round the stem.
68. Growth of the Terminal Bud. — In
some trees the terminal bud from the
very outset keeps the leading place, and Fig. go. Alternate
the result of this mode of growth is to Branching in a very
produce a slender, upright tree, with an
excurrent trunk like that of Fig. 232. In such trees as the
apple and many oaks the terminal bud has no preeminenceSTEMS
53
over others, and the form of the tree is round-topped and
spreading, deliquescent like that in Fig. 235.
Most of the larger forest trees are intermediate between
these extremes.
Branches get their characteristics to a considerable
degree from the relative importance of their terminal
buds. If these are mainly flower-buds, as is the case in
the horse-chestnut, the tree is characterized by frequent
forking, and has no long horizontal branches.
If the terminal bud keeps the lead of the lateral ones,
but the latter are numerous and most of them grow into
slender twigs, the delicate spray of the elm and many
birches is produced (Fig. 26).
The general effect of the branching depends much upon
the angle which each branch or twig forms with that one
from which it springs. The angle may be quite acute,
as in the birch, or more nearly a right angle, as in the
ash (Fig. 24).
It is these differences that help to give to leafless woods
in winter their unending variety and beauty.54
ESSENTIALS OF BOTANY
69.	Indefinite Annual Growth. — In most of the forest
trees, and in the larger shrubs, the wood of the branches
is matured and fully developed during the summer, and
protected buds are formed on the twigs to their very tips.
In other shrubs — for example, in the sumac, the rasp-
berry, and blackberry — the shoots continue to grow until
their soft and partly matured tips are killed by the frost.
Such a mode of growth is called indefinite annual growth, to
distinguish it from the definite annual growth of most trees.
70.	Trees, Shrubs, and Herbs. — Plants of the largest
size, with a main trunk of a woody structure, are called
trees. Shrubs differ from trees in their smaller size, and
generally in their more forking and divided stem. The
witch-hazel, the dogwoods, and the alders, for instance,
are most of them classed as shrubs for this reason, though
in height some of them equal the smaller trees. Some of
the smallest shrubby plants, like the blueberry, the win-
tergreen, and the trailing arbutus, are only a few inches
in height, but are ranked as shrubs because their woody
stems do not die quite to the ground in winter.
Herbs are plants whose stems above ground die every
winter.
71.	Annual, Biennial, and Perennial Plants.—Annual
plants are those which live but one year, biennials those
which live nearly or quite two years.
Some annual plants may be made to live over winter,
flowering in their second summer. This is true of winter
wheat and rye among cultivated plants.
Perennial plants live for a series of years. Many kinds
of trees last for centuries. The Californian giant red-
woods, or Sequoias, which reach a height of over 300 feet
under favorable circumstances, live nearly 2000 years ; andSTEMS
55
some very large cypress trees found in Mexico were thought
by Professor Asa Gray to be from 4000 to 5000 years old.
72. “ Stemless Plants.”—The so-called stemless plants,
like the dandelion (Fig. 27) and some violets, are not really
stemless at all, but send out their leaves and flowers from
a very short stem
which hardly rises
above the surface of
the ground.
Now, as will be
shown later (Chap-
ter XXI), plants live
subject to a very
fierce competition
among themselves
and exposed to
almost constant at-
tacks from animals.
Any plant which
can grow in safety
under the very feet
of grazing animals
will be especially
likely to make its
way in the world, since there are many places where it can
flourish while ordinary plants would be destroyed. The
bitter, stemless dandelion, which is almost uneatable for most
animals, unless cooked, which lies too near the earth to be
fed upon by grazing animals, and which bears being trodden
on with impunity, is a type of a large class of hardy weeds.
. And while plants with long stems find it to their
account to reach up as far as possible into the sunlight,
Fig. 27. The Dandelion ; a so-Galled
Stemless Plant.56
ESSENTIALS OF BOTANY
the cinquefoil, the white clover, the dandelion, the spurges,
the knot-grass, and hundreds of other kinds of plants have
found safety in hugging the ground.
73. Climbing and Twining Stems.1 — Since it is essential
to the health and rapid growth of most plants that they
should have free access to the sun and air, it is not strange
that many should resort to special
devices for lifting themselves
above their neighbors. In trop-
ical forests, where the darkness of
the shade anywhere beneath the
tree-tops is so great that few
^	flowering plants can thrive in
§f	it, the climbing plants, or lianas,
often run like great cables for
hundreds of feet before they can
emerge into the sunshine above,
and share the light with the trees
which support them. In temper-
ate climates no such remarkable
climbers are found, but many
plants raise themselves for con-
siderable distances. The princi-
pal means to which they resort
for this purpose are:
(1)	Producing roots at many points along the stem above
ground and climbing on suitable objects by means of these,
as in the English ivy (Fig. 13).
(2)	Laying hold of objects by means of tendrils or tunn-
ing branches or leaf-stalks (Figs. 28, 29).
(3)	Twining about any slender upright support (Fig. 30).
1 See Kernel- and Oliver’s Natural History of Plants, Vol. X, p. 669.
Fig. 28. Coiling of a Tendril
of Bryony.■ STEMS
57
Fig. 29. Coiling of
Petiole of Dwarf
Tropaeolum.
74.	Tendril-Climbers. —The plants which climb by means
of tendrils are very interesting subjects for study, but they
cannot usually be managed very well in the schoolroom.
Continued observation soon shows that the tips
j of tendrils sweep slowly about in the air until
they come in contact with
some object about which
they can coil themselves.
After the tendril has taken
a few turns about its sup-
port, the free part of the
tendril coils into a spiral
and thus
draws the
whole stem
toward the point of attachment, as shown
in Fig. 28. Some tendrils are leaves or
stipules, others are modified stems.
75.	Twiners.1 — Only a few of the
upper internodes of the stem of a twi-
ner are concerned in producing
the movements of the tip of the
stem. This is kept revolving in
an elliptical or circular path un-
til it encounters some roughish
and not too stout object about
which it then proceeds to coil
itself. The direction of the coil-
ing varies in different kinds of
climbers, some following the course shown in the figure
Fig. 30. Twining Stem
of Hop.
1 See article on Climbing Plants, by Dr. W. J. Beal, in the American Nat-
uralist, Vol. IV, pp. 405-415.58
ESSENTIALS OF- BOTANY
of the hop (Fig. 30); others,
as the morning-glory, tak-
ing the opposite course.1
76. Underground Stems.
— Stems which lie mainly
or wholly underground are
of frequent occurrence and
of many kinds.
In the simplest form of
rootstock (Fig. 31), such as
is found in some mints and
in many grasses and sedges,
the real nature of the creep-
ing underground stem is
Fig. 31.
shown by the presence
upon its surface of many
scales, which are reduced
leaves. Rootstocks of this
sort often extend horizon-
tally for long distances in
the case of grasses like the
sea rye grass, which roots
itself firmly and thrives in
shifting sand-dunes. In
the stouter rootstocks, like
that of
the iris
(Fig. 32)
Rootstock of Cotton-Grass (Eriophorum).	and tile
1 See Strasburger, Noll, Schenk, and Kars ten’s Text-Book, pp. 257-260;
also Vines, Students' Text-Book of Botany, London and New York, 1894,
pp. 759, 760.STEMS
59
Caladium, this stem-like character is less evident. The
potato is an excellent example of the short and much-
thickened underground stem known as a tuber.
It may be seen from Fig. 38 that the potatoes are none
of them borne on true roots,
but only on subterranean
branches, which are stouter
and more cylindrical than
most of the roots. The
“ eyes ” which they bear are
rudimentary leaves and
buds.
Bulbs, whether coated like
those of the onion or the
hyacinth (Fig. 34), or scaly
like those of the lily, are
merely very short and stout
underground stems, covered
with closely crowded scales
or layers which represent
leaves or the bases of leaves
(Fig. 35).
The variously modified
forms of underground stems
just discussed illustrate in a
marked way the storage of
nourishment during the
winter (or the rainless sea-
son, as the case may be) to secure rapid growth during
the active season. It is interesting to notice that nearly
all of the early flowering herbs in temperate climates, like
the crocus, the snowdrop, the spring-beauty, the tulip, and
Fiu. 32. Roots, Rootstocks,
and Leaves of Iris.6(0
ESSENTIALS OF BOTANY
The dark tuber in the middle is the one from which the plant has grown.
Fig. 34. Bulb of Hyacinth.
Exterior view and split lengthwise.STEMS
61
the skunk-cabbage, owe their early-blooming habit to richly
stored underground stems of some kind, or to thick,
fleshy roots.
77.	Condensed Stems. — The plants of desert regions
require, above all, protection from the extreme dryness of
the surrounding air, and, usually, from the excessive heat
of the sun. Accordingly many desert
plants are found quite destitute of
ordinary foliage, exposing to the air
only a small surface. In the melon-
cactuses (Fig. 81) the stem appears
reduced to the shape in which the
least possible surface is presented by
a plant of given bulk, — that is, in a
globular form. Other cactuses are
more or less cylindrical or prismatic,
while still others consist of flattened
joints; but all agree in offering much
less area to the sun and air than is
exposed by an ordinary leafy plant.
78.	Leaf-like Stems— The flattened
stems of some kinds of cactus (espe-
cially the common, showy Phyllocactus)
are sufficiently like fleshy leaves, with
their dark green color and imitation
of a midrib, to pass for leaves. There
are, however, a good many cases in
which the stem takes on a more strikingly leaf-like form.
The common asparagus sends up in spring shoots that bear
large scales which are really reduced leaves. Later in the
season, what seem like thread-like leaves cover the much-
branched mature plant, but these green threads are actually
sea
Fig. 35. Longitudinal
Section of an Onion
Leaf.
sea, thickened base of
leaf, forming a bulb-
scale ; s, thin sheath
of leaf; bl, blade of
leaf; int, hollow in-
terior of blade.62
ESSENTIALS OF BOTANY
minute branches, which perform the work of leaves (Fig. 36).
The familiar greenhouse climber, wrongly known as srnilax
(properly called Myrsiphyllum), bears a profusion of what
appear to be delicate green leaves (Fig. 37). Close study,
however, shows that these are really short, flattened
branches, and that each little branch springs from the
Fig. 36. A Spray of a Common Asparagus (not the edible species).
axil of a true leaf, l, in the form of a minute scale. Some-
times a flower and a leaf-like branch spring from the axil
of the same scale.
Branches which, like those of Myrsiphyllum, so closely
resemble leaves as to be almost indistinguishable from
them are called cladophylls.
79. Modifiability of the Stem. — The stem may, as in the
tallest trees in the great lianas of South American forests
or the rattan of Indian jungles, reach a length of many
hundred feet. On the other hand, in such “ stemless ”STEMS
63
plants as the primrose and the dandelion, the stem may
be reduced to a fraction of an inch in length. It may
take on apparently root-like forms, as in many grasses and
sedges, or become thickened by underground deposits of
starch and other plant-food, as in the iris, the potato, and
Pig. 37. Stem of “Smilax” (Myrsiphyllum).
I, seale-like leaves; cl, cladophyll, or leaf-like branch, growing in the axil
of the leaf; ped, flower-stalk, growing in the axil of a leaf.
the crocus. Condensed forms of stem may exist above
ground, or, on the other hand, branches may be flat and
thin enough to imitate leaves closely. In short, the stem
manifests great readiness in adapting itself to the most
varied conditions of existence.64
ESSENTIALS OF BOTANY
80. Review Summary of Stems.1
Kinds of branching due to leaf arrangement .	.	.	.
Kinds of tree-trunk due to greater or less predominance
of terminal bud...................................
Classes of plants based on amount of woody stem
Classes of plants based on duration of life.......
Various modes of climbing.........................
Kinds of underground stem ........................
n
{2
ri
1
Condensed stems above ground
Leaf-like stems
1 Where it is possible to do so, make sketches; where this is not possible,
give examples of plants to illustrate the various kinds or classes of plants in
the summary.CHAPTER YII
STRUCTURE OF THE STEM
STEM OF MONOCOTYLEDONOUS PLANTS
81. Gross Structure. — Refer back to the sketches of the corn-
seedling to recall something of the early history of the corn-stem.
Study the external appearance of a piece of corn-stem or bamboo
two feet or more in length.
Note the character of the outer
surface. Sketch the whole piece
and label the enlarged nodes
and the nearly cylindrical inter-
nodes. Cut across a corn-stem
and examine the cut surface
with the magnifying glass.
Make some sections as thin as
they can be cut and examine
with the magnifying glass
(holding them up to the light)
or with a dissecting microscope.
Note the firm rind composed of
the epidermis and underlying
tissue, the large mass of pith j-IG gg Diagrammatic Cross-Section
composing the main bulk of	0f stem of Indian Com.
the stem, and the many little ^ fibro_vascular Wles; gc, pithy
harder and more opaque spots,	material between bundles,
which are the cut-off ends of
the woody threads known as Jibro-vascular bundles (Fig. 38, cr).
Split a portion of the stem lengthwise into thin translucent slices
and notice whether the bundles seem to run straight up and down
6566
ESSENTIALS OF BOTANY
its length; sketch the entire section x 2. Every fibro-vascular bundle
of the stem passes outward through some node in order to connect
with some fibro-vascular bundle of a leaf. This fact being known
to the student would lead him to expect to find the bundles bending
out of a vertical position more at the nodes than elsewhere. Can
this be seen in the stem examined?
Observe the enlargement and thickening at the nodes, and split
one of these lengthwise to show the tissue within it.
Compare with the corn-stem a piece of palmetto and a piece of
cat-brier (Smilax rotundifolia, S. liispida, etc.), and notice the simi-
larity of structure, except for the fact that the tissue in the palmetto
and the cat-brier, which answ'ers to the pith of the corn-stem, is much
darker colored and harder than corn-stem pith. Compare also a
piece of rattan and of bamboo.
82.	Minute Structure. — Cut a thin cross-section of the corn-stem,
examine with a low porver of the microscope, and note :
(a)	The rind (not true bark), composed largely of hard, thick-
walled dead cells known as sclerenchyma fibers.
(b)	The fibro-vascular bundles. Where are they most abundant?
least abundant ?
(c)	The pith, occupying the intervals between the fibro-vascular
bundles.
Study the bundles in various portions of the section and notice
particularly whether some are more porous than others. Explain.
Sketch some of the outer and some of the inner ones.
A more complicated kind of monocotyledonous stem-structure
can be studied to advantage in the surgeons’ splints cut from yucca-
stems and sold by dealers in surgical supplies.
83.	Mechanical Function of the Manner of Distribution of
Material in Monocotyledonous Stems____________The well-known
strength and lightness of the straw of our smaller grains
and of rods of cane or bamboo are due to their form. It
can readily be shown by experiment that an iron or
steel tube of moderate thickness, like a piece of gas-pipe
or of bicycle-tubing, is much stiller than a solid rod ofPhotograph furnished by the United Fruit Co.
Plate II. Cocoa Palms.STRUCTURE OF THE STEM
67
the same weight per foot. The oat straw, the stems of
bulrushes, the cane (of our southern canebrakes), and the
bamboo are hollow cylinders; the cornstalk is a solid
cylinder, but filled with a very light pith. The flinty
outer layer of the stalk, together with the closely packed
sclerenchyma fibers of the outer rind and the frequent
fibro-vascular bundles just within this, are arranged in the
best way to secure stiffness. In a general way, then, we
may say that the pith, the bundles, and the sclerenchyma-
tous rind are what they are and where they are to serve
important mechanical purposes. But they have other uses
fully as important.
84. Growth of Monocotyledonous Stems in Thickness. —
In most woody monocotyledonous stems, for a reason
which will be explained later in this chapter, the increase
in thickness is strictly limited. Such stems, therefore, as
in many palms and in rattans, are less conical and more
cylindrical than the trunks of ordinary trees and are also
more slender in proportion to their height (Plate II).
STEM OF DICOTYLEDONOUS PLANTS
85. Gross Structure of an Annual Dicotyledonous Stem. — Study
the external appearance of a piece of sunflower-stem several inches
long. If it shows distinct nodes, sketch it. Examine the cross-
section and sketch it as seen with the magnifying glass or the dissect-
ing microscope. After your sketch is finished, compare it with Fig. 39,
which probably shows more details than your drawing, and label
the parts shown as they are labeled in that figure. Split a short
piece of the stem lengthwise through the center and study the split
surface with the magnifying glass. Take a sharp knife or a scalpel
and carefully slice and then scrape away the bark until you come to
the outer surface of a bundle.68
ESSENTIALS OF BOTANY
Examine a vegetable sponge (Luffa), sold by druggists, and notice
that it is simply a network of iibro-vascular bundles. It is the skele-
ton of a tropical seed-vessel or fruit, very much like that of the wild
cucumber common in the Central States, but a great deal larger.
The different layers of the bark cannot all be 'well recognized in
the examination of a single kind of stem. Examine (a) the cork
Fig. 39. Diagrammatic Cross-Section of an Annual Dicotyledonous
Stem. (Somewhat magnified.)
p, pith; fv, woody or fibro-vascular bundles; e, epidermis; b, bundles of
hard bast fibers of the bark.
Fig. 40. Diagrammatic Cross-Section of One-Year-Old Aristolochia
Stem. (Considerably magnified.)
c, region of epidermis; b, hard bast; o, outer or bark part of a bundle
(the cellular portion under the letter); w, inner or woody part of
bundle; c, cambium layer; p, region of pith ; in, a medullary ray.
The space between the hard bast and the bundles is occupied by thin-
walled, somewhat cubical cells of the bark.STRUCTURE OF THE STEM
69
■which constitutes the outer layers of the hark of cherry or birch
branches two or more years old. Sketch the roundish or oval
spongy lenticels on the outer surface of the bark. How far in do they
extend ? Examine (b) the green layer of bark as shown in twigs or
o
P
Fig. 41. One Bundle from the Preceding Figure, (x 100.)
w, wood-cells; d, ducts. The other letters are as in Fig. 40. Many
sieve-cells occur in the region just outside of the cambium of
the bundle.
branches of Forsythia, cherry, alder, box-elder, wahoo, or willow.
Examine (c) the white, fibrous inner layer, known as hard bast, of
the bark of elm, leatherwood, pawpaw, or basswood.
86. Minute Structure of the Dicotyledonous Stem.—Study, first
with a low and then with a medium power of the compound micro-
scope, thin cross-sections of clematis-stem cut just before the end of70
ESSENTIALS OF BOTANY
the first season’s growth.1 Sketch the whole section without much
detail, and then make a detailed drawing of a sector running from
center to circumference and just wide enough to include one of the
large bundles. Label these drawings in general like Figs. 40, 41.
Note : (a) The general outline of the section.
(b)	The number and arrangement of the bundles. (How
many kinds of bundles are there?)
(c)	The comparative areas occupied by the woody part of the
bundle and by the part which belongs to the bark.
(d)	The way in w'hich the pith and the outer bark are con-
nected (and the bundles separated) by the medullary rays.
Fig. 42. Stem of Box-Elder One Year Old. (Much magnified.)
A, lengthwise (radial) section; B, cross-section, e, epidermis; ck, oork;
6, hard bast; s, sieve-cells; c, cambium; w, wood-cells; m, medullary
rays; d, ducts; p, pith.
Examine a longitudinal section of the same kind of stem to find
out more accurately of what kinds of cells the pith, the bundles, and
the outer bark are built. Which portion has cells that are nearly
equal in shape, as seen in both sections?
1 Clematis virginiana is simpler in structures than some of the other woody
species. Aristoloclua sections will do very wellSTRUCTURE OF THE STEM
71
87. The Early History of the Stem. — In the earliest
stages of the growth of the stem it consists entirely of
thin-walled and rapidly dividing cells. Soon, however,
the various kinds of tissue which
are found in the full-grown stem
begin to appear.
In Fig. 43 the process is shown
as it occurs in the castor bean.
At to, in Z?, is the central column
of pith surrounded by eight fibro-
vascular bundles, fv, each of
which contains a number of ducts
arranged in a pretty regular man-
ner and surrounded by the fore-
runners of the true wood-cells.
In C the section shows a con-
siderable advance in growth: the
fibro-vascular bundles are larger
and are now connected by a rap-
idly growing layer of tissue, cl.
As growth continues this layer
becomes the cambium layer, com-
posed of thin-walled and rapidly
dividing cells, as shown in Fig. 45.
88. Secondary Growth. — From
the inside of the cambium layer
the wood-cells and ducts of the
mature stem are produced, while
Fig. 43. Transverse Section
through the Hypocotyl of
the Castor-Oil Plant at Vari-
ous Stages. (Considerably
magnified.)
A, after the root has just ap-
peared outside the testa of
the seed ; B, after the caulicle
is nearly an inch long; C, at
the end of germination; r,
cortex (undeveloped bark);
m, pith; st, medullary rays;
fv, fibro-vascular bundles;
cb, layer of tissue which is to
develop into cambium.
from its outer circumference the new layers of the bark
proceed. From this mode of increase the stems of dicoty-
ledonous plants are called exogenous, that is, outside-
growing. The presence of the cambium layer on the72
ESSENTIALS OF BOTANY
outside of the wood in early spring is a fact well known
to the schoolboy who pounds the cylinder cut from an
alder, willow, or hickory branch until the bark will slip
off and so' enable him to make a whistle. The sweet
taste of this pulpy layer, as found in the white pine, the
slippery elm, and
the basswood, is a
familiar evidence of
the nourishment
which the cambium
layer contains.
With the increase
of the fibro-vascular
bundles of the wood
the space between
them, which ap-
pears relatively
large in Fig. 40, be-
comes less and less,
and the pith, which
at first extended
freely out toward
the circumference
of the stem, becomes
compressed into
thin plates so as to
form medullary rays.
These are, as already stated, of use in storing the food
which the plant in cold and temperate climates lays up
in the summer and fall for use in the following spring,
and in the very young stem they serve as an important
channel for the transference of fluids across the stem from
Fig. 44. Diagram to illustrate Secondary
Growth in a Dicotyledonous Stem.
R, the first-formed bark; p, mass of sieve-cells;
ifp, mass of sieve-cells between the original
wedges of wood; fc, cambium of wedges of
wood; ic, cambium between wedges; b, groups
of bast-cells; fh, wood of the original wedges;
ifh, wood formed between wedges; x, earliest
wood formed; M, pith.STRUCTURE OF THE STEM
73
bark to pith, or in. the reverse direction. On account,
perhaps, of their importance to the plants, the cells of
the medullary rays are among the longest lived of all
vegetable cells, retaining their vitality in the beech tree
sometimes, it is said, for more than a hundred years.
After the inter-
spaces between the
first fibro - vascular
bundles have be-
come filled up with
wood, the subse-
quent growth must
take place in the
manner shown in
Fig. 44. The cam-
bium of the original
wedges of wood,/c,
and the cambium, ic,
formed between
these wedges, con-
tinues to grow from
its inner and from
its outer surface,
and thus causes a
permanent increase
in the diameter of
the stem and a thickening of the bark, which, however,
usually soon begins to peel off from the outside and thus
soon attains a pretty constant thickness.
89. The Dicotyledonous Stem, thickened by Secondary Growth. —
Cut off, as smoothly as possible, a small branch of hickory and one
of white oak above and below each of the rings of scars already
Fig. 40. Cross-Section of a Three-Year-Old
Linden Twig. (Much magnified.)
E, epidermis and corky layer of the bark; B,
bast; C, cambium layer; if, annual rings
of wood.74
ESSENTIALS OF BOTANY
mentioned (Sect. 63), and count the rings of wood above and below
each ring of scars.
How do the numbers correspond? What does this indicate?
Count the rings of wood on the cutoff ends of large billets of
some of the following woods : locust, chestnut, sycamore, oak, hickory.
Do the successive rings of the same tree agree in thickness?
Why? or why not?
Does the thickness of the rings appear uniform all the way round
the stick of wood? If not, the reason in the case of an upright
stem (trunk) is perhaps that there was a greater spread of leaves on
the side where the rings are thickest or because there was unequal
pressure caused by bending before the wind.
Do the rings of any one kind of tree agree in thickness with those
of all the other kinds? What does this show?
In all the woods examined look for:
(a) Contrasts in color between the heartwood and the sapwood.1
(5) The narrow lines running, in vei-y young stems, pretty straight
from pith to bark, in older wood extending only a little of the way
from center to bark, the medullary rays shown in Fig. 42.2
(e) The wedge-shaped masses of wood between these.
(d) The pores which are so grouped as to mark the divisions
between successive rings. These pores indicate the cross-sections of
vessels or ducts. Note the distribution of the vessels in the rings to
which they belong; compare this with Fig. 45 and decide at what
season of the year the largest ducts are mainly produced. Make a
careful drawing of the end-section of one billet of wood, natural
size.
Cut off a grapevine several years old and notice the great size of
the vessels. Examine the smoothly planed surface of a billet of red
oak that has been split through the middle of the tree, and note the
large shining plates formed by the medullary rays.
Look at another stick that has been planed away from the out-
side until a good-sized flat surface is shown, and see how the medul-
lary rays are here represented only by their edges.
1	This is admirably shown in red cedar, black walnut, barberry, black
locust, and osage orange.
2	These and many oilier important things are admirably shown in the thin
wood-sections furnished for $5 per set of 2t by R. B. Hough, Lowville, N.Y.STRUCTURE OF THE STEM
75
90. Grafting. — When the cambium layer of any vigor-
ously growing stem is brought in contact with this layer
in another stem of the same kind or
a closely similar kind of plant, the two
may grow together to form a single
stem or branch. This process is called
grafting, and is much resorted to in
order to secure apples, pears, etc.,
of any desired kind (Fig. 46). A
twig known as the scion from a tree
of the chosen variety is grafted on to
any kind of tree of the same species
known as the stock, and the result-
ing stems will bear the wished-for
kind of fruit. Often one species is
grafted on another, as the pear on the
quince or the apple. Rarely trees dif-
fering as much as the chestnut and the
oak may be grafted together. Some-
times grafting comes about naturally
by the branches of a tree chafing
against one another until the bark
is worn away and the cambium layer
of each is in contact with that of the
other, or two separate trees may be joined by natural
grafting.
Fig. 46. Grafting.
At tbe left scion and stock
are shown ready to be
united; at the right they
are joined and ready to
cover with grafting wax.CHAPTER VIII
LIVING PARTS OF THE STEM; WORK OF THE STEM
91. Active Portions of the Stems of Trees and Shrubs. —
In annual plants generally and in the very young shoots
of shrubs and trees there are stomata or breathing pores
which occur abundantly in the epidermis, serving for the
admission of air and the escape of moisture, while the
green layer of the bark answers the same purpose that is
served by the green pulp of the leaf (Chapter xili).
For years, too, the spongy lenticels, which succeed the
stomata and occur scattered over the external surface of
the bark of trees and shrubs, serve to admit air to the
interior of the stem. The lenticels at first appear as
roundish spots of very small size, but as the twig or shoot
on which they occur increases in diameter the lenticel
becomes spread out at right angles to the length of the
stem, so that it sometimes becomes a longer transverse slit
or scar on the bark, as in the cherry and the birch. But
in the trunk of a large tree no part of the bark except the
inner layer is alive. The older portions of the bark, such
as the highly developed cork of the cork-oak, from which
the ordinary stoppers for bottles are made, sometimes cling
for years after they are dead and useless except as a pro-
tection for the parts beneath against mechanical injuries
or against cold. But in many cases, as in the shell-bark
hickory and the grapevine, the old bark soon falls off in
7fiLIVING PARTS OF THE STEM
77
strips. The cambium layer is very much alive, and so
is the young outer portion of the wood. Testing this
sapwood, particularly in winter, when it serves for food
storage, shows that it is rich in starch and proteids.
The heartwood of a full-grown tree is hardly living
unless the cells of the medullary rays retain their vitality;
and so wood of this kind is useful to the tree mainly by
giving stiffness to the trunk and larger branches, thus
preventing them from being easily broken by storms.
It is, therefore, possible for a tree to flourish, sometimes
for centuries, after the heartwood has much of it rotted
away and left the interior of the trunk hollow. This is
well shown in the trunk of many old elms, sycamores, and
other trees. In the Sequoias, or big trees of California,
there are sometimes cavities large enough to allow a two-
horse covered wagon to drive inside; and the “ chestnut
of a hundred horses ” on Mt. Etna gets its name from the
fact that the interior cavity would easily hold that number
of horsemen. In this case, however, there is some doubt
whether the whole was originally a single trunk.
92. Uses of the Components of the Stem. — There is a
marked division of labor among the various groups of cells
that make up the stem of ordinary dicotyledons, partic-
ularly in the stems of trees, and it will be best to explain
the uses of the kinds of cells as found in trees rather than
in herbaceous plants. A few of the ascertained uses of
the various tissues are these:
The pith forms a large portion of the bulk of very
young shoots, since it is a part of the tissue of compara-
tively simple structure amid which the fibro-vascular bun-
dles arise. In mature stems it becomes unimportant, though
it often long continues to act as a storehouse of food.78
ESSENTIALS OF BOTANY
The medullary rays in the jmung shoot serve as a chan-
nel for the transference of water and plant-food in a liquid
form across the stem, and they often contain much stored
food.
The vessels carry water upward and (sometimes) air
downward through the stem.
The wood-cells of the heartwood are useful only to give
stiffness to the stem. Those of the sapwood, in addition
to this work, have to carry most of the water from the
roots to the leaves and other distant portions of the plant.
The cambium layer is the region in which the annual
growth of the tree takes place.
The most important portion of the inner bark is that
which consists of sieve-tubes, for in these digested and
elaborated plant-food is carried from the leaves toward
the roots.
The green layer of the bark in young shoots does much
toward collecting nutrient substances, or raw materials,
and preparing the food of the plant from air and water,
but this work may be best explained in connection with
the study of the leaf (Chapter XIII).
93. Movement of Water in the Stem. — The student has
already learned that large quantities of water are taken
up by the roots of plants.
Having become somewhat acquainted with the structure
of the stem, he is now in a position to investigate the
question as to how the various fluids, commonly known as
sap, travel about in it.1 It is important to notice that sap
is by no means the same substance everywhere and at all
times. As it first makes its way by osmotic action inward
1 See the paper on The So-called Sap of Trees and its Movements, by
Professor Charles R. Barnes, Science, Yol. XXI, p. 535.WORK OF THE STEM
79
through the root-hairs of the growing plant it differs but
little from ordinary spring water or well water. The
liquid which flows from the cut stem of a “ bleeding ”
grapevine, which has been pruned just before the buds
have begun to burst in the spring, is mainly water with
dissolved organic acids, proteids, and sugar. The sap which
is obtained from maple trees in late winter or early spring,
and is boiled down for syrup or sugar, is still richer in
nutritious material than the water of the grapevine, while
the elaborated sap which is sent so abundantly into the
ear of corn at its period of filling out, or into the grow-
ing pods of beans and peas, or into the rapidly forming
acorn or the chestnut, contains great stores of food suited
to sustain plant or animal life.
EXPERIMENT XI
Rise of Water in Stems. — Cut some short branches from an apple
tree or a cherry tree and stand the lower end of each in red ink;
try the same experiment with twigs of oak, ash, or other porous
wood, and after some hours 1 examine with a magnifying glass and
with the microscope, using the 2-inch objective, successive cross-
sections of one or more twigs of each kind. Note exactly the por-
tions through which the ink has traveled. Pull off the leaves from
one of the stems after standing in the eosin solution, and notice
the spots on the leaf-scar through which the eosin has traveled.
These spots show the positions of the leaf-traces, or fibro-vascular
bundles, connecting the stem and the leaf. Repeat with several
potatoes cut crosswise through the middle. Try also some mono-
cotyledonous stems, such as those of the lily or asparagus. For the
sake of comparison between roots and stems, treat any convenient
root, such as a parsnip, in the same way.
1 If the twigs are leafy and the room is warm, only from 5 to 30 minutes
may be necessary.80
ESSENTIALS OF BOTANY
Examine longitudinal sections of some of the. twigs, the potatoes,
and the roots. In drawing conclusions about the channels through
which the ink has risen (those through which the newly absorbed
soil-water most readily travels), bear in mind the fact that a slow
soakage of the red ink will take place in all directions, and there-
fore pay attention only to the strongly colored spots or lines.
What conclusions can be drawn from this experiment as to the
course followed by the sap V
From the familiar facts that ordinary forest trees appar-
ently flourish as well after the almost complete decay and
removal of their heartwood, and that many kinds will live
and grow for a considerable time after a ring of bark
extending all round the trunk has been removed, it may
readily be inferred that the crude sap in trees must rise
through some portion of the newer layers of the wood.
A tree girdled by the removal of a ring of sapwood
promptly dies.
94. Downward Movement of Liquids. — Most dicotyle-
donous stems, when stripped of a ring of bark and then
stood in water, as shown in Fig. 47, and covered with a
bell-jar, develop roots only at or near the upper edge of
the stripped portion,1 and this would seem to prove that
such stems send their building material — the elaborated
sap — largely at any rate down through the bark. Its
course is undoubtedly for the most part through the sieve-
cells (Fig. 42), which are admirably adapted to convey
liquids. In addition to these general upward and down-
ward movements of sap there must be local transfers
laterally through the stem, and these are at times of much
importance to the plant.
1 This may he made the subject of a protracted class-room experiment.
Strong shoots of willow should be used for the purpose.WORK OF THE STEM
81
Since the liquid building material travels straight down
the stem, that side of the stem on which the manufacture of
such material is going on most rapidly should grow fastest.
95. Causes of Movements of Water in the Stem. — Some
of the phenomena of osmosis were explained in Sect. 60,
and the work of the root-hairs was
described as due to osmotic action.
Root-pressure (Sect. 61), being
apparently able to sustain a col-
umn of water only eighty or
ninety feet high at the most, and
usually less than half this amount,
would be quite insufficient to raise
the sap to the tops of the tallest
trees; some other force or forces
must step in to carry it the rest
of the way. What these other
forces are is still a matter of dis-
cussion among botanists.
The slower inward and down- Fig. 47. A Cutting girdled
ward movement of the sap may	and sending down Roots
be explained as due to osmosis.	from the Upper EdSe of
„	.	.	,	.	the Girdled Ring.
f1 or instance, in the case of grow-
ing wood-cells, sugary sap descending from the leaves
into the stem gives up part of its sugar to form the
cellulose of which the wood-cells are being made.
This loss of sugar would leave the sap rather more
watery than usual, and osmosis would carry it from the
growing wood to the leaves, while at the same time a slow
transfer of the dissolved sugar will be set up from leaves
to wood. The water will be thrown off in the form of
vapor as fast as it reaches the leaves, so that they will not82
ESSENTIALS OF BOTANY
become distended, while the sugar will be changed into
cellulose and built into new wood-cells as fast as it reaches
the region where such cells are being formed.
Plants in general1 readily change starch to sugar, and
sugar to starch. When they are depositing starch in any
part of the root or stem for future use, the withdrawal of
sugar from those portions of the sap which contain it most
abundantly gives rise to a slow movement of dissolved
particles of sugar in the direction of the region where
starch is being laid up.
96.	Storage of Food in the Stem. — The reason why the
plant may profit by laying up a food supply somewhere
inside its tissues has already been suggested (Sect. 76).
The most remarkable instance of storage of food in the
stem is probably that of sago-palms, which contain an enor-
mous amount, sometimes as much as 800 pounds, of starchy
material in a single trunk. But the commoner plants of
temperate regions furnish plenty of examples of deposits
of food in the stem. As in the case of seeds and roots,
starch constitutes one of the most important kinds of this
reserve material of the stem, and since it is easier to detect
than any other food material which the plant stores, the stu-
dent will do well to spend time in looking for starch only.
Cut thin cross-section.s of twigs of some common deciduous tree
or shrub, in its early winter condition, moisten with iodine solution,
and examine for starch with a moderately high power of the micro-
scope. Sketch the section with a pencil, coloring the starchy por-
tions with blue ink, used with a mapping pen, and describe exactly
in what portions the starch is deposited.
97.	Storage in Underground Stems-------The branches and
trunk of a tree furnish the most convenient place in which
1 Not including most of the llowerless and very low and simple kinds.WORK OF THE STEM
83
to deposit food during winter to begin the growth of the
following spring. But in those plants which die down to
the ground at the beginning of winter the storage must be
either in the roots, as has been described in Sect. 49, or in
underground portions of tire stem.
Rootstocks, tubers, and bulbs seem to have been devel-
oped by plants to answer as storehouses through the win-
ter (or in some countries through the dry season) for the
reserve materials which the plant has accumulated during
the growing season. The commonest tuber is the potato,
and this fact and the points of interest which it repre-
sents make it especially desirable to use for a study of the
underground stem in a form most highly specialized for
the storage of starch and other valuable products.
98. A Typical Tuber: the Potato. — Sketch the general outline
of a potato, shoving the attachment to the stem from which it grew.1
Note the distribution of the “ eyes,” — are they opposite or alter-
nate ? Examine them closely with the magnifying glass and then with
the lowest power of the microscope. What do they appear to be?
If the potato is a stem, it may branch, — look over a lot of pota-
toes to try to find a branching specimen. If such a one is secured,
sketch it.
Note the little scale overhanging the edge of the eye and see if
you can ascertain what this scale represents.
Cut the potato across and notice the faint broken line which
forms a sort of oval figure some distance inside the skin.
Place the cut surface in eosin solution, allow the potato to stand
there for many hours, and then examine, by slicing off pieces parallel
to the cut surface, to see how far and into what portions the solution
has penetrated. Refer to the notes on the study of the parsnip
(Sect. 47) and see how far the behavior of the potato treated with
eosin solution agrees with that of the parsnip so treated.
1 Examination of a lot of potatoes will usually discover specimens with an
inch or more of attached stem.84
ESSENTIALS OF BOTANY
Cut a thin section at right angles to the skin and examine with
a high power. Moisten the section with iodine solution and exam-
ine again.
If possible, secure a potato which has been sprouting in a warm
place for a month or more (the loDger the better), and look near the
origins of the sprouts for evidences of the loss of material from the
tuber.
EXPERIMENT XII
Use of the Corky Layer.—Carefully weigh a potato, then pare
another larger one, and cut portions from it until its weight is made
approximately equal to that of the first one. Expose both freely to
the air for some days and reweigh. What does the result show in
regard to the use of the corky layer of the skin?
99.	Morphology of the Potato. — It is evident that in the
potato we have to do with a very greatly modified form of
stern. The corky layer of the bark is well represented, and
the loose cellular layer beneath is very greatly developed;
wood is almost lacking, being present only in the very narrow
ring which was stained by the red ink, but the pith is greatly
developed and constitutes the principal bulk of the tuber.
All this is readily understood if we consider that the tuber,
buried in and supported by the earth, does not need the
kinds of tissue which give strength, but only those which
are well adapted to store the requisite amount of food.
100.	Structure of a Bulb; the Onion. — Examine the external
appearance of the onion and observe the thin membranaceous skin
which covers it. This skin consists of the broad sheathing bases of
the outer leaves which grew on the onion plant during the summer.
Remove these and notice the thick scales (also formed from bases of
leaves as shown in Fig. 35) which make up the substance of the bulb.
Make a transverse section of the onion at about the middle and
sketch the rings of which it is composed. Cut a thin section from
the interior of the bulb, examine with a moderate power of the
microscope, and note the thin-walled cells of which it is composed.'WORK OF THE STEJI
85
Split another onion from top to bottom and try to find :
(a) The plate or broad flattened stem inside at the base (Fig. 34).
(i) The central bud.
(c)	The bulb-scales.
(d)	In some onions (particularly large, irregular ones) the bulblets
or side buds arising in the axes of the scales near the base.
Test the cut surface for starch.
101.	Plant-Foods in the Onion. — G-rape sugar is an impor-
tant substance among those stored for food by the plant.
It received its narnd- from the fact that it was formerly
obtained for chemical examination from grapes. Old, dry
raisins usually show little masses of whitish material
scattered over the shin "which are nearly pure grape sugar.
Commercially it is now manufactured on an enormous
scale from starch by boiling with diluted hydrochloric acid.
In the plant it is made from starch b)r processes as yet
imperfectly understood, and another sugar, called.maltose,
is made from starch in the seed during germination.
It may be readily shown by suitable experiments that
the onion contains both grape sugar and proteids.
102.	Tabular Review of Experiments. — [Continue the table from
Sect. 38.]
103.	Review Summary of Work of Stem.
fin young dicotyledonous stems.
Channels for upward movement j in dicotyledonous stems several
of water.....................1 years old.
[ in monocotyledonous stems.
Channels for downward move- f in dicotyledonous stems.
ment of water................\ in monocotyledonous stems.
Channels for transverse move-
ments.
r where stored.
Storage of plant-food .	... < kinds stored.
buses.CHAPTER IX
BUDS
104.	Structure of Buds.— While studying twigs in their
winter condition, as directed in Sects. 63, 64, the student
had occasion to notice the presence, position, and arrange-
ment of buds on the branch, but he was not called upon
to look into the details of their structure. The most nat-
ural time to do this is just before the study of the leaf is
begun, since leafy stems spring from buds, and the. rudi-
ments of leaves in some form must be found in buds.
105.	The Horse-Chestnut Bud. — Examine one of the lateral buds
on a twig in its winter or early spring condition.1
Make a sketch of the external appearance of the buds as seen
with a magnifying glass.	l
How do the scales with which it is
covered lie with reference to those	?
beneath them ?
Notice the sticky coating on the scales.	'
Are the scales opposite or alternate ?	2--i—6----------6--i—2
Remove the scales in pairs, placing
them in order on a sheet of paper, thus:
Make the distance from 1 to 1 as much	^
as 6 or 8 inches.
How many pairs are found ?	l
1 The best possible time for this examination is just as the buds are begin-
ning to swell slightly in the spring. The bud of buckeye or of cottonwood
will do for this examination, though each is on a good deal smaller scale than
the horse-chestnut bud. Buds may he forced to open early by placing twigs
in water in a very w'arm, light place for many weeks.
80BUDS
87
Observe as the scales are removed -whether the sticky coating is
thicker on the outside or the inside of each scale, and whether it is
equally abundant on all the successive pairs.
tVhat is the probable use of this coating?
Note the delicate veining of some of the scales as seen through
the magnifying glass. What does
this mean?
Inside the innermost pair are
found two forked woolly objects ;
what are these?
Compare with Figs. 48 and 55.
Their shape could be more readily
observed if the woolly coating were
removed.
Can you suggest a use for the
woolly coating?
Examine a terminal bud in the
same way in which you have just
studied the lateral bud.
Does it contain any parts not
found in the other?
What is the appearance of these
parts ?
What do they represent ?
If there is any doubt about then-
nature, study them further on a
horse-chestnut tree during and im-
mediately after the process of leaf-
ing out in the spring.
For comparison study at least
one of the following kinds of buds
in their winter or early spring con-
dition : hickory, butternut, beech,
ash, magnolia (or tulip tree), lilac,
balm of Gilead, cottonwood, cultivated cherry.1
Fig. 48. Dissected Bud of Buck-
eye (xEsculus macrostachya),
showing Transitions from Bud-
Scales to Leaves.
1 Consult the account of the mode of studying huds in Professor W. F. Ganong's
Teaching Botanist, pp. 208-210. If some of the buds are studied at home, pupils
will have a better chance to examine at leisure the unfolding process.88
ESSENTIALS OF BOTANY
106.	Nature of Bud-Scales. — The fact that
the bud-scales are in certain cases merely im-
perfectly developed leaves or leaf-stalks is often
clearly manifest from the series of steps con-
necting the bud-scale on the one hand with the
young leaf on the other, which may be found in
many opening buds, as illustrated by Fig. 48.
In other buds the scales are not imperfect leaves,
but the little appendages (stipules, Figs. 63, 64),
which occur at the bases of leaves. This kind
of bud-scale is especially well shown in the mag-
nolia and the tulip tree.
107.	Naked Buds. — All of the buds above
mentioned are winter buds, capable of living
through the colder months of the year, and are
scaly buds.
In the herbs of temperate climates, and even
in shrubs and trees of tropical regions, the buds
are often naked, that is, nearly or quite destitute
of scaly coverings (Fig. 49).
Make a study of the naked buds of any convenient
herb, such as one of the common “ geraniums ” (Pelar-
gonium), and record what you find in it.
108.	Position of Buds. — The distinction be-
tween lateral and terminal buds has already been
alluded to.
The plumule is the first terminal bud which
the plant produces. Lateral
Fig. 49. Tip of Branch of Allan- buds are usually a.rill am/, as
thus in Winter Condition, show-	,	• -n-	,, , .
ing very Large Leaf-Scars and sll0Wn in Flg' 58-that ls’ ^ey
nearly Naked Buds.	grow in the angle formed byBUDS
89
the leaf with the stem (Latin axilla, armpit). But not infre-
quently there are several buds grouped in some way about
a single leaf-axil, either one above the other, as in the
butternut (Fig. 51), or grouped side by side,, as in the red
maple, the cherry, and the
box-elder (Fig. 50).
In these cases all the
buds except the axillary
one are called accessory or
supernumerary buds.
109. Leaf-Buds and
Flower-Buds; the Bud an
Undeveloped Branch —
Such buds as the student
has so far examined for
himself are not large
enough to show in the most
obvious way the relation
of the parts and their real
nature.
The cabbage, however, is
a gigantic terminal bud which illustrates perfectly the struc-
ture of buds in general.
Examine and sketch a rather small, firm cabbage, preferably a red
one, 'which has been split lengthwise through the center and note:
(a)	The short, thick, conical stem ending in layers of rapidly
dividing cells, the growing apex, the source of new leaves, and length-
ening of the stem.
(b)	The crowded leaves which arise from the stem, the lower and
outer ones largest and most mature, the upper and innermost ones
the smallest of the series.
(c)	The axillary buds found in the angles made by some leaves
with the stem.
Fig. 50. Accessory Buds of Box-
Elder (Acer Negundo). (Magnified.)
A, front view of group: B, two
groups seen in profile. .90
ESSENTIALS OF BOTANY
Most of the buds so far considered were leaf-buds, that
js, the parts inside of the scales would develop into leaves,
and their central axes into steins; but
some were mixed buds, that is, they con-
tained both leaves and flowers in an
undeveloped condition.
Flower-buds contain the rudiments of
flowers only.
Sometimes, as in the black walnut and
the butternut, the leaf-buds and flower-
buds are readily distinguishable by their
difference in form, while in other cases,
as in the cultivated cherry, the differ-
ence in form is but slight.
The rings of scars about the twig,
shown in Fig. 54, mark the place where
the bases 'of bud-scales were attached.
A little examination of the part of the
twig which lies outside of this ring will
lead one to the conclusion that this
portion has all grown in the one spring
and summer since the bud-scales of that
particular ring dropped off. Following
Tig. 51. Accessory out this suggestion, it .is easy to reckon
(R^fduoecl^tternUt aSe any moderately old portion of
, a branch, since it is equal to the num-
/, leaf-scar; a:e, axil-	x
larybud; a, a', ac- ber of segments between the rings. In
cessory buds; t, ter- rapidly growing shoots of willow, pop-
lar, and similar trees, 5 or 10 feet of
the length may be the growth of a single year, while in the
lateral twigs of the hickory, apple, or cherry the yearly
increase may be but a fraction of an inch. Such fruitingBUDS
91
i
I
A
t
'
/
r
Fig. 52.
A, a pear leaf-bud in autumn ; B, a leafy shoot derived from A, as seen in
the middle of the following summer, with flower-bud at tip; C, the
fruit-spur, B, in autumn, after the fall of the leaves.
Fig. 53. Fmit-Bud of Pear (same as C, of Fig. 52), showing its
Development.
A, opening in spring; B, later, developing flowers and leaves; C, later
still: only one flower has produced a fruit, the rest having fallen off.
Below it is a lateral bud which will continue the spur next year.92
ESSENTIALS OF BOTANY
“ spurs ” as are shown in Fig. 52 are of little use in the
permanent growth of the tree, and poplars, elms, soft
maples, and other trees shed the
oldest of these every year. What-
ever the amount of this growth, it
is but the lengthening out and
development of the bud,
which may be regarded as
an undeveloped stem or
branch, with its internodes
so shortened that succes-
sive leaves seem almost to
Fit;. 54. A Slowly Grown
Twig of Cherry, Three
Inches Long and about
Ten Years Old. aa!i	m\m i|km
The pointed bud, l, is a leaf-	
bud ; the more obtuse	
accessory buds, /, /, are	nil r
flower-buds.	Wm
spring from the same point.	ill '*
In Figs. 52, 58 the com-	
plete history of a fruit-spur	A B CC
of the pear is shown, from
the leaf-bud which pro-
duced it to the pear which
it bears.
Fig. 55.
B, a twig of European elm ; A, a longi-
tudinal section of the buds of B (con-
siderably magnified), ax, the axis of
the bud which will elongate into a
shoot; sc, leaf-scars.
110. Vernation.—Procure a considerable number of buds which *
are just about to burst and others which have begun to open. Cut
each across with a razor or very sharp scalpel; examine first withBUDS
93
the magnifying glass and then with the lowest power of the micro-
scope. Pick to pieces other buds of the same kinds under the mag-
nifying glass, and report upon the manner in which the leaves are
packed away.
The arrangement of leaves in the bud is called verna-
tion; some of the principal modes are shown in Fig. 56.
1, 2, cherry; 3,4, European walnut; 5,6, snowball; 7, lady’s
mantle; 8, oxalis.
In the cherry the two halves of the leaf are folded
together flat, with the under surfaces outward; in the
walnut the separate leaflets, or parts of the leaf, are folded
flat and then grouped into a sort of cone ; in the snowball94
ESSENTIALS OF BOTANY
each half of the leaf is plaited in a somewhat fan-like
manner, and the edges of the two halves are then brought
round so as to meet; in the lady’s mantle the fan-like
plaiting is very distinct; in the wood sorrel each leaflet
is folded smoothly, and then the three leaflets are packed
closely side by side. All these modes of vernation and
many others have received accurate descriptive names by
which they are known to botanists.
111. Importance of Vernation. — The significance of ver-
nation is best understood by considering that there are
two important purposes to be served: the leaves must be
Fig. 57. Development of an Oxalis Leaf.
A, full-grown leaf; B, rudimentary leaf, the leaflets not yet evident;
C, more advanced stage, the leaflets appearing; JD, a still more
advanced stage. (B, C, and D considerably magnified.)
stowed as closely as possible in the bud, and upon begin-
ning to open they must be protected from too great heat
and dryness until they have reached a certain degree of
firmness. It may be inferred from Fig. 56 that it is
common for very young leaves to stand vertically. This
protects them considerably from the scorching effect of the
sun at the hottest part of the day. Many young leaves,
as, for instance, those of the silver-leafed poplar, the pear,
the beech, and the mountain ash, are sheltered and pro-
tected from the attacks of small insects by a coating ofBUDS
95
wool or down which they afterwards lose. Those of the
tulip tree are enclosed for a little time in thin pouches,
which serve as bud-scales, and are thus entirely shielded
from direct contact with the outside air.
112.	Dormant Buds. — Generally some of the buds on a
branch remain undeveloped in the spring, wThen the other
buds are beginning to grow, and this inactive condition
may last for many seasons. Finally the bud may die, or
some injury to the tree may destroy so many other buds
as to leave the dormant ones an extra supply of food, and
this, with other causes, may force them to develop and to
grow into branches.
Sometimes the tree altogether fails to produce buds at
places where they would regularly occur. In the lilac the
terminal bud usually fails to appear, and the result is con-
stant forking of the branches.
113.	Adventitious Buds-----Buds which occur in irregu-
lar places, that is, not terminal nor in or near the axils of
leaves, are called adventitious buds; they may spring from
the roots, as in the silver-leafed poplar, or from the sides
of the trunk, as in our American elm. In many trees, for
instance willows and maples, they are sure to appear after
the trees have been cut back. Willows and poplars are
thus cut back or pollarded, as shown in Plate III, in order
to cause them to produce a large crop of slender twigs
suitable for basket-making or for withes.
Leaves rarely produce buds, but a few kinds do so
when they are injured. Those of the bryophyllum, a
plant allied to the garden live-for-ever, when they are
removed from the plant while they are still green and
fresh, almost always send out buds from the margin.
These do not appear at random but are borne at the96
ESSENTIALS OF BOTANY
notches in the leaf-margin and are accompanied almost
from the first by minute roots.
Pin up a bryopliyllurn leaf on the wall of the room or
lay it on the surface of moist earth, and follow day by
day the formation and development of the buds which it
may produce.
This plant seems to rely largely upon ieaf-budding to
reproduce itself, for in a moderately cool climate it rarely
flowers or seeds, but drops its living leaves freely, and from
each such leaf one or several new plants may be produced.
114. Review Summary of Chapter IX.
Make a sketch of Fig. 58 as it looked in .Tune of the same sum-
mer ; also as it would look the following June (Fig. 58 represents the
autumn condition). Sketch the twigs of Fig. 24 and Fig. 25 as seen
one year later.
Coverings.
Contents .	.
Classes of buds as regards
position..................Plate III. Pollarded Poplars.CHAPTER X
LEAVES
115. The Elm Leaf. — Sketch the leafy twig of elm that is sup-
plied to you.1 Report- on the following points :
(a) How many rows of leaves?
(ft) How much overlapping of leaves when the twig is held with
the upper sides of the leaves toward you? C'an you suggest a reason
for this? Are the
spaces between the
edges of the leaves
large or small com-
pared with the leaves
themselves ?
Pull off a single
leaf and make a very
1 Any elm will answer
the purpose. Young
strong shoots which ex-
tend horizontally are
best, since on these leaves
are most fully developed
and their distribution
along the twig appears
most clearly. Other good
kinds of leaves with
which to begin the study,
if elm leaves are not
available, are those of
beech, oak, willow, peach, cherry, apple. Most of the statements and direc-
tions above given would apply to any of the leaves just enumerated. If this
chapter is reached too early in the season to admit of suitable material being
procured for the study of leaf arrangement, that topic may be omitted until
the leaves of forest trees have sufficiently matured.
9798
ESSENTIALS OF BOTANY
careful sketch of its under surface, about natural size. Label the
broad expanded part the blade, and the stalk by which it is attached
to the twig, leafstalk or petiole.
Study the outline of the leaf and answer these questions:
(a)	What is the shape of the leaf taken as a whole ? (See Appen-
dix.) Is the leaf bilaterally symmetrical, i.e., is there a middle line
running through it lengthwise, along which it could be so folded that
the two sides would precisely coincide?
(b)	What is the shape of the tipi of the
leaf? (See Appendix I.)
(c)	Shape of the base of the leaf? (See
Appendix I.)
(d)	Outline of the margin of the leaf?
(See Appendix I.)
Notice that the leaf is traversed length-
wise by a strong midrib and that many so-
called veins run from this to the margin. Are
these veins parallel ? Hold the leaf up towards
the light and see how the main veins are con-
nected by smaller reinlets. Examine with your
glass the leaf as held to the light and make
a careful sketch of portions of one or two
veins and the intersecting veinlets. IIow is
the course of the veins shown on the upper
surface of the leaf?
Examine both surfaces of the leaf with the
glass and look for hairs distributed on the
surfaces. Describe the manner in which
the hairs are arranged.
The various forms of leaves are classed and described
by botanists with great minuteness,1 not simply for the
study of leaves themselves, but also because in classify-
ing and describing plants the characteristic forms of the
leaves of many kinds of plants form a very simple and
ready means of distinguishing them from each other and
1 See Kerner and Oliver’s Natural History of Plants, Vol. I, pp. 623-637
Fig. 59. Netted Vein-
ing (pinnate) in Leaf
of Foxglove.LEAVES
99
identifying them. The student is not expected to learn the
names of the several shapes of leaves as a whole or of their
bases, tips, or margins, except in those cases in which he
needs to use and apply them.
Many of the words used to
describe the shapes of leaves are
equally applicable to the leaf-
like parts of flowers.
Fig. 60. Netted Veining (pal-
mate) in Leaf of Melon.
116. The Maple Leaf. — Sketch the
leafy twig.
Are the leaves arranged in rows
like those of the elm ? How are they
arranged ?
How are the petioles distorted from
their natural positions to bring the
proper surface of the leaf upward toward the light?
Do the edges of these leaves show larger spaces between them
than the elm leaves did, i.e., would a spray of maple intercept the
sunlight more or less perfectly than a
spray of elm ? Pull off a single leaf and
sketch its lower surface, about natural
Of the (wo main parts whose names
have already been learned (blade and
petiole), which is more developed in the
maple than in the elm leaf?
Describe :
(a) The shape of the maple leaf as a
whole. To settle this, place the leaf on
paper, mark the positions of the extreme
points, and connect these by a smooth
line.
(1) Its outline as to main divisions;
of what kind and how many?
(c) The detailed outline of the mar-
gin. (See Appendix I.)
Fig. 61. Pinnately Divided
Leaf of Celandine.
The blade of the leaf is discon-
tinuous, consistingof several
portions, between which are
spaces in which one part of
thebladehasbeen developed.100
ESSENTIALS OF BOTANY
Compare the mode of veining or venation of the elm and the
maple leaf by making a diagram of each.
These leaves agree in being netted-veined, i.e., in having veinlets
that join each other at many angles, so as to form a sort of delicate
lace-work, like Figs. 59 and 60.
They differ, however, in the arrange-
ment of the principal veins. Such a leaf
as that of the elm is said to be feather-
veined, or pinnately veined.
The maple leaf, or any leaf with closely
similar venation, is said to be palmately
veined. Describe the difference between
the two plans of venation.
117. Relation of Venation to
Shape of Leaves.—As soon as the
student begins
to observe leaves
somewhat
widely, he can
hardly fail to
notice that there
is a general rela-
tion between the
plan of venation and the shape of the
leaf. How may this relation be stated?
In most cases the principal veins follow
at the outset a pretty straight course, a
fact for which the student ought to be
able to give a reason after he has per-
formed Exp. xvi.
On the whole, the arrangement of the
veins seems to be such as to stiffen
the leaf most in the par.ts that need most support, and to
reach the region near the margin by as short a course as
Fig. 62. Palmately Divided
Leaf of Buttercup.
Fig. 63. Leaf of
Apple, with Stipules.LEAVES
101
Pansy, with Leaf-
like Stipules.
possible from the end of the petiole, to
distribute water quickly throughout.
118. Stipules.—Although they are
absent from many leaves and disappear
early from others, stipules often form a part
(sometimes the largest and most useful por-
tion) of the leaf.1 When present they are
sometimes found as little bristle-shaped
objects at the base of the leaf, as in the
apple leaf (Fig. 63), Em. 64. Leaf of
sometimes as leaf-
like bodies, for ex-
ample in the pansy (Fig. 64), and in
many other forms, one of which is
that of spinous
appendages, as
shown in the
common locust
(Fig. 68).
119. Parallel-
Veined Leaves.
— The leaves of
many great groups of plants, such as
the lilies, the sedges, and the grasses,
are commonly parallel-veined, that is,
with the veins running nearly par-
allel, lengthwise through the blade,
as shown in Fig. 65, or with parallel
Eio. 65. Parallel-Veined
Leaf of Solomon’s Seal.
1 Unless the elra twigs used in the previous
study were cut soon after the unfolding of the
leaves in spring, the stipules may not have been
left in any recognizable shape.
Fig. 66. Parallel Vein-
ing in Canna. Veins
running from midrib
to margin.102
ESSENTIALS OF BOTANY
veins proceeding from a midrib and thence extending to
the margin, as shown in Fig. 66.
120. Occurrence of Netted or Parallel Veining. — The stu-
dent has already, in his experiments on germination, had
an opportunity to observe the difference in mode of vein-
ing between the
leaves of some
dicotyledonous
plants and those
of monocotyled-
onous plants.-
This unlikeness is
somewhat general
throughout these
groups of flower-
ing plants. What
is the difference?
The polycoty-
ledonous pines,
spruces, and other
coniferous trees
have leaves with
but a single vein,
or two or three
Fig. 67. The Fall of the Horse-Chestnut Leaf. Parallel ones’ but
in their case the
veining could hardly be other than parallel, since the needle-
like leaves are so narrow that no veins of any considerable
length could exist except in a position lengthwise of the leaf.
The fact that a certain plan of venation is found mainly
in plants with a particular mode of germination, of stem
structure, and of arrangement of floral parts, is but oneLEAVES
103
of the frequent cases in botany in which the structures of
plants are correlated in a way which is not easy to explain.
No one knows why plants with two
cotyledons usually have netted-veined
leaves, but many such facts as this
are familiar to every botanist.
121. Simple and Compound Leaves.
— The leaves so far studied are sim-
ple leaves, that is, leaves of which the
blades are more or less entirely united
into one piece. But
while in the elm
the margin is cut
in only a little way,
in some maples it
is deeply cut in to-
ward the bases of
the veins. In some
leaves the gaps be-
tween the adjacent
portions extend all
the way down to
the petiole (in pal-
mately veined
leaves) or to the
midrib (in pin-
nately veined ones). Such divided leaves
are shown in Figs. 61 and 62.
In still other leaves, known as com-
pound leaves, the petiole, as shown in
Fig. 67 (palmately compound), or the midrib, as shown in
Fig. 68 (pinnately compound), bears what look to be separate
Fig. 68. Pinnately Com-
pound Leaf of Locust,
with Spines for
Stipules.

Fig. 69. Pinnately
Compound Leaf of
Pea. A tendril
takes the place of
a terminal leaflet.104
ESSENTIALS OF BOTANY
leaves. These differ in their nature and mode of origin
from the portions of the blade of a divided leaf. One
result of this difference appears in the fact that some time
before the whole leaf is ready to fall in autumn, the leaflets
of a compound leaf are seen to be jointed at their attach-
ments. In Fig. 67 the horse-chestnut leaf is shown at the
time of falling, with some of the leaflets already disjointed.
That a compound leaf, in spite of the joints of the sepa-
rate leaflets, is really only one leaf is shown: (1) by the
absence of buds in the axils of leaflets (see Fig. 68); (2) by
the horizontal arrangement of the blades of the leaflets,
without any twist in their individual leaf-stalks; (3) by
the fact that their arrangement on the midrib does not
follow any of the systems of leaf arrangement on the stem
(Sect. 124). If each leaflet of a compound leaf should
itself become compound, the result would be to produce a
twice compound leaf. Fig. 77 shows that of an acacia.
122. Review Summary of Leaves.1
Parts of a model leaf..........................
Classes of netted-veined leaves................
Classes of parallel-veined leaves..............
Relation of venation to number of cotyledons .
1
o
3
f 1

I "
Compound leaves; types dependent on arrangement of J 1.
leaflets .	................. .................1 i>.
Once, twice, or three times compound ..........
1 Illustrate by sketches if possible.CHAPTER XI
ECOLOGY OF LEAVES
123.	Ecology. — Plant ecology includes all that portion
of botany which has to do with the way in which plants
get on with their animal and plant neighbors, and espe-
cially the way in which they adjust themselves to the na-
ture of the soil and climate in which they live. Ecology, in
short, discusses the relations of plants to their surround-
ings or environment. A good deal of what has been said
in previous chapters about such topics as variation of roots
for life in air or water, parasitic plants, the occurrence of
winter bud-scales, is really ecological botany, although it
is not so designated in the sections where it occurs.
124.	Leaf Arrangement.1 — As bas been learned from the
study of the leafy twigs examined, leaves are quite gener-
ally arranged so as to secure the best possible exposure to
the sun and air. This, in the vertical shoots of the elm,
the oak (Fig. 70), the apple, beech, and other alternate-
leaved trees, is not inconsistent with their spiral arrange-
ment of the leaves around the stem. In horizontal twigs
and branches of the elm, the beech (Fig. 71), the chestnut,
the linden, and many other trees and shrubs, the desired
effect is secured by the arrangement of all the leaves in
two flat rows, one on each side of the twig. The rows
are produced, as it is easy to see on examining such a
1 See Kerner and Oliver’s Natural History of Plants, Vol. I, pp. 396^424.
105106
ESSENTIALS OF BOTANY
leafy twig, by a twisting about of the petioles. The adjust-
ment in many opposite-leavgd trees and shrubs consists
in having each pair of leaves cover the spaces between
the pair below it, and sometimes in
the lengthening of the lower peti-
oles so as to bring the blades of
the lower leaves outside those of
the upper leaves. Examination
of Figs. 72 and 73 will make the
matter clear.
The student should not fail to
study the leafage of several trees
of different kinds on the growing
tree itself, and in climbers on walls,
Fig. 70. Le.if Airangement an(j tQ notqce pow circumstances
of tlie Oak.
modify the position of the leaves.
Maple leaves, for example, on the ends of the branches are
arranged much like those of the horse-chestnut, but they
are found to be arranged more nearly flatwise along the
inner portions of the branches,
that is, the portions nearer the
tree. Figs. 74 and 75 show the
remarkable difference in arrange-
ment in different branches of the
Deutzia, and equally interesting
modifications may be found in
alternate-leaved trees, such as
the elm and the cherry.	Fig. 71. Leaf Arrangement
125. Leaf-Mosaics. - In very of EuroPean Bee°h-
many cases the leaves at the end of a shoot are so arranged
as to form a rather symmetrical pattern, as in the hoi-se-
chestnut (Fig. 72). When this is sufficiently regular,Plate IV. Leaf Mosaic, Japanese Ivy.ECOLOGY OF LEAVES
107
usually with the space between the leaves a good deal
smaller than the areas of the leaves themselves, it is called
a leaf-mosaic.
Many of the most
interesting leaf-
groups of this sort
(as in the figure
above mentioned)
are found in the
so-called root-
leaves of plants.
Good examples of
these are the dan-
.delion, chicory,
fall d andelion, Fig. 72. Leaf Arrangement of Horse-Chestnut
th i s 11 e, h a w k-	011 Vertical Shoots <top view>-
weed, pyrola, and plantain. How are the leaves of these
plants kept from
shading each
other ?
126. Much-
Divided Leaves. —
Not infrequently
leaves are cut into
slender fringe-like
divisions, as in the
carrot, tansy,
southernwood,
Fig. 73. Leaf Arrangement of Horse-Chestnut	,
on Vertical Shoots (side view).	wormwood, yar-
row, dog-fennel,
cypress-vine, and many other common plants. This kind
of leaf seems to be adapted to offer considerable surface to108
ESSENTIALS OF BOTANY
the sun without cutting off too much light from other
leaves underneath. Such a leaf is in much less danger of
being torn by severe winds than are broader ones with
undivided margins. The same purposes are served by
compound leaves with very many small leaflets, such as
those of the honey-locust, mimosa acacia (Fig. 77), and
Fig. 74. Opposite Leaves of Deutzia1 (from the same shrub as Fig. 75),
as arranged on a Horizontal Branch.
other trees and shrubs of the pea family. What kind of
shade is produced by a horse-chestnut or a maple tree
compared with that of a honey-locust or an acacia?
127. Daily Movements of Leaves. — Many compound
leaves have the power of changing the position of their
leaflets to accommodate themselves to varying conditions
of light and temperature. Some plants have the power
of directing the leaves or leaflets edgewise towards the
sun during the hottest parts of the day, allowing them to
1 Deutzia crenata.ECOLOGY OF LEAVES
109
extend their surfaces more nearly in a horizontal direction
during the cooler hours.
The so-called “sleep” of plants has long been known,
but this subject has been most carefully studied rather
recently. The wood sorrel,
or oxalis, the common bean,
clovers, and the locust tree
are some of the most fa-
miliar of the plants whose
leaves assume decidedly
different positions at night
from those which they
occupy during the day.
Sometimes the leaflets rise
at night, and in many
instances they droop, as
in the red clover (Fig. 76) Fig. 75. Opposite Leaves of Deutzia,
I	•	/Xr»‘	as arranged on a Vertical Branch,
and the acacia (hig. 77).	&
One useful purpose, at any rate, that is served by the leaf’s
taking the nocturnal position is protection from frost. It
has been proved experi-
mentally that when part
of the leaves on a plant
are prevented from as-
suming the folded posi-
tion, while others are
allowed to do so, and the
Fig. 76. A Leaf of Red Clover.	plant is then exposed
At the left, leaf by day; at the right,	during a frosty night,
the same leaf asleep at night.	. i x i j j
F &	the iolded ones may
escape while the others are killed. Since many plants in
tropical climates fold their leaves at night, it is certain110
ESSENTIALS OF BOTANY
that this movement has other purposes than protection
from frost, and probably there is much yet to be learned
about the uses of leaf movements.
128. Vertically Placed Leaves.—Very many leaves, like
those of the iris (Fig. 32), always keep their principal sur-
faces nearly vertical, thus receiving the morning and even-
ing sun upon their faces, and the noonday sun (which is
so intense as to injure them when received full on the
A
Fig. 77. A Leaf of Acacia.
A, as seen by day; B, the same leaf asleep at night.
surface) upon their edges. This adjustment is most per-
fect in the compass-plant of the prairies of the Mississippi
basin. Its leaves stand very nearly upright, many with
their edges just about north and south (Fig. 78), so that
the rays of the midsummer sun will, during every bright
day, strike the leaf-surfaces nearly at right angles during
a considerable portion of the forenoon and afternoon,
while at midday only the edge of each leaf is exposed
to the sun.ECOLOGY OF LEAVES
111
Fig. 78. Leaves standing nearly Vertical in Compass-Plant
(Silphium laciniatum).
A, view from east or west; B, from north or south.
129. Movements of Leaves and Stems toward or away
from Light (Heliotropic Movements)-----The student doubt-
less learned from his experiments with seedling plants
that their stems tend to seek light. The whole plant112
ESSENTIALS OF BOTANY
above ground usually bends toward the quarter from which
the strongest light comes. Such movements are called
heliotropic from two Greek words which mean turning
toward the sun. How do the plants in a window behave
with reference to the light ?
How do Young Shoots of English Ivy bend with Reference to Light?
— Place a thrifty potted plant of English ivy before a small window,
e.g., an ordinary cellar window, or in a large covered box painted
dull black within and open only on the side toward a south window.
After some weeks note the position of the tips of the shoots.
Explain the use of their movements to the plant.
130.	Positive and Negative Heliotropic Movements; how
produced. — Plants may bend either toward or away from
the strongest light. In the former case they are said to
show positive heliotropism, in the latter negative heliotro-
pism. In both cases the movement is produced by unequal
growth brought about by the unequal lighting of different
sides of the stem. If the less strongly lighted side grows
faster, what kind of heliotropism results ? If the more
strongly lighted side grows faster, what kind of heliotro-
pism results? How would a plant behave if placed on a
revolving table before a window and slowly turned during
the hours of daylight?
131.	Review Summary of Chapter XI.
EXPERIMENT XIII
Leaf arrangement
Movements of leaves .... Uses of.
Compass-plants.
Heliotropic bending of stems . j I,os't ''e'
Heliotropic bending of stems .
negative.CHAPTER xrr
ECOLOGY OF LEAVES (continued)
132.	Plant Formations.—A little observation is enough to
show the beginner in botany that plants are not scattered
indiscriminately over the surface of the earth, but that
hills, meadows, fresh-water marshes, salt marshes, and many’'
other kinds of localities have their characteristic assem-
blages of plants. Any such group is called a plantformation.
It may consist of only a few species, but more commonly
comprises several score or even a hundred or more of
flowering plants (seed-plants) alone, not to speak of the
multitudes of lower forms, such as ferns, mosses, and
simpler microscopic plants.
It will generally be found that the members of a plant
formation are growing under what is, for them, nearly the
best environment, since they -cannot usually be made to
exchange places with each other. If a square mile of land
in Louisiana were to be planted with Minnesota species,
and a square mile in Minnesota with Louisiana species,
it is very improbable that either tract, if left to itself,
would long retain its artificial flora. To this rule there
are, however, important exceptions.
133.	Ecological Classification of Plants. — The ordinary
classification of plants is based, as far as possible, on their
actual relationships to each other. But when plants are
classified ecologically they are grouped according to their
113114
ESSENTIALS 'OF BOTANY
relations to the world about them. They may, therefore,
be gathered into as many (or more than as many) different
groups as there are important factors influencing their
modes of life. We may classify plants as light-loving and
darkness-loving, as requiring free oxygen and not requir-
ing it, and so on.
The most important consideration in classifying seed-
plants on ecological grounds is based on their require-
ments in regard to water. Grouped with reference to this
factor in their life, all plants may be classed as :
,(1) Hydrophytes, or water-loving plants.
(2)	Xerophytes, or drought-loving (or perhaps drought-tolerating)
plants.
(3)	Mesophytes, or plants which thrive best with a moderate supply
of water.
These three classes do not fully express all the relations
of plants to the water supply, so two others are found
convenient.
(4)	Tropophyles, or seasonal plants which are hydrophytes during
part of the year and xerophytes during another part.1
(5)	Halophytes, or salt-marsh plants and “ alkali ” plants, species
which can flourish in a very saline soil.
134. Leaves in Relation to Ecological Classes. —Although
the roots and stems of plants which belong to extremely
specialized ecological types offer many modifications which
adapt them to the kind of life which they have to lead, yet
the leaves are still more important in their adaptations.
A good botanist can often decide merely by looking at the
1 The plants which E. Warming, one of the foremost authorities, classes
as mesophytes are many of them grouped by another great authority,
A. F. W. Schimper, as tropophytes.Photograph furnished by the Field Museum of Natural History.
Plate V. An Opening in a Tropical Forest.ECOLOGY OF LEAVES
115
leaf of an unknown plant whether it is an alpine, a desert,
or a seaside species. This is because of the importance
of leaves in disposing of the water taken into the plant
(Chapter XIII).
135.	Leaves of Hydrophytes.—Not nearly all hydrophytes
are aquatics, but some merely prefer very moist soil or
moist air. Of the truly aquatic species some have their
leaves wholly submerged;
others, such as the duck-
weeds and pond-lilies, have
them floating; and still
others, like the sedges, the
bur reeds, the cat-tails, and
the pickerel weeds, have
their leaves freely exposed
to the air. A few plants
have both water leaves and
air leaves (Fig. 79). It is
generally supposed that the
thread-like form of sub-
merged leaves in so many
species of aquatics gives
them greater capacity to
absorb dissolved gases from the water which surrounds them.
136.	Leaves of Xerophytes. — In regions where the great-
est dangers to vegetation arise from long droughts and
the excessive heat of the sun, the leaves of plants usu-
ally offer much less surface to the sun and air than is the
case in temperate climates, as shown in the Australian
blackberry (Fig. 80). Sometimes the blade of the leaf is
absent and the expanded petiole answers the purpose of a
blade, or, again, foliage leaves are altogether lacking, as in
Fig. 79. Submerged and Aerial
Leaves of a European Crowfoot
(Ranunculus Purshii). The leaf
with thread-like divisions is the
submerged one.116
ESSENTIALS OF BOTANY
the cactuses (Fig. 81), and the green outer layers of the
stem do the work of the leaves.
137. Rolled-Up Leaves. — Leaves which receive but a
scanty supply of water are often protected from losing it
Fig. 80. Xerophytic Leaves of Australian Blackberry.
I, leaflets reduced in many cases to bare midribs, in other cases showing a bit
of blade at the end; P, petiole.
too rapidly by being rolled up, so that the evaporating,
t.e., stomata-containing, surface is on the inside of the
roll. Sometimes, as in the crow-berry (Fig. 82). the curledECOLOGY OF LEAVES
117
Fig. 81. Melon-Cactus.
Fig. 82. Cross-Section of Rolled-Up Leaf of Crow-Berry
(.Empetrum nigrum). (Magnified.)118
ESSENTIALS OF BOTANY
condition is permanent. In other plants, as in Indian
corn, the leaf rolls up when the weather is very dry and
unrolls again when it receives a better supply of water.
138.	Fleshy Leaves.—
Many xerophytes and a
still larger proportion of
halophytes have thick,
fleshy leaves, sometimes
thick at the base and
tapering to a point often
nearly cylindrical in
form. The common
portulaca, the so-called
“ice-plants,” and the
century-plant offer fa-
miliar examples of fleshy
leaves. Leaves of this
form stand exposure to
the hottest sunshine,
even when the plant is
scantily supplied with
water.
139.	Leaves of Meso-
phytes.—The great
Fio. 83. Common Pitcher-Plant majority of foliage
(Sanacenia purpurea).	leaves, such as those of
At the right one of the pitcher-like leaves m0st common garden
is shown in cross-section.	..
herbs, grasses, clovers,
and so on, belong to this class. They are neither remark-
ably thick nor thin, expanded nor scanty in surface, and
they show no such special adaptations as rolling up to
avoid the parching effect of excessive sunshine.Photograph by William Trvleuse.
Plate VI. Tree Yucca in a California Desert.ECOLOGY OF LEAVES
119
Eig. 84.
Sundew (Drosera rotundifolia).120
ESSENTIALS OF BOTANY
140. Carnivorous Plants. — In the
ordinary pitcher-plants (Fig. 83) the
leaf appears in the shape of a more or
less hooded pitcher. These pitchers
are usually partly filled with water,
and in this water very many drowned
and decaying insects are commonly
to be found. The insects have flown
or crawled into the pitcher, and, once
inside, have been unable to escape on
account of the dense growth of bristly
hairs about the mouth, all pointing
inward and downward. How much
the common American pitcher-plants
depend for nourishment on the drowned insects in the
pitchers is not definitely known, but it is certain that some
of the tropical species
require such food.1
In other rather com-
mon plants, the sun-
dews, insects are
caught by a sticky
secretion which pro-
ceeds from hairs on the
leaves. In one of the
commonest sundews
the leaves consist of a LiG. gg Leaves of Sundew. (Some-
roundish blade borne	what magnified.)
On a moderately long The one at the left has all its tentacles closed
over captured prey; the one at the right
i Where the Sarracenia is has only half of them thus closed,
abundant it will be found in-
teresting ami profitable to make a careful class study of its leaves. See
Geddes’ Chapters iu Modern Botany, Chapters I aud II.
Fig. 85. Blade of Leaf
of Sundew. (Some-
what magnified.)ECOLOGY OF LEAVES
121
petiole. On the inner surface and round the margin of the
blade (Fig. 85) are borne a considerable number of short
bristles, each terminating in a knob which is covered with
a clear, sticky liquid. When a smdll insect touches one
of the sticky knobs, he is
held fast and the hairs at
once begin to close over
him, as shown in Fig. 86.
Here lie soon dies and
then usually remains for
many days, while the leaf
pours out a juice b}' which
the soluble parts of the
insect are digested. The
liquid containing the
digested portions is then
absorbed by the leaf and
contributes an important
part of the nourishment
of the plant, while the un-
digested fragments, such
as legs, wing-cases, and so
on, remain on the surface	Fig. 87. Venus' Flytrap,
of the leaf or may drop
off after the hairs let go their hold on the captive insect.
In the Venus' flytrap, which grows in the sandy regions
of eastern North Carolina, the mechanism for catching
insects is still more remarkable. The leaves, as shown in
Fig. 87, terminate in a hinged portion which is surrounded
by a fringe of stiff bristles. On the inside of each half of
the trap grow three short hairs. The trap is so sensitive
that when these hairs are touched it closes rather rapidly122
ESSENTIALS OF BOTANY
and very generally succeeds in capturing the fly or other
insect which has sprung it. The imprisoned insect then
dies and is digested, somewhat as in the case of those
caught by the sundew, after which the trap reopens and is
ready for fresh captures.
141.	Object of catching Animal Food. — It is easy to
understand why a good many kinds of plants have taken
to catching insects and absorbing the digested products.
Carnivorous, or flesh-eating, plants belong usually to one
of two classes as regards their place of growth: they are
bog-plants or air-plants. In either case their roots find it
difficult to secure much nitrogen-containing food, —that is,
much food out of which proteid material can be built up.
Animal food, being itself largely proteid, is admirably
adapted to nourish the growing parts of plants, and those
which could develop insect-catching powers would stand
a far better chance to exist as air-plants or in the thin,
watery soil of bogs than plants which had acquired no
such resources.
142.	Destruction of Plants by Animals. — All animals
are supported directly or indirectly by plants. In some
cases the animal secures its food without much damage
to the plant on which it feeds. Browsing on the lower
branches of a tree may do it little injury, and grazing
animals, if not numerous, may not seriously harm the
pasture on which they feed. Fruit-eating animals may
even be of much service by dispersing seeds. But seed-
eating birds and quadrupeds, animals which, like the hog,
dig up fleshy roots, rootstocks, tubers, or bulbs, and eat
them, or animals which, like the sheep, graze so closely as
to expose the roots of grasses or even of forest trees to be
parched by the sun, destroy immense numbers of plants.ECOLOGY OF LEAVES
123
So too with leaf-eating insects and snails, which consume
great quantities of leaves.
143. Plants of Uneatable Texture-----Whenever tender
and juicy herbage is to be had, plants of hard and stringy
texture are left untouched. In pastures there grow such
perennials as the bracken fern and the hardhack of New
England and the iron weed and vervains	.
of the Central States, which are so harsh
and woody that the hungriest browsing
animal is rarely, if ever, seen to molest
them. Still other plants, like the knot-
grass and cinquefoil of our dooryards,
Eig. 88. Spiny Leaves of Barberry.
are doubly safe from their growing so close to the ground
as to be hard to graze and from their woody and unpala-
table nature. The date-palm (which can easily be raised
from the seed in the schoolroom or the laboratory) is an
excellent instance of the same uneatable quality found in
a tropical or subtropical plant.
144. Plants with Weapons for Defense.1— Multitudes of
plants, which might otherwise have been subject to the
i See Kerner and Oliver’s Natural History of Plants, Vol. I, p. 430.124
ESSENTIALS OF BOTAXY
attacks of grazing or browsing animals, have acquired what
have with reason been called weapons. Among the most
conspicuous of these are thorns, which are often modified
branches. Thorns, which are really modified leaves, are
very perfectly exemplified in the barberry (Fig. 88). It
is much commoner to find the leaf extending its midrib or
its veins out into spiny points, as the thistle does, or bear-
mon locust (Fig. 91) the
^tjtjbwrtuin bud, or the very young
airopurpureum). shoot which proceeds from
it, is admirably protected by the jutting thorn on either side.
145. Pointed, Barbed, and Stinging Hairs.—Needle-
pointed hairs are an efficient defensive weapon of many
plants. Sometimes these hairs are roughened, like those
of the bugloss (Fig. 92, b); sometimes they are decidedly
barbed. If the barbs are well developed, they may cause
the hairs to travel far into the flesh of animals and cause
intense pain. In the nettle (Fig. 92, a) the hairs are
efficient stings, with a brittle tip, which on breaking off
exposes a sharp, jagged tube full of irritating fluid. These
tubular hairs, with their poisonous contents, will be found
sticking in the skin of the hand or the face after incau-
tious contact with nettles, and the violent itching which
follows is only too familiar to most people.
ing spines or prickles on
its midrib, as is the case
with the nightshade
shown in Fig. 89, and
with so many roses.
Stipules are not infre-
quently found occurring
as thorns, and in our com-ECOLOGY OF LEAVES
125
146. Cutting Leaves. — Some grasses and sedges are
generally avoided by cattle because of the sharp cutting
edges of their
leaves, which will
readily slit the
skin of one’s hand
if they are drawn
rapidly through
the fingers. Un-
der the microscope
the margins of
Fig. 00. Euphorbia splendens.
The spines are dead and dry
stipules.

di
f^
such leaves are seen to be
regularly and thickly set with
sharp teeth like those of a saw
' (|	(FiS- 92, c’ **)•
i	147. Offensive or Poisonous
Plants. — A disgusting smell is one of the
common safeguards which keep plants from
being eaten. The dog-fennel, the hound’s-
tongue (Cynoglossum), the Martynia, and
the tomato-plant are common examples of
rank-smelling plants which are offensive
to most grazing animals and so are let
alone by them. Oftentimes, as in the case
of the jimson weed (Datura), the tobacco-
plant, and the poison hemlock (Conium),
the smell serves as a warning of the poi-
sonous nature of the plant. A bitter, nauseating, or biting
taste protects many plants from destruction by animals.
Fig. 91. Thom
Stipules of
Locust.126
ESSENTIALS OF BOTANY
Buckeye, horse-chestnut, and buckthorn leaves are so
hitter that browsing animals and most insects let them
alone. Tansy, ragweed, boneset, southernwood, and worm-
wood are safe for the same reason. The nauseous taste of
Fig. 92. Stinging Hairs and Cutting Leaves. (All much magnified.)
a, stinging hairs on leaf of nettle; b, bristle of the bugloss; c, barbed margin
of a leaf of sedge; d, barbed margin of a leaf of grass.
many kinds of leaves and stems, such as those of the potato,
and the fiery taste of horse-radish, make these substances
uneatable for most animals.
Poisonous plants are usually shunned by grown-up
animals, though the young ones will sometimes eat such
plants and may be killed by them.CHAPTER XIII
MINUTE STRUCTURE OF LEAVES; FUNCTIONS OF
LEAVES
148.	Leaf of Lily. — A good kind of leaf with which to
begin the study of the microscopical structure of leaves
in general is that of the lily.1
149.	Cross-Section of Lily Leaf. — The student should first exam-
ine with the microscope a cross-section of the leaf, that is, a very
thin slice, taken at right angles to the upper and under surfaces and
to the veins. This will show :
(a)	The upper epidermis of the leaf, a thin, nearly transparent
membrane.
(b)	The intermediate tissues.
(c)	The lower epidermis-
Use a power of from 100 to 200 diameters. In order to ascertain
the relations of the parts and to get their names, consult Fig. 93.
Your section is by no means exactly like the figure ; sketch it. Label
properly all the parts shown in your sketch.
Are any differences noticeable betw'een the upper and the lower
epidermis? between the layers of cells immediately adjacent to
each ?
150.	Under Surface of Lily Leaf. — Examine with a power of 200
or more diameters the outer surface of a piece of epidermis from the
lower side of the leaf.2 Sketch carefully, comparing your sketch
with Fig. 94, B, and labeling it to agree with that figure.
1	Any kind of lily will answer.
2	The epidermis may be started with a sharp knife, then peeled off with
Small forceps, and mounted in water for microscopical examination.
127128
ESSENTIALS OF BOTANY
151. Stomata. — A stoma is a microscopic pore or slit
in the epidermis. It is bounded and opened and shut
by guard-cells (Fig. 94, g), usually two in number. These
Fig. 93. Vertical Section of the Leaf of the Beet. (Much magnified.)
e, epidermis; p, palisade-cells (and similar elongated cells); r, cells filled
with red cell-sap; i, intercellular spaces; a, air spaces communicating
with the stomata; st, stomata, or breathing pores.
are generally somewhat kidney-shaped and become more
or less curved as they are fuller or less full of water (see
Sect. 158).
In the case of an apple tree, where the epidermis of the
lower surface of the leaf contains about 24,000 stomata toMINUTE STRUCTURE OF LEAVES
129
the square inch, or the black walnut, with nearly 300,000
to the square inch, the total number on a tree is incon-
ceivably large.
152. Uses of the Parts examined. — It will be most con-
venient to discuss the uses of the parts of the leaf a little
later, but it will
make matters sim-
pler to state at once
that the epidermis
serves as a mechan-
ical protection to
the parts beneath
and prevents exces-
sive evaporation,
that the palisade-
cells (which may
not be made out
very clearly in a
roughly prepared
section) hold large
quantities of the
green coloring mat-
ter of the leaf in a
position where it
can receive enough
but not too much
sunlight, and that
the cells of the
Fig. 94. A Stoma of Thyme. (Greatly
magnified.)
A, section at right angles to surface of leaf; B,
surface view of stoma, cu, cuticle; g, guard-
cells; s, stoma; e, epidermal cells; a, air
chamber; c, cells of spongy parenchyma with
grains of chlorophyll.
spongy parenchyma share the work of the palisade-cells,
besides evaporating much water. The stomata admit air
to the interior of the leaf (where the air spaces serve to
store and to distribute it), they allow oxygen and carbonic130
ESSENTIALS OF BOTANY
acid gas to escape, and by closing completely they may
greatly check the loss of water from the plant.
153.	Chlorophyll as found in the Leaf. — Slice off a little
of the epidermis from some such soft, pulpy leaf as that
of the common field sorrel,1 live-for-ever, or spinach ; scrape
from the exposed portion a very little of the green pulp;
examine with the highest power attainable with your
microscope, and sketch several cells. Also study the
chlorophyll in a small moss leaf, e.g., of JInium.
Notice that the green coloring matter is not uniformly
distributed, but that it is collected into little particles
called chlorophyll bodies (Figs. 93, 94).
154.	Woody Tissue in Leaves. — The veins of leaves con-
sist of fibro-vascular bundles containing wood and vessels
much like those of the stem of the plant. Indeed, these
bundles in the leaf are continuous with those of the stem,
and consist merely of portions of the latter, looking as
if unraveled, which pass outward and upward from the
stem into the leaf under the name of leaf-truces. These
traverse the petiole often in a somewhat irregular fashion.
It is now easy to see that the dots noted on the leaf-scars
of the horse-chestnut, the Ailanthus (Fig. 49), and other
trees, are merely the spots at which the leaf-traces passed
from stem to petiole.
155.	Experimental Study of Functions of Leaves.—
The most interesting and profitable way in which to find
out what work leaves do for the plant is by experimenting
upon them. Much that relates to the uses of leaves is
not readily shown in ordinary class-room experiments, but
some things can readily be demonstrated in the experi-
ments which follow.
1 Rumex Acetosella.FUNCTIONS OF LEAVES
131
EXPERIMENT XIV
Transpiration. — Take two twigs or leafy shoots of any thin-leaved
plant;1 cover the cut end of each stem with a bit of grafting wax2
to prevent evaporation from the cut surface. Put one shoot into a
fruit jar and leave in a warm room, screw the top on, put the other
beside it, and allow both to remain some hours. Examine the rela-
tive appearance of the. two, as regards -wilting, at the end of the time.
Which shoot has lost most ? Why? Has the one in the fruit jar
lost any water? To answer this question put the jar (without open-
ing- it) into a refrigerator, or, if the weather is cold, out of doors for
a few minutes, and examine the appearance of the inside of the jar.
What does this show?3
156. Uses of the Epidermis.4 — The epidermis, by its
toughness, tends to prevent mechanical injuries to the
leaf, while by the transformation of a portion of its outer
layers into a corky substance it greatly diminishes the
loss of water from the general surface. In most cases, as
in the india-rubber tree, the epidermal cells (and often two
or three layers of cells beneath these) are filled with water,
and thus serve as reservoirs from which the outer parts of
the leaf and the stem are at times supplied.
In many cases, noticeably in the cabbage, the epidermis
is covered with a waxy coating which doubtless increases
the power of the leaf to retain needed moisture, and which
certainly prevents rain or dew from covering the leaf-
surfaces, especially the lower surfaces, so as to prevent
the operation of the stomata. Many common plants, like
1	Hydrangea, squash, melon, or cucumber is best; many other kinds will
answer very well.
2	Grafting wax may be bought of nurserymen or seedsmen.
8 If the student is in doubt whether the jar filled with ordinary air might
not behave in the same way, the question may be readily answered by putting
a sealed jar of air into the refrigerator.
4 See Kerner and Oliver’s Natural History of Plants, Yol. I, pp. 273-362.182
ESSENTIALS OF BOTANY
the meadow rue and the nasturtium, possess this power to
shed water to such a degree that the under surface of the
leaf is hardly wet at all when immersed in water ; the air-
bubbles on the leaves then give them a silvery appearance.
157.	Hairs on Leaves. —Many kinds of leaves are more
or less hairy or downy, as those of the mullein, the “ mul-
lein pink,” many cinquefoils, and other common plants.
In some instances this hairiness may be a protection
against snails or other small leaf-eating animals, but in
other cases it seems to be pretty clear that the woolliness
(so often confined to the under surface) is to lessen the
loss of water through the stomata.
158.	Operation of the Stomata. — During the early
morning the Stomata usually continue to open gradually
until they reach their maximum size for the day and
then gradually lessen in size until the minimum width is
reached. In some plants the greatest stomatal opening
occurs at about 8 A.M. and the least at about 5 P.M.
When leaves begin to wilt the stomata soon close tightly.
In many plants, especially those with a very thick leaf-
epidermis, the process of giving off water from the leaves,
transpiration, is almost entirely stopped when the stomata
are wholly closed. The under side of the leaf, free from
palisade-cells and abounding in intercellular spaces, is especi-
ally adapted for the working of the stomata, and accordingly
we find them in much greater numbers on the lower than
on the upper surface. On the other hand, the little flower-
less plants known as liverworts, which lie prostrate on the
ground, have their air-pores on the upper surface, and
here also occur the stomata of the leaves of pond-lilies.
In those leaves which stand with their edges nearly ver-
tical, the stomata are distributed somewhat equally on bothFUNCTIONS OF LEAVES
183
surfaces. Stomata occur on the epidermis of young stems,
being replaced later by the lenticels. Those plants which,
like the cactuses, have no ordinary leaves, transpire through
the stomata scattered over their general surfaces.
EXPERIMENT XV
Amount of Water lost by Transpiration. — Procure a thrifty hydran-
gea1 growing in a small flower-pot. Calculate the area of the leaf-
surface by dividing the surface of a piece of tracing cloth into a series
of squares one-half inch on a side,
holding an average leaf against this,
and counting the number of squares
and parts of squares covered by the
leaf. This area multiplied by the
number of leaves will give approxi-
mately the total evaporating surface.
Transfer the plant to a glass bat-
tery jar of suitable size. Cover the
jar with a piece of sheet lead, slit to
admit the stem of the plant, invert
the jar, and seal the lead to the
glass with a hot mixture of beeswax
and resin. Seal up the slit and the
opening about the stem with graft-
ing wax. A thistle-tube, such as is
used by chemists, is also to be in-
serted, as shown in Fig. 95.2 The
mouth of this should be kept corked
when the tube is not in use for
watering.
Fig. 95. A Hydrangea
for Exp. XV.
iThe common species of the green-
houses, Hydrangea Hortensia.
2 It will be much more convenient to tie the hydrangea if one has been
choseu that has but a single main stem. Instead of the hydrangea the com-
mon cineraria, Senecio cruentus, does very well.134
ESSENTIALS OF BOTANY
Water moderately and weigh on a balance that is sensitive to a
tenth of a gram. Record the weight, allow the plant to stand in a
sunny, warm room for twenty-four hours, and reweigh.
Add just the amount of water which is lost,1 and continue the
experiment in the same manner for several days so as to ascertain, if
possible, the effect upon transpiration of varying amounts of water
in the atmosphere.
Calculate the loss per 100 square inches of leaf-surface throughout
the whole course of the experiment.
Try the effect of supplying very little water, so that the hydrangea
will begin to droop, and see whether this changes the relative amount
of transpiration. Vary the conditions of the experiment for a day
or two as regards temperature, and again for a day or two as regards
light, and note the effect upon the amount of transpiration.2
EXPERIMENT XVI
Rise of Sap in Leaves. — Put the freshly cut ends of the petioles
of several thin leaves of different kinds into small glasses, each con-
taining red ink to the depth of one-quarter inch or more. Allow
them to stand for half an hour, and examine by holding up to the
light and looking through them to see into what parts the red ink has
risen. Allow some of the leaves to remain as much as twelve hours
and examine them again. The red-stained portions of the leaf mark
the lines along which, under natural conditions, sap rises into it.
Cut across (near the petiole or midrib ends) all the principal veins of
some kind of large, thin leaf. Then cut off the petiole and at once
stand the cut end, to which the blade is attached, in red ink. Repeat
with another leaf and stand in water. What do the results teach ?
159. Amount of Transpiration. — In order to prevent
wilting, the rise of sap during the life of the leaf must
1	The addition of known amounts of water may be made most conveniently
by measuring it in a cylindrical graduate.
2	When the experiments on the hydrangea have been finished, it should be
kept moderately watered and left sealed up until it is needed for a later
experiment.FUNCTIONS OF LEAVES
135
have kept pace with the evaporation from its surface. A
little calculation will show that the amount of water thus
daily carried off through the foliage of a large tree or the
grass-blades on a meadow is enormous. A grass-plant has
been found to give off its own weight of water every
twenty-four hours, in hot, dry summer weather. This
would make about tons per acre every twenty-four hours
for ordinary grass-fields, or rather over 2200 pounds of
water from a field 50 X 150 feet (i.e., a city lot).
These large amounts of water are absorbed, carried
through the tissues of the plant, and then given off by the
leaves simply because the plant-food contained in the soil-
water is in a condition so diluted that great quantities of
water must be taken in order to secure enough of the
mineral and other substances which the plant demands
from the soil.
160. Accumulation of Mineral Matter in the Leaf. — Just
as a deposit of salt is found in the bottom of a seaside
pool of salt water which has been dried up by the sun, so
old leaves are found to be loaded with mineral matter
left behind as the sap drawn up from the roots is evapo-
rated through the stomata. A bonfire of leaves makes a
surprisingly large heap of ashes. An abundant constitu-
ent of the ashes of burnt leaves is silica, a substance
chemically the same as sand. This the plant is forced to
absorb along with the potash, compounds of phosphorus,
and other useful substances contained in the soil-water;
but since the silica is of hardly any value to most plants,
it often accumulates in the leaf as so much refuse. Lime
is much more useful to the plant than silica, but a far
larger quantity of it is absorbed than is needed; hence it,
too, accumulates in the leaf.136
ESSENTIALS OF BOTANY
161.	Details of the Work of the Leaf.1 — A leaf has four
important functions to perform :
(1)	Fixation of carbon, or	(3) Excretion of water.
photosynthesis.
(2)	Assimilation.2	(1) Respiration.
162.	Absorption of Carbon Dioxide and Removal of its
Carbon. — Carbon dioxide is a constant ingredient of the
atmosphere, usually occurring in the proportion of about
three parts in every 10,000 of air, or one thirty-third of one
per cent. It is a colorless gas, a compound of two simple
substances or elements, carbon and oxygen, the former
familiar to us in the forms of charcoal and graphite, the
latter occurring as the active constituent of air.
Carbon dioxide is produced in immense quantities by
the decay of vegetable and animal matter, by the respira-
tion of animals, and by all fires in which wood, coal, gas,
or petroleum is burned.
Green leaves and the green parts of plants, when they
contain a suitable amount of potassium salts, have the
power of removing carbon dioxide from the air (or in
the case of some aquatic plants from water in which it is
dissolved), retaining its carbon, and setting free part or all
of the oxygen. This process is an important part of the
work done by the plant in making over law materials into
food from which it forms its own substance.
1	See Kerner and Oliver’s Natural History of Plants, Vol. I, pp. 371-483.
2	In many works on botany (1) and (2) are both compounded under the
term assimilation.FUNCTIONS OF LEAVES
137
EXPERIMENT XVII
Oxygen-Making in Sunlight. — Place a green aquatic plant in a
glass jar full of water at a temperature of about 70° Fah. in front
of a sunny window.1 On the surfaces of the plants watch for minute
silvery-looking bubbles. These may be partly air but some are
oxygen. Remove to a dark closet for a few minutes and examine by
lamplight to see whether the rise of bubbles still continues.
This gas may be shown to he oxygen by collecting some
of it in a small inverted test-tube filled with water and
thrusting the glowing coal of a match just blown out into
the gas. It is not, however, very easy to do this satisfac-
torily before the class.
Repeat the experiment, using water which has been well boiled
and then quickly cooled. Boiling removes all the dissolved gases
from water, and they are not redissolved in any considerable quantity
for many hours.
Ordinary air containing a known per cent of carbon dioxide,
if passed very slowly over the foliage of a plant covered with a bell-
glass and pdaced in full sunlight, will, if listed chemically, on com-
ing out of the bell-glass, he found to have lost a little of its carbon
dioxide. The pot in which the plant grows must be covered with a
lid, closely sealed on, to prevent air charged with carbon dioxide (as
the air of the soil is apt to be) from rising into the bell-glass.
163. Disposition made of the Absorbed Carbon Dioxide. —
It would lead the student too far into the chemistry of
botany to ask him to follow out in detail the changes by
which carbon dioxide lets go at least part of its ox}rgen
and gives its remaining portions, namely the carbon and
perhaps part of its oxygen, to build up the substance of
1 Elodeci, Myrioplujllum, Chrysosplenium, Potamogeton, Fontinalis, any o£
the green aquatic flowering plants, or even the common eonfervaceous plants,
known as pond-scum or “frog-spit,” will do for this experiment.138
ESSENTIALS OF BOTANY
the plant. Starch is composed of three elements: hydro-
gen (a colorless, inflammable gas, the lightest of known sub-
stances), carbon, and oxygen. Water is composed largely
of hydrogen, and therefore carbon dioxide and water con-
tain all the elements necessary for making starch. The
chemist cannot put these elements together to form starch,
but at suitable temperatures photosynthesis usually ending
in starch-making goes on constantly in the green parts
of plants when exposed to sunlight and supplied with
water and carbon dioxide.1 The seat of the manufacture
is in the chlorophyll bodies, and protoplasm is without
doubt the manufacturer, but the process is not understood
by chemists or botanists. No carbon dioxide can be taken
up and used by plants growing in the dark, nor in an atmos-
phere containing only carbon dioxide, even in the light.
A very good comparison of the leaf to a mill has been
made as follows2:
The mill :	Palisade-cells and underlying
164. Plants Destitute of Chlorophyll not Starch-Makers.
— Aside from the fact that newly formed starch grains
are first found in the chlorophyll bodies of the leaf and
1	Very likely the plant makes sugar first of all and then rapidly changes
this into starch. However that may he, the first kind of food made in the
leaf and retained long enough to he found there by ordinary tests is starch.
See Pfeffer’s Physiology of Plants, translated by Ewart, Vol. I, pp. 317, 318.
2	By Professor George L. Goodale.
Raw material used:
Milling apparatus:
Energy by which the mill
cells of the leaf.
Carbon dioxide, water.
Chlorophyll grains.
is run:
Manufactured product:
Waste product:
Sunlight.
Starch.
Oxygen.Plate VII. American Mistletoe, Parasitic on a Cottonwood.FUNCTION'S OF LEAVES
139
the green layer of the bark, one of the best evidences of
the intimate relation of chlorophyll to starch-making is
derived from the fact that plants which contain no chloro-
phyll cannot make starch from water and carbon dioxide.
Parasites, like the dodder, which are nearly destitute of
green coloring matter, cannot do this; neither can sapro-
phytes or plants which live on decaying or fermenting
organic matter, animal or vegetable. Most saprophytes,
like the molds, toadstools, and yeast, are flowerless plants
of low organization, but there are a few, such as the curi-
ous pine-sap (frontispiece) which flourishes on rotten wood
or among decaying leaves, that bear flowers and seeds.
165. Detection of Starch in Leaves. — Starch may be
found in abundance by microscopical examination of the
green parts of growing leaves, or its presence may be
shown by testing the whole leaf with iodine solution.
EXPERIMENT XVIII
Occurrence of Starch in Nasturtium Leaves. — Toward the close of
a very sunny day collect some bean leaves or leaves of nasturtium
(Tropceolum). Boil these in water for a few minutes to kill the
protoplasmic contents of the cells and to soften and swell the starch
grains.
Soak the leaves, after boiling, in strong alcohol for a day or two
to dissolve out the chlorophyll, which would otherwise make it diffi-
cult to see the blue color of the starch test, if any -were obtained.
Rinse out the alcohol with plenty of water and then place the leaves
for ten or fifteen minutes in a solution of iodine, rinse off with water,
and note what portions of the leaf, if any, show the presence of starch.
If convenient try the test with a leaf treated as shown in Fig. 96.
What might this prove about importance of sunlight ?
If starch disappeared from between the corks, where did it go?
Review Sects. 17-21, 95-97. Read Sect. 166.140
ESSENTIALS OF BOTANY
166.	Assimilation. — Assimilation means the transforma-
tion of food into the tissues of the plant. From the starch
in the leaf, grape-sugar or malt-sugar is readily formed, and
some of this in turn is apparently combined on the spot with
nitrogen, sulphur, and phosphorus. These elements are de-
rived from salts taken up by the roots and transported to the
leaves. The details of the process are not understood, but
the result of the combination of the sugars or similar sub-
stances with suitable (verj^ minute)
proportions of nitrogen, sulphur,
and phosphorus is to form com-
plex nitrogen compounds. These
are not precisely of the same com-
position as the living protoplasm
of plant-cells or as the reserve
proteids stored in seeds (Sect. 24),
stems (Sect. 91), and other parts
of plants, but are readily changed
into protoplasm or proteid foods
as necessity may demand.
Assimilation is by no means
confined to leaves; indeed, most
of it, as above suggested, must take place in other parts
of the plant.
167.	Excretion of Water and Respiration. — Enough has
been said in Sect. 159 concerning the former of these
processes. Respiration, or consuming oxygen and giving
off carbon dioxide, is an operation which goes on con-
stantly in plants, as it does in animals, and is necessary to
their life. For, like animals, plants get the energy with
which they do the work of assimilation, growth, reproduc-
tion, and performing their movements from the oxidation
Fig. 0G. Leaf of Tropseolum
partly covered with Disks
of Cork and exposed to
Sunlight.
Photograph furnished by the Field Museum of Natural History.
Plate VIII. A Cypress Swamp.FUNCTION'S OF LEAVES
141
of such combustible substances as oil, starch, and sugar.1
In ordinary leafy plants the leaves (through their stomata)
are the principal organs for absorption of air, but much air
passes into the plant through the lenticels of the bark.
168. The Fall of the Leaf. — In the tropics trees retain
most of their leaves the year round; a leaf occasionally
falls, but no considerable portion of them drops at any
one season.2 The same statement holds true in regard to
our cone-bearing evergreen trees, such as pines, spruces,
and the like. But the impossibility of absorbing soil-water
when the ground is at or near the freezing temperature
would cause the death, by drying up, of trees with broad
leaf-surfaces in a northern winter. And in countries where
there is much snowfall most broad-leafed trees could not
escape injury to their branches from overloading with snow,
except by encountering winter storms in as close-reefed
a condition as possible. For such reasons our common
shrubs and forest trees (except the cone-bearing, narrow-
leafed ones already mentioned) are mostly deciduous, that
is, they shed their leaves at the approach of winter.
The fall of the leaf is preceded by important changes
in the contents of its cells.
Much of the starchy, sugary, and protoplasmic contents
of the leaf disappears before it falls. These valuable
materials have been absorbed by the branches and roots,
to be used again the following spring.
The separation of the leaf from the twig is accomplished
bv the formation of a layer of cork cells across the base of
1 The necessity of an air supply about the roots of the plant may be shown
by filling the pot or jar in which the hydrangea was grown for the transpira-
tion experiment perfectly full of water and noting the subsequent appearance
of the plant at periods from twelve to twenty-four hours apart.
- Except where there is a severe dry season.142
ESSENTIALS OF BOTANY
the petiole in such a way that the latter finally breaks off
across the surface of the layer. A waterproof scar is thus
already formed before the removal of the leaf, and there
is no waste of sap dripping from the wound where the
leaf-stalk has been removed, and no chance for molds to
attack the bark or wood and cause it to decay.
169.	Tabular Review of Experiments. — [Continue the table from
Sect. 102.]
170.	Review Summary of Minute Structure of Leaves.1
Layers of tissue seen on a cross- f
section .	.	.	.	.	[
Structure of epidermis.
Structure of stomata.
Distribution of stomata.
Structure and distribution of chlorophyll bodies.
171. Review Summary of Functions of Leaves.
Principal uses of
' palisade-cells,
spongy parenchyma,
waxy coating,
hairs.
fibro-vascular bundles,
epidermis,
stomata,
air spaces.
Substances received by the leaf
Substances manufactured by the leaf.
Substances given off by the leaf .
Mineral substances accumulated in the leaf.
Statistics in regard to transpiration.
1 Illustrate with sketches and diagrams.CHAPTER XIV
THE STUDY OF TYPICAL FLOWERS
172. The Flower of the Trillium. — Cut off the flower-stalk rather
close to the flower; stand the latter, face down, on the table and
draw the parts then shown. Label the green leaf-like parts sepals,
and the white parts, which alternate with these, petals. Turn the
flower face up, and make another sketch, labeling the parts as before,
together with the yellow enlarged extremities or anthers of the stalked
organs called stamens.
Note and describe the way in which the petals alternate with the
sepals. Observe the arrangement of the edges of the petals toward
the base, — how many with both edges outside the others, how many
with both edges inside, how many with one edge in and one out.
Note the veining of both sepals and petals, — more distinct in
which set?1
Pull off a sepal and make a sketch of it, natural size ; then remove
a petal, flatten it out, and sketch it, natural size.
Observe that the flower-stalk is enlarged slightly at the upper end
into a rounded portion, the receptacle, on which all the parts of the
flower rest.
Note how the six stamens arise from the receptacle and their rela-
tions to the origins of the petals. Remove the remaining petals (cut-
ting them off near the bottom with a knife), and sketch the stamens,
together with the other object, the pistil, which stands in the center.
1 In flowers with delicate white petals the distribution of the fibro-vascular
bundles in these can usually be readily shown by standing the freshly cut end
of the peduncle in red ink for a short time, until colored veins begin to appear
in the petals. The experiment succeeds readily with apple, cherry, or plum
blossoms; with white gilliflower the coloration is very prompt. Lily-of-the-
valley is perhaps as interesting a flower as any on which to try the experiment,
since the well-defined stained stripes are separated by portions quite free from
stain, and the pistils are also colored.
143144
ESSENTIALS OF BOTANY
Cut off one stamen, and sketch it as seen through the magnifying
glass. Notice that it consists of a greenish stalk, the filament, and
a broader portion, the anther (Fig. 108). The latter is easily seen
to contain a prolongation of the green filament, nearly surrounded
by a yellow substance. Tn the bud it will be found that the anther
consists of two long pouches or antlier-cells, which are attached by
their whole length to the filament and face inward (towards the
center of the flower). 'When the flower is fairly open the anther-
cells have already split down their margins and are discharging a
yellow, somewhat sticky powder, the pollen.
Examine one of the anthers with the microscope, using the two-
inch objective, and sketch it.
Cut away all the stamens and sketch the pistil. It consists of a
stout lower portion, the ovary, which is six-ridged or angled, and
which bears at its summit three slender stigmas.
In another flower, which has begun to wither (and in which the
ovary is larger than in a newly opened flower), cut the ovary across
about the middle, and try to make out with the magnifying glass
the number of chambers or cells which it contains. Examine the
cross-section with the two-inch objective, sketch it, and note partic-
ularly the appearance and mode of attachment of the undeveloped
seeds or ovules with which it is filled. Make a vertical section of
another rather mature ovary, and examine this in the same way.
Using a fresh flower, construct a diagram to show the relation of the
parts on an imaginary cross-section, as ilhistrated in Fig. 116.1 Con-
struct a diagram of a longitudinal section of the flower, on the general
plan of those in Fig. 114, but showing the contents of the ovary.
Make a tabular list of the parts of the flower, beginning with
the sepals, giving the order of parts and number in each set.
173. The Flower of the Tulip.2 — Make a diagram of a side view
of the well-opened flower as it appears when standing in sunlight.
1	It is important to notice that such a diagram is not a picture of the section
actually produced by cutting through the flower crosswise at any one level,
but that it is rather a projection of the sections through the most typical part,
of each of the floral organs.
2	Tulipa Gesncriana. As the flowers are rather expensive and their parts
are large and firm, it is not absolutely necessary to give a flower to each pupil,
hut some may be kept entire for sketching and others dissected by the class.
All the flowers must be single.THE STUDY OF TYPICAL FLOWERS
145
Observe that there is a set of outer florver-leaves and a set of inner
ones.1 Label the outer set sepals and the inner set petals. In most
flowers the parts of the outer set are greenish, and those of the inner
set of some other color. It is often convenient to use the name
perianth, meaning around the flower, for the two sets taken together.
Note the white waxy bloom on the outer surface of the outer seg-
ments of the perianth. What is the use of this? Note the manner
in which the inner segments of the perianth arise from the top of the
peduncle and their relation to the points of attachment of the outer
segments. In a flower not too widely opened, note the relative posi-
tion of the inner segments of the perianth, — how many wholly out-
side the other two, how many wholly inside, how many with one edge
in and one edge out.
Remove one of the sepals by cutting it off close to its attachment
to the peduncle, and examine the veining by holding it up in a strong
light and looking through it. Make a sketch to show the general
outline and the shape of the tip.
Examine a petal in the same way and sketch it.
Cut off the remaining portions of the perianth, leaving about a
quarter of an inch at the base of each segment. Sketch the up-
right, triangular, pillar-like object in the center and label it pistil;
sketch the organs which spring from around its base and label these
stamens.
Note the fact that each stamen arises from a point just above and
within the base of a segment of the perianth. Each stamen consists
of a somewhat conical or awl-shaped portion below, the filament, sur-
mounted by an ovate linear portion, the anther. Sketch one of the
stamens about twice natural size and label it x 2. Is the attach-
ment of the anther to the filament such as to admit of any nodding
or twisting movement of the former? In a young flower, note the
two tubular pouches or anther-cells of which the anther is composed,
and the slits by which these open. Observe the dark-colored pollen
which escapes from the anther-cells and adheres to paper or to the
fingers. Examine a newly opened anther with the microscope, using
the two-inch objective, and sketch it.
Cut away all the stamens and note the two portions of the pistil,
a triangular prism, the ovary, three roughened scroll-like objects at
1 Best seen in a flower which is just opening.146
ESSENTIALS OF BOTANY
the top, and three lobes of the stigma. Make a sketch of these parts
about twice natural size, and label them x 2. Touch a small camel’s-
hair pencil to one of the anthers, and then transfer the pollen thus
removed to the stigma. This operation is merely an imitation of
the work done by insects which visit the flowers out of doors. Does
the pollen cling readily to the rough stigmatic surface ? Examine this
adhering pollen with the two-inch objective, and sketch a few grains
of it, together with the bit of the stigma to which it clings. Com-
pare this drawing with Fig. 121. Make a cross-section of the ovary
about midway of its length, and sketch the section as seen through
the magnifying glass. Label the three chambers shown cells of the
ovarg1 2 or locules, and the white egg-shaped objects within ovules.11
Make a longitudinal section of another ovary, taking pains to
secure a good view of the ovules, and sketch as seen through the
magnifying glass.
Making use of the information already gained and the cross-
section of the ovary as sketched, construct a diagram of a cross-
section of the entire flower on the same general plan as those shown
in Fig. 116.3
Split a flower lengthwise4 and construct a longitudinal section of
the entire flower on the plan of those shown in Fig. 114, but showing
the contents of the ovary.
174. The Flower of the Buttercup. — Make a diagram of the
mature flower as seen in a side view, looking a little down into it.
Label the pale greenish-yellow', hairy, outermost parts sepals, and
the larger bright yellow parts above and within these petals, and
the yellow-knobbed parts which occupy a good deal of the interior
of the flow'er stamens.
Note the difference in the position of the sepals of a newly opened
flower and that of the sepals of a flower which has opened as wddely
as possible. Note the way in which the petals are arranged in relation
1	Notice that the word cell here means a comparatively large cavity, and is
not used in the same sense in which we speak of a wood-cell or a pith-cell.
2	The section will be more satisfactory if made from an older flower, grown
out of doors, from which the perianth has fallen. In this case label the con-
tained objects seeds.
3	Consult also the footnote to Sect. 172.
4	One will do for an entire division of the class.THE STUDY OF TYPICAL FLOWERS
147
to the sepals. In an opening flower observe the arrangement of the
edges of the petals, — how many entirely outside the others, how
many entirely inside, how many with one edge in and the other out.
Cut off a sepal and a petal, each close to its attachment to the
flower; place both, face down, on a sheet of paper, and sketch about
twice the natural size and label it x 2. Describe the difference in
appearance between the outer and the inner surface of the sepal and
of the petal. Note the little scale at the base of the petal, inside.
Strip off all the parts from a flower which has lost its petals,
until nothing is left but a slender conical object a little more than
an eighth of an inch in length. This is the receptacle or summit of
the peduncle.
In a fully opened flower note the numerous yellow-tipped stamens,
each consisting of a short stalk, the filament, and an enlarged yellow
knob at the end, the anther. Note the division of the anther into
two portions, which appear from the outside as parallel ridges, but
which are really closed tubes, the anther-cells.
Observe in the interior of the flower the somewhat globular mass
(in a young flower almost covered by the stamens). This is a group
of pistils. Study one of these groups in a flower from which the
stamens have mostly fallen off, and make an enlarged sketch of the
head of pistils. Remove some of the pistils from a mature head,
and sketch a single one as seen with the magnifying glass. Label
the little knob or beak at the upper end of the pistil stigma, and the
main body of the pistil the ovary. Make a section of one of the
pistils, parallel to the flattened surfaces, like that shown in Fig. 136,
and note the partially matured seed within.1
1 After Chapter XV has been completed the teacher may find it advisable
to dictate additional studies of some bilaterally symmetrical flowers.CHAPTER XV
THE FLOWER OF THE HIGHER SEED-PLANTS
175. Organs of the Flower.
— The parts usually found
in a flower of the higher
seed-plants are sepals, petals,
stamens, and pistils (Fig. 97).
The sepals, taken together,
constitute the calyx; the
petals, taken together, con-
stitute the corolla. The calyx
and corolla are collectively
known as the floral envelopes
or perianth.
Many flowers mnsist of
five whorls or circles, tivo of which belong to the perianth,
Fig. 97. The Parts of the Flower.
cal, calyx ; cor, corolla; st, stamens;
p, pistil.
Fig. 98. Flower of Stonecrop.
I, entire flower (magnified). II, vertical section (magnified).
two to the stamens, and one to the pistils. The parts of each
whorl alternate in position with those of the preceding or
148THE FLOWER OF THE HIGHER SEED-PLANTS 149
following one, and all the members of each whorl are alike
(Fig. 98).
176.	Suppression and Multiplication of Whorls. — Any
whorl or part of a whorl may be suppressed. If one set of
parts of the perianth is lacking, this is
assumed to be the corolla and the
flower is said to be apetalous (Fig. 99).
Multiplication of whorls is particu-
larly frequent among the stamens, but
other whorls may also show it (see
Figs. 117, 118).
177.	Unisexual Flowers------The sta-
mens and pistils may be produced in 9:'' -Apetalous
separate flowers, which are ’unisexual wild Ginger.
(often called imperfect) flowers. In the
very simple unisexual flowers of the willow (Fig. 100) each
flower of the catkin (Appendix I, Fig. 6) consists merely
of a pistil or a group of (usually two) stamens springing
from the axil of a small bract.
Staminate and pistillate
flowers may be borne on dif-
ferent plants, as they are in
the willow, or they may be
borne on the same plant, as
in the castor-oil plant, Indian
com, and the begonias. When
staminate and pistillate flow-
ers are borne on separate
plants, such a plant is said
to be dioecious (of two house-
holds); when both kinds of
flower appear on the same individual, the plant is said to
be monoecious (of one household).
Fig. 100. Flowers of Willow.
(Magnified.)
A, staminate flower; B, pistillate
flower.150
ESSENTIALS OF BOTANY
Study of Unisexual Flowers.—Examine, draw, and describe the
unisexual flowers of some of the following dioecious plants and one of
the monoecious plants:
r early meadow rue.
Dioecious plants.....................•< willow.
L poplar.
r walnut, oak, chestnut.
Monoecious plants....................<. hickory, alder, beech.
b birch, hazel, begonia.
178. Symmetry of the Flower. — Most angiosperms have
symmetrical flowers. The simplest are those whose parts
are arranged as in Figs. 97, 118, having radial symmetry.
A higher type of flower is that which shows bilateral sym-
metry, as in Figs. 101, 128. If the drawing of such a
flower were folded along the central line, one half of the
drawing would cover and correspond with the other half.
Some flowers are wholly irregular, showing no sort of
symmetry.
179. The Receptacle. — The parts of the flower are borne
on an expansion of the flower-stalk known as the receptacle.THE FLOWER OF THE HIGHER SEED-PLANTS 151
Usually, as in Fig. 98, this is only a slight enlargement of
the flower-stalk, but in the rose (Fig. 102), the pond lily
(Fig. 115), the magnolia, the Calycanthus, and a good many
other familiar flowers it is large and con-
spicuous.
180. The Perianth. — The sepals, or divi-
sions of the calyx, are commonly green and
somewhat leaf-like. The petals in showy
flowers are of many colors, ranging all the
way from violet to red. Either whorl of the
perianth may be found to hdve assumed
some very peculiar form, to carry out the
purpose of the flower, as is briefly explained fig. 102.
in Chapter XVII.	A Rose, Longi-
Among the lower families of seed-plants tudinal Sec-
with closed ovaries the parts of the perianth tIon'
are frequently all distinct, as shown in Fig. 98. Among the
higher families the members of the perianth are often borne
upon a tubular or cuplike outgrowth from the receptacle,
so that the sepals or petals or both appear to have grown
together more or less completely.1
When the calyx or the corolla is borne upon a tubular,
bowl-shaped, or other extension of the receptacle, there are
often divisions, teeth, or lobes at the rim of the tube show-
ing how many sepals or petals the flower possesses.
Special names are given to a large number of forms of the
1 When the parts of the perianth are distinct, the calyx is said to be chorisep-
alous and the corolla choripetalous; other terms are polysepalous and poly-
petalous. When the receptacle forms a cuplike or tubular outgrowth, so that
the teeth or lobes of this alone are sepals or petals, the flower is said to be syn-
sepalous or sympetalous; other terms are gamosepalous or gamopetalous.
Choris means apart, poly means many, syn means together, gamos means
marriage. Botanists have until recently used such expressions as “sepals
united into a tube,” etc., but these are incorrect.152
ESSENTIALS OF BOTANY
sympetalous corolla and these are of much use in accurate
descriptions of seed-plants. A few of these are illustrated
~Y~
Bell-Shaped Corolla of
Bell-Flower (Cam-
panula).
Fig. 104.
Salver-Shaped Corolla of
Jasmine. (Magnified.)
Fig. 105.
Wheel-Shaped
Corolla of
Potato.
in this chapter
(Figs. 103-107).
181. Forms of
the Stamen; Union
of Stamens. — Sta-
mens are of many
their functions in
specialized forms to adapt them
flowers of various shapes,
but many are of the shape
shown in Fig. 108. Such
a stamen consists of an
expanded part, the anther,
borne on a stalk called
the filament. Anthers are
often nearly or quite ses-
sile (i.e. destitute of fila-
ments). Inside the anther
is the powdery or pasty
substance called pollen
(Sect. 190).
Stamens may be wholly unconnected with each other, or
distinct, as shown in Figs. 97, 98, 100, or they may be
Fig. 100.
Fig. 107.
Tubular Corolla, from Labiate or Ringent
Head of Bachelor’s Corolla of Dead
Button.	Nettle.THE FLOWER OF THE HIGHER SEED-PLANTS 153
really or apparently more or less united to each other. In
Fig. 109 the stamens have arisen separately, but finally
become joined together by their anthers
(as is always the case in the family
Composite). In other cases the stamens
appear united when they are not really
so because they are borne on a ring or
tube of tissue, as already explained in
connection with the perianth (Sect. 180).
Without regard to whether the union
is real or apparent, stamens which occur
in a single group
(the filaments appear-
ing joined) are said
to be vionadelphous
(Fig. 110), in two
groups diadelphous
(Fig. Ill), in many groups polyadelphous
(the terms meaning one brotherhood,
two brotherhoods, many brotherhoods).
182. The Carpel. — The simplest form
of the organ which bears the structures
called ovules that are to mature into
seeds is known as the carpel.
In the lowest of the two great groups
of seed-plants, the gymnosperms (mean-
ing naked seeds), to which the pines,
spruces, cedars, and the like belong, the
/, filaments, bearded ovuies are borne exposed on the surface
on the sides.	.
of the carpel, which usually has the form
of a scale. But in the higher group of seed-plants, the
angiosperms (meaning seeds in a vessel) the carpels develop
Fig. 108. Parts of
a Stamen.
A, front; B, back, a,
anther; c,connect-
ive ; /, filament.
Fig. 109. Stamens of
a Thistle, with An-
thers united into a
Ring.
a, united anthers;154
ESSENTIALS OF BOTANY
Fig. 110. Monadel-
phous Stamens of Fig. 111. Diadelphous
Mallow.	Stamens of Sweet Pea.
cases or chambers, in which the ovules are forrilecl, and
which are generally quite closed.
183. The Pistil. — The term pistil (Latin for pestle) is
applied to the closed structure which contains the ovules
and is formed by the carpels of the
angiosperms. This is a more general
term than carpel, for it applies to organs
composed of one or of several carpels.
If one-carpeled, a pistil is said to be
simple; if of two or
more carpels, it is
compound.
The pistil often
consists of the parts
shown in Fig. 112,
an enlarged hollow portion containing ovules and known
as the ovary, a stalk-like style, and a knob
or ridged expansion called the stigma.
Not infrequently the style is wanting and
the stigma is sessile (seated) on the ovary.
A flower may contain a large number
of carpels in the form of simple pistils
entirely separate from one another, as in
the buttercup and the stonecrop (Fig. 98).
When several carpels form a compound
pistil, the manner and extent of the union
is various. The union generally forms the
ovary, although this is sometimes developed ov' °''ary 1 s.ty'style:
in large part as a cuplike or tubular growth
under the carpels. Sometimes the union is complete, so that
the compound pistil has only one style and stigma. But
frequently the styles remain separate, or the styles may be
stiff—O
Fig. 112. Parts
of the Pistil.THE FLOWER OF THE HIGHER SEED-PLANTS 155
united and the stigmas separate or at least lobed, so as to
show of how many carpels the pistil is made up (Figs. 99,
100). Even when there is no external sign to indicate the
compound-nature of the pistil, it can usually be recognized
from a study of a cross-section of the ovary.
184.	Locules of the Ovary; Placentas. — Compound
ovaries very commonly consist of a number of separate
chambers known as locules.
Fig. 113, JD, shows a three-
loculed ovary seen in cross-
section. The ovules are
not borne indiscriminately
by any part of the lining of Fig. 113. Principal Types of Placenta,
the ovary. In one-loculed parietal placenta; B, central placenta?
pistils they frequently grow t'> freecentral placenta; A and B.trans-
..	.	verse sections; C\ longitudinal section.
in a line running along one
side of the ovary, as in the pea pod (Fig. 146). The ovule-
bearing line is called a placenta; in compound pistils there
are commonly as many placentas as there are separate
carpels joined to make the pistil. Placentas on the wall
of the ovary, like those in Fig. 113, .1, are called parietal
placentas; those which occur as at Z>, in the same figure,
are said to be central; and those which, like the form rep-
resented in C of the same figure, consist of a column
rising from the bottom of the ovary are called free central
placentas.
185.	Superior, Half-Inferior, and Inferior Ovaries______
When, as in the flower of Fig. 98, the receptacle is rounded
or club-shaped and the floral organs arise from it in suc-
cessive sets, the flower is said to be hypogynous, from two
Greek words, here applied to mean under the pistil, and the
ovaries are said to be superior (Fig. 114, I).156
ESSENTIALS OF BOTANY
II	III
Eig. 114. Insertion of the
Floral Organs.
When the receptacle is concave, so that the pistil is
inserted on the same level with the stamens or lower, but
not at all united with the
receptacle, the flower is said
to be perigynous (around the
pistil) and the ovary is half-
inferior (Fig. 114, II). When
the ovary is united with the
receptacle, the flower is said to
be epigynous (upon the pistil) or
the ovary is inferior (Fig. 99).
I, hypogynous, all the other parts on	,fiG pi,,..! T)jamnK
the receptacle, beneath the pistil;	iab • * 10raI diagrams,
ii, perigynous, petals and stamens Sections (real or imaginary)
apparently growing out of the ,,	. ., a	,	,,
calyx, around the pistil; in, eo- through the flower lengthwise,
rolla hypogynous, stamens like those of Fig. 114, help
epipetalous.	,,	.	. .
greatly in giving an accurate
idea of the relative position of the floral organs. Still
more important in this way
are cross-sections, which may
be recorded in diagrams like
those of Fig. 116.1
In constructing such dia-
grams it will often be neces-
sary to suppose some of the
parts of the flower to be raised
or lowered from their true
position, so as to bring them
into such relations that all
could be cut by a single sec-
tion. This would, for instance, be necessary in making
Fig. 115. White Water-Lily.
The inner petals and the stamens
growing from the ovary.
1 For floral diagrams see L<* Maout and Decaisne’s TraiU General de
Botanique or Eichler’s Bliithendiagramme.THE FLOWER OF THE HIGHER SEED-PLANTS 157
a diagram for the cross-section of the flower of the white
water-lily, of which a partial view of one side is shown in
Fig. 115.
Construct diagrams of the longitudinal section and the transverse
section of several large flowers, following the method indicated in
Figs. 114 and 116, but making the longitudinal section show the
interior of the ovary.1
It is found convenient in dia-
grams of cross-sections to distin-
guish the sepals from the petals
I	II	ill
Fig. 116. Diagram of Cross-Sections of Flowers.
I, columbine; II, Heath family; III, Iris family. In each diagram the dot
alongside the main portion indicates a cross-section of the stem of the
plant. In II every other stamen is more lightly shaded, because some
plants of the Heath family have five and some ten stamens.
by representing the former with midribs. The diagram-
matic symbol for a stamen stands for a cross-section of the
anther, and that for the pistil is a section of the ovary.
If any part is lacking in the flower (as in the case of
flowers which have some antherless filaments), the missing
or abortive organ may be indicated by a dot. In the
1 Among the many excellent early flowers for this purpose may he men-
tioned trillium, bloodroot, dogtooth violet, marsh marigold, buttercup, tulip
tree, horse-chestnut, Jeffersonia, May-apple, cherry, apple, tulip, daffodil,
primrose, wild ginger, cranesbill, locust, bluebell.158
ESSENTIALS OF BOTANY
diagram of the Iris family (Fig. 116, III) the three dots
inside the flower indicate the position of a second circle
of stamens, found in most flowers of monocotyledons, but
not found in this family.
187. Review Summary of Chapter XV.
The organs of the flower and their arrangement.1
Kinds of flower as regards symmetry .
The receptacle.
r appearance of circles.
The perianth . J apparent union of sepals.
I apparent union of petals.
parts .
The stamens
The carpel.
real union,
apparent union.
The pistil .
The ovary .
parts .................... .	.	.
simple pistil.
^ compound pistil.
tjrpes of placenta.................
positions relative to other circles .
{
1.
2.
3.
1.
2.
3.
(t
i.
3
r
i
1 Illustrate by sketches when possible.CHAPTER XVI
TRUE NATURE OF FLORAL ORGANS; DETAILS OF
THEIR STRUCTURE; FERTILIZATION
188. The Flower a Shortened and greatly Modified
Branch. — In Chapter IX the leaf-bud was explained
as being an undeveloped branch, which in its growth
would develop into a real branch (or a prolongation of
the main stem). Xow, since flower-buds appear regularly
either in the axils of leaves or as terminal buds, there is
reason to regard them as of similar nature to leaf-buds.
Fig. 117. Transition from Bracts to Sepals in a Cactus Flower.
Tliis would imply that the receptacle corresponds to the
axis of the bud shown in Fig. 55, and that the parts of
the flower correspond to leaves. There is plenty of evi-
dence that this is really true. Sepals frequently look
159160
ESSENTIALS OF BOTANY
very much like leaves, and in many cactuses the bracts
about the flower are so sepal-like that it is impossible to
tell where the bracts end and the sepals begin (Fig. 117).
The same thing is true of sepals and petals in such flowers
as the white water-lily. In this flower there is a remark-
able series of intermediate steps, ranging all the way from
petals, tipped with a bit of anther, through stamens with
a broad petal-like filament, to regular stamens, as is shown
Fig. 118. Transitions from Petals to Stamens in White Water-Lily.
E, F, G, //, various steps between petal and stamen.
in Fig. 118, E, F, G, IT. The same thing is shown in
many double roses. In completely double flowers the
stamens and pistils are transformed by cultivation into
petals. In the flowers of the cultivated double cherry the
pistils occasionally take the form of small leaves, and some
roses turn wholly into green leaves.
Summing up, then, we know that flowers are altered
and shortened branches: (1) because flower-buds have, as
regards position, the same kind of origin as leaf-buds:
(2) because all the intermediate steps are found between
bracts, on the one hand, and stamens, on the other.ORIGIN OF FLORAL ORGANS
161
189.	Beginnings of the Flower below the Seed-Plants.—
A flower, as has just been stated (Sect. 188), is a shortened
and modified branch. Its use is to reproduce the plant
by the union of male and female cells (produced by the
stamens and pistils respectively), as is explained in Sects.
193, 194. We may properly apply the name flower to
any portion of stem modified to bear clustered organs which
produce cells that unite and mingle their contents to repro-
duce the plant.
Conelike clusters of reproductive organs are found in
the club-mosses (Lycopodium) (Fig. 213), and the horse-tails
or scouring-rushes (Equisetum) (Fig. 211). These simple
flowers of plants which grow from spores (Sect. 265), not
from seeds with embryos, are much more like the cones
of pines and other evergreen trees than like ordinary
flowers; for the flowers of spore-plants and the cones of
the evergreen trees and shrubs are extremely simple in
many ways, and agree also in their spiral arrangement and
in having no flower leaves corresponding to sepals and
petals. Since the general law among plants and animals
is that the more complex forms are descended from sim-
pler ones (Chapter XXVI), it is allowable to suppose that
ordinary flowers are remotely descended from some such
conelike structures as those of Figs. 211, 213.
The development of flowers has generally been toward
making them more showy, thus reducing waste of pollen
(Sect. 195 and Chapter xvn).
190.	The Anther and its Contents. — Some of the shapes
of anthers may be learned from Figs. 108 and 119.1 Most
anthers are thicker than the filament and two-lobed, the
halves being joined by a connective (Fig. 108, c), which is
1 See Kerner and Oliver’s Xatural History of Plants, Vol. II, pp. 86-95.162
ESSENTIALS OF BOTANY
merely a prolongation of the filament. Within each lobe
are two pollen-sacs filled with mother cells from which
the pollen grains are developed, each cell usually pro-
ducing four pollen grains.
After the anther has ma-
tured, the two sacs of each
lobe commonly run together
into one cavity, which is only
partially filled with pollen
grains. The shape of the
anther and the way in which
it opens depend largely upon
the way in which the pollen
is to be discharged and how
it is carried from flower to
flower. The commonest
method is to have the anther-
cells split lengthwise, as in
Fig. 119,1. A few anthers open by trap-doors like valves,
as in II, and a larger number by little holes at the top, as
in III.
Sometimes the anthers face outward and open outward,
as in the wild ginger (Fig. 98); but more frequently they
face and open inward, as in the thistle, the pond lily, and
the primrose (Figs. 109, 115, and 134).
The pollen in many plants with inconspicuous flowers,
as the evergreen cone-bearing trees, the grasses, rushes,
and sedges, is a fine, dry powder. Powdery pollen is
adapted to be carried by the wind. In plants with showy
flowers the pollen is often somewhat sticky or pasty.
Sometimes pollen grains of this kind are bound together
in small masses by fine, cobweb-like threads, as in the
Milkweed Family (Asclepiadacecc).
i	ii	iii
Fig. 119. Modes of discharging
Pollen.
I, by longitudinal slits in the anther-
cells (amaryllis); II, by uplifted
valves (barberry); III, by a pore
at the top of each anther-lobe
(nightshade).STRUCTURE OF FLORAL ORGANS
163
Fig. 120 will serve to furnish examples of some of the
shapes which pollen grains assume; c in the latter figure is
perhaps as common a form as any. Each pollen grain con-
sists mainly of a single cell, and is covered by a moderately
thick outer wall and a thin inner one. Its contents are
thickish protoplasm, full of opaque particles, and usually
containing grains of starch and little drops of oil. The
knobs on the outer coat, as shown in Fig. 120, b, mark
Fig. 120. Pollen Grains. (Very greatly magnified.)
a, pumpkin; b, enchanter’s nightshade; c, Albuca; d, pink; e, hibiscus.
the spots at which the inner coat of the grain is finally
to burst through the outer one, pushing its way out in
the form of a slender, thin-walled tube.1
191. The Formation of Pollen Tubes. — This can be
studied in pollen grains which have lodged on the stigma
and there been subjected to the action of its moist surface.
It is, however, easier to cause the artificial production of
the tubes.
EXPERIMENT XIX
Production of Pollen Tubes. — Place a few drops of suitably diluted
syrup with some fsesh pollen in a concave cell ground in a microscope
slide; cover with a thin glass circle; place under a bell-glass, with a
wet cloth or sponge to prevent evaporation of the syrup, and set
1 See Kemer and Oliver’s Natural History of Plants, Vol. II, pp. 95-104.164
ESSENTIALS OF BOTANY
aside in a warm place, or merely put some pollen in syrup in a watcb
crystal under the bell-glass. Examine from time to time to note the
appearance of the pollen tubes. Try several kinds of pollen if possi-
ble, using syrups of various strengths. The following kinds of pollen
form tubes readily in syrups of the strengths indicated.
Tulip.....................................1 to 3 per cent.
Narcissus .	.	.......................3 to 5	“
Cytisus canariensis (called Genista by florists)	15	“
Chinese primrose .	.	  10	“
Sweet pea1 ...	............ 10 to 15	“
Tropieolum1..................................... 15	“
192. Microscopical Structure of the Stigma and Style. —
Under a moderate power of the microscope the stigma is
seen to consist of cells set irregularly over the surface, and
secreting a moist liquid to which
the pollen grains adhere (Fig. 121).
Beneath these superficial cells and
running down through the style
(if there is one) to the ovary is
spongy parenchyma. In some
pistils the pollen tube proceeds
through the cell-walls, which it
softens by means of a substance
which it exudes for that purpose.
In other cases (Fig. 122) there is
a canal or passage along which
the pollen tube travels on its way
to the ovule.
Fir,. 121. Stigma of Thorn-
Ajiple (Datura) with Pol-
len. (Magnified.)
1 The sweet-pea pollen and that of tropoeolum are easier to manage than
any other kinds of which the author lias personal knowledge. If a concaved
slide is not available, the cover-glass may be propped up on hits of the thinnest
broken cover-glasses. From presence of air or some other reason, the forma-
tion of pollen tubes often proceeds most rapidly j ust inside the margin of the
cover-glass.FERTILIZATION
165
193. Fertilization.— Fertilization in seed-plants means
the union of a sperm nucleus derived from a generative
Fig. 122. Pollen Grains producing
Tubes, on Stigma of a Lily.
(Much magnified.)
g, pollen grains; t, pollen tubes;
p, papillae of stigma; c, canal or
passage running toward ovary.
cell of a pollen grain with an
egg-cell at the apex of the
embryo sac (Fig. 124). This
process gives rise to a cell
Fig. 123. Germination of Pollen
Grain of an Angiosperm. (Much
magnified and somewhat dia-
grammatic.)
A, entire grain, with germination con-
siderably advanced. B, tip of pollen
tube at a much later stage, after the
tube nucleus has disappeared: g, the
generative cell beginning to enter the
tube; t, the tube nucleus; s, sperm
cells formed from the generative cell.
which contains material derived from the pollen and from
the egg-cell. In a great many plants the pollen, in order to
accomplish the most successful fertilization, must come
from another plant of the same kind, not from the indi-
vidual which bears the ovules that are being fertilized.
Pollen tubes begin to form soon after pollen grains lodge
on the stigma. The time required for the tube to penetrate
to the ovary varies in different kinds of plants.
Finally the tube enters the opening at the apex of the166
ESSENTIALS OF BOTANY
ovule to, in Fig. 124, reaches one of the cells shown at e,
and transfers a sperm nucleus into this egg-cell. The
Fio. 124. Diagrammatic Representation
of Fertilization of an Ovule.
i, inner coating of ovule; o, outer coating
of ovule; p, pollen tube, proceeding from
one of the pollen grains on the stigma;
c, the place where the two coats of the
ovule blend (the kind of ovule here
shown is inverted, its opening m being at
the bottom, and the stalk/adhering along
one side of the ovule); a to e, embryo sac,
full of protoplasm; a, so-called antipodal
cells of embryo sac; n, central nucleus of
the embryo sac; e, nucleated cells, one
of which, the egg-cell, receives the essen-
tial contents of the pollen tube; /, funi-
culus or stalk of ovule; m, opening into
the ovule
latter is thus enabled to
divide and finally grow
into an embryo. This
the cell does by forming
cell-walls and then
increasing by continued
subdivision in much the
same way in which the
cells at the growing
point near the tip of the
root subdivide.1
194. Nature of the
Fertilizing Process. —
The necessary feature of
the process of fertiliza-
tion is the union of the
essential contents of tivo
cells to form a new one
from which the future
plant is to spring. This
kind of union is found
to occur in many crypto-
gams (Chapters xxiil-
xxvii), resulting in the
production of a spore
capable of growing into
a complete plant.
1 See Strasburger, Noll,
Schenk and Karsten’s Text-
Book of Botany, pp. 442-446.FERTILIZATION
167
195. Number of Pollen Grains to Each Ovule. — Only
one pollen tube is necessary to fertilize each ovule, but so
many pollen grains are lost that plants produce many
more of them than of ovules. The ratio, however, varies
greatly. In the night-blooming cereus there are about
250,000 pollen grains for 30,000 ovules, or rather more
than 8 to 1, while in the common garden wisteria there
are about 7000 pollen grains to every ovule, and in Indian
corn, the cone-bearing evergreens, and a multitude of other
plants, many times more than 7000 to 1. These differences
depend upon the mode in which the pollen is carried from
the stamens to the pistil.CHAPTER XVII
ECOLOGY OF FLOWERS; POLLINATION
196.	Topics of the Chapter. — The ecology of flowers is
concerned mainly with the means by which the transfer-
ence of pollen or pollination is effected, and with the ways
in which pollen is kept away from undesirable insect
visitors and from rain.
197.	Cross-Pollination and Self-Pollination.—It was long
supposed by botanists that the pollen of any perfect flower
needed only to be placed on the stigma of the same
flower to insure satisfactory fertilization. At present it is
known that probably nearly all attractive flowers, even if
they can produce some seed when self-pollinated, do far
better when pollinated from the flowers of another plant
of the same kind.1 This important fact was established
by a long series of experiments on the number and vitality
of seeds produced by a flower when treated with its own
pollen, or self-pollinated, and when treated with pollen
from another flower of the same kind, or cross-pollinated.2
198.	Wind-Pollinated Flowers.^—It has already been
mentioned that some pollen is dry and powdery and other
kinds are more or less sticky. Pollen of the dusty sort is
light, and therefore adapted to be blown about by the
1	See Darwin’s Cross and Self-Fertilization in the Vegetable Kingdom
(especially Chapters I and II).
2	On dispersion of pollen see Kerner and Oliver, Vol. II, pp. 129-287.
8 See Newell’s Reader in Botany, Part II, Chapter VII.
108ECOLOGY OF FLOWERS; POLLINATION 169
wind. Any one who has been much in cornfields after
the corn has “ tasseled ” has noticed the pale yellow dusty
pollen which flies about when a cornstalk is jostled, and
which collects in considerable quantities on the blades of
the leaves. Corn is monoecious, but fertilization is best
accomplished by pollen blown from the “ tassel ” (stamens)
of one plant to the “silk” (pistils) of another plant. The
pistil of wind-pollinated flowers is often feathery and thus
adapted to catch flying pollen-
grains (Fig. 125). Other charac-
teristics of such flowers are the
inconspicuous character of their
perianth, which is usually green pIG. 125. pistil of a Grass,
or greenish, the absence of odor provided with a Feathery
and of nectar, the regularity of Stigma, adapted for Wind-
the corolla, and the appearance
of the flowers before the leaves or their occurrence on
stalks raised above the leaves.
Pollen is, in the case of a few aquatic plants, carried
from flower to flower by the water on which it floats.
199.	Insect-Pollinated Flowers. — Most plants which
require cross-pollination depend upon insects as pollen-
carriers,1 and it may be stated as a general fact that the
showy colors and markings of flowers and their odors all
serve as so many advertisements of the nectar (commonly
but wrongly called honey) or of the nourishing pollen
which the flower has to offer to insect visitors.
200.	Pollen-Carrying Apparatus of Insects.2 — Ants and
some beetles which visit flowers have smooth bodies to
which little pollen adheres, so that their visits are often of
1 A few are pollinated by snails; many more by humming-birds and other
birds.	2 See Knuth-Davis’ Handbook of Flower Pollination.170
ESSENTIALS OF BOTANY
slight value to the flower ; but many beetles, all butterflies
and moths, and most bees have bodies roughened with
scales or hairs which hold a good deal of pollen entangled.
In the common honey-bee
(and in many other kinds)
the greater part of the insect
is hairy, and there are special
collecting baskets, formed
by bristle-like hairs, on the
hind legs (Fig. 126). It is
easy to see the load of pol-
len accumulated in these
baskets after such a bee lias
visited several flowers. Of
course the pollen which the
bee packs in the baskets and
carries off to the hive, to be
stored for food, is of no use
in pollination.
201.	Nectar and Nectaries. — Nectar is a sweet liquid
which flowers secrete for the purpose of attracting insects.
After partial digestion in the crop of the bee, nectar
becomes honey. Those flowers which secrete nectar do
so by means of nectar glands, small organs whose structure
is something like that of the stigma, situated often near
the base of the flower, as shown in Fig. 127. Sometimes
the nectar clings in droplets to the surface of the nectar
glands; sometimes it is stored in little cavities or pouches
called nectaries. The pouches at the bases of columbine
petals are among the most familiar of nectaries.
202.	Odors of Flowers. — The acuteness of the sense of
smell among insects is a familiar fact. Flies buzz about the
A, right hind leg of a honey-bee (seen
from behind and within); B, the
| tibia, ti, seen from the outside, show-
ing the collecting basket formed of
stiff hairs.ECOLOGY OF FLOWERS; POLLINATION 171
wire netting which covers a piece of fresh meat or a dish of
syrup, and bees, wasps, and hornets will fairly besiege the
window screens of a kitchen where preserving is going on.
Many plants find it possible to attract as many insect visitors
as they need without giving off any scent, but small flowers,
like the mignonette, and night-blooming ones, like the white
tobacco and the evening primrose, are sweet-scented to at-
tract night-flying moths. It is interesting to observe that the
majority of the flowers which bloom at night are white, and
that they are much more generally sweet-scented than flowers
which bloom during the day. A few flowers are carrion-
scented (and purplish or brownish colored) and attract flies.
203. Colors of Flowers. — Flowers which are of any
other color than green probably in most cases display their
colors to attract insects, or occasion-
ally birds.
It is certain, however, that colors
are less important means of attrac-
tion than odors, from the fact that
insects are extremely near-sighted.
Butterflies and moths cannot see
distinctly at a distance of more than
about five feet, bees and wasps at
more than two feet, and flies at more
than two and a fourth feet. Prob-
ably no insects can make out objects
clearly more than six feet away;1
yet it is quite possible that their attention is attracted by
colors at distances greater than those mentioned.2
1	See Packard’s Text-Book of Entomology, p. 260.
2	See Lubbock’s Flowers, Fruits, and Leaves, Chapter I. On the general
subject of colors and odors in relation to insects, see Knuth-Davis’ Handbook
of Flower Pollination, Clarendon Press, Oxford.
Fig. 127. Stamens and
Tistil of the Grape (mag-
nified), with a Nectar
Gland, g, between Each
Pair of Stamens.172
ESSENTIALS OF BOTANY
204. Nectar Guides. — In a large number of cases the
petals of flowers show decided stripes or rows of spots of
a color different from that of most of the petal. These
commonly lead toward the nectaries, and it is possible
that such markings point out to insect visitors the way to
the nectaries. Following this course, the insect not only
secures the nectar which he seeks, but probably leaves
pollen on the stigma and becomes dusted with new pollen,
which he carries to another flower.
205. Facilities for Insect Visits.
— Regular polypetalous flowers
have no special adaptations to make
them singly accessible to insects,
but they lie open to all comers.
Bisexual flowers probably always
are more or less adapted to partic-
ular insect (or other) visitors. The
adaptations are extremely numer-
ous; here only a very few of the
simpler ones will be pointed out.1
Where there is a drooping lower
petal (or, in the case of a gamopetalous corolla, a lower
lip), this serves as a perch upon which flying insects may
alight and stand while they explore the flower, as the
beetle is doing in Fig. 128. In Fig. 129 one bumblebee
stands with her legs partially encircling the lower lip of
the dead-nettle flower, while another perches on the sort
of grating made by the stamens of the horse-chestnut
flower. The honey-bee entering the violet clings to the
beautifully bearded portion of the two lateral petals while
it sucks the nectar from the spur beneath.
1 See Kmith-Davis’ Handbook of Flower Pollination.
Big. 128. A Beetle on the
Flower of the Twayblade.
(Enlarged three times.)Plate IX. Dogwood (Cornus florida), with Showy Involucres to
attract Insects.ECOLOGY OF FLOWERS; POLLINATION 173
206. Protection of Pollen from Unwelcome Visitors—It
is usually desirable for the flower to prevent the entrance
of small creeping insects, such as ants, which carry little
pollen and eat a relatively large amount of it. The means
adopted to secure this result are many and curious. In
some plants, as the common catchfly, there is a sticky
\ \
Fig. 129. Bees visiting Flowers.
At the left, a bumblebee on the flower of the dead nettle; below, a similar
bee in the flower of the horse-chestnut; above, a. honey-bee in the
flower of a violet.
ring about the peduncle, some distance below the flowers,
and this forms an effectual barrier against ants and like
insects. Very frequently the calyx tube is covered with
hairs, which are sometimes sticky.
Sometimes the recurved petals or divisions of the corolla
stand in the way of creeping insects. In other cases the
throat of the corolla is much narrowed or closed by hairs174
ESSENTIALS OF BOTANY
or by appendages.1 Those flowers which have one or
more sepals or petals prolonged into spurs, like the nastur-
tium and the columbine, are inaccessible to most insects
except those which have a tongue or a sucking-tube long
Fig. 130. A Sphinx Moth with a Long Sucking-Tube.
enough to reach to the nectary at the bottom of the spur.
The large sphinx motli, shown in Fig. 180, which is a com-
mon visitor to the flowers of the evening primrose, is an
example of an insect especially adapted to reach deep
into long tubular flowers.
207.	Bird-Pollinated Flowers.—Some flowers with very
long tubular corollas depend entirely upon birds to carry
their pollen for them. Among garden flowers the gladi-
olus, the scarlet salvia, and the trumpet honeysuckle are
largely dependent upon humming-birds for their pollina-
tion. The wild balsam or jewel-weed and the trumpet-
creeper are also favorite flowers of the humming-bird.
208.	Prevention of Self-Fertilization. — Dioecious flowers
are of course quite incapable of self-pollination.
1 On protection of pollen, see Kerner and Oliver, Yol. II, pp. 95-109.ECOLOGY OF FLOWERS; POLLINATION 175
Many flowers which appear to be designed to secure
self-pollination are almost or quite incapable of it. Fre-
quently the pollen from another plant of the same species
prevails over that which the flower may shed on its own
pistil, so that when both kinds are placed on the stigma
together it is the foreign pollen which fertilizes.
209. Dichogamy; Movements of Stamens. — If the sta-
mens mature at a different time from the pistils, self-
pollination is as effectually
prevented as though the
plant were dioecious. This
unequal maturing, or di-
chogamy, occurs in many
kinds of flowers. In some, -1
the figwort and the com-
mon plantain for example,
the pistil develops before
the stamens, but usually
the reverse is the case. The
Clerodendron? a tropical
Africau flower (Fig. 131),
illustrates in a most strik-
ing way the development
of stamens before the pistil.
Besides the slow move-
ments which the stamens
and pistil make in such
cases as that of the Clerodendron, the parts of the flower
often, as in the barberry and Kalmia, admit of extensive
and rather quick movements to assist the insect visitor to
become dusted or smeared with pollen.
1 0. Thompsonix.
Flower of Clerodendron in
Two Stages.
In A (earlier stage) the stamens are ma-
ture, while the pistil is still undevel-
oped and bent to one side. In B (later
stage) the stamens have withered and
the stigmas have separated, ready for
the reception of pollen.176
ESSENTIALS OF BOTANY
Fig. 132. Flowers of Yucca visited by a Moth.ECOLOGY OF FLO AYERS ; POLLINATION 177
210. Pollination in Yucca. —The yuccas and allied genera
are xerophytes (some of them low plants and others tree-
like) which abound especially in the desert and semi-desert
portions of the southwestern United States and in Mexico
(Plate AT). The flowers are white or whitish, borne in
great clusters, and are very conspicuous at night. The
stamens are shorter than the pistil, and the pollen is sticky.
The pistil consists of three carpels which form a tube
stigmatic on its inner surface.
Pollination is impossible without the aid of insects. It is
effected by a small moth (Pronuba) which throughout the
day remains at rest within the flower (Fig. 132).1 At
dusk the female moth begins the work of pollmating the
yucca flowers. She clings to the
stamens and collects a mass of
pollen (Fig. 133). Continuing
her work hi the same flower, the
moth stings one of the ovaries
and deposits an egg in an ovule,
then mounts2 to the tip of the
pistil and crowds some pollen
into the mouth of the stigmatic
tube. Self-pollination is thus
secured. She then descends to
the ovary and deposits another
egg, ascends to the stigma to pollinate it, and so on. Each
grub when hatched from the egg feeds on the ovule in which
the egg was laid; but the ovules are very numerous, so
that many of them are left uneaten and ripen into seeds.
Fig. 133. Head of Yucca
Moth. (Magnified.)
p, mass of pollen held in position
by spinous appendages of the
moth’s head.
1 In the first flower (the lowest) the moth is gathering pollen; in the second
she is pollinating the stigma ; in the third she is in the position of rest duriDg
the day; in the fourth in the position of rest when disturbed ; iu the fifth ovi-
positing.	2 That is, travels away from the receptacle.178
ESSENTIALS OF BOTANY
211. Flowers with Stamens and Pistils Each of Two
Lengths.— Tlie flowers of bluets, partridge-berry, the prim-
roses, and a few other common plants secure cross-pollina-
tion by having essential organs of two forms (Fig. 134).
Such flowers are said to be dimorphous (of two forms). In
the short-styled flowers, II, the anthers are borne at the
top of the corolla tube and
the stigma stands about
halfway up the tube. In
the long-styled flowers, I,
the stigma is at the top
of the tube and the anthers
are borne about halfway up.
An insect pressing its head
into the throat of the corolla
of II would become dusted
with pollen, which would be
brushed off on the stigma
of a flower like I. On leav-
ing a long-styled flower the
bee's tongue would be
dusted over with pollen,
some of which would neces-
sarily be rubbed off on the stigma of the next short-styled
flower that was visited. Cross-pollination is insured since
all the flowers on a plant are of one kind, either long-
styled or short-styled, and since the pollen is of two sorts,
— each kind sterile on the stigma of any flower of similar
form to that from which it came.
Trimorphous flowers, with long, medium, and short
styles, are found in a species of loosestrife.1
1 See Newell’s Reader in Botany, Part II, pp. 60-63.

I	II
Fig. 134. Dimorphous Flowers
of the Primrose.
I, a long-styled flower; II, a short-
styled one.ECOLOGY OF FLOWERS; POLLINATION 179
212.	Studies in Insect Pollination. — The student cannot gather
more than a very imperfect knowledge of the details of cross-polli-
nation in flowers without actually watching some of them as they
grow, and observing their insect visitors. If the latter are caught
and dropped into a wide-mouthed stoppered bottle containing a bit
of cotton saturated with chloroform, they will be piainlessly killed,
and most of them may be identified by any one who is familiar with
our common insects. The insects may be observed and classified
in a general way as butterflies, moths, bees, flies, wasps, and beetles,
without being captured or molested.
Whether these out-of-door studies are made or not, several flowers
should be carefully examined and described as regards their arrange-
ments for attracting and utilizing insect visitors (or birds).
213.	Cleistogamous Flowers--------In marked contrast with
such flowers as those discussed in the preceding sections,
which bid for insect visitors or expose their pollen to be
blown about by the wind, are certain flowers which remain
closed even during the pollination of the stigma. These
flowers are called cleistogamous and of course are not cross-
pollinated. Usually they occur on plants which also bear
flowers adapted for cross-pollination, and in this case the
closed flowers are much less conspicuous than the others,
yet they produce much seed. Every one knows the ordi-
nary flowers of the violet, but most people do not know
that violets very generally, after the blossoming season (of
their showy flowers) is over, produce many cleistogamous
flowers, as shown in Fig. 135.180
ESSENTIALS OF BOTANY
Fig. 135. A Violet with Cleistogamous Flowers.
The objects which look like flower-buds are cleistogamous flowers in
various stages of development. The pods are the fruit of similar
flowers. The plant is represented as it appears in late July or
August, after the ordinary flowers have disappeared.CHAPTER XVIII
THE STUDY OF TYPICAL FRUITS
214.	A Berry, the Tomato.1—Study the external form of the
tomato, and sketch it, showing the persistent calyx and peduncle.
Cut a cross-section at about the middle of the tomato. Xote
the thickness of the epidermis (peel off a strip) and of the wall of
the ovary. Note the number, size, form, and contents of the cells
of the ovary. Observe the thickness and texture of the partitions
between the cells. Sketch.
Xote the attachments of the seeds to the placentas and the gelati-
nous, slippery coating of each seed.
The tomato is a typical berry, but its structure presents fewer
points of interest than are found in some other fruits of the same
general character, so the student will do well to spend a little more
time on the examination of such fruits as the orange or the lemon.
215.	A Hesperidium, the Lemon. — Procure a large lemon which
is not withered, if possible one which still shows the remains of the
calyx at the base of the fruit.
Xote the color, general shape, surface, remains of the calyx, knob
at the portion formerly occupied by the stigma. Sketch the fruit
about natural size. Examine the pitted surface of the rind with
the magnifying glass and sketch it. Remove the bit of stem and
dried-up calyx from the base of the fruit ; observe, above the calyx,
the knob or disk on which the pistil stood. Note with the magnify-
ing glass and count the minute whitish raised knobs at the bottom
of the saucer-shaped depression left by the removal of the disk.
What are they?
1 Fresh tomatoes, not too ripe, are to he used, or those which have been kept
over from the previous summer in formalin solution. The very smallest
varieties, such as are often sold for preserving, are better for study than the
larger kinds.
181182
ESSENTIALS OF BOTANY
Make a transverse section of the lemon, not more than a fifth of
the way down from the stigma end and note:
(1)	The thick skin, pale yellow near the outside, white within.
(2)	The more or less wedge-shaped divisions containing the juicy
pulp of the fruit. These are the matured cells of the ovary; count
these.
(3)	The thin partition between the cells.
(I) The central column or axis of white pithy tissue.
(5) The location and attachment of any seeds that may be
encountered in the section.
Make a sketch to illustrate these points, comparing it with
Fig. 141.
Study the section with the magnifying glass and note the little
spherical reservoirs near the outer part of the skin, which contain the
oil of lemon which gives to lemon peel its characteristic smell and
taste. Cut with a razor a thin slice from the surface of a lemon
peel, some distance below the section, and at once examine the
freshly cut surface with a magnifying glass to see the reservoirs,
still containing oil, which, however, soon evaporates. On the cut
surface of the pulp (in the original cross-section) note the tubes in
which the juice is contained. These tubes are not cells, but their
walls are built of cells. Cut a fresh section across the lemon about
midway of its length and sketch it, bringing out the same points
which were shown in the previous one. The fact that the number
of ovary cells in the fruit corresponds with the number of minute
knobs in the depression at its base is due to the fact that these
knobs mark the points at which fibro-vascular bundles passed from
the peduncle into the cells of the fruit, carrying the sap by ■which
the growth of the latter was maintained.
Note the toughness and thickness of the seed-coats. Taste the
kernel of the seed.
Cut a very thin slice from the surface of the skin, mount in
water, and examine with a medium power of the microscope.
Sketch the cellular structure shown and compare it with the sketch
of the corky layer of the hark of the potato tuber.
Of what use to the fruit is a corky layer in the skin ? (See
Sect. 243 for further questions.)THE STUDY OF TYPICAL FRUITS
183
216.	A Legume, the Bean-Pod.1 — Lay the pod flat on the table
and make a sketch of it, about natural size. Label stigma, style,
ovary, calyx, peduncle.
Make a longitudinal section of the pod at right angles to the
plane in which it lay as first sketched, and make a sketch of the
section, showing the partially developed seeds, the cavities in which
they lie, and the solid portion of the pod between each bean and the
nest.
Split another pod so as to leave all the beans lying undisturbed
on one-half of it, and sketch that half, showing the beans lying in
their natural position and the funiculus or stalk by which each is
attached to the placenta; compare Fig. 116.
Make a cross-section of another pod through one of the beans,
sketch the section, and label the placenta (formed by the united
edges of the pistil leaf) and the midrib of the pistil leaf.
Break off sections of the pod and determine, by observing where
the most stringy portions are found, where the fibro-vascular bundles
are most numerous.
Examine some ripe pods of the preceding year,2 and notice where
the dehiscence, or splitting open of the pods, occurs, whether down
the placental edge, ventral suture, the other edge, dorsal suture, or
both.
217.	An Akene, the Fruit of Dock. — Hold in the forceps a ripe
fruit of any of the common kinds of dock,3 and examine with the
magnifying glass. Note the three dry, veiny, membranaceous sepals
by which the fruit is enclosed. On the outside of one or more of
the sepals is found a tubercle or thickened appendage which looks
like a little seed or grain. Cut off the tubercles from several of the
fruits, put these, with some uninjured ones, to float in a pan of
water, and watch their behavior for several hours. What is appar-
ently the use of the tubercle?
1	Any species of bean (Phaseolus) will answer for this study. Specimens
in the condition known at the markets as “shell-beans” would be best, but
these may not be obtainable in spring. Ordinary “ string-beans ” will do.
2	Which may be passed round for that purpose. They should have been
saved and dried the preceding autumn.
3	Rumex crispus, R. obtusifolius, or R. verticillatus. This should have
been gathered and dried the preceding summer.184
ESSENTIALS OF BOTANY
Of what use are the sepals after drying up? Why do the fruits
cling to the plant long after ripening ?
Carefully remove the sepals and examine the fruit within them.
What is its color, size, and shape ? Make a sketch of it as seen with
the magnifying glass. Note the three tufted stigmas attached by
slender threads to the apex of the fruit. What does their tufted
shape indicate?
What evidence is there that this seed-like fruit is not really a
seed ?
Make a cross-section of a fruit and notice whether the wall of
the ovary can be seen distinct from the seed-coats. Compare the
dock fruit in this respect with the fruit of the buttercup shown in
Fig. 136. Such a fruit as either of these is called an akene.CHAPTER XIX
THE FRUIT1
218.	What constitutes a Fruit. — It is not easy to make
a short and simple definition of what botanists mean by
the term fruit. It has very little to do with the popular
use of the word. Briefly stated, the definition may be
given as follows: The fruit consists of the matured ovary
and contents, together with
any intimately connected
parts. Botanically speak-
ing, the bur of beggar's-ticks
(Fig. 148;, the three-cornered
grain of buckwheat, or such
true grains as wheat and
oats, are as much fruits as
is ail apple or a peach.
219.	Indehiscent and
Dehiscent Fruits. — All of
the fruits considered in the
next three sections are indehiscent, that is, they remain
closed after ripening. Dehiscent fruits when ripe open in
order to discharge their seeds; three modes of dehiscence
are shown in Fig. 146. The three classes which immedi-
ately follow Sect. '222, are all dehiscent.
1 See Gray’s Structural Botany, Chapter VII, also Kernel and Oliver’s
Natural History of Plants, Vol. II, pp. 427-438.
185
Fig. 136. Akenes of a Buttercup.
A, head of akenes; B, section of a
single akene (magnified), a, seed.186
ESSENTIALS OF BOTANY
Fig. 137. Chestnuts.
220.	The Akene. — The one-celled and one-seeded pistils
of the buttercup, strawberry, and many other flowers,
ripen into a little fruit called an akene (Fig. 186). Such
fruits, from their small size, their dry consistency, and
the fact that they never
open, are usually taken for
seeds by those who are not
botanists.
221.	The Grain.— Grains,
such as corn, wheat, oats,
barley, rice, and so on, have
the interior of the ovary com-
pletely filled by the seed,
and the seed-coats and the
wall of the ovary are firmly united, as shown in Fig. 6.
222.	The Nut. — A nut (Fig. 137) is larger than an
akene, usually has a harder shell, and commonly contains
a seed which springs from a single
ovule of one cell of a compound
ovary, which develops at the ex-
pense of all the other ovules. The
chestnut-bur is a kind of involucre,
and so is the acorn-cup. The name
nut is often incorrectly applied in
popular language; for example,
the so-called Brazil-nut is really a
large seed with a very hard testa.
223.	The Follicle. — One-celled,
simple pistils, like those of the
columbine or the monkshood, often produce a fruit which
dehisces along a single suture, usually the ventral one.
Such a fruit is called a follicle (Fig. 138).
Fig. 138. Group of Follicles
and a Single Follicle of the
Monkshood.THE FRUIT
187
224.	The Legume. — A legume is a one-celled pod
formed by the maturing of a simple pistil, which dehisces
along both of its sutures, as already seen in the case of
the bean pod, and illus-
trated in Fig. 146.
225.	The Capsule.—
The dehiscent fruit
formed by the ripening
of a compound pistil is
called a capsule. Such a
fruit may be one-celled,
as in the linear pod of
the celandine (Fig. 146),	1	11
,	,, ,	.	Fig. 139. Winged Fruits,
or several-celled, as in
I, elm; II, maple.
the fruit ol the poppy,
the morning-glory, and the jimson weed (Fig. 146).
226.	Dry Fruits and Fleshy Fruits-----In all the cases
discussed or described in Sects. 222-225, the wall of the
ovary (and the adherent calyx
when present) ripens into tis-
sues which are somewhat hard
and dry. Often, however,
these parts become developed
into a juicy or fleshy mass by
which the seed is surrounded;
hence a general division of
fruits into dry fruits and fleshy
fruits.
227. The Stone-Fruit. -— In
the peach, apricot, plum, and
cherry, the pericarp or wall of the ovary, during the
process of ripening, becomes converted into two kinds of
Fig. 140. Longitudinal
Section of a Peach.188
ESSENTIALS OF BOTANY
tissue, the outer portion pulpy and edible, the inner por-
tion of almost stony hardness. In common language the
hardened inner layer of the pericarp, enclosing the seed,
is called the stone (Fig. 140); hence the name stone-fruits.
228. The Pome. — The fruit of the apple, pear, and
quince is called a pome. It consists of an ovary of sev-
eral carpels—the seeds and
the tough membrane sur-
rounding them in the core
— enclosed by a fleshy, edi-
ble portion which makes up
the mam bulk of the fruit.
In the apple and the pear
much of the fruit is re-
ceptacle.
229. The Pepo or Gourd-
Fruit----In the squash,
pumpkin, cucumber, and all
of the species and varieties
of melons and gourds the
ripened ovary, together
with the thickened recep-
tacle, makes up a peculiar
fruit (with a firm outer
rind) known as the pepo. The relative bulk of greatly
enlarged hollow receptacle and of ovary in such fruits is
not always the same.
II ow does the amount of material derived from fleshy
and thickened placentas in the squash compare with that
in the watermelon?
230. The Berry. — The berry proper, such as the tomato,
grape, persimmon, gooseberry, currant, and so on, consists
o
Fig. 141. Cross-Section of
an Orange.
a, axis of fruit with dots showing cut-off
ends of fibro-vascular bundles; p, par-
tition between cells of ovary; S, seed;
c, cell of ovary filled with a pulp com-
posed of irregular tubes full of juice;
o, oil reservoirs near outer surface of
rind; e, corky layer of epidermis.THE FRUIT
189
of a rather thin-skinned, one- to several-celled, fleshy ovary
and its contents. In the first three cases above mentioned
the calyx forms no part of the fruit, but it does in the last
two, and in a great number of berries.
The gourd-fruit and the hesperidium, such as the orange
(Fig. Ill), lemon, and lime, are merely decided modifica-
tions of the berry proper.
231. Aggregate Fruits.—The raspberry (Fig. 112),
blackberry, and similar fruits consist of many carpels, each
I	II	III
Fig. 142. I, Strawberry; II, Raspberry ; III, Mulberry.
of which ripens into a part of a compound mass, which,
for a time at least, clings to the receptacle. The whole
is called an aggregate ftuit.
What is the most important difference in structure
between a fully ripened raspberry and a blackberry ?
232. Accessory Fruits and Multiple Fruits.—Not infre-
quently, as in the strawberry (Fig. 112), the main bulk of
the so-called fruit consists neither of the ripened ovary
nor its appendages. Such a combination is called an
accessory fruit.
Examine with a magnifying glass the surface of a small unripe
strawberry, then that of a ripe one, and finally a section of a ripe190
ESSENTIALS OF BOTANY
one, and decide where the separate fruits of the strawberry are found,
what kind of fruits they are, and of what the main bulk of the straw-
berry consists.
The fruits of two or more separate flowers may blend into
a single mass, which is known as a multiple fruit. Perhaps
the best-known edible examples of this are the mulberry
(Fig. 142) and the pineapple. The last-named fruit is an
excellent instance of the seedless condition which not
infrequently results from long-continued cultivation.
233. Summary. — The student may find it easier to
retain what knowledge he has gained in regard to fruits if
he copies the following synopsis of the classification of
fruits, and gives an example of each kind.
composition .
simple.
aggregate.
accessory.
multiple.
texture .	.
<
fleshy
stone
Fruits
1
o
dry .
3
4
mode of disseminat-
ing seed ....
indehiscent
dehiscent .CHAPTER XX
ECOLOGY OF FRUITS; DISPERSAL OF FRUITS AND SEEDS
234.	Subjects of the Chapter. — The ecology of fruits and
seeds is concerned mainly with the various means by which
seeds are protected from decay or from being destroyed by
animals, and the methods by which they are enabled to
secure transportation and to become planted in localities
suitable for their growth. The latter topic, that of seed
distribution, is the one which will be discussed in this
chapter.
235.	Dispersal of Seeds.—Seeds are not infrequently
scattered by apparatus by which the plant throws them
about. More commonly, however, they depend upon other
agencies, such as wind, water, or animals, to carry them.
Sometimes the transportation of seeds is due to the struc-
ture of the seeds themselves, sometimes to that of the
fruit in which they are enclosed; the essential point is to
have transportation to a long distance made as certain as
possible, to avoid overcrowding.
236.	Explosive Fruits. — Some dry fruits burst open
when ripe in such a way as to throw their seeds violently
about. Interesting studies may be made, in the proper
season, of the fruits of the common blue violet, the
pansy, the wild balsam, the garden balsam, the cranes-
bill, the herb Robert, the witch-hazel, the Jersey tea, and
some other common plants. The capsule of the tropical
191192
ESSENTIALS OF BOTANY
American sand-box tree bursts open when thoroughly dry
with a noise like that of a pistol shot.
237. Winged or Tufted Fruits and Seeds. — The fruits
of the ash, box-elder, elm, maple (Fig. 139), and many
other trees are provided with an expanded membranous
wing. Some seeds, as those of the catalpa and the trum-
pet-creeper, are similarly appendaged. The fruits of the
dandelion, the thistle, the fleabane, and many other plants
of the group to which
these belong, and the
seeds of the willow,
the milkweed (Ancle-
pias), the willow-herb,
and other plants bear
a tuft of hairs.
The student should be
able, from his own ob-
servations on the falling
fruits of some of the trees
and other plants above
mentioned, to answer
Fig. 143. Fruits of Linden, with a Bract joined such questions as the
to the Peduncle and forming a Wing. following.
What is the use of the
wing-like appendages? of the tufts of hairs?
Which set of contrivances seems to be the more successful of the
two in securing this object?
What particular plant of the ones available for study seems to
have attained this object most perfectly?
What is one reason why many plants with tufted fruits, such as
the thistle and the dandelion, are extremely troublesome weeds?
A few simple experiments, easily devised by the student, may help
him to find answers to the questions above given.1
1 See Kerner and Oliver, Vol. II, pp. 833-875; also Beal’s Seed Dispersal.Plate X. Thistle Fruits, adapted for Dispersal by the
Wind.ECOLOGY OF FRUITS
193
238. Tumbleweeds. — Late in the autumn, fences, par-
ticularly on prairie farms that are not carefully tilled,
often serve as lodging-places for
immense numbers of certain dried-
up plants known as tumbleweeds.
These blow about over the level
surface until the first snow falls
Fig. 14-1. Russian Thistle.
and even after that, often
traveling for many miles be-
fore they come to a stop, and
rattling out seeds as they
go. Some of the commonest
tumbleweeds are the Russian
thistle (Fig. 144), the pig-
weed (Amarantus grcecizans), the tickle-grass (Fig. 145), and
a familiar pepper-grass (Lepidium). In order to make a
Fig. 115. Panicle of Tickle-Grass,
a Common Tumbleweed.194
ESSENTIALS OF BOTANY
successful tumbleweed, a plant must be pretty nearly
globular in form when fully grown and dried, must be
tough and light, must break off near the ground, and
drop its seeds only a few at a time as it travels. A
single plant of Russian thistle is sometimes as much as
three feet high and six feet in diameter and carries not
less than two hundred thousand seeds.
239. Many-Seeded Pods with Small Openings. — There
are many fruits which act somewhat like pepper-boxes.
Fig. 146. Three Fruits adapted for Dispersal by the Shaking
Action of the Wind.
I, celandine; II, pea; III, jimson weed (Datura).
The capsule of the poppy is a good instance of this kind,
and the fruit of the lily, monkshood (Fig. 138), columbine,
larkspur, and jimson weed (Fig. 146) acts in much the
same way. Clamping the dry peduncle of any one of
these ripe fruits, so as to hold it upright above the table-
top, and then swinging it back and forth, will readily
show its efficiency in seed dispersal.ECOLOGY OF FRUITS
195
240.	Study of Transportation by Water. — Nothing less
than a long series of observations by the pond-margin and
the brookside will suffice to show how general and impor-
tant is the work done by water in carrying the seeds of
aquatics. An experiment will, however, throw some light
on the subject.
EXPERIMENT XX
Adaptation for Transportation by Water. — Collect fruits of as
many aquatic, semi-aquatic, or riverside and brookside species of
plants as possible, place them on shallow pans of water, and notice
what proportion of all the kinds studied will float. Leave them
twenty-four hours or more and see whether all the kinds that floated
at first are still afloat. Some desirable fruits for this experiment
are aquatic grasses, rushes and sedges, polygonums, water-dock,
bur-reed, arrowhead, water-plantain, pickerel-weed, alder, button-
bush, water-parsnip (Sium), water-hemlock (Ci'cuta), water penny-
wort (Hydrocotyle), lotus (Nelumbo).
241.	Distances traversed by Floating Seeds. — Ocean
currents furnish transportation for the longest journeys
that are made by floating seeds. It is a well-known fact
that cocoa-palms are among the first plants to spring up
on newly formed coral islands. The nuts from which
these palms grew may readily have floated a thousand
miles or more without injury. On examining a cocoanut
with a fibrous husk attached, just as it fell from the tree,
it is easy to see how well this fruit is adapted for trans-
portation by water. There are altogether about a hundred
drifting fruits known, one (the Mai dive nut) reaching a
weight of from twenty to twenty-five pounds.
242.	Burs____A large class of fruits is characterized by
the presence of hooks on the outer surface. These are196
ESSENTIALS OF BOTANY
sometimes outgrowths from the ovary, sometimes from
the calyx, sometimes from an involucre. Their office is
to attach the fruit to the hair or fur of passing animals.
Often, as in sticktights (Fig. 117), the hooks are com-
paratively weak, but in other cases, as in the cockle-
bur (Fig. 117), and still more in the Martynia, the fruit of
A, sticktights; B, sticktights, two segments (magnified);
C\ burdock; D, cockleburs.
which in the green condition is much used for pickles, the
hooks are exceedingly strong. Cockleburs can hardly be
removed from the tails of horses and cattle, into which
they have become matted, without cutting out all the hairs
to which they are fastened.
Why do bur-bearing plants often carry their fruit until
late winter or early spring?ECOLOGY OF FRUITS
197
What reason can be given for the fact that the burdock,
the cocklebur, the beggar’s-ticks, the hound's-tongue, and
many other common burs are among the most persistent
of weeds?
243. Uses of Stone-Fruits and Fleshy Fruits to the Plant.
— Besides the dry fruits, of which some of the principal
I, barbed points from fruit of beggar’s-ticks (magnified eleven times);
II, hook of cocklebur (magnified eleven times); III, beggar's-ticks
fruit (natural size); IV, cocklebur hook (natural size).
amount of sugar and other food material which they con-
tain is very considerable. It is a well-recognized principle
of botany, and of zoology as well, that plants and animals
do not make unrewarded outlays for the benefit of other
species. Evidently the pulp of fruits is not to be consumed
or used as food by the plant itself or (in general) by its198
ESSENTIALS OF BOTANY
seeds. It is worth while, therefore, for the student to ask
himself some such questions as these:1
(1)	Why is the pulp of so many fruits eatable ?
(2)	Why are the seeds of many pulpy fruits bitter or
otherwise unpleasantly flavored, as in the orange?
(3)	Why are the seeds or the layers surrounding the
seeds of many pulpy fruits too hard to be chewed, or
digested, as in the date and the peach?
(4)	Why are the seeds of some pulpy fruits too small
to be easily chewed, and also indigestible, as in the fig
and the currant?
(5)	Account for the not infrequent presence of currant
bushes or asparagus plants in such localities as the forks
of large trees, sometimes at a height of twenty, thirty, or
more feet above the ground.
Careful observation of the neighborhood of peach, plum,
cherry, or apple trees at the season when the fruit is ripe
and again during the following spring, and an examina-
tion into the distribution of wild apple or pear trees in
pastures where they occur, will help the student who can
make such observations to answer the preceding questions.
So, too, would an examination of the habits of fruit-eating
quadrupeds and of the crop and gizzard of fruiLeating
birds during the season when the fruits upon which they
feed are ripe.	*
244. Seed-Carrying purposely done by Animals. — In the
cases referred to in the preceding sections, animals have
been seen to act as unconscious or even unwilling seed-
carriers. Sometimes, however, they carry off seeds with
the plan of storing them for food. Ants drag away with
1 See Kcrner and Oliver’s Natural History of Plants, Vol. II, pp. 442-450.ECOLOGY OF FRUITS
199
them to their nests certain seeds which have fleshy growths
on their outer surfaces. Afterwards they eat these fleshy
parts at their leisure, leaving the seed perfectly fit to grow,
as it often does.1
Fig. 119. Seed of Bloodroot with Caruncle or Crest, which serves as
a Handle for Ants to hold on to. Ant ready to take the seed.
Squirrels and bluejays are known to carry nuts and
acorns about and bury them for future use. These
deposits are often forgotten and so get a chance to grow,
and in this way a good deal of tree-planting is done.
1 See Beal’s Seed Dispersal, pp. 69, 70.CHAPTER XXI
THE STRUGGLE FOR EXISTENCE AND THE SURVIVAL
OF THE FITTEST 1
245. Weeds. — Any flowering plant which is trouble-
some to the farmer or gardener is commonly known as
a weed. Though such plants are annoying from their
tendency to crowd out others useful to man, they are of
extreme interest to the botanist on account of this very
hardiness. The principal characteristics of the most suc-
cessful weeds are their ability to live in a variety of soils
and exjuosures, their rapid growth, resistance to frost,
drought, and dust, their unfitness for the food of most of
the larger animals, in many cases their capacity to accom-
plish self-pollination in default of cross-pollination, and
their ability to produce many seeds and to secure their
wide dispersal. Not every weed combines all of these
characteristics. For instance, the velvet-leaf or butter-
print,2 common in cornfields, is very easily destroyed by
frost; the pigweed and purslane are greedily eaten by
pigs, and the ragweed by some horses. The horse-radish
does not usually produce any seeds.
It is a curious fact that many plants which have finally
proved to be noxious weeds have been purposely introduced
into the country. The fuller's teasel, melilot, horse-radish,
1	See Darwin’s Origin of Species, Chapters III and IV.
2	Abutilon Fheophrasti.
200THE STRUGGLE FOR EXISTENCE
201
wild carrot, wild parsnip, tansy, oxeye daisy, and field-garlic
are only a few of the many examples of very troublesome
weeds which were at first planted for use or for ornament.
246.	Origin of Weeds.1 — By far the larger proportion
of our weeds are not native to this country. Some have
been bi'ought from South America and from Asia, but
most of the introduced kinds come from Europe. The
importation of various kinds of grain and of garden-seeds,
mixed with seeds of European weeds, will account for the
presence of many of the latter among us. Others have
been brought over in the ballast of vessels. Once landed,
European weeds have succeeded in establishing themselves
in so many cases, because they were superior in vitality
and in their power of reproduction to our native plants.
This may not improbably be due to the fact that the Euro-
pean and western Asiatic vegetation, much of it consisting
from very early times of plants growing in comparatively
treeless plains, has for ages been habituated to flourish in
cultivated ground and to contend with the crops which
are tilled there.
247.	Plant Life maintained under Difficulties. — Plants
usually have to encounter many obstacles even to their
bare existence. For every plant which succeeds in reach-
ing maturity and producing a crop of spores or of seeds
there are hundreds or thousands of failures, as it is easy
to show by calculation. The morning-glory (Ipomcea pur-
purea) is only a moderately prolific plant, producing, in an
ordinary soil, somewhat more than three thousand seeds.2
If all these seeds were planted and grew, there would
1	See the article Pertinacity and Predominance of Weeds, in Scientific
Papers of Asa Gray, selected by C. S. Sargent, Yol. II, pp. 2.14-242.
2	Rather more than three thousand two hundred by actual count and
estimation.202
ESSENTIALS OF BOTANY
be three thousand plants the second summer sprung from
the single parent plant. Suppose each of these plants to
bear as the parent did, and so on, then there would be:
9,000,000 plants the third year.
27,000,000,000 plants the fourth year.
81,000,000,000,000 plants the fifth year.
248,000,000,000,000,000 plants the sixth year.
729,000,000,000,000,000,000 plants the seventh year.
It is not difficult to see that the offspring of a single
morning-glory plant would, at this rate, soon actually
cover the entire surface of the earth. The fact that
morning-glories do not occupy any larger amount of ter-
ritory than they do must therefore depend upon the fact
that the immense majority of their seeds are not allowed
to grow into mature plants.
There are many plants which would yield far more sur-
prising results in a calculation similar to that just given
than are afforded by the morning-glory. For instance, a
foxglove capsule contains on an average nearly 1800 seeds.
A small foxglove plant bears from 140 to 200 capsules
and a large one from 530 to 700. Therefore a single
plant may produce over 1,250,000 seeds. A single orchid
plant1 has been shown to produce over 10,000,000 seeds.
248. Importance of Dispersal of Seeds. — It is clear that
any means of securing the wide distribution of seeds is of
vital importance in continuing and increasing the numbers
of any kind of plant, since in this way destruction by over-
crowding and starvation will be lessened.
A few of the means of transportation of seeds have been
described in Sects. 235-244, but the cases are so numerous
1 Maxillaria; see Darwin’s Fertilization of Orchids, Chapter IXTHE STRUGGLE FOR EXISTENCE
203
and varied that a special treatise might well be devoted to
this subject alone.
249.	Destruction of Plants by Unfavorable Climates. —
Land-plants throughout the greater part of the earth’s
surface are killed in enormous numbers by excessive heat
and drought, by floods, or by frost. After a very dry
spring or summer the scantiness of the crops, before the
era of railroads which nowadays enable food to be brought
in rapidly from other regions, often produced actual fam-
ine. Wild plants are not observed so carefully as culti-
vated ones are, but almost every one has noticed the
patches of grass, apparently dead, in pastures and the
withered herbaceous plants everywhere through the fields
and woods after a long drought.
Floods destroy the plants over large areas by drowning
them, by sweeping them bodily away, or by covering them
with sand and gravel. Frosts kill many annual plants
before they have ripened their seeds, and severe and
changeable winters sometimes kill perennial plants.
250.	Destruction by Other Plants. -— Overcrowding is
one of the commonest ways in which plants get rid of
their weaker neighbors. If the market-gardener sows his
lettuce or his beets too thickly, few perfect plants will be
produced, and the same kind of effect is brought about in
nature on an immense scale. Sometimes plants are over-
shadowed and stunted or killed by the growth all about
them of others of the same kind; sometimes it is plants
of other kinds that crowd less hardy ones out of existence.
Whole tribes of parasitic plants, some comparatively
large, like the dodder and the mistletoe, others micro-
scopic, like blights and mildews, prey during their entire
lives upon other plants.204
ESSENTIALS OF BOTANY
251.	Adaptations to meet Adverse Conditions.—Since
there are so many kinds of difficulties to be met before the
seed can grow into a mature plant and produce seed in
its turn, and since the earth’s surface offers such extreme
variations as regards heat, sunlight, rainfall, and quality
of soil, it is evident that there is a great opportunity
offered for competition among plants. Of several plants
of the same kind, growing side by side, where there is
room for but one full-grown one, all may be stunted, or
one may develop more rapidly than the others, starve them
out, and shade them to death. Of two plants of different
kinds, the hardier will crowd out the less hardy, as ragweed,
pigweed, and purslane do with ordinary garden crops.
Weeds like these are rapid growers, stand drought or
shade well, will bear to be trampled on, and, in general,
show remarkable toughness of organization.
Plants which can live under conditions that would be
fatal to most others will find much less competition than
the rank and file of plants are forced to encounter. Lichens
growing on barren rocks are thus situated, and so are the
numerous species of blue-green algae (Sect. 277) which are
found growing in hot springs, as in those of the Yellow-
stone National Park, at temperatures of 140° or more.
252.	Examples of Rapid Increase. — Nothing but the
opposition which plants encounter from overcrowding or
from the attacks of their enemies prevents any hardy kind
of plant from covering all suitable portions of a whole
continent, to the exclusion of most other vegetable life.
New Zealand and the pampas of La Plata and Paraguay,
in South America, have, during the present century, fur-
nished wonderful examples of the spread of European
species of plants over hundreds of thousands of squareSURVIVAL OF THE FITTEST
205
miles of territory. The newcomers were more vigorous, or
in some way better adapted to get on in the world, than
the native plants which they encountered, and so managed
to crowd multitudes of the latter out of existence.
In our own country a noteworthy case of the kind has
occurred so recently that it is of especial interest to Ameri-
can botanists. The so-called Russian thistle (Fig. 144),
Salsola Kali, var. teuuifolia, a variety of the saltwort of
the Atlantic coast, was first introduced into South Dakota
in flaxseed brought from Russia and planted in 1873 or
1874. In twenty years from that time the plant had be-
come one of the most formidable weeds known over an
area of about twenty-five thousand square miles.
253.	Importance of Adaptiveness in Plants. — It may be
inferred from the preceding sections that a premium is set
on all changes in structure or habits which may enable
plants to resist their living enemies or to live amid partially
adverse surroundings of soil or climate. It would take a
volume to state, even in a very simple way, the conclusions
which naturalists have drawn from this fact of a savage
competition going on among living things, and it will be
enough to say here that the existing kinds of plants to a
great degree owe their structure and habits to the operation
of the struggle for existence, this term including the effort to
respond to changes in the conditions by which they are sur-
rounded. How the struggle for existence has brought
about such far-reaching results will be briefly indicated in
the next section.
254.	Survival of the Fittest. — When frost, drought,
blights, or other agencies kill most of the plants in any
portion of the country, it is often the case that many of
the plants which escape do so because they can stand more206
ESSENTIALS OF BOTANY
hardship than the ones which die. In this way delicate
individuals are weeded out and those which are more
robust survive. One shellbark hickory bears nuts whose
shell is easily cracked by hogs, while another protects its
seeds by a shell so hard that it is cracked only by a pretty
heavy blow. In case of all such differences, there is a
strong tendency to have the less eatable fruit or seed
preserved and allowed to grow, while the more eatable
varieties will be destroyed. The result of this kind cf
advantage, in any of its countless forms, is sometimes
called survival of the fittest, and sometimes natural selec-
tion. The latter name means only that the outcome of
the process just described, as it goes on in nature, is much
the same as that of the seed grower’s selection, when, by
picking out year by year the sweetest sugar-beets or the
most nearly “ stringless ” beans, he obtains permanent
new varieties. To obtain new species, though possible,
would be more difficult, for these are divided from each
other by greater differences than those which distinguish
varieties from varieties (Sects. 256, 258). It has recently
been proved by Professor Hugo de Vries, of Amsterdam,
Holland, that while all plants, from generation to genera-
tion, show variations, sometimes -they show mutations as
well. A mutation is a sudden, marked change, a sort of
leap, such as the growth of pecan trees from hickory nuts or
of pansies from the seed of common blue violets would be.
None of the observed mutations in plants have been as con-
spicuous as those above suggested, but to the botanist they
are quite as remarkable. Since new species produced by
mutation continue to reproduce themselves, many species
may, in the course of ages, have been thus produced from
a few ancestral forms.CHAPTER XXII
THE CLASSIFICATION OF PLANTS1
255.	Natural Groups of Plants. — One does not need
to be a botanist in order to recognize the fact that plants
naturally fall into groups which resemble each other pretty
closely, that these groups may be combined into larger ones
the members of which are somewhat alike, and so on. For
example, all buttercups belong to the same division or genus.
The marsh marigold, the hepatica, the rue anemone, and
the anemone all have a family resemblance to buttercups,
and the various anemones by themselves form another group
like that of the buttercups.
256.	Genus and Species. — Such a group as that of the
buttercups is called a genus (plural genera), while the vari-
ous kinds of buttercups of which it is composed are called
species. The scientific name of a plant is that of the genus
followed by that of the species. The generic name begins
with a capital, the specific does not unless it is derived from
the name of a person or the name of a genus. After the
name comes the abbreviation for the name of the botanist
who is authority for it; thus the common elder is Sambucus
canadensis L., L. standing for Linnteus. Familiar examples
of genera are the Violet genus, the Rose genus, the Oak
1 See Warming-Mbbius’s Handbuch dor systematischen Botanik, Born-
trseger, Berlin; Strasburger, Noll, Schenk, andKarsten’s Text-Book of Botany,
Part II, Macmillan, New York; or Engler’s Syllabus der Pfianzenfamilien,
Engelmann, Leipzig.
207208
ESSENTIALS OF BOTANY
genus. The number of species in a genus varies widely, —
the Kentucky Coffee-tree genus contains only one species,
while the Clolden-rod genus comprises more than forty
species in the northeastern United States alone.
257.	Hybrids. — If the pollen of a plant of one species
is placed on the stigma of a plant of the same genus but a
different species, no fertilization will usually occur. In
a large number of cases, however, ovules will be fertilized
and good seed be produced. This process is called hybridi-
zation, and any plant grown from such seed is a hybrid.1
Many hybrid oaks and violets have been found to occur
in a state of nature, and hybrid forms of wheat, orchids,
grapes, and other cultivated plants are produced by plant
breeders at will (Chapter xxix).
258.	Varieties. — Oftentimes it is desirable to describe
and give names to subdivisions of species. All the culti-
vated kinds of apple are reckoned as belonging to one
species, but it is convenient to designate such varieties as
the Baldwin, the Bellflower, the Rarnbo, the Gravenstein,
the Northern Spy, and so on.
259.	Family. — Genera which resemble each other some-
what closely are classed together in one family. The
particular genera mentioned in Sect. 255, together with a
large number of others, combine to make up the Buttercup
family. In determining the classification of plants most
points of structure are important, but (in the case of seed-
plants) the characteristics of the flower and fruit outrank
others because they are more constant, since they vary
less rapidly than the characteristics of roots, stems, and
leaves do under changed conditions of soil, climate, or other
surrounding circumstances. Mere size or habit of growth
1 See L. H. Bailey’s Plant Breeding, The Macmillan Company, New York.THE CLASSIFICATION OF PLANTS
209
has nothing to do with the matter, so the botanist finds no
difficulty in recognizing the strawberry plant and the apple
tree as members of the same family.
This family affords excellent illustrations of the meaning
of the terms genus, species, and so on. The Rose family con-
tains (among many others) the Pear genus, which contains
the apple species, which contains the greening variety.
260. Grouping of Families. — Families are assembled
into orders and these again into larger groups. The prin-
cipal names of groups used in classification, beginning with
the highest, are as follows:
Plant Kingdom.
Division.
Series.
Class.
Order.
Family.
Genus.
Species.
Variety.
The entire plant kingdom may be divided into four
grand divisions and these into lesser groups, as shown in
the table on page 210. This table is for reference only. It
serves in a general way to represent the progress of plant
development, beginning with the lowest (and oldest) types
and proceeding to the highest. The algte and fungi should,
however, be placed parallel to each other and not in series,
since the latter are distinguished from the former mainly
by their parasitic or saphrophytic mode of life and the
modifications due to this. No perfect scheme of classifi-
cation has yet been made out and the highest authorities
differ in regard to details of classification.210
ESSENTIALS OF BOTANY
261. Outline of Classification.
DIVISION I. Tliallophyta, thallus plants.
Series of the Ai.g.e.
Class 1. Cyanophycece, blue-green algse.
“	2.	Diatomacece, diatoms.
“	3.	Conjugate, conjugating algae.
“	4.	Chlorophyceie, green algse.
“	5.	Phmophycece, brown algse.
“	6.	ffliodopliycece, red algse.
Series of the Fungi.
Class 7. Schizomycetes, bacteria.
“	8. Saccharomycetes, yeasts.
“	9.	Pliycomycetes, algal fungi.
“	10.	Ascomycetes,,sac fungi.
“	11.	Basidiomycetes, basidia fungi.
DIVISION II. Bryopliyta, liverworts and mosses.
Class	1.	Hepaticce, liverworts.
“	2.	Musci, mosses.
DIVISION III. Pteridophyta, ferns and their allies.
Class	1.	Filicinew, true ferns.
“	2.	Equisetinece, horsetails.
“	3.	Lycopodinece, club mosses.
DIVISION IV. Spermatophyta, seed-plants.
Subdivision I. Gymnospermce.
Subdivision II. Angiospermce.1
Class 1. Monocotyledonecc, or Monocotyledons (divided into
11 orders).
“	2. Dicolyledonece, or Dicotyledons.”'
Subclass 1. Choripetalous plants (divided into 28 orders).
Subclass 2. Sympetalous plants (divided into 8 orders).
1 Note that the angiosperms or non-coniferous seed-plants, making up the
immense majority of what are ordinarily known as flowering plants, only
comprise two out of the eighteen classes of plants here outlined. Many of
the very lowest forms of life, which combine some of the characteristics of
animals and plants, are omitted from this table.CHAPTER XXIII
CHARACTERISTICS OF SPORE-PLANTS
262.	Definition of a Spore-Plant. — A spore-plant is one
which does not form seeds but is reproduced by means of
a one-celled reproductive body called a spore.1 Such bodies
do not contain an embryo ; they are of microscopic size and
in all ways are far simpler than seeds.
263.	Diversity among Spore-Plants. — Spore-plants are
extremely diverse in their size, structure, and life habits,
and in the details of their reproductive processes.
The simplest and smallest among them are one-celled
organisms, not more than a fifty-thousandth of an inch in
diameter, while the largest seaweeds are nearly or quite a
thousand feet in length, and tree ferns reach a height of
thirty or forty feet, with ample spreading crowns (Plate XI).
The pale or colorless spore-plants, such as bacteria,
molds, and toadstools or mushrooms (Figs. 169,172,185),
can live only as parasites, taking their food from living
animals or plants, or as saprophytes, feeding on the prod-
ucts of decay.
The green spore-plants, however, carry on their nutritive
processes as the higher plants do (Chapter xm), and in
all such relatively complex forms as the horsetails and
1 Seed-plants (commonly called flowering plants) also produce spores (Sect.
383), but those forms which are treated in Chapters XXIII-XXYII may fairly
be called spore-plants since the spore is their highest means of reproduction.
211212
ESSENTIALS OF BOTANY
the ferns, the arrangements for respiration, photosynthesis
(Sect. 163), and transpiration are very complete.
The student can obtain a reasonably thorough knowl-
edge of the lower plants only by a prolonged study of
many types. It is possible, however, to get some idea
of their general appearance by a rapid examination of
some characteristic forms.
264.	Examination of Yeast. — Obtain some growing yeast-cells
from compressed yeast mixed with molasses and water. Put a very
small drop of the liquid on a slide, cover with a cover-glass, and examine
with h.p. (high power).1 Note the apparent size, shape, contents, and
characteristics of the cells. Each cell is a yeast plant. Their actual
diameter averages about one three-thousandth of an inch. Lacking
chlorophyll they are Incapable of making food by photosynthesis (Sect.
163) and live on the substances in which they cause fermentation.
265.	Examination of Pleurococcus. — Collect some of the green
coating which is usually found on the north sides of tree trunks or
unpainted fences. Place a few flakes of bark or bits of wood with,
their green covering in a plate, moisten with water, cover with a bell-
glass, and leave for two or three days in a warm, sunny place. Scrape
off a minute portion of the green coatin g, mount in water, and exam-
ine, first with m.p. (medium power) and then with h.p. (high power).
Note the single cells and grouped cells. Each cell is a Pleurococcus
plant. The groups result from cell division, and the plant reproduces
itself freely in this way. Make a careful drawing to show the shapes
of isolated cells and of some groups. Pleurococcus contains abundant
chlorophyll and produces plant food by photosynthesis.
266.	Examination of Cladophora.2—Study living or preserved mate-
rial in a little water in a white saucer by aid of a magnifying glass.
Mount a very small portion in a drop of water on a slide, cover with a
cover-glass, and examine with m.p. Note the shape of the filaments
1	Throughout this and subsequent chapters the powers of the microscope
will be referred to as i.p., m.p., and h.p., meaning respectively low power,
medium power, and high power (see Appendix II).
2	Any filamentous green alga such as Ziignemu, Mesocarpus, Stigeoclonium,
or Broparnaldia will answer. See Bergen and Davis’ Principles of Botany,
Chapter XX, Giun & Company.CHARACTERISTICS OF SPORE-PLANTS
213
and whether or no they branch. Make a habit sketch to show all that
you can of the general appearance of the plant. With the h.p. note
the exact form and mode of connection of the cells of which the fila-
ments are composed, and the size and shape of the chlorophyll bodies.
In the group to which Cladophora belongs these are often band-shaped,
star-shaped, or tabular and comparatively large. Make a careful draw-
ing to show these points. Plants of this group are more complex than
Pleurococcus; but their nutrition is not of a higher character.
267.	Examination of a Moss-Plant. — Study any convenient leafy
moss-plant (best in a fresh condition) with the magnifying glass.
Note the root-like fibers, the stem, and leaves. How are the leaves
arranged ? Examine a leaf in water with m.p. and note whether it
consists of one or more layers of cells. Describe the chlorophyll
bodies. Examine the stem for woody fibers. State several respects
in which the moss-plant seems more highly organized than any of
the spore-plants discussed in Sects. 264-266. Its leaves are well
adapted for photosynthesis.
268.	Examination of a Fern.1 — Note the division of the fern into
underground portion (rootstock and roots) and aerial portion (leaves,
with or without a stem). Describe the leaves and note how their rein-
ing differs from that of seed-plants. Look on the under surface of
the leaves for spore-bearing regions, usually brown in color (Fig. 204).
If any are found, describe exactly their location. Strip off a bit of
the lower epidermis of a leaf, mount, and examine it with m.p. for
stomata. Look for woody fibers in the stem. The fern is nearly
as well equipped for photosynthesis and for transmission of water
through the stem as are most seed-plants.
269.	Summary. — The student has made a hasty exam-
ination of five types of spore-plants not including the
very lowest nor the very highest. Discussion of their
modes of reproduction has purposely been omitted, as the
object of these simple studies has been merely to obtain
some idea of the shape and structure of a few spore-plants
in their vegetative condition.
1 Any kind of terrestrial fern except the genus chosen for study in Sects.
362-364.214
ESSENTIALS OF BOTANY
From the types discussed it is evident that in the case
of yeast and Pleurococcus a cell is an individual plant. In
Cladophora and many other thread-like genera either one
cell of a filament or a straight or branching row of similar
cells is an individual. In the mosses, ferns, and still more
highly developed types the plant is composed of many
layers of cells, which have assumed various forms to fit
them for their several duties.
270. Series of Spore-Plants. — The spore-plants are
grouped in three grand divisions, or series, as follows:1
Series I. Thallophytes.2 One-celled or several to many-
celled plants of very simple organization, usually without
separate root, stem, and leaves, always without fibro-vas-
cular bundles.
Series II. Bryophytes, or liverworts and mosses. Small
plants which sometimes consist merely of a nearly flat mass
of cellular tissue sometimes have a leafy stem, but are
always without true roots or fibro-vascular bundles. The
method of reproduction is of a far more advanced char-
acter than in Series I.
Series III. Pteridophytes, or ferns, horsetails, and club
mosses. Plants, some of them small, others large, with
true roots, stems, and leaves, and with fibro-vascular bun-
dles (although the vessels have not exactly the structure of
those in seed-plants). The method of reproduction is still
more advanced than in Series II.
1	See p. 210. This section should not he studied in detail until the discus^
sion of pteridophytes (Chapter XXVII) is completed.
2	This is a rather miscellaneous group and the name is somewhat misleading,
as some bryophytes also have a plant body consisting only of a flat tliaflus.CHAPTER XXIY
THE A LG® 1
271.	Definition ; Occurrence. — The algce comprise all of
the plants below the liverworts and mosses with the capacity
for photosyn thesis. They constitute a series of the division
Thallophyta (see Sect. 261).
Most algee are aquatic, some inhabiting fresh and others
salt water, but a few groups flourish in merely damp situa-
tions, such as on moist earth, bark, or wood. Still others
(constituting the photosynthetic part of lichens) grow in
partnership with certain fungi (Sect. 327).
272.	Classes of Algae.—Algrn are divided, mainly on
the basis of their modes of reproduction, into six great
groups, as follows:
Class 1. Blue-green algae, Cyanophycece.
“	2.	Diatoms, Diatomacece.
“	3.	Conjugating algae, Conjugates.
“	4.	Green algae, Chlorophycea:.
“	5.	Brown algae, Phceophycece.
“	(5.	Red algae, Rhodophyceos.
The color, though not a basis of classification, forms a
very convenient means of naming and roughly distinguish-
ing some of the groups; it does not, however, serve to
distinguish Class 3 from Class 4.
1 See Bergen and Davis’ Principles of Botany and Whipple’s Microscopy
of Drinking Water, Wiley & Sons, New York.
215216
ESSENTIALS OF BOTANY
OSCILLATORIA, — ONE OF THE BLUE-GREEN ALGA3
273.	Occurrence. — Oscillatoria may occur floating in
stagnant water, about watering troughs or outlets of drains
and sewers, or on pots in greenhouses. In general it flour-
ishes in the presence of dissolved and decajdng organic
matter.
274.	Gross Structure. — Examine with the magnifying glass a bit
taken from a growing mass of the plant and left for some hours in
a white saucer with a little water. Note :
(a)	The color.
(b)	The filaments radiating from the
rather compact mass of the plants.
275. Minute Structure. — With m.p.
note:
(a) The shape of the filaments. Are
they branched ?
(?<) Their movements. Describe these.
Sketch several filaments.
With h.p. note :
(e) The shape of the tip of a filament.
(d)	The coin-shaped cells of which the
filaments are made up.
(e)	The occasional occurrence of a dead
cell, leaving a transparent place in the
filament.
(/) The delicate sheath inclosing the filament (best seen where
a dead cell occurs). Make a careful drawing showing the points
(c, d, e,f) above mentioned.
276. Discussion. — Oscillatoria is a plant of very low
organization, marked, for example, by the absence of a
well-defined nucleus in the unit cells of which the fila-
ments are composed. Each cell is an individual plant,
although, as the student has seen for himself, they live in
communities. The flattened form of the cells is evidently
Fig. 150. Gloeocajisa, one
of the Lowest of the Blue-
Green Algse. (x 300.)
A-E, successive stages in the
development of new indi-
viduals from a parent-cell.THE ALGJE
217
due to the pressure exerted upon each by its neighbors,
since at the tips of the filaments and on each side of a
dead cell the unopposed pressure of the protoplasm causes
the cell-walls to become con-
vex (see Sect. 280).
Oscillatoria contains
abundant coloring matter of
a bright bluish green or steel
blue. If a small quantity
of dried Oscillatoria is pul-
verized and then soaked in
water, the water is colored
blue by the pigment which
it extracts from the cell-
contents. The residue may
then be treated with alcohol,
which becomes green from
the chlorophyll dissolved
from the Oscillatoria.
Photosynthesis is carried
on readily by this plant, as
is evident from the oxygen
bubbles which it gives off
freely in sunlight.
Reproduction in Oscilla-
toria is usually performed
by the breaking off of fila-
ments at the places where
dead cells occur. Each sepa-
rated bit of filament continues to produce new cells by
the formation of new partition walls (Fig. 152). The
simple method of cell-division shown in the figure is not
A, a filament of Calothrix, reproducing
by hormogonia, h, segmented portions
which escape from the sheath of th&
filament ; B, Rivularia. (Both A and
B greatly magnified.)218
ESSENTIALS OF BOTANY
the usual one in higher plants. In the latter every cell
commonly possesses a distinct nucleus, and this generally
goes through complicated changes of form during the pro-
cess of nuclear division (see Bergen and
Davis’ Principles of Botany, Sect. 199).
277. Summary of the Blue-Green
Algae. — Many species of the blue-green
algae occur in fresh water, especially in
warm waters which are impure from
decaying organic matter, and in hot
springs, some are found in sea water, a
good many flourish on damp earth, and
a few inhabit cavities in other plants.
The blue-green algae are plants of
very low organization. Some of them
consist of single cells, living in a soli-
tary way, others have the individual
cells held together in masses by a
gelatinous substance, and still others,
still further. (Much like Oscillatoria, consist of thread-like
magnified.)	P ,,
rows oi cells.
Fig. 152. Oscillatoria.
A few cells are shown
treated with reagents
to show the protoplas-
mic cell-conteuts more
clearly. At b the cell-
wall is sending a par-
tition inward, and the
protoplasmic contents
beginning to divide.
At c the division (fis-
sion) has proceeded
Blue-green algse differ from other algte in the nature of
their coloring matter,1 in the absence of well-defined nuclei
in the cells, and in the simple mode of reproduction, by
cell-division. From the readiness with which their cells
split into new ones they are often called fission algce.
1 Their color is never exactly that of chlorophyll, but ranges from some-
thing not much unlike chlorophyll to blue-green, orange-yellow, brown, red,
or violet.THE ALG.E
219
SPIROGYRA, —ONE OF THE CONJUGATING ALG2E
278. Occurrence. — Spirogyra, one of the commonest of
the plants known as pond-scums, occurs widely distributed
throughout the country in ponds, springs, and clear, slow
streams. It is of a bright green
color (yellowish green when
producing spores). In warm
sunny weather the masses usu-
ally float, buoyed up by the
Fig. 153. A Group of Diatoms.
A, Achnanthes; B,Cocconema; C, Merld-
ion; D, Pleurosigma.
A, Micrasterias; B, B', Staurastrum
(two views); C, Closterium.
numerous oxygen bubbles which the plants set free. It
grows in unfrozen springs even in midwinter. Not in-
frequently several species are found growing with the
filaments intermixed.220
ESSENTIALS OF BOTANY
279.	Gross Structure. — Gently rub between the finger and thumb
a mass of filaments and note the feeling, unlike that of most fila-
mentous algae.
Tease out a few filaments in a very little water in a 'white saucer
and examine with the magnifying glass. Note:
(a) The color of the threads.
(i)	Their diameter.
(c)	Their length, relative to their diameter. Do they branch ?
280.	Minute Structure. — Mount some bright green filaments in
water under a large cover-glass, examine with m.p., and note :
(a) The form of the filaments, whether perfectly cylindrical or not.
([b) The division of each filament into many cells by transverse
partitions. Make a drawing to show these points.
Examine with h.p. and note :
(c)	The shape of a single cell.
(d)	The thickness and form of the cell-walls, both at the exterior
of the filament and in the partitions.
(e)	The cell-contents including:
(1)	Chlorophyll bands, or chromatophores. Count these.
(2)	Pyrenoids, or starch centers.
(3)	Clear cell-sap occupying most of the interior of the cell.
Take some Spirogyra which lias been for a good many hours in
bright sunlight. Mount a few filaments and slightly stain them by
running in iodine solution at one edge of the cover-glass while water is
withdrawn from the other edge by a bit of blotting paper. Examine
with h.p. and note :
(/) The pyrenoids, small light-colored spots in the chlorophyll
baud, each surrounded by many dark-stained starch granules.
(g) The nucleus, a lens-shaped or ellipsoidal body, usually stained
brown by the iodine, and often in a position near the center of
the cell.
Mount a few filaments of Spirogyra in water under a small cover-
glass, run in five-per-cent solution of common salt render one edge of
the cover, and watch the filaments through m.p. The h.p. may later
be substituted. Note the manner in which the living protoplasm of
the cell, the protoplast, shrinks away from the cell-wall. The denser
salt solution draws out water from the cell-sap at the interior of the
protoplast and thus causes the latter to shrink. The process is calledTHE ALG.E
221
plasmolysis. It is an excellent illustration of osmosis and is easily
demonstrated in many cells with thin walls and rather watery
protoplasts.
281. Sexual Reproduction of Spirogyra. — Cut ofi with the dissect-
ing scissors very small portions of material from the yellowish uneven
filaments of Spirogyra which are often found clinging together.
Fig. 155. Conjugating Filaments of Spirogyra.
(Considerably magnified.)
A, beginning of the process; B, the same filaments in a more advanced
stage of spore-formation. The cells at a in each portion of the
figure are at an earlier stage of conjugation than those at b.
n, nucleus; c. chloroplast.
Mount in a little water, without disturbing the relative position of
the filaments, and examine first with m.p., then with h.p. Xote:
(a) Filaments lying paired, as in Fig. 155, B, connected hy con-
jugating tubes.
(J) Filaments in which the tubes have not been fully formed but
appear only as projections (Fig. 155, .1, a).
(<•) The formation of ellipsoidal bodies, zygospores, by the union
of the protoplasts of two conjugating cells.
(</) Intermediate stages between cells in their ordinary condition
and cells containing a single zygospore or entirely emptied of their
contents.222
ESSENTIALS OF BOTANY
282. Discussion. — Spirogyra resembles Oscillatoria in
consisting of filaments composed of a row of cells each of
which is an individual plant. Its structure is, however,
of a much higher character since the chlorophyll-containing
material is in distinct bands, the pyrenoids form a special
starch-making apparatus, and
there is a well-defined nucleus.
Spirogyra has a sexual as well
as a non-sexual mode of repro-
duction, while in Oscillatoria
the reproduction is always non-
sexual.
Asexual reproduction, in
Spirogyra as in Oscillatoria, con-
sists of a process of cell-division,
shown in Fig. 156. The nu-
cleus divides into two daughter
nuclei, and the protoplast be-
comes divided into two portions.
A new partition-wall begins as a
sort of ring, or diaphragm, and
at length completely separates
the two new nuclei. The pro-
cess of cell-division in Spirogyra
is much more complicated than
in Oscillatoria, as in the former plant the nucleus goes
through a remarkable series of changes (mitosis)1 previous
to the formation of the daughter nuclei shown in Fig. 156.
Sexual reproduction consists in the union of two appar-
ently similar cells belonging usually to different filaments.
A sexual cell which unites its contents with those of
1 See Bergen and Davis’ Principles of Botany, Sect. 199.
Fig. 156. Process of Non-
Sexual Reproduction in a Spe-
cies of Spirogyra. (x 230.)
At n, n the daughter nuclei are
seen on either side of the newly
forming partition wall w. By
its growth the partition pushes
inward the band of chlorophyll
ch which lines the cell-wall.
Sections of this band are seen
at various points a-. Threads
<of protoplasm join it to the
nuclei.THE ALGrE
223
another cell in a reproductive process is called a gamete.
If the gametes are similar, the resulting spore is called a
zygospore. In the case of Spirogyra the zygospores are of
service to the species by tiding over the winter season, or,
in regions with a long, rainless summer, the dry season.
In cool climates they are formed during the summer, but
usually sink and remain long dormant, each throwing out
a new filament and forming a new colony in the spring.
283.	Summary of the Conjugating Algae. — These algae
all occur in fresh or merely brackish water. Every cell has
a nucleus. The chlorophyll is arranged in comparatively
large protoplasmic bodies, which often take the form of
spiral bands. The manner in which the zygospores are
formed from the union of non-motile cells in Spirogyra is
characteristic of the conjugating alga.
One family, that of the desmids (Fig. 154), is in some
respects similar to the preceding class (the diatoms, Fig.
153). Spirogyra and some other thread-like genera of the
conjugating algae much resemble the next class (the green
algae), though not the one shown in Fig. 157.
(EDOGONIUM, ONE OF THE GREEN ALG2E
284.	Occurrence. — (Edogonium is found in pools, quiet
ponds, horse-troughs, or slow streams of water throughout
the year. This filamentous alga grows attached to stones,
dead leaves, or other submerged objects.
285.	Gross Structure.1 — Examine with the magnifying glass a
small amount of the material in a little water, and note :
(a)	Whether the filaments are simple or branched.
(b)	Whether they are long or short.
(c)	Differences between the base and tip.
1 See Bergen and Davis’ Principles of Botany, Sect. 220.224
ESSENTIALS OF BOTANY
286.	Minute Structure. — Make a drawing of one or more filaments
as seen with l.p. Draw the basal and the apical cell as seen with h.p.
Under h.p. draw one of the cells near the middle of a filament
and note:
(«') The large cliromatophore, which almost fills the cell.
('b) The nucleus (if it can be seen).
(c) Pyrenoids. Test with iodine to see whether starch is present.
287.	Reproduction.
I.	Asexual
With h.p. look for cells in any of the filaments in which the proto-
plasmic body of the cell has changed into a pear-shaped cell (zoospore)
furnished at the smaller end with a fringe of cilia, or bristle-shaped
appendages. Look also for the pear-shaped zoospores swimming
freely about by means of their cilia. Study their movements, then
run in iodine under one edge of the cover-glass, to kill the cells, and
note the form and structure of the zoospore. Draw. If any germi-
nating zoospores can be found, draw them.
II.	Sexual
With h.p. look for filaments which have large swollen cells at
intervals along their length. Such a cell is called an oogonium and
contains one female gamete, or egg. Note :
(a)	The general form of the oogonium. Draw.
(b)	The pore or opening to allow of fertilization.
(c)	The egg-cell which nearly fills the oogonium.
Look for antlieridia, groups of rather flat, tabular cells occurring
near oogonia. These produce ciliated sperms, -which enter the egg-
cells and fertilize them. Draw a group of the disk-shaped cells.
Look for fertilized egg-cells, which may be distinguished by their
heavy cell-walls. This fertilized cell is an oospore. In the oospores
seen note :
(a)	The dense cell-contents, due to the accumulation of food
material. Test with iodine solution for starch.
(b)	In the older oospores the division of the contents into ciliated
zoospores, each of which may grow into a new filament of (Edogonium.
Draw oospores at various stages.THE ALG.E
225
288.	Discussion. — (Edogonium is a plant of decidedly
higher type than Spirogyra. While the nutrition of both
plants is much alike, (Edogonium shows a decided advance
over Spirogyra in the structure of the vegetative filaments,
inasmuch as these are not alike at both ends, but have a
definite cell which serves as a holdfast and a terminal cell
different from the others of the filament.
The sexual reproduction of (Edogonium is accomplished
bv the union of unlike gametes (sperm and egg-cell) and
is therefore higher in type than that of Spirogyra in which
the gametes appear to he alike. The small size of the
sperms enables them to accomplish the fertilization of
the egg with the expenditure of only a trifling amount
of material, and the motility of the sperms enables them to
reach the egg quickly, instead of drifting against it as one
filament of Spirogyra drifts against another. Economy and
certainty in the process of sexual reproduction are features
of the progress of plants from lower to higher forms.
In some species of (Edogonium the antheridia are pro-
duced on small short filaments called dwarf males. These
are developed from zoospores which attach themselves to
the female filament or to the oogonium.
YAUCIIERIA, ONE OF THE GREEN ALG.E
289.	Occurrence. — Vauelieria, or green felt, is one of
the rather widely distributed green algae, some species
being found in salt water and others in stagnant fresh
water, sometimes in fresh running water or on damp soil.
V. sessilis, the commonest species, occurs covering the
earth of pots in greenhouses. When growing on earth it
is rather easily recognized by its dark green color and the226
ESSENTIALS OF BOTANY
felt-like masses which it forms. It must not be confused
with moss protonema (Fig. 199) which also grows on
damp earth. The protonema has many cross-partitions in
the filaments (often oblique in position) and lacks other
Fig. 157. Vaucheria synanclra.
A, a filament with archegonia and antheridia (considerably magni-
fied) ; B, part of same much more highly magnified; o, oogonium;
a, antheridium; (\ a later stage of B; I), end of a filament with
a zoospore, z, escaping (highly magnified).
characteristics shown in Fig. 157, A. It will also usually
be found to be developing young moss plants.
290. Gross Structure. — Place in a white saucer or a watch glass
with very little water some hits of earth on which Vaucheria is grow-
ing. Have other specimens growing in water in a sunny place,
where they should have remained undisturbed for a week or more,THE ALGHD
227
covered with a bell-glass. Examine specimens on earth and in water
with a magnifying glass and note :
(a)	The general appearance of the felted mass of plants.
(b)	The position of the growing filaments with reference to light.
This is to be looked for only in specimens left long undisturbed in
a good light.
(r) The mode of branching.
(cl) The rhizoids or root-like extensions of filaments into the earth.
These are best shown by washing away the earth with a carefully
managed stream of water from a wash bottle.
291.	Minute Structure. — Mount in water some filaments that have
grown many days in water, examine with m.p., then with h.p.,and note:
(а)	Their varying diameter and the details of the branching.
(б)	The presence or absence of cross-partitions.
(c)	The form and size of the chlorophyll bodies.
If stained preparations mounted in balsam are available, study
them with h.p. and note :
(d)	The very numerous nuclei. Make drawings to show the
points (a), (b), and (c).
292.	Reproduction.
I.	Asexuai,
"With m.p. examine plants that have been growing in water in a
sunny place for a week or more.1 Look for:
(a)	The formation of transverse partitions near the tips of
branches. The end of the branch thus becomes a spore-case.
(b)	The formation in each spore-case of a roundish, ciliated com-
pound zoospore.
(c)	Zoospores escaping or swimming about among the filaments.
(id) Zoospores beginning to grow into new plants.
>
II.	Sexual
In the same kind of material studied in I, look for paired, unlike
organs occurring on the sides of some filaments (Fig. 157, B, C). Kote:
(a) The shape, size, and structure of the smaller organ. It is an
antheridium, producing very minute, ciliated sperms.
1 For culture directions to secure fruiting Vaucheria and zoospores see
Bergen and Davis’ Field and Laboratory Manual, pp. 95, 211, 212.228
ESSENTIALS OF BOTANY
(ft) The shape and size of the larger organ. It is an oogonium,
containing many nuclei. Within the oogonium is developed an egg,
which after fertilization becomes an oospore.
(c) The shape, size, and thick cell-walls of the mature oospores.
293. Discussion. — Vaucheria differs greatly from Spiro-
gyra and from most of the green algae. The filaments are
not composed of separate cells, but the long branching tube
is a complex cell with many nuclei. The spore-cases of
the zoospores, the antheridia, and the archegonia are of
course additional cells or cell groups growing from the
filament.
The process of sexual reproduction in Vaucheria consists
of the union of the protoplasm of a sperm with that of an
egg. This union is quickly followed by the development
of a heavy cell-wall about the fertilized egg. The oospore
thus formed can resist unfavorable conditions much longer
than the mature plants could do so. After a resting period
the spore germinates and produces a new individual.
Vaucheria belongs to a considerably higher stage of de-
velopment in the plant world than Spirogyra does. This
is shown especially by two important points of difference.1
1.	Vaucheria has one kind of cell for doing the vegeta-
tive work of the plant (photosynthesis, etc.) and other kinds
for reproduction. In Spirogyra all the cells appear alike.
2.	In Vaucheria the gametes are unlike. The sperms
and the eggs are not only very unequal in size, but they
differ much in structure and in power of movement, the
sperms being freely motile while the eggs are stationary.
In Spirogyra any gamete appears to be like all the others.
1 These have already been stated in Sect. 288, but as (Edoqonium is more
likely to be omitted from a brief course than Vaucheria it seems best to repeat
the statement.THE ALGiE
229
Specialization of the apparatus for reproduction and differ-
entiation of gametes are always found to accompany progress
from the lower to the higher stages of plant development.
Fig. 158. End of a Main Shoot
of a Stonewort, Chara.
(About natural size.)
294. Summary of the Green
Algae. — Green algae occur
almost all over the earth's sur-
face. They reach their highest
development in fresh water, but
there are many marine genera
and species, and one of the most
conspicuous of all the groups
is that which embraces the sea-
lettuce (TJlva) and its allies.
Fig. 159. Part of a “ Leaf ’ ’ of Fig. 158.
(Considerably magnified.)
a, antheridium; v, oogonium. At the
right are a young antheridium and
archegonium.
This plant is a familiar object, waving as it does from
rocks, piles, and wharves alongshore. Terrestrial genera
and species of green algse are not uncommon.230
ESSENTIALS OF BOTANY
Under the class green alga?. are grouped plants of many
degrees of complexity in their organization and mode
of reproduction. Complex cells like that of Vaucheria
are not uncommon, and other genera have cell
colonies of net-like form or take on thread-like
shapes, like (Edogonium, or leaf-like or disk-like
shapes, like the sea-lettuce or like Coleochcete
(Fig. 220).
Highest in structure of all the green alga; are
the stoneworts (Figs. 158, 159).
In green alga? the chlorophyll is not disguised
by the presence of other coloring material. Re-
production is of many kinds, — often, as in
Pleurococcus, wholly asexual, sometimes sexual,
by the fusion of like gametes, and sometimes,
as in (Edogonium and Vaucheria, sexual by
the fusion of unlike gametes.
FUCUS, ONE OF THE BROWN ALG.E
295. Occurrence. — Fucus vesiculosus,
or bladder wrack, one of the commonest
of the so-called rockweeds, is found grow-
ing usually on rocks between high- and
low-water marks, along the northern coasts
of both hemispheres. It is often very
luxuriant, completely covering the sur-
face of the rocks to which it clings; and is extremely
tough, resisting the most violent beating of the waves. It
is easily recognized by the ribbon-like form (Fig. 161) with
frequent branching and the numerous air-bladders which,
buoy it up in the water.
Fig. 160. A Kelp
(Laminaria), one
of the Brown
Algie. (Much
reduced.)THE ALG-E
231
296.	Gross Structure. — Examine some fresh or preserved material
and note:
(a) The size, shape, and texture of single plants, the mode of
branching, and the slimy coating of the
entire plant.
(i) The location of the air-bladders.
(c) The mode in which the plant is
attached to the rock by an expanded
holdfast.
(tf) The enlarged fruiting tips, or re-
ceptacles, of some branches. Draw. The
growing point is in a pit at the tip of
each branch.
297.	Reproduction. — Study the recep-
tacles of different plants, cutting some
of them across, and note that there are
two kinds, differing in shape and in the
external color and color of the contents.
With a two-inch objective or a magnifying
glass sketch a cross-section of each kind of
receptacle showing the distribution of the
conceptacles (Fig. 164), each opening by a
pore to discharge its contents.
Pick out with the point of a scalpel the
contents of a conceptacle of each kind and
examine with m.p. Note:
(а)	The sterile hairs.
(б)	The sac-shaped anlheridia borne on
branching hairs (Fig. 162).
(c) The nearly spherical oSgonia, large
cells from each of which eight eggs are
developed.1
Observe that while the conceptacle
shown in Fig. 164 contains both antheridia
and oogonia, those of Fucus vesiculosus contain only one kind of
sex organ.
1 Prepared slides with stained sections of conceptacles may be studied to
advantage.
Fig. 161. Part of Thallus
of a Rockweed (Fucus
platy carpus). (Natural
size.)
The two uppermost branch-
lets are fertile.232
ESSENTIALS OF BOTANY
298. Discussion. — Fucus is a much more
highly developed plant than any of the blue-
green or green algae studied in the previous
sections. It has a complete cellular
structure and there is considerable
division of labor among the differ-
ent parts of the plant. It has a
special holdfast, air-bladders to
serve as floats,1 a tough midrib run-
ning lengthwise of the branches and
strengthening them, and expanded
margins of the
blanches, afford-
ing ample
Fig. 162. Rockweed
(Fucus)
A, antkeridia borne on branch-
ing hairs (x 160); B, three
sperms from the same
(X 330).
surface for
photosyn-
thetic work.
The outer layers of cells are espe-
cially devoted to photosynthesis
and the inner ones to storage of
food material. The
brown cell-contents
contained in Fucus
and other brown algae
is highly efficient in
photosynthesis.
There is no asexual
process of reproduc-
tion in Fucus. Sexual
reproduction is ac-
complished by the eggs and sperms becoming forced out
Rockweed (Fucus).
A, oogonium, its contents dividing into eight
oospheres (X 160); B, an oospliere, escaped,
surrounded by many sperms (X 160).
1 These are absent in some species (Fig. 161).THE ALGiE
233
of the conceptacles when the plants which hear them
become partially dry between tides. When the plants
are again covered with sea-water, each egg becomes sur-
rounded by actively swimming sperms which set the egg
itself in motion
(Fig. 163, B). The
egg is soon fertil-
ized, becomes an
oospore surrounded
by a special cell-
wall, germinates,
and forms a new
plant. The unlike-
ness of the male
and female gametes
of Fucus in form,
size, and motile
power is very great;
tens of thousands
of sperms would
be needed to make
up a bulk equal to
that of a single egg.
299. Summary
of the Brown Algae.
■ The brown algae
Fig. 16t. Transverse Section of Conceptacie of a
Rockweed (Fucus platycarpus). (x about 35.)
aie practically all	7i, hairs; u, antheridia; o, oogonia.
of them marine,
abounding most in the northern seas, and are usually
known as seaweeds. They vary greatly in size, some being
almost microscopic, while others, like the giant kelps of
the Pacific, reach a length of from six hundred to nearly234
ESSENTIALS OF BOTANY
a thousand feet. The structure of some of the smaller
forms is not very unlike that of the pond-scums (Sect. 278),
while that of the larger ones, as the rockweeds, Fucus
(Sects. 295, 296), and the kelps is rather complicated. The
gulf-weed, Sargassum, related to the rockweeds, has ex-
panded leaf-like branches for photosynthesis, globular air-
bladders to float the plant, and small branches specialized
for reproduction.
In the brown algae the coloring matter appears yellowish
brown or dark brown; by washing the plants in fresh
water they soon become green, as the brown pigment is
dissolved and removed. The reproduction is of various
types, in the kelps wholly asexual, and in Fucus and its
allies wholly sexual (Sect. 298).
RED ALGJE 1
300.	Occurrence. — The red algae are mostly marine and
many of them are familiarly known as sea-mosses. They
are especially abundant in the warmer seas, and some of
them flourish in deeper waters than are frecpiented by the
brown algae.
301.	Form and Structure. — Most of the red algae are of
moderate size, but some genera are minute, almost micro-
scopic. The simplest forms consist of delicate branching
threads, each composed of a single row of cells. Others,
like the so-called Irish moss, appear as rather stout branch-
ing thalli, and others form broad wavy sheets. Some occur
as incrustations on rocks or coral. The delicate feathery
1 No laboratory studies on this group are given since the vegetative char-
acters are not important for study in a brief course, and the sexual reproduc-
tion is too complicated to be mastered by beginners in botany.THE ALGiE
235
kinds are the most beautiful of all the marine species. The
colors of red algae vary in dif-
ferent genera all the way from
bright red to dark purple or
reddish brown ; one fresh-water
genus, Batrachospermum (Figs.
165, 166), is often greenish.
302. Reproduction in Red
Algae.— Sexual reproduction
among these algae is highly com-
plicated. It may be briefly
described as due to the action
of peculiar non-motile sperms
upon the egg contained in a
flask-shaped cell provided with
a hair-like extension on which
the sperms become lodged.
Asexual reproduction is frequently accomplished by the
formation of spores produced
in fours and known as tetra-
spores (Fig. 168, B).
303. Additional Notes on the
Algae. — The algae embrace
so many types of plant life, in-
cluding in all at least twelve
thousand species, that it is not
easy to make general state-
ments which will apply to all
the groups. The number of
species may be more easily
understood when it is mentioned that a single genus of
diatoms contains some nine hundred species, and a genus
Fig. 166. Part of a Filament
of Batrachospermum, not the
species 'of Fig. 165. (Highly
magnified.)
Fig. 165. Batrachospermum, a
Red Alga. (Slightly magni-
fied.)236
ESSENTIALS OF BOTANY
of desmids three hundred. The number of individuals is
inconceivably great. For example, there are in various
Fig. 167. Polysiphonia, a Bed Alga.
A, a considerable portion of a female plant about natural size; B, a small
bit of a male plant much magnified, showing the antherhlia, or sperm-
producing organs, a; C, a minute portion of a female plant (.i), showing
clustered carpospores enclosed in an urn-shaped enveloi>e.
parts of the United States, in Africa, in Bohemia, and else-
where extensive beds of siliceous shells or cases of fossil
diatoms, often from thirty to fifty feet thick, and sometimesTHE ALG2E
237
many miles in extent. It has been estimated that the
diatomaceous earth of the Bohemian deposits contains
forty-one million diatoms in every cubic inch. Similar
deposits are to-day being formed in swamps, in lake-beds,
and over large areas of sea-bottom.
The conditions of life under which
algae can exist are extremely various.
One unicellular species, the red snow
plant, Splioerella nivalis, gives a pink
color to many square miles of snow in
the arctic regions. Some of the blue-
green algae, on the other hand, live in
hot springs at a temperature of 145°
Fahrenheit. It is usually stated that
algae differ from fungi in being ‘self-
supporting, but at least one parasitic
species is known.
The green algae have a special inter-
est for the scientific botanist from the
fact that they are supposed to be the
ancestors of the mosses.
Few algae have much direct eco-
nomic value as articles of human food
or as sources of manufactured prod-
ucts. Some, as the “ Irish moss,'" the
dulse, and “ Ceylon moss,” are eaten.
Rockweeds are considerably used as fertilizers. Diatoma-
ceous earth is sold under various names for polishing silver
and other metals. Algae, particularly of some minute float-
ing marine groups, are of the greatest importance as food
for shellfish and for many of the small organisms which
form the diet of fishes.
Tig. ICS. Red Algse.
A, spores of Xemalion
(greatly magnified);
B, portion of thallus of
a red alga. Lejolisia,
with tetraspores, t.238
ESSENTIALS OF BOTANY
The occurrence of blue-green and green algte in city
water-supplies is often a matter of serious importance, as
it may give rise to very disagreeable tastes and smells.
Some of the odors have been described as the moldy, the
fishy, the “ pig-pen ” odor, and so on. Various means have
been adopted for getting rid of the organisms, and most
of them (including some animalcules) may readily be de-
stroyed by adding a small proportion of copper sulphate
to the water in the reservoir.1 A bag of the copper salt
trailed behind a boat rowed about over the surface will
readily supply the needed amount of sulphate. Some of
the most objectionable organisms are killed by as small a
proportion of copper sulphate as one pound to five or ten
million pounds of water, and in such a dilute solution as
this the salt is not capable of exerting any poisonous
action upon the drinkers of the water.
1 See Bergen and Davis’ Principles of Botany, pp. 170, 171. See also
Whipple’s Microscopy of Drinking Water, Chapter IX, John Wiley & Sons,
New York.CHAPTER XXY
THE FUNGI
304.	Definition ; Occurrence. — The fungi are ’parasitic
or saprophytic spore-plants. They constitute a series of
the division Thallophyta. The difference between algae
and fungi is one of mode of life, not of structure or of
reproductive methods; and it cannot be said that fungi as
a whole are either higher or lower in the scheme of classi-
fication than algae.
Fungi occur in all situations where they can find organic
food on which to live. Some are terrestrial, others aquatic;
some can support life in a variety of situations, others are
confined to the interior or exterior of the body of a single
kind of host.
305.	Classes of Fungi. — In treating the fungi they will
here be grouped under five classes as follows :1
Class	7.	Bacteria, Schizomycetes.
“	8.	Yeast fungi, Saccharomycetes.
“	9.	Algal fungi, Phycomycetes.
“	10.	Sac fungi, Ascomycetes.
“	11.	Basidia fungi, Basidiomycetes.
The classification of this great group of spore-plants
is based partly on the modes of reproduction, partly on
other considerations, and is as yet far from being definitely
settled. The life history of many is only partially known.
1 See p. 210.
239240
ESSENTIALS OF BOTANY
306.	Occurrence. — Bacteria are to be found almost
everywhere. Although their extremely small size makes
them quite invisible without the microscope, they are
present in unimaginable numbers in most of the air we
breathe and much of the food that we eat and the water
that we drink. The commoner kinds are saprophytic and
are to be found on most kinds of fermenting or decaying
organic matter. Parasitic bacteria of many species occur
in the bodies of animals and plants.
307.	Cultures of Bacteria. — It is much easier to observe some of
the effects produced by the growth of bacteria than to study the in-
dividual organisms. These are so small that in order to make out
the details of their structure one needs a more powerful microscope
than is usually found in school laboratories.
Pure cultures of bacteria are commonly made in some preparation
of gelatine in sterilized test-tubes. Boiled potatoes serve a good pur-
pose for simple (but usually not pure) cultures.
Select a few small roundish potatoes with skins entire and boil
in water for a sufficient time to cook them through. Cut them in
halves with a knife well scalded, or sterilized, i.e., freed from all liv-
ing organisms, in a flame, and lay each, with cut surface up, on a
saucer, covering each with a glass tumbler. The tumblers and
saucers should be well scalded or kept in boiling water for half an
hour and used without wiping. Sterilization may be improved by
baking them in an oven for an hour.
308.	Inoculation. — The culture media prepared as above may
now be inoculated. Uncover them only when necessary and quickly
replace the cover. Scrape a little material from the teeth, tongue,
kitchen sink, floor of the house or schoolroom, or any other place
you may desire to investigate. With the point of a knife blade or a
needle sterilized in a flame, inoculate a particle of the material to be
cultivated into the surface of one of the potatoes. Several cultures
may be made in this way and one or more left uninoculated as
checks. Another may be left uncovered in the air for half an hour.
Others may be made with uncovered potatoes. Number each cul-
ture and keep a numbered record.THE FUNGI
241
Keep watch of the cultures, looking at them daily or oftener. As
soon as any change is noticed on the surface of a culture, make a
descriptive note of it and continue to record the changes which are
seen. .Note the color of the areas of growth, their size, outline, ele-
vation above the surface, and any indications of wateriness. Any
growth showing peculiar colors or other character of special interest
may be inoculated into freshly prepared culture media, using any
additional precautions that are practicable to guard against con-
tamination.
309.	Microscopic Examination. — Examine with h.p. some of the
cultures. Place a particle of the growth on a slide, dilute it with a
drop of clear water, and place a cover-glass over it. Note the forms
and movements, also the sizes if practicable, of any bacteria that are
found. Examine also scrapings from the surface of the teeth and
look for various forms of bacteria.
310.	Minute Structure. — Bacteria are spherical, rod-
like, or spiral cells (Fig. 169). The cell-wall is thin and
the protoplasmic contents usually colorless and apparently
destitute of a nucleus. They are the smallest and among
the simplest of known organisms. Extremely delicate
cilia are often found, either at one extremity of the cell
or distributed over its general surface. The movements
of bacteria are due to the lashing motion of the cilia.
311.	Life Habits of Bacteria. — As already stated (Sect.
306), bacteria are either saprophytic or parasitic. Species
of the latter group can often be artificially induced to live
as saprophytes.
Some kinds can only exist in the presence of free oxygen,
while others cannot live in its presence. Those which
require oxygen are more common and they flourish upon
the surface of decaying animal and vegetable substances,
causing them to putrefy. If meat, milk, eggs, or other per-
ishable substances are sterilized by heating and then placed
in sterilized vessels so arranged as to prevent any contact of242
ESSENTIALS OF BOTANY
the contents with air containing living bacteria, no putre-
faction can occur. Canned goods may be kept unspoiled
for an indefinite number of years, not because all the
Fig. 100. Bacteria stained to show Cilia.
A, Bacillus subtilis, found in hay infusions; B, Spirillum undula, found
in water containing decaying fish, algse, etc.; C, species of Pseudomo-
nas; D, Planococcus citreus, which forms yellow patches on various
substances; E, Bacillus typhi, the cause of typhoid fever; F, Micro-
spira comma, the cause of Asiatic cholera.
air has been driven out of the cans, hut because they and
everything in them has been sterilized by heat. Bacteria
in the active growing condition cannot live if exposedTHE FUNGI
243
for an hour to a temperature of 149°-160° Fahrenheit
(65°-71°C.). The spores resist a much greater heat.
Light is unfavorable to the growth of bacteria in gen-
eral, and this is one important reason why living rooms
should be open to the sunshine.
Dryness will not immediately kill bacteria, but it stops
their growth, and it is for this reason that evaporated fruits
and vegetables keep without decaying. In the case of
salted meats and fish, either smoked or not, the dryness
and the presence of
much salt prevent decay.
Smoking adds some ere-
osote which is an addi- a' %
tional safeguard. Most	6	vVvti};
bacteria cannot grow in
the presence of much
sugar or of vinegar, and	" '"’.s'-y/bfvvF'"
this accorrnts for the
keeping qualities of rich
preserves and jellies as
well as of pickles.
312. Reproduction.—
Bacteria under ordinary
circumstances reproduce by the division of the cells, each
parent cell forming two new ones. From this fact they
are often called fission fungi. Fission goes on much faster
at rather high temperatures (Fig. 170). Resting spores
are formed by many species. The process of spore forma-
tion consists of the interior portion of the protoplasm
collecting into a minute ellipsoidal or globular mass which
becomes surrounded by a thick membrane. The spores
can survive high temperatures and extreme dryness, so
Fig. 170. Effect of Variations in Tem-
perature on Bacteria Growth.
a, a single bacterium; 6, its progeny in
twenty-four hours at 50° Fahrenheit;
c, its progeny in twenty-four hours at
70° Fahrenheit.244
ESSENTIALS OF BOTANY
that they are able to continue the life of the species on
through very unfavorable conditions.
313. Economic Importance. — The great importance of
the bacteria in relation to many of the affairs of everyday
life has been suggested in several of the preceding sections.
Farming, butter and cheese making, canning fruits and
vegetables, and a variety of other manufacturing opera-
tions are largely dependent on employing certain useful
bacteria or on warding off the attacks of injurious species.
Such important diseases as influenza, consumption, ty-
phoid fever, diphtheria, cholera, and the plague are caused
by the attacks of parasitic bacteria, and a most important
division of medical science is occupied with the detection
of these parasites and the means of destroying them.1
YEAST FUNGI
314.	Occurrence. — Yeasts are microscopic one-celled
plants which are very widely distributed in the air and in
the soil. On account of their minute size their presence
is generally recognized only by the effects which their
growth produces. Beer yeast is used in bread making and
in fermenting various gruel-like preparations of ground
malt, rye meal, corn meal, and so on in the manufacture of
beer and many distilled liquors. This species of yeast is
only known in a cultivated condition, but there are many
wild yeasts which cause the fermentation of grape juice,
cider, and canned fruits.
315.	Minute Structure and Reproduction. — The student
can gather from Fig. 171 something of the structure of
1 For general information about bacteria read Conn’s Bacteria, Yeasts, and
Molds in the Home, Ginn & Company.TITE FUNGI
245
the yeast-cell. It is spherical or ellipsoidal in shape, thin-
walled, and contains nearly colorless protoplasm, which in-
cludes oily droplets known as vacuoles and a well-defined
nucleus.
Multiplication ordinarily takes place by a process of bud-
ding by which the nucleus divides and a new cell is pushed
out from the old
one and finally cut
off from it by a new
cell-wall (Fig. 171).
Spore formation
occurs when yeast is
grown with scanty
nourishment. The
protoplasm breaks
up into small, nearly
spherical masses,
often two or four in
number, and these
form spores which re-
sist unfavorable con-
ditions better than
the ordinary yeast-
cell.
316. Alcoholic Fermentation. — The growth of yeast in
a liquid which contains sugar destroys part or all of the
sugar, changing it mostly into alcohol and carbon dioxide.
The alcohol remains mixed with the liquid, while most of
the carbon dioxide escapes in little bubbles.
In bread making the yeast grows at the expense of sugar
in the dough (derived from the flour). The bread rises as
the bubbles of gas escape, at the ordinary temperature, and
Common Yeast very Highly
Magnified.
a and b show vacuoles; c shows a nucleus n inside
of the yeast-cell; cl shows a budding cell with
the nucleus dividing; e shows the cell divided,
the new cell containing a bit of the old nucleus.246
ESSENTIALS OF BOTANY
becomes still lighter as the gas expands in the oven. Cakes
of compressed yeast are nowadays generally used in bread
making. It is important that they should he as fresh as
possible, since when they are old they are likely to contain
some wild yeasts and many bacteria. These are pretty sure
to injure the quality of the bread made from such yeast.
RHIZOPUS, ONE OF THE ALGAL FUNGI
317.	Occurrence.—The common bread-mold, Rhizopus
nigricans, is found upon bread or cake left in a warm
damp place, or on sweet potatoes, squashes, or bananas.
Its spores are likely to be present in the dust of houses,
and many lie dormant for months, producing when they
alight on favorable food material a luxuriant crop of the
downy coating of white silky threads so familiar to all.
318.	Gross Structure. — Place some bread1 in a soup plate, wet
thoroughly, cover with a bell-glass, and leave for some days in a dark
warm place, renewing the water if necessary. When a considerable
growth of mold has appeared, examiue with the mag-nifying glass an
undisturbed portion as it grows from the surface of the bread. Note :
(a)	The tangled network, or mycelium, visible on the surface of
the bread (and really extending a good way down into it).
(b)	The size and appearance of the separate threads, or hyphcc, of
which the mycelium is composed.
(c)	The presence of certain erect aerial hyphse bearing minute
globular spore-cases at their tips. Describe the color of the youngest
spore-cases and that of the largest and oldest ones.
319.	Minute Structure. — Wet a little of the mold with alcohol (to
remove the air from it) and then mount in water and examine with
m.p. Note:
(a) The mode of growth of the hyphse, whether branched or
unbranched.
1 Gluten bread is particularly adapted for this culture.THE FUNGI
247
(&) The root-like branches, or rhizoids, which proceed from some
hyphse into the bread or other substratum.
(c) The presence or absence of transverse partitions in the liyphie.
Fig. 172. Unicellular Mycelium of a Mold (Mucor Mucedo), sprung
from a Single Spore.
a, b, and c, branches for the production of spore-cases, showing various
stages of maturity. (Considerably magnified.)
(d) The granular protoplasm, more abundant in some parts of
the hypliEe than in others.
Make one or more drawings to show the points above mentioned
(a-d).
320. Reproduction. — With h.p. examine a series of spore-cases of
various sizes and note :
(a)	The various stages in the development of the spore-cases.
(b)	The ripe spores escaping. Make a drawing to show these.
Sow some of the spores of (i) on the surface of “hay tea” made
by boiling a handful of hay in just wrnter enough to cover it and
then straining through cloth or filtering through a paper filter.248
ESSENTIALS OF BOTANY
After from three to six hours examine a drop from the surface of
the liquid with m.p. After about twenty-four hours examine another
portion of the mold from the
surface of the liquid. Note :
(c) The beginning of for-
mation of hvphfe and their con-
tinued development. Draw.
In a prepared slide study
the conjugation of mold hy-
pliae and the formation of
zygospores (Fig. 173).
321. Discussion. — The
bread-mold is a typical
saprophytic fungus. In
its structure, consisting
of a much-branched and
extremely large continu-
ous protoplast with many
nuclei, it considerably
resembles Vaucheria. Its
reproduction is of two
kinds, — asexual, by the
formation of spores within
a spore-case, and sexual,
by the conjugation of
similar-appearing threads
(gametes) forming zygo-
spores. These (Fig. 173)
are not as frequently pro-
duced by the bread-mold
as by some other closely related genera.
The formation of the asexual spores in spore-cases is
similar to the mode already mentioned in yeast fungi
Fig. 173. Formation of Zygospores
in a Mold (Mucor Mucedo).
1, threads in contact previous to conjuga-
tion; 2, cutting off of the conjugating
cells a from the threads b; 3, a later
stage of the process; 4, ripe zygospore;
5, germination of a zygospore and
formation of a spore-case. (1-4 magni-
fied 225 diameters; 5, magnified about
CO diameters.)THE FUNGI
249
(Sect. 315). The zygospore formation of bread-mold consid-
erably resembles tbe mode of spore production in Spirogyra
(Sect. 282), but tbe mold gametes contain many nuclei.
Fig. 174. Spore-Formation in Potato-Blight (Phytophthora
infestans), one of the algal fungi.
A, a well-developed group of stalks, proceeding from a mass of mycelium
inside the leaf and escaping through a stoma; B, a young, unbranched
stalk, h, hyphse of mycelium; o, stoma; $, spore. (Both figures
greatly magnified, B more than ^4.)
It appears highly probable that such algal fungi as
Rhizopus are degenerate descendants of green algee more
or less resembling Vaucheria.250
ESSENTIALS OF BOTANY
MICROSPHiERA, A SAC FUNGUS
322.	Occurrence. — Species of the lilac mildew, Micro-
sphcera Aim and allied forms, occur during the summer
and autumn on leaves of various herbaceous and woody
plants. The growth is confined to the surface of the leaf.
Among the commonest species are those which grow upon
lilac, oak, grape, cherry, willorv, and wild plants of the
Composite family. Some species are known to occur on
only one hoshplant, others on several, and the hosts may
belong to more than one family. Besides Microsphcera
there are about five other genera. All these fungi, from
the appearance which they present in their earlier stages,
are called powdery mildews.
323.	Gross Structure.1—Examine with the magnifying glass the
upper surface of a lilac leaf infected with M. Alni. Note:
(a) The color and distribution of the fungus on the upper surface
of the leaf.
(5) The powdery or moldy appearance of the leaves first gathered,
due to the abundant conidia (or con'idiospores).
(c) The yellow or black dots on late-gathered leaves, sac fruits.
324.	Minute Structure.2 —
I. The Mycelium.
Examine with h.p. some scrapings or thin sections parallel to the
leaf surface, or fungus spots from a leaf gathered early in the sum-
mer. Dried leaves may be moistened with five-per-cent solution of
1	Material for all the studies of this Microsphmra should he gathered at
three periods, — when the lilac leaves first begin to appear powdery (in June
or July), then in early September, and finally just before the fall of the leaves.
They should he pressed between sheets of porous paper.
2	If the teacher prefers to use material which will show larger sac fruits he
may use fresh or dried fructifications of the morel (Fig. 176). Dried morels
must be soaked in warm water before sectioning. The sections should be cut
perpendicular to the surface of one of the hollows of the morel.THE FUNGI
251
potassium hydrate some time before they are to be examined. In
the mycelial threads note :
(a)	The color (if any).
(b)	The mode of branching.
(c)	The presence or absence of cross-partitions. Draw.
II. Conidia.
Examine with h.p. a slide prepared as in I, and note:
(a) The size, shape, and color of the conidia.
(i) The manner in which the conidia-bearing branches are
Fig. 175. A Colony of Aspergillus, a Sac Fungus, one of the Com-
mon Molds, showing Mycelium and Spore-Clusters. The lower
figures show in detail the method of spore formation.
attached to the mycelial threads and the way in which the conidia
are cut off at the ends of these branches by cross-partitions.1 Draw.
III. The Sac Fruits.
Prepare slides from the material gathered at the end of summer
and at the fall of the leaf. Examine the yellowish or black sac
fruits with h.p. and note :
(a) The shape of the fruits.
1 It may be easier to demonstrate rows of conidia in “blue mold ” (Peni-
dllium) moistened in alcohol and then mounted in water.252
ESSENTIALS OF BOTANY
(6) The surface markings.
(c) The number, shape, and mode of branching of the appendages.
Draw a sac fruit showing the points above mentioned (a — c).
IV. The Spore-Sacs and Spores.
fruits under a very small cover-glass
and press the latter strongly against
the slide with a scalpel handle or the
square end of a lead pencil until some
sac fruits are crushed. Examine with
h.p. and note:
(a)	The spore-sacs (a.?ci) escaping
from the spore fruits.
(b)	The spores contained in the
spore-sacs. Make a drawing to show
the asci escaping from the spore fruit,
and the number, shape, and size of
the spores within the ascus.
325. Reproduction. — Micro-
sphcera is reproduced in two
ways. One method is asexual,
by means of abundant aerial
spores known as conidia, formed
by the subdivision of special
hyphre into short segments,
each of which may grow into a
new plant. The other method
is sexual, by the union of un-
Iig. 170. I he Morel (Morchella equal gametes to form a sac
esculenta). (Natural size.) .	. , ,
J fruit1 (developed somewhat like
that of the red algre) which contains many spore-sacs.
326. Discussion. — The sac fungi are of interest to those
who are not specialists in the study of this group, mainly
1 Iii most sac fungi it is very difficult to find the gametes; therefore no
laboratory work on them is here given.
Mount in water a few sacTHE FUNGI
253
on account of their economic importance. Forms differ-
ing enormously in general appearance, size, and life habits
are included in this class.
Here belong two genera of large, edible fungi, the morel
(Figs. 176, 177) and the truffle. Many injurious genera
are found, some of them saprophytes
and others parasites. Best known
among the former are the green and
the yellow molds, more properly
called mildews (Fig. 175). A few ex-
amples of the latter are the grape-
vine mildew, the black-knot fungus of
plum and cherry trees, the peach-curl
fungus, the bitter rot of apples, the
brown rot of peaches, and the plum
pocket fungus.
LICHENS, SAC FUNGI AS MESS-
MATES AYITII A LG IE
327. Definition, Occurrence.
— Lichens (Figs. 178,179) were
formerly supposed to be a dis-
tinct class of plants, and it is less
than forty years since their real
nature began to be understood.
-1 lichen is a combination of two
plants. The green cells, called the gonidia (Fig. 180, </), be-
long to some species of alga, and the remainder, the larger
portion of the growth, is a fungus (usually a sac fungus)
parasitic upon that alga. The groups of lichens correspond
in structure to certain groups of fungi, but the genera are
Fig. 177. A Vertical Section of
the Spore-Bearing Surface of
Fig. 176. (x 240.)
u, asci, or spore-sacs; m, myce-
lium ; p, pciraphyses, or sterile
filaments.254
ESSENTIALS OF BOTANY
sufficiently distinct so that lichens are best considered
by themselves for purposes of study and classification.
The relation of the fungus and its
algal host is not that of destructive'
parasitism, but rather a mutual rela-
tion (symbiosis) in which both fungus
and alga may have a vigorous growth.
The relationship has been investi-
gated in various ways, and it has been
found that, while the alga may thrive
FI(.. i78. a Lichen independent of the fungus, the ger-
(Xanthoria). (Natural minating fungus spores can grow only
Slze,')	to a limited extent if deprived of the
algal host; but if supplied naturally or artificially with
the proper alga they make a
normal growth. The same
alga may serve as gonidia to
a number of lichens, often
of very different form, and
while the number of lichens
reaches into the thousands,
the number of algfe known
to serve as gonidia is quite
small.
Lichens are widely distrib-
uted in all zones but flourish
particularly in northern re-
gions where other vegetation
is scanty. Some were for-
merly important as sources
of dyes. “ Iceland moss ” is a lichen used for food, and
a finely branching form, growing in extensive mats on
Fig. 179. A Lichen (Usnea).
(Natural size.)THE FUNGI
255
the soil, serves as food for the reindeer and is known
as “ reindeer moss.”
Most lichens grow
on the bark of trees,
on rocks, or soil
where they have lit-
tle moisture except
during rainfall, but
some grow where
they are constantly
wet. Some of the
latter are gelati-
nous. Most of the
■conspicuous lichens
are foliaceous or else
have a thallus com-
posed of branching,
cylindrical, thread-
like portions. But
many species, often Fig. 180. Transverse Section through Thallus
less conspicuous, are of a Lichen (sticta M^osa). (x 500.)
Cl’UStaceous grow- c, cortical or epidermal layer; g, gonidia;
■r.i’f ,	7i,hyphie.
mg as it they formed
part of the bark or rock to which they are attached.
PUCCINIA, ONE OF THE BASIDIA FUNGI
328. Occurrence.—Pueeinia graminis, wheat rust, is
common on cultivated wheat and other grains and also
on many wild and cultivated grasses besides the grains.
Numerous species of rust are known. A rust may have
one, two, or three kinds of spores, and when three occur256
ESSENTIALS OF BOTANY
one is known as the cluster-cup stage and the others as red
rust and black rust, according to the usual approximate
color of the spores. The rust called Puccinia graminis,
growing on wheat, has its cluster-cup stage on the leaves
of barberry in June. The spores from the cluster-cups
are carried by the wind to the wheat, where they germi-
nate and in a few days produce the red rust. A little
later the black spores appear, produced by the same myce-
lium. This growth is chiefly upon the stems and sheaths.
Fig. 181. A Cluster-Cap of Anemone Rust (Puccinia fusca). (x 120.)
chains of spores; p, the covering or per idium of the cup; h, hyphse.
329.	Cluster-Cup Stage, Gross Structure. — Procure if possible fresh
specimens of infected barberry leaves. If these are not available,
dried leaves soaked for a short time in water or (still better) leaves
preserved in alcohol may be used. With the magnifying glass note:
(a) The occurrence of the cups (atcidia ; singular cecidium). Are
they on the upper or lower surface of the leaf ?
(b)	The number of cups in a cluster.
(e) The form, size, and color of the cups.
330.	Cluster-Cup Stage, Minute Structure. —Cut a thin section of
a leaf through a cluster of cups. This can best be done by holding
the portion of leaf to be sectioned between two pieces of elder pith.1
1 If desired, prepared slides can be bought of the dealers.THE FUNGI
257
Examine first with m.p., and then with h.p. Note :
(a)	The forms of the cluster-cups at various stages of growth.
Compare with the cup on an anemone leaf, shown in Fig. 181.
(b)	The structure of the cup, surrounded by a layer of mycelium,
next to which comes theperidium, or wall of the cup. The latter is filled
with chains of spores (cecidiospores). Draw the cup with its contents.
(c)	The size and shape of the mature
spores which separate from the ends of
the chains.
(d)	The cavities, smaller than the
cluster cups and on the opposite surface
of the leaf. These produce great num-
bers of minute cells which now appar-
ently are of no service in the life of the
fungus, though the}' mayonce have been.
331.	Red-Rust Stage and Black-Rust
Stage, Gross Structure. — Examine with
the magnifying glass the surface of the
leaf sheaths and stems of wheat or other
grain or of quick grass (Agropyrum re-
pens') collected in early summer and other
specimens collected in autumn. Note
the rust streaks extending lengthwise
of the leaf sheaths and the stems. De-
scribe the precise color of these streaks
in the early- and the late-collected ma-
terial. Draw some of the best defined
streaks of each kind. In preserved mate-
rial the early rust may have lost a good
deal of its color.
332.	Red Rust, Minute Structure. —
Pick out with a scalpel or a knife point some spores (uredospores)irom
a streak of red rust. Tease the material out with dissecting needles
in a drop of water on a slide.1 Cover and examine with h.p. Note :
(a) The shape of the spores and the attachment of each to a
stalk (Fig. 182).
1 If the spores are dry, shrunken, and opaque they may first be soaked for
a few minutes in a five-per-cent solution of potassium hydrate.
t
Fig. 182. A Group of Spores
of Wheat Rust (Puccinia
gratninis). (x about 440.)
v, u, uredospores; t, a
teleutospore.258
ESSENTIALS OF BOTANY
(b) The rough outer coating and the inner coating -with (usually)
four pits or thin places in its wall about midway of the spore.
333. Black Rust, Minute Structure. — Re-
move a small mass of the black-rust spores,
(teleutospores), mount, and examine as de-
scribed in Sect. 332. Note:
(a)	The shape and attachment of the spores
(Fig. 182).
(b)	The structure of the spore (composed
of two cells) and the thickness of the cell-
wall. Look for thin places or germinating
pores in the cell.
334. Life History of Wheat Rust. —
This species of rust under favorable cir-
cumstances shifts from the barberry as
a host-plant to wheat or other grass and
back to the barberry again year after
year. The cluster-cup spores are borne
by the winds to grain or grass fields,
where they germinate and develop
red-rust streaks full of uredospores.
These spores are carried to other wheat
plants on which they germinate, and
so the growth of the fungus spreads.
In late summer or autumn the same
mycelium which earlier produced ure-
dospores forms only teleutospores and
the red-rust streaks turn blackish. The
teleutospores survive the winter and
in the spring germinate on barberry
leaves (Fig- 183), produce a new crop
of cluster-cup spores, and so on. Note that all these proc-
esses of spore formation are asexual; no gametes are known.
Fig. 183. A Germinat-
ing Teleutospore of
Puccinia graminis.
a, ci', threads produced
by the germination,
from the ends of which
grow short rows of
cells which bear basicl-
iospores, b. These are
carried by the wind
to the barberry host-
plant.THE FUNGI
259
335. Discussion. — The wheat rust is interesting to the
botanist on account of its singular variety of methods
of asexual spore formation. It is also of great practi-
cal importance, as it is a very dangerous enemy of the
grain farmer. Comparatively rust-proof species of wheat
are much in demand. Barberry bushes should never be
allowed to grow in wheat-raising regions, and in many
parts of England they have been nearly or quite exter-
minated by farmers. Where no barberries are found the
rust is carried from one
wheat crop to the next by
uredospores only.
PSALLIOTA, ONE OF THE
BASIDIA FUNGI
336. Occurrence. — The
common mushroom, Psal-
liota campestris (often
known as Agaricus campes-
tris), grows in open fields
and pastures in the United
States and Europe. It is the mushroom most extensively
cultivated for market, and if not found in the field it may
be raised from “ spawn ” (mycelium), put up in the shape
of bricks and sold by seedsmen in the large cities. Those
who make a specialty of selling it furnish directions for
culture. A moderately warm cellar or basement makes
an excellent winter garden for mushrooms.
There are many other gill fungi of frequent occurrence
besides the edible mushroom. Most of them are commonly
known as toadstools. Any of these may be collected for260
ESSENTIALS OF BOTANY
Fig. 185. Armillaria mellea (often known as Agaricus melleus).
This is a basidia fungus which can live either as a parasite or a saprophyte.
As a parasite it is very destructive to the roots of coniferous trees. A,
fructifications of various ages; c, every young “ buttons ”; st, the stem
or stipe; r, the ring (the remains of a membrane by which the margin of
the cap was at first attached to the stalk); g, the gills. B, branching myce-
lium spread out between the bark and the wood of the root of the host.
study, though, the directions which follow might require
in some cases to be slightly modified for other genera than
Psalliota.
337. Gross Structure__Secure a group of perfect specimens which
have been dug up with some of the mycelium attached. Note :
(a)	The division into an aerial fruiting portion,1 commonly called
the mushroom, and the underground mycelium, or “spawn.” Draw
the entire portion above ground.
(b)	The stages in the development of the cap and its stalk from
the “buttons” (Fig. 185, A).
(c)	The cap, gills, ring, and stalk of a fully developed mushroom.
Observe the mode of origin of the ring.
1 The word “ fruiting ” is often used with reference to spore-plants to apply
to the spore-bearing portions or the spore-producing condition.THE FUNGI
261
hym
(d)	The structure of the gills, as shown in a mushroom split
lengthwise through the stem and cap and examined with the mag-
nifying glass.
Cut off the stalk of a well-expanded mushroom or toadstool close
to the cap and place the latter, gills down, on a sheet of paper. If
the gills are light-colored use black paper, if dark-
colored, white paper. After some hours lift off
the cap and examine the print left by the spores.
(e)	The extent of the nuxelium as far as it
can be traced in the earth or other substratum
on which mushrooms or toad-
stools are growing.
338.	Minute Structure of the
Gills. — Cut thin sections of
one of the gills at right angles
to its flat surface. Mount and
examine first with m.p. and
then with h.p. If spores are
not shown, as in Fig. 187, re-
peat with part of a gill from
another mushroom. Note:
(а)	The general structure
of the gill, the interior consist-
ing of loosely interwoven hy-
phse and the external fruiting
portion, the hymenmm, consist
ing of ends of hyphae definitely
arranged. What is their position relative to the surface of the gill ?
(б)	The basidia, or club-shaped tips of spore-bearing hyphse.
(c)	The sterigmala, or short stalks on the basidia, each sterigma
bearing a spore.
(d)	The size, shape, and color of the spores and the number borne
by each basidium.
(e)	The sterile filaments parallel to the basidia and lying between
them.
339.	Discussion. — The gill fungi (including most of the
toadstools and mushrooms) are some of them saprophytic
Fig.
186. Portions of Gills of a
Fungus (Agaricus).
A, slightly magnified. B, one of the parts
of A, more magnified; hym, hymenium ;
h, central layer.262
ESSENTIALS OF BOTANY
and some of them parasitic. A few may live in either
fashion at will. The mycelium through which the plant
obtains its nourishment is often so fine and inconspicuous
that it escapes notice, and the fruiting portion is com-
monly thought to spring directly from the earth, bark,
wood, or other substratum to which it is attached. The
reproduction is wholly asexual.
Gill fungi are of consider-
able economic importance. A
good many are edible (though
others which resemble them are
actively poisonous). Such par-
asitic species as Armillaria mel-
lea (Fig. 185) are very injurious
to timber. This fungus sends
its mycelium through the bark
or between the bark and wood
of trees and often causes the
death of the host.
A large shelf-fungus (Tra-
metes Pint) of a closely related
group (Fig. 184) is very destruc-
tive to trees of the Pine family.
The lack of sexual reproduc-
tion in organisms as compli-
cated as the gill fungi seems
to be evidence that these forms are degenerating. The
same conclusion is suggested by the occurrence of what
appears to be imperfect reproductive apparatus of Puccinia
on the upper surfaces of infected barberry leaves. There
is much other evidence of the same sort, and it all agrees
with the supposition that fungi are degenerate descendants
Fig. 187. Part of the Preceding
Figure, (x about 300.)-
C, layer of cells immediately under
the hymenium. s, s', s", three
successive stages in growth of
spores.TIIE FUNGI
263
of algae. Habits of parasitism, whether among animals or
plants, very frequently cause them to become less perfectly
developed than their nearest non-parasitic relatives.
The economic importance of some fungi has been already
mentioned (Sects. 311, 313, 316, 326, 335). No sweeping
statement can be made that fungi are generally useful or
generally injurious. They benefit man not only by directly
furnishing a few articles of food, but also by helping to
destroy dead animal and plant matter. This would remain
forever without decaying if it were not for saprophytic
fungi, especially bacteria, and thus the available raw mate-
rial for making plant food would soon be exhausted and
all life and growth cease. Certain bacteria which live on
the roots of plants of the Pea family serve to convert the
nitrogen of the soil-air into nitric acid available for use
by the plant to which the bacteria are attached. Vast
amounts of food for animals are thus produced.
Fungi injure man by causing diseases in useful, wild,
and cultivated plants, in domestic animals, and in human
beings. The importance of bacterial diseases may be
partly understood from one striking instance. The Black
Death of the fourteenth century is considered to have
been due largely to the attacks of the bacillus, which
causes the bubonic plague. That single epidemic caused
the death of about twenty-five million people.
340. Additional Notes on the Fungi.— Only a few species
of fungi, out of some forty thousand that are knowm, have
been outlined for laboratory work in the present chapter.
The student can, however, hardly fail to learn from these
studies something of the extreme divershy of fungi in
almost every respect except the one general characteristic,
inability to live on inorganic material, that is, to do the264
ESSENTIALS OF BOTANY
work of photosynthesis. Fungi are therefore destroyers of
food, and (like animals) on the ivhole lessen the total amount
of organic matter on the earth, while green plarits tend to
increase it. In fungi, formation of fat or oil, especially as
reserve material, takes the place of the starch making so
common in plants with chlorophjTl.
As regards their mode of life, fungi may be roughly di-
vided into three groups: (1) pure saprophytes; (2) plants
which are saprophytic or parasitic according to circum-
stances ; (3) plants which can only reach their full de-
velopment as parasites. Several of the classes of fungi
mentioned in Sect. 305 contain representatives of all three
of the groups given above. The common mushroom is
a familiar example of the first group, Armillaria mellea
(Fig. 185) is a member of the second group, and the rusts
of Figs. 181—183 belong to the third group.CHAPTER XXVI
THE BRYOPHYTES
341. Classes of Bryophytes. — The bryophytes, or moss-
like plants, are divided into:
Class 1. Liverworts.
“	2, Mosses.
It is not easy to state in an untechnical way all the
distinctions between the two classes. One main difference
is that most liverworts either show no distinction between
stem and leaves, or if they possess leaves at all do not have
Fig. 188. Hicciocarpus, an Aquatic Liverwort.
A, whole plant, gametophyte (natural size); B, one lobe showing
a few rliizoids. (Somewhat magnified.)
them arranged spirally. Moss leaves are borne in spiral
rows. The whole plant body of the liverworts has an upper
and an under side, while that of the mosses does not.
265266
ESSENTIALS OF BOTANY
MARCHANTIA, ONE OF THE LIVERWORTS
342. Occurrence.—Marchantia polymorpha} the com-
monest species of the genus, is widely distributed in this
country and in Europe. It is found on damp soil or rocks,
especially in shaded places.
343. Gross Structure. — Secure
if possible specimens in the fruit-
ing condition (Figs. 100, 191).1 2
Examine with and without the
magnifying glass and note :
(a)	The size, shape, and color
of the thallus or body of the plant.
(b)	The mode of forking.
Branches are formed in pairs on
each side of the growing tip. Do
they develop equally?
(c)	The distinctions between
the upper and the lower surface
of the thallus. Look for scales
on either surface and for rhizoids
or root-like organs. Examine the
upper surface with the magnify-
ing glass and draw a portion of it, showing the diamond-shaped areas,
each with a pore in its center.
(cl) The buds, or organs of vegetative reproduction, small struc-
tures which, when detached, serve to produce new plants.
(e) The mcde receptacles, stalked disks with scalloped margins.
Fig. 189. Vertical Section through
a Lobe of Ricciocarpus. (Magni-
fied.)
u,antheridium; e, epidermis; i, spongy
interior of thallus with air-chambers;
/■, bases of rhizoids.
1	If Marchantia cannot be easily obtained, Lunularia, a genus very com-
mon in greenhouses, may be substituted. It is easily recognized by the cres-
cent-shaped cups in which the reproductive buds are borne. The structure
is rather similar to that of Marchantia and the mode of vegetative reproduc-
tion is the same in both. Lunularia as found in our greenhouses does not
undergo sexual reproduction.
2	M. disjunct a, which is shown in these figures, differs considerably in the
form of the receptacles from M. polymorpha. The male receptacle of the
latter looks a good deal like the female receptacle of the former but is much
shorter-stalked.THE BRYOPIIYTES
267
Fig. 190. Part of Male Thallus of a Liverwort (Marchantia
disjuncta). (Enlarged.)
mr, male receptacle.
Fig. 191. Part of Female Thallus of M. disjuncta. (Enlarged.)
fr, female receptacle; c, cups with buds.268
ESSENTIALS OF BOTANY
Fig. 192. Section through An-
theridial Receptacle of Mar-
chantia. (Magnified.)
u, antheridium.
(/) The female receptacles, stalked structures with finger-like re-
curved arms radiating from the center. With the magnifying glass
examine the under surface of a very
mature receptacle and note the young
sporophytes, or spore-plants, hanging
from the receptacle. Draw.
344. Minute Structure of Thallus
and Buds. — Cut thin cross-sections
of the thallus and examine with l.p.
and then with m.p. Note :
(a)	The general structure of the
thallus, with a firm upper epider-
mis, spongy parenchyma beneath it
(which serves for the storage of re-
serve food materials), and a thin
lower epidermis.
(b)	The air-chambers beneath the
pores, each containing many short
branching threads, made of pear-shaped cells.
Compare these cells with others of the thal-
lus as regards the number of chlorophyll
bodies which they contain. What effect do
these cellular threads have on the amount
of surface for photosynthetic work in the
air-chamber V
(c)	The rhizoids. From which surface
do they spring ? Are they all alike ?
Make a drawing to illustrate the general
structure of the thallus, showing position
of the air-chamber and attachment of the
rhizoids. Make a detailed, highly magni- _ ino e ..	,
.	’ a j o	Fig. 193. Sectional! lew
tied drawing of the air-chamber.
Pick" out from the cups several buds and
examine them with m.p. Note :
(a) The shape of the buds.
(?>) The notches which show the posi-
tion of the growing points of the bud. How many are there?
(c) The minute stalk of each bud. How is this attached?
of an Antheridium of
Marcliantia.
a, antheridium; s, sperms.
(X 700.)THE BRYOPHYTES
269
345.	Minute Structure of the Male Receptacle and Antheridia.—
Make thin vertical radial sections (in pith) of a male receptacle and
examine with l.p. and m.p.1
Note:
(a) The flask-shaped
cavities in which the an-
theridia are borne. Where
do they open ?
(h) The antheridia of
various ages, each with a
stalk bearing a sperm-case.
(c) In water in which a
fresh male receptacle has
been left for a short time
look with l.p. for moving
sperms. Kill them with
iodine, run water under the
edge of the cover-glass,
study, and draw. Or crush
a mature antheridium from
preserved material and
study the sperms.
346.	Minute Structure of
the Female Receptacle and
Archegonia. — Cut thin ra-
dial vertical sections (in
pith)of young female recep-
tacles, making the sections
pass through the portions
between the rays, or arms.
Fio. 194. Female
Receptacle of Mar-
chantia (lengthwise
section, consider-
ably magnified).
c, canal in neck of arckegonium; r, egg in
arckegonium; p, breathing pore; chi. cells,
in air-chamber, containing chlorophyll; l,
lobe of the receptacle; s, fringed appendages
of receptacle.
If possible use also prepared slides of microtome sections. Examine
with m.p. and note :
(a) The archegonia of various ages. "Where are the youngest?
(5) The parts of an archegonium, — a short, stout stalk, an en-
larged body, or venter, and a slender neck. Draw.
(c) Inside of the venter in the older archegonia an egg. Draw.
l Prepared slides of microtome sections will show the relative positions of
the parts more clearly.270
ESSENTIALS OE BOTANY
347.	Minute Structure of the Sporophyte.—Pick out from old re-
ceptacles some of the full-grown sporophytes, mount, and examine
with m.p. Note:
(a)	The foot (which was imbedded in the receptacle), the slender
stalk, and the enlarged spore-case. Draw.
(b)	Spores.
(c)	Elaters, spirally-marked cells which assist in scattering the
spores. Draw (b) and (c) under h.p.
348.	Discussion. — Marchantia is far more highly spe-
cialized for utilizing the raw materials of plant food than
are any of the algte or fungi studied in previous sections.
Its thalius has a well-defined
epidermis, especially firm on
the upper surface to pre-
vent undue loss of water.
The rhizoids are efficient in
absorbing water containing
nutrient substances from
the earth. The air-cham-
bers beneath the upper sur-
face of the thalius, with
their hair-like chlorophyll
apparatus, are admirably
adapted for photosynthesis.
Asexual reproduction is
well attained by the separation of young branches (set
free by the dying of the older parts) and by the numer-
ous buds.
The sexual reproduction is of a complicated character,
brought about by the conjugation of unlike gametes.
349.	Alternation of Generations. — In the reproduction
of Marchantia for the first time in the studies of spore-
plants outlined in Chapters xxm-xxvii, the student fully
Eig. 195. Frullania, a Leafy Liver-
wort, growing on maple bark.
(About natural size.)THE BRYOrHVTES
271
encounters what is known as alternation of generations.1
By this is meant the descent of a spore-bearing plant, or
sporophyte, from a sexual plant, or gametophyte, then the
descent of a gametophyte from the sporophyte, and so on
indefinitely (see Sect. 357).2 In Marchantia the sporophyte
is a minute organism, incapable of separate existence and
living much like a parasite
on nourishment drawn from
the female receptacle.
350. Summary of the Liv-
erworts. — The liverworts
show a distinct advance in
complexity over the algae.
This appears particularly in
the excellent facilities pos-
sessed by such forms as Mar-
chantia for photosynthesis
and respiration, as land
plants. It is also shown by
the complicated process of
sexual reproduction, matur-
ing the egg in a many-celled
archegonium and not in a
one-celled organ such as is
found among the thallophytes
(e.g. Fig. 163). Alternation of generations is another in-
dication of an advanced position in the plant world. It
is important to note that while the majority of liverworts
are terrestrial they all have ciliated sperms, a characteristic
1	This also occurs in a less evident form in red algse and in some sac
fungi.
2	The student may be asked to make a diagram of the life history of Mar-
chantia on the plan of Fig. 203, or an illustrated one somewhat like Fig. 208.
Fig. 196. A Small Portion of
Fig. 195 enlarged.
s, the stalked spore-capsule.272
ESSENTIALS OF BOTANY
■' A'- ..
/A;
- *

MM,
Fig. 197. Peat-
Moss (Sphag-
num).
of aquatic plants, and water
is absolutely necessary to ac-
complish fertilization.
Some liverworts are mi-
nute floating plants (Fig.
188) much simpler than Mar-
chantia, others are terrestrial,
of more complex organization than Mar-
ch rutin.. Many of .the higher liverworts
(Fig. 195) have leafy stems and in appear-
ance slightly resemble the mosses.
MNH’.tr, A COMMON MOSS1
351. Occurrence.—Mnium cnspidaturn is
a very widely distributed moss occurring
abundantly on shaded ground and espe-
cially about the bases of trees in open
woods. It may be known by the yellow
or light brown ellipsoidal capsule, which is
attached, at right angles or slightly droop-
ing, to a slender stalk about an inch long.
The leaves of the vegetative branches are
round-obovate and pointed by a minute pro-
longation of the midrib. They have minute
sharp teeth and, in fresh moist material, are
pale green. The capsules are produced in
the spring, and material showing various
stages of development should be collected.
1 Any of the common mosses, Bryales, will answer for this study. At rich inn
anr/ustutum is of frequent occurrence in woods and on sandy hills. Funaria
hygrometrica is common on bare ground and especially on burnt-over places.
Two species of Jin/urn. are widely distributed, and Pohjtrirhum commune, a
very large moss, is found abundantly in open woods and pastures in the north.THE BRYOPHYTES
273
Fig. 108. Milium undulation, a Moss.
A, female plant with four spore-capsules s; B, male plant with
antheridia at a.
352. Gross Structure of the Complete Moss-Plant. — Procure a leafy
plant with a capsule growing from it and note:
(a)	The steal. Js it branched or unbranched ?
(b)	Tlie leaves. How arranged?
(c)	The liiizoids.
(d)	The spnrophyte, or spore-bearing plant, with a slender stalk
bearing the capsule. Draw the leafy plant with the sporophyte x 2.274
ESSENTIALS OF BOTANY
353. The Protonema.— Look in the neighborhood of patches of
moss for a felt-like network of green threads covering the ground.
It is most readily found on the earth of flower-pots in greenhouses.
Mount some filaments in water and examine with m.p. Compare
with Fig. 199. Invert a patch of moss in a plate with water, cover
prim, primary shoot; h, a young root-hair; pi, young moss-plant; br,
branches ofprimary shoot.
with a bell-glass in a sunny place, and note any changes that may
after some weeks occur in the appearance of the exposed rhizoids.
Explain.
354. Minute Structure of the Gametophyte, Vegetative Portion.—
Examine with m.p. a microtome section of the stem near the base.
Note:
(«) The central strand of small cells.
(b)	Intermediate tissue of larger thin-walled cells, followed near
the exterior by thicker ones.
(c)	The epidermis.
(d)	The rhizoids (not present on the upper parts of the stem)
springing from the epidermis. Draw.
Examine a leaf with 2-inch objective and then with m.p. Note :
(a) The midrib, of mechanical cells.THE BRYOPIIYTES
275
(6) The blade, of thin-walled
cells containing many chlorophyll
grains.
(c) The border, of strengthening
cells, some projecting into teeth.
Draw.
355.	Minute Structure of the Gam-
etophyte, Reproductive Portion.—
Dissect with needles, in water, on
a slide, the tufts of leaves found at
the tips of some stems.1 Note :
(a)	The antheridia, oval sacs grow-
ing from the enlarged tips; tips of
the stem (see Fig. 201 for a single
one much magnified).
(b)	The areliegonia, flask-shaped
structures arising from the tip of the
the stem (Fig. 202).
(c)	The sterile filaments inter-
mixed with the sex organs (Fig.
202.) Are the antheridia and arclie-
gonia of Mnimn cuspidatum borne in
the same leaf tuft or separately?
Draw (a), (b), and (c) in position.
356.	Minute Structure of the Spo-
rophyte. — Procure plants showing
sporophytes in various stages of de-
velopment. Draw a series of these,
attached to the tips of the leafy stems
from which they grow. Boil some
stems with attached sporophytes in
five-per-cent potash solution for a
few minutes, rinse with water, care-
fully pull out the sporophyte from
the tip of the gametophyte, and
1 It will be of decided advantage also
to study prepared microtome slides of
longitudinal sections of these tufts.
Fio. 200. Development of Sporo-
phyte of a Moss (Funaria).
A, a very early stage, showing the
cell-divisions of the egg; B, the
sporophyte lengthening rapidly
and about to tear off the arche-
gonium, which will be carried up
as the hood of the spore-capsule.
The base of the sporophyte is fas-
tened to the tissues of the game-
tophyte (leafy moss-plant), into
which it is inserted for a consid-
erable distance; a, archegonium ;
p, gametophyte; s, sporophyte.276
essentials of botany
m
u, antheridium ; b, escaping sperms
(X 350); c, a single sperm of an-
other moss (X 800).
of plant (x 100); «, archegonia; l,
leaves. /», an archegonium (X 550);
e, enlarged ventral portion with cen-
tral cell; 7i, neck; m, mouth.THE BRYOPHYTES
277
note the pointed foot which was imbedded in the gametophyte
(Fig. 200).
Study young and full-grown sporophytes and note:
(a) The slender sialic.
(ib) The enlarged capsule.
(c)	The hood or calyptra which covers the young capsule. Cut-
ting off and mounting in water the ends of capsules of various ages,
examine with m.p. and note:
(d)	The lid covering the	ra.melop^’jte
mouth of the capsule.	atvd	-w''.ss.
(e)	The fringe of teeth	if-0!
at the mouth. How many
rows are there?
(/) The spores (best seen
with h.p.).
Draw the structures
above described (a-f).
Fig. 203.
Diagram of Life History
of a Moss.
An, antheridium; -Jr. arehegonium; s, sperm;
e, egg-cell; e', egg.
357. Discussion.—
The leafy moss-plant,
or gametophyte, is more
highly organized than
such liverworts as Mar-
chantia, since the moss has well-differentiated stems and
leaves. It is also more specialized even than liverworts
which bear leaves, since the moss stem has a more compli-
cated structure than that of any leafy liverwort.
The sporophyte of mosses is more highly developed
than that of most liverworts and far more so than the
Marehantia sporophyte. The elevated position of the cap-
sules and the expansion of the fringe of teeth at the mouth
of each capsule assist in dispersing the spores. Although
the sporophyte has some stomata and can do a little photo-
' synthetic work, it must draw its supply of water and min-
eral matter from the leafy stem out of which it springs.278
ESSENTIALS OF BOTANY
It therefore leads a half-parasitic life like such seed-plants
as the mistletoe.
The life history of a moss is as follows : The spore on
germinating forms a network of protonema, often of con-
siderable extent. This protonema finally produces buds
(Fig. 199, pi), which grow into leafy moss-plants (gameto-
phytes). These bear the non-sexual sporophytes, and so
on in a series of alternating generations (see Sect. 349).
Some mosses produce antheridia and archegonia in the
same leaf-cluster, while others produce only one kind of
sex organ in a cluster. In case the sexes are separated
the male plants bear the antheridia at the summit within a
sort of basin-shaped rosette or circle of specialized leaves,
which are often colored (not green). The female plants
bear the archegonia. at the tips of the branches, where they
are hidden by closely appressed leaves of the usual sort.
Fertilization of the egg in the archegonium takes place
when the sex organs are wet by rain or dew. The sperms
are washed into the opening of the archegonium and make
their way through the mucilage which fills its neck until
they reach the egg at the bottom of the cavity.
358. Summary of the Mosses------The mosses form a more
united group than the liverworts, differing less among
themselves in vegetative habit and in the details of their
reproduction. None of the mosses are thallus plants and
no whole order of mosses is aquatic, though some genera
are so. Mosses are evidently far more successful plants
than liverworts, as is shown by the fact that they are so
numerous and so widely distributed. This is clue in part
to their reproductive power and also in part to the capacity
of some of them to endure great extremes of heat and cold,
moisture and dryness. The mosses, like the liverworts,THE BRYOPHYTES
279
have the aquatic character of possessing ciliated sperms,
and water is necessary to accomplish fertilization.
359. Additional Notes on the Bryophytes. — The bryo-
phytes are the lowest land plants which have stems and
leaves. Some of the lower ones, like Pdccia and Mar-
chantia, have only a thallus and do not show a differentia-
tion into stem and leaves. The bryophytes in this respect
are intermediate between the thallus plants, such as algae
and fungi, and the pteridophytes, or ferns and fern-like
plants (Sect. 360). Bryophytes have no fibro-vascular bun-
dles. They are superior to the thallus plants in the com-
plexity of their reproductive apparatus, developing the egg
in a many-celled archegonium.
True roots are wanting in the bryophytes. In the liver-
worts one-celled rhizoids and in the mosses rhizoids consist-
ing of simple rows of cells perform the work of roots.
Liverworts have no economic value and form but an
insignificant part of the vegetation of the earth, flosses,
however, though none of them are very large plants, form
an important part of the vegetation particularly of northern
regions. Common mosses carpet large areas in woodlands
and serve to prevent the rapid draining away of surface
water after rains. In this way they help to maintain the
constant flow of springs and rivers. Peat-mosses occur in
immense numbers in bogs in various parts of the world.
The dried moss is used as bedding for horses, and in a
moist condition it is used by nurserymen and florists in
packing plants. In extensive bogs large quantities of dead
moss, sedges, and other plants may become accumulated
under a layer of living plants, and the material resulting
from their partial decay is known as peat. Dried (with or
without compression into blocks) it is of use as fuel.CHAPTER XXVII
THE PTERIDOPHYTES
360. Classes of Pteridophytes. — This series of the ferns
and fern-like plants is, among other characteristics, distin-
guished from all other spore-plants by having much more
highly developed tissues. From the presence of vessels
the pteridophytes are often known as vascular spore-plants.
They are divided into
Class 1. The ferns.
“	2.	The horsetails.
“	3.	The club-mosses.
The distinctions between these classes are some of them
highly technical, but there are a few obvious characteristics
which may be briefly stated.
The ferns have usually well-developed leaves, which are
oiiten highly compound (Fig. 204). They are frequently
rolled up in the bud. Sometimes there are special spore-
bearing leaves, but usually the spores are borne on the
under surfaces of the ordinary foliage leaves.
The horsetails have very small undivided leaves, ar,
ranged in whorls. The spores are borne on specialized
shield-shaped leaves, arranged in a sort of flower-like
cluster (Fig. 211). The branches are whorled.
The club-mosses and their allies have mostly very small
and simple, often scale-like or needle-like, spirally arranged
280Fig. 204. Spore-Plant of a Fern (Aspidium Filix-mas).
A, part of rootstock and fronds, not quite one-sixth natural size; fr, young
fronds unrolling (not usually found at the same season as the mature
fronds); B, under side of a pinnule, showing sori s; C, section through a
sorus at right angles to surface of leaf, showing indusium i, and sporan-
gia s; JO, a sporangium discharging spores. (B is not far from natural
size. C and D are considerably magnified.)
281282
ESSENTIALS OF BOTANY
leaves. In some cases the spore-bearing leaves are ar-
ranged in spherical cones (Fig. 213), while in others
spores are borne by the ordinary leaves scattered along
the stem.
361. Occurrence of Ferns.—Many of our commonest
ferns are shade-plants, flourishing in moist woods, but
there are widely distributed species, such as the bracken
fern (Pteris aquilina), which grow readily in full sunshine.
A few, such as Notholcena, Cryptogramma, Polystichum,
and Pellcea, are decided xerophytes, growing usually on
nearly bare rocks. Some species are highly local in their
distribution, occurring only in a few localities, often of
very limited area.
ASPLENIUM, A FERN
362. Gross Structure.1 — Using fresh or preserved material for the
underground portion and fresh material or dried and pressed herba-
rium sheets2 for the portion above ground, note :
(a)	The color, size, shape, and appendages of the rootstock.
(b)	The mode of development of the leafy portion of the plant
from the rootstock (Fig. 201).
(c)	The mode of origin of the leaves, or fronds, from the root-
stock and their general form and the amount and manner of division.
The main axis is called the rhachis, the leaflets pinner, and their sub-
divisions pinnules. Draw a leaf.
(</) The sori, or fndt-dols, on the under surface of the leaves.3
Draw a group of sori, as seen with the magnifying glass.
1	This outliue applies in detail only to Asplenium JUix-faninna, a species
common in moist woods, though with slight modifications it will apply to any
Asplenium and, in considerable part, to most genera.
2	Fronds, or parts of fronds, may also be mounted like passepartout-framed
pictures, between two sheets of glass, and are very convenient to pass from
hand to hand, showing both sides of the frond.
8 In tho bracken fern (Pteris) and the maidenhair fern (Adiantum) the
spore-cases are borne near the edges of the leaves and covered by the incurved
edges of the frond.Photograph by Soule Piiotogruph Co.
Plate XI. Tree Ferns.THE PTERIDOPHYTES
283
363.	Asexual Reproduction, Spore-Cases and Spores.1 — Pick out
some spore-cases from a sorus (Fig. 204, C, D), mount them in water,
examine with l.p., and note :
(a)	The stalk.
(b)	The spore-cases proper. Draw.
(c)	The partial ring of thick-walled cells enclosing the spore-case.
(d)	The spores. These should also be examined with h.p. Draw.
The spores are scat-
tered by the splitting
open of the spore-case
when very dry, pulled
apart by the elastic ring
(Fig. '204, D).
364.	The Gameto-
phyte (Prothallium) and
Sexual Reproduction. —
Material for this study
may be obtained by
dusting spores of any
desired species of fern
over bits of brick or
broken flower-pots or
earth kept moist under
a bell-glass. The spores
of most genera are long-
lived and germinate
readily many months
after they mature. They
should be sown six
weeks or more before
the material is needed
for class use. Germinating spores in all stages of development may
also be found on flower-pots containing greenhouse species of fern,
particularly Adiantum. Mount some of the material, examine with
h.p., and note :
(a) Several stages in the germination of spores. Draw.
1 Polypodium is excellent material for the study of the sporangia. The
minute structure of the vegetative portion of the feru is here omitted.
-S
Fig. 205. Prothallium of a Fern (Polystichum).
View of the under surface.
gp, growing point; or, archegonia; an, anther-
idia; rh, rhizoids; s, region in which the spore
germinated. (X about 8.)284
ESSENTIALS OF BOTANY
(b)	Fully formed protliallia (Fig. 205) with antheridia, arche-
gonia, and rhizoids. These may best be seen with l.p. in a prothal-
lium that has been held by delicate forceps and washed with a gentle
stream of water from a wash-bottle. The prothallium should then be
mounted, bottom side up, in a concave ground-slide and examined as
an opaque object and also by transmitted light.
(c)	Protliallia which are developing young fern-plants (Fig. 206).
In some of these study with h.p. the distribution of the chlorophyll
Fig. 206. Development of the Sporopliyte of a Fern. Vertical section
through prothallium.
an, antherozoids; or, arehegonia; c, thickened cushion, in which the foot of
the young fern-plant is imbedded; rh, rhizoids; l, first leaf; r, root.
(Magnified.)
bodies in cells of the prothallus. Draw. Study with l.p. the struc-
ture and veining of the young fern leaf. Draw.
Procure some dwarf protliallia that have been growing much
crowded together and then kept for a day or two with very little
water. Mount in water, examine with h.p., and look for;
((/) Antheridia best seen on the margin of the prothallium. Draw,
(e) Sperms, swimming about in the water. Stain these with
iodine and draw, showing the body of the sperm an'd its tuft of
cilia.
In prepared slides, if any are attainable, study the structure of an
archegoniuin, noting:
(/) The enlarged ventral portion.
(//) The elongated neck. Neck canal cells and ventral canal cell.
(7i) The egg within the ventral portion.1 Draw.
1 See Bergen anil Davis’ Princii/lrs of Botany, pp. 316, 317.the pteridophytes
285
365. Discussion---The life history of a fern differs in a
striking way from that of a liverwort or moss. Ascending
Pig. 207. Diagram of Life History of a Fern.
An, antheridium; Ar, arcbegonium; s, sperm; e, egg-cell; e', egg.
from the lower forms of plant life to the higher ones, it is
only when the ferns are reached that alte rnation of genera-
tions is shown in its most complete form. By this term a
Fig. 208. Illustrated Life History of a Fern.
(The young fern-plant is Onoclea, Fig. 209.)
process of reproduction is meant in which the offspring
resemble closely not the parent but the grandparent, as286
ESSENTIALS OF BOTANY
is shown in the diagram (Fig. 208). In the mosses and
their allies the full-grown plant is a gametophyte, and the
spore-bearing plant or sporophyte appears as a sort of par-
asitic outgrowth of the
gametopjhyte (Sect. 357).
In the ferns and their
allies the full-grown
plant (that which we com-
monly call a fern) is an
asexual sporophyte, am-
ply provided with vege-
tative organs, i.e. roots,
stem, and leaves, often
capable of living for
many years and attain-
ing the dimensions of a
tree. The gametophyte
(prothallium) in ferns is
a minute, usually short-
lived structure, and ex-
ists simply to mature an
egg which may produce
a fern-plant.
366. Summary of the
Ferns. — Most ferns are
land plants, but there
is one order of aquatic
ferns, some of which live
floating freely in water and others grow rooted in the
mud. Ferns vary greatly in size, the smallest genera not
being nearly as large as some mosses, while others are tree-
like. With abundant vessels, rigid tissue for strengthening
Fig. 209. Sensitive Fern (Onoclea).
s, sterile or vegetative frond; /, fertile frond
or sporopkyll.THE PTERIDOPIIYTES
287
purposes, and various kinds of parenchymatous tissue set
apart for different offices in the stem and leaves, ferns
have a higher vegetative organization than the simplest
seed-plants. The leaves are well furnished with stomata
and the work of photosynthesis is amply provided for.
Pteridophytes constitute the lowest
group of plants which have true roots.
The reproductive processes of ferns
are of a higher grade than those of liv-
erworts and mosses, but not a*s highly
developed as those of horsetails, club-
mosses, and Selaginella (Sects. 371,374).
EQUISETUM, A HORSETAIL
367. Occurrence. — The commonest
horsetail, JEquisetum arvense, occurs
widely distributed throughout the
United States. It is frequently found Pig. 210. AWaterPern
growing on railroad embankments and
on sand-hills. The fruiting stems ap-
pear verjr early in the spring and are short-lived. The
sterile vegetative stems follow and become well grown
during June.
(Marsilia).
s, spore fruits.
368. Gross Structure. — Make use of herbarium sheets of plants
with fertile and with sterile stems, or sheets of one and fresh material
of the other.
I.	Study the position, form, and size of the rootstocks and the
places at which roots and stems arise from these. Are there any
attached tubers?
II.	Study the fertile stems, noting :
(a) The shape of the stem as a whole. Is it solid or hollow ?288
ESSENTIALS OF BOTANY
(b)	The circle of sheathing leaves at each node. Are the leaves
entirely separate from one another ? Split a stem lengthwise through
a node and examine it with the magnifying glass.
(c)	The cone at the summit of each stem, composed of spore-
hearing scales. Examine these scales with the magnifying glass to
determine their shape. Draw the fertile stem.
III. Study the sterile stems, noting :
(а)	The position, arrangement, and number of the branches.
(б)	The form of the branches and their resemblances to and
differences from the stem. Draw part of a sterile stem and a
slightly magnified branch.
369.	Minute Structure____Cut thin sections of a fertile and a
young sterile shoot between the nodes.1 Mount in water and ex-
amine with l.p. and m.p. Note :
(а)	The general shape of the section.
(б)	The external grooves and ridges.
(c)	The stomata.
(d)	The position of the portions of tissue containing chlorophyll.
Is it present in both kinds of stem ?
(e)	The fibro-vascular bundles.
(/) The air-passages, one in the center and two other sets sur-
rounding it. Draw.
370.	The Spore-Leaves. — Using fresh or preserved material, pick
off a few spore-leaves from one of the cones. Put them in water in
the cavity of a slide with concave center. Examine with the mag-
nifying glass, or, if convenient, with a two-inch objective. Note :
(a) The stalk of the spore-leaf.
(h) The number and mode of attachment of the sporangia, or
cases in which the spores are produced. Draw.
Tease apart some sporangia in water, mount, and examine with
m.p. Note :
(c) The spores, with attached bands known as elaters. Mount in
water some fresh spores or those that have been merely dried, ex-
amine without a cover-glass, and note the movements of the elaters
as the water evaporates. Draw.
1 .Sections ot the mature sterile stems are difficult to cut. Prepared slides
of these and (for comparison) of one of the large perennial-stemmed species,
as Equisetum hiemale, may he bought of dealers iu microscopical material.THE PTERIDOPHYTES
289
Pig. 211. A Horsetail (Equisetum sylvaticum) ■
At the right is a colorless fertile stem, in the middle a green sterile
one, and at the left a green fertile one.290
ESSENTIALS OF BOTANY
371. Discussion. — The horsetails of the present day
number only about forty species, but they are the insig-
nificant descendants of what was in
earlier times a highly important class
of plants, often tree-like in size.
The work of photosynthesis in Equi-
setum is wholly performed by the green
tissue of the stems and branches, not
at all by the scale-like leaves. The
stomata occur in the channels which
run lengthwise of the stems. The thick
flinty epidermis and well-developed
rigid tissue under the epidermis, to-
gether with the moderate amount of
plant-surface exposed to the air, make
the horsetails decidedly xerophytic in
their structure.
Some horsetails, particularly E. hip-
male, have so much silica in the epi-
dermis that they were formerly much
used and are still somewhat employed
to polish tinware and other metal sur-
faces. Hence were derived the common
names scouring-rush and gunbright.
Equisetum differs from ferns in having
the spore-bearing leaves grouped into
a cone. This is a distinct advance
Fig. 212. A Lobe of
the Mature Female
Prothallium of Equi-
setum. (x about 50.) toward the flower-bearing condition of
a, mouth of a fertilized seed-plants. The species of Equisetum
archegonium. studied has pale fertile stems, living
almost like parasites at the expense of material drawn from
the rootstock and wholly set apart for spore production.THE PTERIDOPHYTES
291
Other species, however, like JE. sylvaticum (Fig. 211) and
E. hiemale, have part or all of the stem both green and
fertile.
The gametophytes of Equisetuui are produced from the
germinating spores very much as are those of ferns. The
prothallia are always of one sex only, and the female ones
are of a very irregular shape, having many lobes (Fig. 212).
From the manner in which the spores cling together by
means of their elaters, male and female prothallia are likely
to grow side by side and thus insure fertilization.
While the ferns, horsetails, and club-mosses are essen-
tially land plants, they all show their aquatic ancestry (as
do the bryophytes) by the possession of ciliated sperms.
That period of their life history which is concerned with
sexual reproduction is distinctly aquatic. The presence
of water is absolutely necessary in order that the sperms
or male gametes may swim to and reach the archegonia
and thus bring about the fertilization of the egg.
THE CLUB-MOSSES1
372. Occurrence. — The best-known and most conspicu-
ous club-mosses belong to the two genera Lycopodium and
Sdaginella. The former is well represented in the woods
of temperate climates and is well known throughout much
of the United States as “ Christmas evergreen,” largely
used in holiday decorations. Sdaginella occurs to some
extent in temperate climates, but most of the five hundred
species2 are tropical.
1	As the detailed study of the Lycopodinex is mainly interesting: on account
of its hearing on the evolution of plants, no laboratory work is here given.
2	This number is only approximate.292
ESSENTIALS OF BOTANY
373. Form and Structure. — The general appearance of
many species of Lycopodium is very similar to that shown
in Fig. 213. Selaginella is most familiar to people who are
not botanists from the species often grown in greenhouses.
Fig. 213. Plant of Lycopodium (L. annotinum).
It has somewhat the appearance of a large leafy moss-plant,
with the leaves arranged in four rows.
The structure of the stems and leaves of the club-
mosses is somewhat complex. They have well-developed
fibro-vascular bundles with sieve-tubes.
374. Reproduction; Heterospory. — In Lycopodium the
leafy (asexual) plant produces an immense number ofTHE PTERIDOPHYTES
293
spores from spore-leaves which are sometimes grouped in
a cone at the end of the stem and sometimes scattered
along the stem. No gametophytes of our species of the
northern United States have been found, and therefore re-
production in these must be by division of the stem or by
certain buds specialized for this purpose. Selaginellci pro-
duces two sorts of asexual spores. Of these the smaller
kind develops into male and the larger into female gameto-
phytes. From the fertilized female gametopliyte a young
(asexual) spore-plant is produced.
The term heterospory is applied to the condition of
plants which (like Selaginella) bear two kinds of asexual
spores from which are developed two kinds of gametes.
Heterospory begins among the pteridophytes with certain
ferns (Sect. 3S2), though most ferns have all their spores
alike. The highest of all plants (seed-plants) are hetero-
sporous, producing a smaller kind of spore, the pollen-grain,
and a larger kind, the embryo sac (Sect. 383). An impor-
tant result of heterospory is that the gametophyte becomes
extremely small, remaining partially or almost wholly en-
closed in the spore from which it is developed. This
dwarfing of the gametophyte is one of the most noteworthy
steps which mark the rise of the highest of the pterido-
phytes and the seed-plants from all lower spore-plants.
375. Additional Notes on the Pteridophytes. — As has
already been suggested in regard to the horsetails (Sect.
371), the pteridophytes in general are of much less impor-
tance at present than they were in earlier geological ages.1
Tree-like club-mosses were extremely abundant during the
age when most of the earth’s coal deposits were formed
(the Carboniferous Age), and a large part of the bulk of
1 See Bergen and Davis’ Principles of Botany, Chapter XXV .294
ESSENTIALS OF BOTANY
our coal is made up of the trunks and branches of these
great plants and even of their enormously abundant spores.
The leaves and stems of extinct species of ferns and
of primitive gymnospermous trees are also important con-
stituents of coal. Tree-like plants allied to the horsetails
were conspicuous features of the Carboniferous landscape,
and their remains are characteristic fossils in many coal
deposits, but they did not contribute much to the fuel
value of the deposits. Our knowledge of the luxuriant
vegetation from which coal was made has been gained from
the study of the fossil plants and parts of plants recogniz-
able in coal itself and in the rocks which lie beneath or
above it. In some instances the roots of trees are found
well preserved in underlying clays, while their trunks and
branches rise through the coal seams above. It is probable
that some coal beds have been derived from immense peat
bogs (Sect. 359).
Living pteridophytes are of little economic importance.
Many species of ferns and some of Selaginella are cultivated
for ornament. The rootstocks of one species of fern are
somewhat used in medicine, young shoots of the bracken
fern are edible, and the spores of various species of Lyco-
podium are still occasionally used by apothecaries to dust
over the surfaces of pills and for other purposes.CHAPTER XXVIII
SUMMARY OF THE HISTORY AND CHARACTERISTICS OF
THE PLANT KINGDOM1
376. The Plant World Originally Simpler. — Plants as
we see them about us to-day are of all degrees of size and
complexity from bacteria to the highest seed-plants. How-
ever, it would be a serious mistake to think of the plant
kingdom as always having been as complex as this, or to
suppose that the plants which now coexist have always
coexisted. Any one looking over the surface exposed in a
gravel-pit may perhaps find a stone spear-head made hun-
dreds of years ago (and of a pattern thousands of years old)
beside a cartridge shell of last year’s model. But unnum-
bered generations of men flourished and died between the
period of the first spear-head and that of the first metallic
cartridge, and both kinds of objects have never been manu-
factured in any region at the same time.
The exact time at which plant life first made its appear-
ance on the earth is unknown; — it must at least have been
many millions of years ago.2 The precise kind or kinds
of plants which first appeared cannot now be determined.
1	A large library of books on the topics outlined in this chapter could easily
be accumulated. Some important titles may here be referred to by their num-
bers as given in the bibliography of Bergen and Davis’ Laboratory and Field
Manual of Botany, — see numbers 1, 3, 36, 37, 66-70.
2	In such a brief and elementary presentation of plant evolution as is given
in the present chapter conclusions must be stated without much attempt to
show the process of reasoning upon which they are based.
295296
ESSENTIALS OF BOTANY
It is fairly certain that they were of the simplest structure,
probably far below any of the more highly developed algae.
377. The Earliest Plants akin to Animals. — It is easy
in the case of the higher members of both kingdoms to
state the differences between plants and animals. No one
can fail to distinguish between the grazing animal and the
grass on which it feeds.
Most Animals	Most Plants1
1. Obtain carbon from carbohy- drates or oil made by plants or other animals.	Obtain carbon from carbon di- oxide in air or water.
2. Obtain nitrogen from proteids and so on.	Obtain nitrogen from nitrates in soil.
3. Have no chlorophyll.	Have chlorophyll.
i. Have not cell-walls of cellulose.	Have cell-walls of cellulose.
5. Have great division of labor among the cells.	Have little division of laboramong the cells.
6. Are mainly consumers of food and use much of the energy derived from their food in locomotion.	Are mainly producers of food and use little or no energy in locomotion.
There are many exceptions to the statements above
given; as, for instance, fungi fail to conform to the char-
acteristics given under the headings 1, 2, 3, and 6. Some
of the lowest known organisms, such as the slime-molds
1 See Thomson’s Outlines of Zoology, Chapter II, D. Appleton & Co.,
New York.HISTORY OF THE PLANT KINGDOM
297
(Fig. 214) and the flagellates,1 have so many characteris-
tics common to plants and animals that they are described
both in botanies and zoologies, are spoken of now as plants,
now as animals, and really
belong to a borderland be-
tween the animal and the
plant kingdom. Flagel-
lates frequently have the
animal characteristic of
taking particles of solid
food through a funnel-
like depression, and they
resemble animals in their
power of swimming freely
about. Some of them re-
semble plants in their
possession of chlorophyll
and power of using carbon
dioxide in photosynthesis.
We cannot say that the
plants of higher organiza-
tion are descended from
such forms as the slime-
molds and the flagellates.
But since these constitute
a kind of link between ani-
mals and plants and are
of simpler structure than
most other living beings, it is not improbable that all
living organisms are the modified offspring of lowly forms
not unlike those of Fig. 214. A more immediate ancestor
1 Bergen and Davis’ Principles of Botany, Sect. 201.
Fig. 214. Slime-Molds.
B
(x 350-390.)
A, spores, two of them germinating; B,
swarm-spores; C, creeping, animal-like
{amcebiform) condition; JD, naked mass
of protoplasm (plasmocUum) produced
by the union of many individuals like C.298
ESSENTIALS OF BOTANY
of the higher green plants is probably to be found among
the remarkable group of algae (Volvocacece) to which Volvox,
JPleoclorina (Fig. 215), and similar colonial forms belong.
378. Remains of the Earliest Plants
not Preserved. — The rocks in many
parts of the earth’s crust contain fossil
remains of plants, often in enormous
numbers (Sects. 303, 375). But we
may fairly suppose that none of the
earliest plants are thus preserved, on
account of their soft and perishable
nature. This must have made it diffi-
cult for them to leave impressions in
beds of mud or sand, or for them
to last long enough to let limestone
or other substances gradually become
j? ig. zio. neoaonna, a	c
Colonial Green Alga. deposited, instead of the material of
A, a cell-colony (magnified) the Plant- Since the first plants were
swimming by means of swept out of existence ages ago, our
shown by the arrow; B, knowledge of their form, structure,
one of the smaller cells ant[ relationships to later plants must
(much magnified), show- .	.	.	..	..	.
i„g the loDg cilia c, the be drawn trom studies of the types
eye-spot e (supposed to which we know, either in the shape
be sensitive to light), the . .	.	.	1
nucleus n, the pyrenoid 01 IOSSlls Or as living* Species.
p< and the cup-shaped 379. Evidence from the Life His-
chloroplast cl.
tories of Plants. — Every individual,
seed-plant and every one of the higher spore-plants during
its life history goes through a series of changes, — from the
spore with which it begins to the most highly developed
form of which that plant is capable. This gradual unfold-
ing of organs, from a very simple spore as the starting
point, means everything to the botanist. For in botany,HISTORY OF THE PLANT KINGDOM
299
as in zoology, it is a well-recognized law that the develop-
ment of every individual usually follows in outline the course
of development of its group. During the process of hatch-
ing, while the young animal in the egg is beginning to
develop into a turtle, an alligator, or a bird, the general
form of the embryo is for some time much the same in
all three cases. It is probable that this arises from the
fact that turtles, alligators, and birds have sprung from
a common ancestor, — an animal which lived in the far
remote past and which united in its organization some of
the characteristics of these its descendants.
Reasoning in this same way, we may, for example, feel
sure from the resemblance in essentials between the pro-
thallia of ferns and horsetails that these two kinds of
plants, so different in the general form and structure of
the full-grown sporophytes, have a common ancestiy.
This is only one rather simple instance, out of many,
of likeness in the early stages in the life history of two
classes of plants which are most unlike in their adult con-
dition. By comparing in this way the successive steps in
the development of great numbers of plants of different
groups, it has become possible to draw up a sort of pedi-
gree of the plant world. This is not as yet by any means
complete, but what is already known on the subject throws
much light on the reasons for the existence of structures
in the early part of the life histories of many plants which
would otherwise seem to be wholly useless and without
meaning.1
380. Plants form an Ascending Series. — All modern
systems of classification group plants in such a way as
to show a succession of steps, often irregular and broken,
1 See Bergen and Davis’ Principles of Botany, pp. 243, 273, 404, 405.300
ESSENTIALS OF BOTANY
seldom leading straight upward, from very simple forms
to complex ones. The humblest thallophytes are merely
single cells of microscopic size. Class after class shows
an increase in complexity of structure and of function
until the most perfectly organized plants are met with
among the dicotyledonous angiosperms. During the lat-
ter half of the nineteenth century it first became evident
to botanists that among plants deep-seated resemblances
imply actual relationship, the plants which resemble each
other most are most closely akin by descent, and (if it were
not for the fact that countless forms of plant life have wholly
disappeared) the whole plant kingdom might have the rela-
tionships of its members ivorleed oat by a sufficiently care-
ful study of the life histories of individual plants and the
likenesses and differences of the several groups which make
up the system of classification.
381. Development of the Plant from the Spore in Green
Algae and Mosses. — The course which the forms of plant
life have followed in their successive appearances on the
earth may be traced by the application of the principle
stated in Sect. 379.
Such algae as the pond-scums produce spores which give
rise directly to plants like the parent.
A moss-spore in germination produces a thread-like pro-
tonema which appears very similar to algfe of the pond-
scum sort. This at length develops into a plant with
stem and leaves, — the sexual generation of the moss.
The fertilized archegonium matures into a sporophyte
which is the alternate non-sexual generation. This is
attached to the moss-plant or gametophyte, but is an im-
portant new organism. In the moss the sexual generation
is the larger and more complex of the two, the non-sexualHISTORY OF THE PLANT KINGDOM
301
generation being smaller and wholly dependent for its food
supply on the other generation to which it is attached.
382. Development of the Plant from
the Spore in Pteridophytes. — In the f
pteridophytes there is an alternation of
generations, but here the proportions
are reversed, the prothallium, or sexual
generation, or gametophyte, being usu-
ally short-lived and small (sometimes
microscopic), and the non-sexual gen-
eration, the sporophyte, often being
of large size. The ferns (non-sexual
generation), for instance, are peren-
nial plants, some of them tree-like.
Some pteridophytes, as the Salvinia, a
small, floating aquatic plant sometimes
known as a water-fern (Fig. 216), pro-
duce two kinds of spores, the large ones j-IG 2\g. a Water-
known as megaspores, and the small Fern (Salvinia).
ones as microspores (Fig. 217). Both /, floating leaves; r, sub-
kinds produce mersed leaves> actin?
A e	as roots; s, spore-fruits,
microscopic
prothallia, those of the former bear-
ing only archegonia, those of the
latter only antheridia. From the
prothallia of the megaspores a plant
Fig. 217. Two Indusia of (non-sexual generation) of consid-
Salvinia.	erable complexity of structure is
mi, microspores; ma, mega- formed.
spores'	383. Parts of the Flower which
correspond to Spores. — In seed-plants the spore-formation
of spore-plants is represented, though in a way not at all302
ESSENTIALS OF BOTANY
evident without careful examination. The pistil is the
megaspore-producing leaf, or megasporophyll, and the sta-
men is the microspore-producing leaf, ot microsporophyll.
Pines and other gymnosperms produce a large cell (the em-
bryo sac) in the ovule (Fig. 218)
which is the megaspore, and a
pollen grain which is the micro-
spore. In its development the
megaspore produces an endo-
sperm or small cellular prothal-
lium, concealed in the ovule. The
microspore contains vestiges of a
minute prothallium.
In the angiosperms the mega-
spore and its prothallium are still
less developed, and the micro-
spore, or pollen grain, has lost
all traces of a prothallium and
is merely ail antheridium which
sooner or later produces two
generative cells. These are most
easily seen in the pollen grain,
but sometimes they are plainly
visible in the pollen tube (Fig.
128, B).
Seed-plants are distinguished
from all other plants by their
power of producing seeds, or enclosed imgaxporangiu with
embryos.
384. The Sexual Generation and Relationships of the
Great Groups of Plants. — On summing up Sects. 381—
383 it is evident that the sexual generation in general
Pig. 218. Longitudinal Section
through Fertilized Ovule of a
Spruce.
p, pollen grains; t, pollen tubes;
n, neck of the arckegonium;
a, body of archegonium with
nucleus; e, embryo sac filled
with endosperm.HISTORY OF THE PLANT KINGDOM
303
occupies a less and less important share in the life of the
plant as one goes higher in the scale of plant life.1 In
the case of the rockweed, for instance, the sexual genera-
tion is the plant. Among mosses the sexual generation is
still very prominent in the life of the plant. Ordinary
ferns show us the sexual generation existing only as a
tiny independent organism, living on food materials which
it derives from the earth and air. In the Salvinia it is
reduced to microscopic size and is wholly dependent on
the parent plant for support. Among seed-plants the
sexual generation is so short-lived, so microscopic, and so
largely enclosed by the tissues of the flower that it is
comparatively hard to demonstrate that it exists.
The fact that the life history of so many of the classes
of plants embraces a sexual stage, in which an egg-cell is
fertilized by some sort of specialized cell produced wholly
for use in fertilization, tends strongly to show the common
origin of the plants of all such classes. We have reason
to believe, from the evidence afforded by fossils, that plants
which have only a sexual generation are among the oldest
on the earth. It is therefore likely that those plants which
spend the least portion of their entire life in the sexual
condition were among the latest to appear. Then, too,
those which have the least developed sexual generation
are among the latest of plants. Judged by these tests,
the angiosperms must be the most recently developed of
all plants.
If one were to attempt to arrange all the classes of ex-
isting plants in a sort of branching series, to show the way
in which the higher plants have actually descended from
1 A good many plants of low organization, however, are not known to pass
through any sexual stage.304
ESSENTIALS OF BOTANY
the lower ones, he would probably put some one of the
green algae at the bottom and the angiosperms at the top
of the series.
385.	The Oldest Angiosperms. — It is impossible to give
an}r of the reasons for the statements of this section with-
out making an unduly long chapter. It is not yet certain
whether monocotyledons or dicotyledons were the first to
appear on the earth. The descent and various relation-
ships of the families of dicotyledons can be discovered by
the study of the flower, fruit, and seed better than by the
examination of the vegetative organs.
The entire pedigree of the several families cannot be
represented by arranging the names of the families in a
straight line. Their relationships can be shown, however,
in a general way, and a part of the pedigree is indicated
by the succession of families in the Flora which accom-
panies this book. The Willow family is perhaps the oldest
of the more familiar families of dicotyledons, and the Com-
posite family the youngest. The beginner must remember
that it is not such “ typical ” flowers as are shown in
Figs. 97 and 98, but rather bilaterally symmetrical ones
like Fig. 101, or epigynous and closely grouped flowers like
those of the Composite family (Appendix I, Fig. 8), that
represent the highest development among flowers.
386.	Division of Labor and Plant Evolution. — A little
has been said in Sect. 384 about the steps of development
in the reproductive processes of plants. In general the
more complicated kinds of reproduction are found among
the younger and higher types of plants. The same gen-
eral law applies to the vegetative parts of the plant body.
The lowest undoubted plants (Figs. 150,169) show very
little division of labor among their parts. A single cellHISTORY OF THE PLANT KINGDOM
305
constitutes the individual, and this cell must do all the
kinds of work of which the plant is capable; it must pho-
tosynthesize, assimilate, excrete, grow, and divide to form
new cells. There is no setting apart of
one kind of cell for vegetative work and
another kind for reproduction.
Progress toward higher types of plant
life is marked by the formation of rows
of cells with a specialized holdfast, as
in TJlothrix (Fig. 219). Another step for-
ward is marked by the appearance of
cell-division in two directions, so that the
tliallus increases in length and breadth as
in Coleochcete (Fig. 220).
Differentiation of a thallus into epider-
mis and spongy parenchyma cells within
is well shown in some of the simplest
liverworts, such as Ricciocarpus (Fig.189),
and filaments, known as rhizoids, serve to
absorb water for use in nutrition. Higher
liverworts, such as Marchantia (Figs. 190—
194), show more division of labor among
the cells of the thallus, and such liver-
worts as Frullania (Figs. 195, 19G) have Fig'~1!>'
rhizoids, stems, and two kinds of leaves (X soo.)-
besides curious pitcher-like appendages. rMzoid cell, which
387. Division of Labor among Vascular serves as a hold-
fust.
Plants. — Ascending along the succession
of classes until those of the pteridophytes or vascular spore-
plants are reached, we find at this point a marked advance
in specialization of parts. Ferns, for example, are the first
forms represented in the scheme of classification (p. 210) to306
ESSENTIALS OF BOTANY
show the differentiation of the plant body into root,1 stem,
and leaf so familiar among seed-plants. In most ferns the
aerial leaves are all nearly alike, but in some genera, as
Onoclea (Fig. 209), certain leaves of peculiar form are set
aside for spore-production. In horsetails and club-mosses
the spore-bearing leaves are quite unlike the others, and
are often grouped into flower-like clusters (Figs. 211, 213).
Fig. 220. Coleochcete, a Green Alga.
The disk-like thallus is one layer of cells thick.
The fibro-vasoular bundles of ferns contain basFfibers, sieve-
tubes, tliick-walled wood cells (tracheids), and vessels. The
leaves are well provided with stomata.
It is not necessary to go into much detail in regard
to the differentiation of parts and division of labor in
seed-plants, since these topics have already been treated
(Chapters iii-xvi). As every one knows, seed-plants have
1 Rhizoids, though they perform the functions of roots, have not their
structure.HISTORY OF THE PL A XT KINGDOM
307
usually three sets of vegetative organs, — roots, stems, and
leaves. Xot infrequently, as in the ivy (Fig. 18), some of
the roots perform the work of absorbing soil water, while
others serve to aid the plant in climbing. Some plants
produce both parasitic roots and ordinary roots for absorp-
tion of water from the soil. Stems may in the same plant
function as subterranean storehouses of reserve material
and as aerial supports for leaves (Fig. 33). In Jlyrsi-
phyllum (Fig. 37), butcher’s broom, and a good many other
plants, parts of the stem serve to support in an advan-
tageous position other flattened portions which are special-
ized for photosynthesis instead of leaves. Ordinary stems
may. as in the grapevine and the woodbine, produce special
branches (tendrils) which serve as aids in climbing, and
the hawthorn, the crab apple, and the honey locust develop
dwarf branches in the form of thorns. It is especially
worth while to call attention to the fact that in seed-plants
the variety of forms and functions of leaves on the same
plant has reached a climax. For instance, in such a plant
as the lily, the lily-of-the-valley, or the star-of-Bethlehem,
we find scale leaves, foliage leaves, bracts, perianth leaves
(often of two kinds), and sporophylls (stamens and pistils).
It is difficult or impossible for the mind to grasp the
entire set of cooperative activities which go on at every
moment during the growing season in any large and highly
organized plant. Suppiose, for example, that all the living
parts of an immense pine tree could be seen in action just
before the beginning of its period of flowering. From the
tips of the rootlets to the tips of the leaves, a hundred
and fifty feet above, many millions of cells are performing
the operations of absorbing soil water, conducting it up-
ward, manufacturing plant food by complicated chemical308
ESSENTIALS OF BOTANY
processes, and conducting it to all parts of the plant body to
maintain growth in the tissues. Some of the plant food is
carried to the rudimentary flowers to form pollen and ovules
together with the structures
which bear them. Another por-
tion of building material is later
carried to the cones of the year
before, to maintain growth in the
newly fertilized ovules.1 Still
another portion goes to the
two-year-old cones to complete
their growth. And it must be
remembered that each growing
and dividing cell is not a simple
sac, filled with formless proto-
plasm, but a very complicated
structure with many highly spe-
cialized parts.
It requires considerable knowl-
edge of chemistry to follow even
the principal steps in the trans-
formations which food materials
undergo within the plant body.
Photosynthesis apparently often
results in sugar, which is quickly
changed into starch, then back
into sugar, for transference to
more remote parts of the plant. Here again it is trans-
formed (in root, stem, or fruit) into the starch or oil which
constitute the principal reserve material of most plants.
221. Effect of Cultivation
on Root2 of Carrot.
A, root of wild carrot, animal or
biennial; B, root of same spe-
cies cultivated, biennial. The
wild form can be changed in
four generations into the culti-
vated form.
1	Fertilization in the pine occurs about thirteen months after pollination.
See Bergen and Davis’ Principles of Botany, p. ;»74.
2	This is really part root and part hypocotyl.CHAPTER XXIX
PLANT BREEDING
388.	Definition of Plant Breeding. — Plant breeding
means the intentional production and perpetuation of new
varieties of plants. As a science it is not much more than
fiftj- years old. But some plants have been cultivated for
over forty-five centuries,1 and during all that time atten-
tion has been paid to choosing and keeping up desirable
varieties of plants.
389.	Selection of. Spontaneous Varieties. — As has al-
ready been suggested (Sect. 254), plants in a state of nature
produce many varieties by ordinary variation, and they may
occasionally produce new species by mutation.
Only a very few of all the multitude of spontaneous
variations among plants are likely to be valuable to man.
An example of this is afforded by the results obtained by
the discoverer of the Concord grape. This familiar grape
was a seedling from a rather promising wild variety. The
grower of the Concord mother vine raised more than
22,000 seedlings from Concord seeds and found only 21
of these worthy of further trial. Xot one of these seed-
lings is now a well-known grape.
Cultivated plants for some reason, perhaps especially
because they are highly fed and stimulated to unusually
vigorous growth, vary more than wild individuals. Any
i See De Candolle’s Origin of Cultivated Plants, Chapter I.
309310
ESSENTIALS OF BOTANY
wheat-field will show many varieties, some better, others
poorer than the average wheat plant of the field.
Timothy is the most valuable grass for hay in the
majority of the northern states. Some of its most impor-
tant variations concern such points as these :1
(1)	Duration, whether annual or perennial.
(2)	Power to spread by branches from the base of
the stem (stolons), some plants producing 10, others 250
heads.
(3)	Relation of seed-production to leaf-production: some
plants leafy and making good pasture, but bearing little seed.
(4)	Yield: single plants sometimes produce less than \
pound of hay and others over It pounds, or more than five
times as much.
390.	Selection of Parent Plants. — For thousands of
years farmers and gardeners knew of no better way to
secure good seed than to save that which was produced by
the most promising accidental varieties. But during the
nineteenth century growers of several kinds of crops,
especially wheat and sugar-beets, hit upon a more com-
plicated and successful plan. Seed from a good many of
the most promising plants in a field is saved. This seed
is then sown in isolated ground, and the plants raised from
it are carefully tended to serve as parents for a new gener-
ation of improved plants (Sect. 394). This process carried
through several generations, with careful attention paid to
the number and characteristics of all the descendants of each
original parent, furnishes a sure means of improving the
race of plants thus treated.
391.	Results of Breeding by Selection. — Already vol-
umes have been written describing some of the most im-
1 See Bailey’s Plant Breeding, Chapter V, The Macmillan Co., New York.PLANT BREEDING
311
portant results that have been attained by plant breeders
by means of the process of continued selection outlined in
Sect. 390. In a general way it may be said that almost
any characteristic of a plant or of one of its organs may
be made to vary, often in any desired direction. Flowers
or fruits may be caused to increase in size many times
over; early or late blooming or fruiting may be secured;
greater resistance to frost, drought, insects, or parasitic
fungi may be developed; a larger per cent of starch, sugar,
or oil in given parts of the plant may be obtained at
will. Some instances of such modifications are given in
succeeding sections of this chapter, but Avorks on farm-
ing and horticulture contain thousands of examples of
the sort.
392. Sugar-Beet Breeding. — Although we are more
familiar in this country with sugar made from the sugar-
cane, the larger part of the world’s supply is manufactured
from sugar-beets. Beets of many varieties have been cul-
tivated since the sixteenth century or earlier. But it was
only as late as the middle of the nineteenth century that
scientific efforts were made by Louis Vilmorin to increase
the percentage of sugar in beets grown for sugar-making.
The sweetest roots are usually the heaviest in proportion
to their bulk,1 and therefore Vilmorin tested whole beets
or pieces cut from them by placing them in brine strong
enough to float all of the roots except those which con-
tained an unusually large per cent of sugar. These selected
beets were planted for seed and became the parents of valu-
able new races.
At present the process of producing beets of the high-
est value for the manufacture of sugar is a long and
1 That is, have the highest specific gravity.312
ESSENTIALS OF BOTANY
complicated one, consisting, as usually carried out, of the
following steps :
(1)	Planting the best seed that can be bought.
(2)	Chemically testing average samples of the roots
grown from the seed of (1) to see if they are good enough
to breed from.
(3)	Selecting the best single roots by a chemical test.
Less than one-half of one per cent of all the beets tested
pass this examination.
(4)	Planting the mother roots selected in (3) for the pro-
duction of what is called “ elite seed.”
(5)	Growing from elite seed small beets which are planted
to secure commercial seed.
It requires five years to obtain seed in large quantities
from the very few selected roots with which the process
of securing improved seed is begun.1
Some notion of the thoroughness with which European
seed-growers choose their beets may be gathered from the
fact that in 1889-1890 one of the most important firms
tested 2,782,300 roots, from which it selected only 3043
to be planted for seed production. Constant pains must
be taken in maintaining the best possible seed supply, as
the quality becomes lowered at once when the seed is grown
without special precautions. Two of the most serious
ways in which a poor stock of sugar-beets falls short are
in the low percentage of sugar and in the production of
many worthless annual plants. In central Europe the
annual individuals sometimes constitute twenty per cent
of the entire crop.
The average yield of sugar from American-grown beets
is at present twelve per cent or less. Exceptional beets
1 Sue Yearbook, United States Department of Agriculture, 1904.PLANT BREEDING
313
have been found to contain more than double this amount.
It would be impossible to produce the roots in large quan-
tities with anywhere near this percentage of sugar, but de-
cided gains may easily be secured and an increase of two
per cent in the yield would mean a gain of something like
*100,000 per year in the beet-sugar production of the
United States.
393. Corn-Breeding. — Indian corn is preeminently an
American plant, and several varieties of it were known
and valued by the Indians before the coming of the whites.
The United States at present produces about four-fifths of
the world’s corn supply, and the j’early value of the grain
alone (excluding that of the leaves and stems used for
fodder, ensilage, and so on) amounts to about a billion
dollars.
Corn breeding is directed mainly to securing some one
of these three kinds of results:
(1)	More bushels per acre.
(2)	A higher percentage of any of the principal constit-
uents of the grain (starch, proteids, or oil).
(3)	Early maturing, to secure a harvest in the northern
states where the season is too short for the larger varieties.
The choice of the best seed would certainly increase our
corn crop more than ten per cent and add over 8100,000,-
000 per year to its value.
Corn for human food should contain a high per cent
of proteids, and this can readily be secured by using seed
chosen for the purpose. Corn-oil is coming to be an im-
portant article of commerce for food and for manufactur-
ing purposes. The proportion of oil in the grain has been
more than doubled by corn-breeders using seed selected
for its high oil contents.314
ESSENTIALS OF BOTANY
Corn of the South and the Middle West, growing
sometimes to a height of from fifteen to twenty or more
feet, requires nearly or quite six months to mature, but
the less prolific two- or three-foot kinds grown in the
northern United States and Canada mature in less than
three months.
394. Wheat-Breeding. — Wheat is the most important
grain for human food in temperate climates, and North
America is by far the greatest wheat-producing region in
the world. The annual value of the crop of the United
States ranges from #250,000,000 to #500,000,000. Wheat
has been cultivated for so many thousands of years that its
origin is not perfectly known. Scientific wheat-breeding,
however, began hardly a century ago and has progressed
more in the United States since 1890 than during all our
previous history.
Some desirable qualities to be sought for in wheat-
breeding are :
(1)	Large yield per acre.
(2)	Good quality for bread-making, requiring a high per
■cent of the tenacious gluten, the main proteid portion of
the grain.
(3)	Hardiness, shown in resisting severe winter con-
ditions.
(4)	Resistance to rust.
(5)	Resistance to drought.
Not all of these qualities can be combined in the highest
degree in any one variety, and therefore every region should
grow the particular kind of wheat best suited to the local
conditions and market.
In order to show how carefully the process of wheat-
breeding is managed in our best agricultural experimentPhotographs furnished by Funk Bros. Seed Co.
Plate XII. Improvement of Corn.
The upper picture shows the effect of kiln-drying seed; the lower
picture shows the effect of cross-pollination.PLANT BREEDING
315
stations, the principal steps of the operation are here
given in the barest outline, omitting many most impor-
tant details.1
(1)	Ten thousand large, sound kernels of a single good
variety of wheat are selected, planted in hills, and each
hill numbered. About ninety-live per cent of the poorer
plants are rejected as they mature. The heads of each of
the chosen plants are put together in an envelope and
preserved. When thoroughly dry the product of each
plant is weighed, and only a few of the heaviest groups of
heads are kept for seed.
(2)	The second year about a hundred of the seeds
of each mother-plant are planted in a group to which is
given a special designating number (hundred-group or
centgener). Heads of several of the best plants in each
hundred-group are reserved for seed. The total produced
by each hundred-group is weighed to enable the experi-
menter to estimate the comparative value of the mother-
plants of (1).
(3)	The third year the process gone through in the
second year is repeated.
(4)	The fourth year the same process is repeated.
(5)	The fifth year the most promising varieties are
planted in small fields in the ordinary way. Those varie-
ties which yield abundantly in the field and turn out well
in the milling tests applied to the harvested grain are
distributed among farmers for seed-wheat.
A new variety can soon be introduced over an immense
territory. It is estimated that in fifteen years from the
1 See University of Minnesota, Agricultural Experiment Station, Bulletin
No. 62; and United States Department of Agriculture, Division of Vegetable
Physiology and Pathology, Bulletin No. 29.316
ESSENTIALS OF BOTANY
time of planting one seed its descendants might be made
to cover more than 5,000,000 acres of wheat-fields.
Wheat-breeding is still making such rapid progress that
it is not now possible to say how much the quality and
quantity of our wheat crop may yet be improved by the
introduction of better varieties. The total number of
acres in the United States differs considerably from year
to year. It seems likely, as a rule, to exceed 45,000,000
acres. The average yield ranges between ten and fifteen
bushels per acre, although it is possible with the most
improved seed on the best soils to raise more than forty
bushels per acre. Choice of the best seed would undoubt-
edly increase the average yield to from thirteen to eighteen
bushels. It is easy to see how important a gain this would
be, even if the price of wheat were no more than seventy
cents per bushel.
395. Hybridizing. — Hybridizing, as the term is now
generally used, means the production of seed by the action
of pollen of one variety or species on the pistil of another
variety or species. Nearly always both species must at
least belong to the same genus in order to produce seed
that will grow, and often different species of the same
genus cannot be made to hybridize so as to secure good
seed. The offspring produced by hybridization are known
as hybrids.
It has long been known that hybrid plants are often
extraordinarily variable, but the law which governs their
characteristics (in many though not in nearly all cases)
was not discovered until 1865.1
Recently much use has been made of hybridizing in
order to set plants to varying, and the most desirable
1 See Bailey’s Plant Breeding, Chapter IV, The Macmillan Company.PLANT BREEDING
317
varieties thus produced have been selected and bred from,
as described in Sects. 392, 394.
396. How Hybrids are Artificially Produced. — Hybridiz-
ing, or crossing, plants is sometimes an easy, sometimes a
rather difficult, process. It is simplest in unisexual flowers,
for example, in those of Indian corn. Here the “tassel”
is a cluster of spikes of staminate flowers and the “ ear ”
is a spike of pistillate flowers, each thread of the “ silk ”
representing a stigma and style attached to an ovary (grain
of corn). In hybridizing corn it is only necessary to tie
a paper bag over the ear before the silk appears, in order
to keep off stray pollen, leave it covered until full grown,
then remove the bag, dust the silk thoroughly with pollen
from tassels of another variety of corn, and keep the ear
covered until the silk is entirely withered.
In most cases of hybridizing it is necessary to go through
with about the following process:
(1) Select the flower to be pollinated, before it opens
or its own pollen is mature. If it is one of a cluster of
B
Fig. 222. A Peach Flower prepared
for Hybridization.
A, flower cut round for removal of the
stamens; B, longitudinal section of a
flower showing level a, at which the
cross-section was made in A.318
ESSENTIALS OF BOTANY
flowers, as in the wheat or the apple, remove from the
cluster all the flowers that are not to be operated on.
(2)	Open the flower and remove the stamens by taking
hold of the filaments with fine forceps, or cut away all
the stamens at once, as shown in Fig. 222. Then cover
the flower or the entire twig with a paper bag until the
stigma is mature.
(3)	Pollinate the stigma with the desired kind of pollen.
This may be done with the finger tip, with a camel’s-hair
brush, or other implement. It is safer to take pollen from
a flower that has been kept covered with a paper bag, to
keep off foreign pollen.
(4)	Cover the pollinated flower again with a paper bag
until the fruit has grown considerably.
397. General Results of Hybridizing. — As already men-
tioned (Sect. 395), hybrids are likely to be extremely vari-
able. Not only may they differ from either parent, but they
may also be unlike each other. The differences include
such features as the form, size, and other characteristics of
the entire plant or of its roots, stems, leaves, flowers, fruit,
and seeds.
It is much easier to perpetuate new varieties in the case
of plants propagated by vegetative means than in those
grown from seed. If a desirable variety of potato is ob-
tained by hybridizing and then planting seeds from the
berries (“ potato balls ”), the hybrid can be grown with
certainty by planting tubers of the new variety. But if a
hybrid bean, pea, or wheat plant is produced, only a few
of its seeds will “come true to seed”; that is, the off-
spring of the hybrid seeds will, many of them, be what
breeders call “ rogues,” or undesirable varieties, not closely
resembling their hybrid parent. Year after year, for severalPLANT BREEDING
319
generations, the garden-plots containing descendants of
the new hybrid must be rogued, or gone over plant by
plant, in order to destroy all individuals but those of the
desired variety. In the case of wheat, after the fourth
generation some plants are usually to be found that will
“ come true to seed.”
398. Results of Hybridizing the Grains. — In this coun-
try especial attention has been given to hybridizing In-
dian corn and wheat. Some valuable varieties of corn have
already thus been obtained and many more seem likely to
a, a stoneless wild plum ; b, c, cl, fruit of hybrids of a with the French
prune. (All drawn to the same scale.)
be secured. Hybrid wheats are of importance for use as
stocks from which to breed and select. Much time is now
spent at the agricultural experiment stations of the great
wheat-growing states in hybridizing wheats for breeding
purposes.
399. Results of Hybridizing Small Fruits. — The most
familiar hybrids among small fruits are grapes. Very
likely the Delaware and the Catawba are hybrids, and the
Salem, Brighton, and Diamond certainly are. Many varie-
ties are directly or remotely descended from hybrids be-
tween the European wine grape and our northern fox
grape, two wholly distinct species.320
ESSENTIALS OF BOTANY
A favorite blackberry, the Wilson Early, is a hybrid be-
tween two common wild species, the high blackberry1 and
the dewberry.2 Among
the descendants of hy-
brids between an almost
uneatable species3 from
Siberia and an eatable
species4 from California
is a new constant spe-
cies (not a variety), the
Primus blackberry.
Hybrid plums in the
greatest variety have
been produced by plant
breeders, especially by
the well-known Cali-
fornian experimenter,
Luther Burbank. The
amount of variation in
the offspring of a single
hybrid is well shown by
Fig. 223. One fruit of
great value, the Climax
plum, was bred by this
experimenter as a hybrid
between a bitter, tomato-
shaped Chinese plum
and a Japanese plum.
400. Results of Hybridizing Citrous Fruits.— Most valua-
ble and interesting work in hybridizing plants of the Orange
family has been done by the United States Department of
1 Rubus allegheniensis. 2 R. villosus. 8 R. a'atsegifolius. * R. vitifolius.
Fig. 224.
A, the tangelo, a hybrid between the tan-
gerine and the grape-fruit; B, the grape-
fruit (one parent of A).PLANT BREEDING
321
Agriculture, under the direction of Dr. H. J. Webber.1
The hardy trifoliate orange, which resists our winters as
far north as Philadelphia, but bears a small, bitter, worth-
less fruit, was hybridized with the common sweet orange.
Three valuable hardy hybrids known as citranges were pro-
duced. One of them makes a good substitute for grape-
fruit, another for lemons, and the third for rather sour
oranges. They may be grown from two hundred to four
hundred miles farther north than ordinary oranges.
Another citrous hybrid is that between the tangerine
and the grape-fruit. This is called the tangelo (Fig. 224)
and has characteristics somewhat intermediate between
those of the parent species. It is smaller in size, and the
pulp is less bitter and acid than that of the grape-fruit,
while the “ kid-glove ” skin, readily peeled off with the
fingers, is like that of the tangerine.
401.	Results of Hybridizing Ornamental Flowers. — Some
of the most showy flowers of our gardens and greenhouses
are hybrids. Among the most important examples are the
genera Canna, Amaryllis, and Gladiolus. Orchids, too, have
been hybridized to such an extent that a dictionary of hy-
brid orchids has been prepared.
In most cases of flowers which have been bred and
hybridized for many years the process of improvement has
been due partly to crossing and partly to selection. It is
often impossible, to find, out how many parent species or
varieties have entered into the production of the final
hybrid.
402.	Summary of Methods and Results. — Successful
plant breeding requires a continuous effort to get better
plants, either by picking out and growing chance varieties,
1 See Yearbook of the Department of Agriculture, 1904.322
ESSENTIALS OF BOTANY
or by continued selection first of a set of choice parent
plants, then of their best offspring, and so on for several
generations.
Hybridizing sometimes (but not nearly always) aids the
plant breeder by giving him a large number of marked
variations from which
to select.
High cultivation
together with plant
breeding have brought
about many astonish-
ing results. Plums
three inches long have
recently been produced.
A hybrid beach-plum
bears so abundantly
that the twigs are liter-
ally hidden by the fruit.
The largest cultivated
apples are many hun-
dred times the bulk of
their remote wild an-
cestors. A new variety
of blackberry plant covers one hundred and fifty square
feet of soil and bears a bushel or more of fruit. Most culti-
vated roots and tubers have been greatly changed from
their wild condition, losing in the proportion of woody
fiber which they contain and gaining immensely in size
(Fig. 221).
One of the most important problems for the plant
breeder is how to secure varieties immune to diseases.
Two of the most notable achievements of our Department
Fig. 225. Effect of Cultivation upon the
Size of Apples.
The Bismarck apple, with a, the wild Asiatic
crab apple (Pyrus baccata), and b, the Euro-
pean wild apple (P. malus). (All half nat-
ural size.)PLAXT BREEDING
323
of Agriculture in this direction have been the production
of a disease-resisting variety of Sea Island cotton and of
watermelons. The soil of valuable cotton plantations had
become infested with a fungus (.Fusarium), which attacked
the roots of the plants, plugged the vessels with its hyphse,
and destroyed almost the entire crop. In consequence of
this many planters gave up cotton-growing. Observation
showed that often in a field where nearly all the plants
were killed here and there an individual survived, blos-
somed, and ripened its capsules. For four years plants
were bred from the seeds of these resistant individuals
until a variety was secured which withstood the attacks
of the fungus and made it possible to resume cotton-
growing on the abandoned plantations.
Extensive areas in the South, once devoted to the culture
of watermelons, became so infected by a fungus (Fusarium)
that melon-growing was no longer possible. The destruc-
tion was so complete that no process of selection could be
adopted, as in the case of the cotton. It was, however,
found that the roots of the so-called “ citron,” a plant of
the watermelon genus, were not attacked by the fungus.
Watermelons were, hybridized with “ citrons,” and about
a thousand varieties were grown from the seeds thus ob-
tained. Many of these proved resistant, but ordy one was
found to be resistant and at the same time desirable in
most other respects. This one variety is now grown with
perfect success on any fungus-infected soil.CHAPTER XXX
SOME USEFUL PLANTS
403.	Definition of Economic Botany; Subdivisions. —
Economic botany treats of the uses of plants to man. Be-
ginners in botany can only afford time for a brief summary
of the principal uses of a few of the most important plants.
Some of the principal classes of plant products valuable
to the human race are these :
(1)	Foods for man.
(2)	Medicinal plants and their products.
(3)	Foods for domestic animals.
(4)	Fertilizers of vegetable origin.
(5)	Tanning materials, dyes, varnishes, and miscella-
neous products of vegetable origin.
(6)	Plant fibers, hairs, and similar products.
(7)	Plants cultivated for ornament.
(8)	1 Timber and cabinet woods.
(9)	1 Fuel.
(1) FOODS FOR MAN
404.	The grains constitute the main part of our food
supply, from vegetable sources, and are especially valuable
on account of their concentrated character and their keep-
ing qualities. The principal grains are wheat, oats, rye,
barley, rice, and Indian corn. They are all the fruits of
1 These two classes are for convenience treated in Chapter XXXI.
324SOME USEFUL PLANTS
325
certain grasses known as cereals, and on account of this
and other facts the Grass family is the most important
family of plants from the economic point of Yiew. Wheat
is the most highly prized of the grains on account of
its high food value, digestibility, and fitness for bread-
making. The United States is the leading wheat- and
corn-growing country, producing more than one-fourth of
the world’s crop of the former grain and four-fifths of
the latter.
Rice is extensively grown in South Carolina and the
Gulf States, but the world’s principal supply comes from
Asia. It differs from the other cereals in requiring to be
cultivated on land that can be flooded during part of the
year. For this reason rice culture is often attended by
malaria.
405.	Leguminous Seeds. — The Pea family (Leguminosa:)
comprises about seven thousand species, and many seeds
which form a considerable part of human food are derived
from this family. The ones most generally used in our
own country are peas and beans. Whether eaten in an
unripe condition or after becoming mature and dry, they
form a highly valuable source of proteid food. Peanuts
are the seeds of a leguminous plant largely grown in the
South Atlantic States and elsewhere. Our crop of these
is largely consumed at home, but also forms a consider-
able article of export. Other leguminous seeds much used
as articles of food in Europe and elsewhere, although not
as yet largely consumed in the United States, are broad
beans or Windsor beans, chick peas, and lentils.
406.	Other Seeds. —A great number of seeds which do
not come from plants of the Grass family or the Pea fam-
ily -are used as human food. The most important tropical326
ESSENTIALS OF BOTANY
one is the cocoanut (Fig. 226), a drupe containing an enor-
mous‘seed with oily endosperm, eaten in its natural con-
dition, and also used in the preparation of many well-known
dishes and in confectionery.
Chocolate, so well known as a food, a flavoring, and
as a beverage, is made from the ground or crushed seeds
of the cacao tree (Fig. 227), cultivated
in many tropical countries, originally
a native of Mexico. Cocoa is merely
chocolate deprived of a large part of
its oily material.
Coffee, which has little value as a
food, but is most widely used as a stim-
ulating beverage, is made from the seeds
of a small tree, a native of the moun-
tains of eastern Africa, much cultivated
in tropical countries. The seeds are
borne in red berries abundantly clus-
tered in the axils of the leaves(Fig. 228).
Many edible nuts of temperate cli-
mates are furnished by three families
of trees. The Walnut family furnishes
the so-called English walnuts, black
walnuts, butternuts, pecans, and hick-
ory nuts; the Birch family furnishes
hazelnuts and filberts; and the Beech
family furnishes beechnuts and chestnuts.
From the Rose family come almonds, which are drupes,
like a peach, but with the ripened ovary-wall fibrous rather
than fleshy.
From a tropical family related to the mangroves and the
myrtles are obtained the well-known Brazil nuts.
Fig. 226. A Cluster of
Cocoanuts. (Much
reduced.)SOME USEFUL PLANTS
327
407. Pulpy Fruits. — The most important tropical fruit
with fleshy pulp is the date (botanically speaking, a berry).
The flowers (and therefore the fruits) spring directly from the main stem
and the larger branches.
This is one of the most considerable articles of food for
the peoples of northern Africa and northwestern Asia.
The date-palm is very productive, bearing for a century328
ESSENTIALS OF BOTANY
or more, and when well grown producing from one hun-
dred to five hundred pounds of fruit a year. Successful
attempts are now under way to introduce date culture
into some of the hottest portions of the United States,
and it is likely to be an important industry in central
Arizona, the Colorado Desert in
California, and several other arid
or semi-arid areas.
The Pineapple family furnishes
only one valuable fruit, the pine-
apple, grown especially in Florida,
the West Indies, the Azores, and
Hawaii.
The Banana family furnishes, in
the shape of bananas, the main food
of multitudes of the poorer inhab-
itants of the tropics. The plant
is herbaceous, though it sometimes
reaches a height of forty feet, with
leaves as much as ten feet long
(Plate XIII). The familiar fruit
(technically, a berry) has by long
cultivation become seedless. It has
a much higher nutritive value than
most fruits and is rapidly coming
imports into the United States hav-
into favor among us, the annual
ing increased from about 500,000 bunches in 1872 to some
40,000,000 bunches at present. A few bananas are grown
in southern Florida and the delta portion of the Mississippi,
but the main product comes from the West Indies and
Central America.Photograph furnished by the United Fruit Co.
Plate XIII. Bruiting Banana Plants.SOME USEFUL PLANTS
329
The Mulberry family produces the breadfruit, which is
the chief means of subsistence of many islanders of the
South Pacific. The only two fruits of the family familiar
to us are the mulberry and the fig. Our supply of figs
is mainly derived from imports of the dried fruit from
Asia Minor, but fig culture is now well established in
California.
The Saxifrage family and the Rose family produce many
of our berries, properly so called, and a number of other
kinds of fruits commonly though incorrectly known as
berries. To the former family belong currants and goose-
berries, to the latter, quinces, pears, apples, strawberries,
blackberries, raspberries, plums, cherries, peaches, apricots,
and nectarines.
Stra'wberry-growing in the T’nited States was an in-
dustry of no importance until after 1840, but has now
become extensive. The crop is a very profitable one, as
under the most favorable circumstances more than four
hundred bushels have been raised on an acre. The mar-
ket was formerly only for a few weeks of the year, but
now lasts over as much as five months, beginning in Feb-
ruary with berries from the Gulf States and ending in
July with Canadian berries.
Apples form the leading fruit crop of North America,
as the product of a good year amounts to about 100,000,-
000 barrels, for the Fnited States and Canada. They suc-
ceed well in most of the more northerly states, and about
a thousand varieties are grown.
The Rue family gives us the citrous fruits, including
ordinary oranges, tangerines and mandarins, lemons, and
grape-fruit. Oranges are of Asiatic origin and have long
been cultivated in hot and warm temperate climates. The330
ESSENTIALS OF BOTANY
first sweet oranges grown in what is now United States
territory were brought to California by the Franciscans
about 1769. Orange production in this country was for
a time most extensively carried on in Florida, but severe
frosts there cut off many orchards, and now the greater
part of the crop (over 10,000,000 boxes) comes from Cali-
fornia. The famous Washington navel orange, nearly or
quite seedless, so largely grown in California, originated
from chance seedlings. These were found growing wild
in a swamp along the Amazon, and were brought from
Bahia, Brazil, to the United States Department of Agri-
culture in the early seventies.
The Grape or Vine family contains only one genus, the
grape, which is of economic importance, but it is one of
the oldest cultivated plants. The grapes of the European
type, such as the Malaga, Black Hamburg, Muscat, and
the Tokay variety so extensively grown in California, are
solid-meated and are all descendants of a single wild spe-
cies. American varieties, such as the Concord, Delaware,
Isabella, Niagara, and many other familiar kinds, with
soft pulp readily separated from the skin, are descended
from wild American species (Sect. 389). Grape culture is
carried on most extensively in California, where the fruit
is grown for table use, for wine-making, and for preserva-
tion by drying into raisins.
The Heath family produces several highly valued spe-
cies of berries. The most important are cranberries, blue-
berries, and huckleberries. Cranberries of the ordinary
large species are borne by a delicate, trailing, woody plant,
which flourishes particularly in peat-bogs all the way from
North Carolina to Minnesota and throughout a large part
of Canada. Cranberry culture is extensively carried on inSOME USEFUL PLANTS
331
Massachusetts, New Jersey, and Wisconsin, and there is a
large yield from uncultivated swamps.
Blueberries and huckleberries belong to two different
genera, but have considerable superficial resemblance.
The former berry, borne on bushes of several species, from
six inches to ten feet in height, is the more valuable and
is gathered for the market over wide areas of the northern
United States and Canada. The “heaths” or “blueberry
barrens” on which the bushes grow in great abundance
are often carefully reserved and the berries systematically
picked for shipment.
The Olive family furnishes a very important fruit, the
olive, which is considerably utilized by pickling in salt
water and serving as a relish. Olive-oil, expressed from
the fruit, is a most valuable product and is not only used
as a food throughout most civilized countries, particularly
in the Mediterranean region, but is also utilized for many
mechanical purposes and for soap-making.
The Nightshade family, which contains many poisonous
plants, yields several edible fruits. These are true berries,
though they are not commonly so called. The principal
ones are the ground-cherry or strawberry-tomato (Phymlis),
of which wild and cultivated species are used in making
preserves, the red pepper (Capsicum),1 the egg-plant, and
the tomato. The tomato was introduced into cultivation
from tropical America as a curious ornamental plant for
the garden. Its fruit was originally small, two-celled, and
watery, but by cultivation has become large, fleshy, and
several-celled. It is extensively grown for the market,
and large canning establishments in several states handle
the product of special tomato farms.
1 This is not a pulpy fruit, hut is for convenience mentioned here.332
ESSENTIALS OF BOTANY
The Gourd family furnishes many edible fruits. Of these
the pumpkin and the summer squashes are varieties of
the same species, and the large winter squashes belong to
another species of the genus Cucurbita, probably of Amer-
ican origin. The watermelon belongs to a genus (Citrul-
lus) of Asiatic origin. The muskmelons, nutmeg-melons
and other varieties, and the cucumber belong to another
genus (Cucumis), and most of our varieties are descended
from two southern Asiatic species.
408. Edible Leaves, Stems, and Roots. — Not many
kinds of food of prime importance consist of the leaves
or aerial stems of plants. The Lily family yields aspar-
agus; the Pigweed family, spinach; the Mustard family,
water-cress, cabbage, cauliflower, and Brussels sprouts;
the Parsley family, celery; and the Compositce, lettuce and
globe artichokes (Cynara).
Since the underground portions of the plant often store
up much reserve material (Sect. 76), it is evident that
bulbs, rootstocks, tubers, and roots must often be of
value as food. Only a few of the most important of these
are here mentioned. The Lily family yields onions; the
Yam family, yams ; the Pigweed family, beets; the Mus-
tard family, turnips and radishes ; the Parsley family,
carrots and parsnips; the Morning-glory family, sweet
potatoes; the Nightshade family, potatoes; and the Com-
posite, salsify and Jerusalem artichokes (Heliauthus).
The potato crop is so important that a few words may
here be said about it. The annual yield for the Lmited
States is usually over 200,000,000 bushels. Introduced
into cultivation from Peru, potatoes soon became one of
the principal foods of the cooler parts of the world. They
are particularly well suited for cultivation in regions whereSOME USEFUL PLANTS
333
the summer is short, cool, and moist, so that wheat or
Indian corn would not mature. Many varieties have been
produced by selection from seedling plants, and under the
influence of long cultivation the size of the tubers has
greatly increased and the tendency to produce seed in
the berries (commonly known as “potato balls”) has
diminished.
409.	Tea. —Tea cannot properly be called a food, since
if drunk without cream or sugar it supplies only traces of
nourishment. It is, rather, a mild stimulant, but is so com-
monly taken with food that it may be mentioned with food
products. The tea-plant is a shrub belonging to the family
Theacece, to which the familiar camellia of the greenhouses
also belongs. It is thought to occur in a wild state in
eastern India and has for ages been cultivated in India,
China, and Japan. The tea-leaves are picked several times
during the season and dried for packing and shipment.
The various colors and grades of tea depend mainly on the
maturity of the leaves and the amount of fermentation
which they are allowed to undergo before drying.
410.	Starch and Sugar.—Starch can be obtained on a
large scale from any of the grains by grinding them into
flour or meal, treating this with sulphurous acid or alkaline
solutions in order to get rid of the sticky proteid material
which holds the starch grains together, and then washing
the starch out clean from the bran and other impurities
with which it is mixed. Corn-starch, for use as food, is
extensively manufactured in this country.
Sago is the purified starchy pith of sago-palms, small
trees found in Siam and the Malayan Islands. It is also
made from palm-like plants (cycads), natives of the West
Indies.384
ESSENTIALS OF BOTANY
Tapioca consists mainly of starch. It is made from the
grated or ground-up roots of the cassava plant (Fig. 229),
a native of Brazil, now cultivated in many of the warmer
parts of the world, including our own Gulf States. The
clustered roots may together weigh as much as thirty
pounds, and the product per acre is therefore very large.
The juice of one species is acrid and poisonous, but is
Fig. 229. A Twig and Cluster of Roots of Cassava. (Mucli reduced.)
soon removed by heating or merely drying the ground
roots, which form an extremely valuable food for horses,
cattle, and hogs.
Arrowroot is a highly digestible kind of starch obtained
from the rootstocks of several kinds of tropical plants of
the Arrowroot family (Mnrantacen) and other families.
Sugar is manufactured from the juice of the sugar-cane
(Fig. 230), a grass growing to the height of ten feet or
more, cultivated in Louisiana, the West Indies, Java, andSOME USEFUL PLANTS
335
the Hawaiian Islands. It is also still more largely manu-
factured from the juice of the sugar-beet (Sect. 392), both
in Europe and in our own country.
A small amount of sugar of delicious flavor is made in
various parts of the United States
from the sap of the sugar maple.
(2) MEDICINAL PLANTS AND
TIIEIR PRODUCTS
411. For thousands of years
nearly all the most important
medicinal substances were parts
of plants or simple infusions
(“ teas ”) or tinctures made from
plants. During the nineteenth
century chemical compounds,
such as the alkaloids, of which
quinia and morphia are familiar
examples, took the place, to a con-
siderable extent, of cruder prepa-
rations, such as wine of Peruvian
bark and laudanum, made from
the same plant material. More
recently many of the coal-tar prod-
ucts have come into general use
as remedies. But a little exami- Fig. 23°- Flower Cluster
nation of the contents of any well- (Huch reduced.)
stocked pharmacy will serve to
show how dependent we still are on the curative action of
plants for treating diseases. Sometimes the dried root,
stem, or leaf is sold for medicinal use, as in the case of
marshmallow root, quassia wood, sage leaves. Often the336
ESSENTIALS OF BOTANY
fruit, as in the so-called cardamom seeds, or the seed, as in
mustard and flaxseed, is the medicinal part of the plant.
Occasionally some secretion or excretion of the plant is of
remedial value, as in the case of Canada balsam and gum
arabic. Nearly seventy families of angiosperms are repre-
sented in the official list of medical plants.-1 Some fam-
ilies have medicinal properties quite generally distributed
throughout their species, while others have only one or a
few species with curative properties.
Medical botany is a subject on which many special works
have been written, but this brief summing-up is all that
can be given here.
(3) FOODS FOR DOMESTIC ANIMALS
412. Some of the grains, especially corn, oats, and bar-
ley, are largely fed to domestic annuals. Of the roots and
tubers which are used for human food, beets, carrots, tur-
nips, and potatoes are considerably fed to cattle, sheep,
and hogs in some parts of the country.
Many of the grasses constitute pasture for grazing ani-
mals or are made into hay. Throughout a large part of the
United States the hay crop is one of the most important
of all to the farmer, and its annual value usually amounts
to over (1500,000,000. Alfalfa, several clovers, soy-beans,
and cow-peas are some of the principal plants of the Pea
family useful as horse and cattle food.
Forage is prepared from such plants as red clover, alfalfa,
and others, cut green and fed to horses and cattle. Corn-
stalks, when nearly mature, are largely used in this way,
and the stems and leaves cut up and allowed to ferment are
1 The United States Pharmacopoeia.SOME USEFUL PLANTS
337
largely used as a winter food for cattle under the name of
ensilage. Much use is also made of dried corn stems, with
the leaves, variously known as “ corn fodder ” and stover.
The residues left after certain manufacturing processes
are of great value as food for horses, cattle, sheep, or hogs.
Among these are linseed meal and cotton-seed meal from
which all the oil possible has been extracted by pressure.
Brewers’ grains and distillery swill, the latter consisting
of a sort of thin sour gruel of corn meal from which all
the alcohol has been distilled, may be fed in moderate
quantity to cattle and hogs without ill effects, and are
used in the fresh condition and dried for shipment. The
refuse from the manufacture of beet-sugar is also consider-
ably utilized, both moist and after drying.
(4) FERTILIZERS OF VEGETABLE ORIGIN
413. Crops impoverish the soil by removing from it the
raw materials for the manufacture of plant food. The
most valuable of these are nitrates and potassium com-
pounds. It is evident that the fertility of the soil can
best be maintained by restoring to it all parts of the plant
not to be sold at a profit. For instance, if beans are grown
upon a piece of ground, the stems and leaves, after the
crop has been gathered, should in some way be restored
to the soil and plowed under, — not burned, since burn-
ing would destroy much available nitrogen. Cotton-seed
meal is much used as a fertilizer and restores to the soil
most of the valuable material taken from it by the growth
of the cotton crop.
Wood-ashes is a useful fertilizer, from the amount of
potassium salts which it contains.338
ESSENTIALS OF BOTANY
Seaweeds are considerably employed for fertilizing pur-
poses along some parts of the New England coast.
It has long been known that poor soils may be bene-
fited by plowing under certain crops grown upon them.
Most of the plants employed in this way belong to the
Pea family, and clovers and alfalfa are among the species
Fig. 231. Roots of Reel Clover with Tubercles.
I, sections of ascending branches; b, enlarged base of stem; t, root-
tubercles containing bacteria.
commonly plowed under. It has only recently been ascer-
tained that the value of leguminous plants for this purpose
is chiefly due to the fact that they bear upon the roots
tubercles containing bacteria (Fig. 231) which can take
free nitrogen from the air and deliver it to the host-plant
(clover, etc.) in a form which can at once be utilized by theSOME USEFUL PLANTS
839
latter. These “ nitrogen-fixing bacteria ” therefore afford
an unlimited supply of nitrogen available for the nutrition
of the higher plants almost without expense to the farmer
and gardener.
(5) TANNING MATERIALS, DYES, VARNISHES, AND
MISCELLANEOUS PRODUCTS OF
VEGETABLE ORIGIN
414. Many of the substances mentioned under this head
are fully discussed in treatises on the chemistry of various
manufacturing industries. All that can be done in this
place is to give a few examples of plant products used in
manufacturing processes.
Vegetable dyes are no longer nearly as important as
they were before the discovery of aniline colors. Antique
Oriental rugs and other articles, however, show well how
much superior are the soft shades produced by dyes of
vegetable origin. A large number of dyestuffs are ob-
tained from tropical or sub-tropical plants of the Pea
family ; among these are Brazil wood, logwood, camwood,
and indigo.
Varnishes usually consist of some kind of rosin dis-
solved in alcohol, oil of turpentine, or linseed oil. Among
the most valuable varnishes are shellac (from trees of the
Mulberry family), copal (Pea family), and Japanese lacquer
(Sumach family).
Common rosin and turpentine are made from the sap of
pine trees, particularly our longleaf southern pine. Deep
cuts are made through the bark into the wood, and from
these a pitchy liquid slowly flows. By distilling, this
is separated into a nearly colorless liquid, oil of turpentine,
commonly called “ spirits ” of turpentine, and the familiar340
ESSENTIALS OF BOTANY
rosin used by tinners. The liquid evaporates and is con-
densed, while the rosin is left behind in the still.
Tanning is mainly done by the use of infusions of vari-
ous kinds of astringent bark. In this country the bark of
the black oak and the Spanish oak is largely used. Hem-
lock bark is also employed and is often treated in the
forests where the trees are felled, to obtain a thick ex-
tract, which is shipped in barrels to the tanneries. Twigs
and leaves of American and Sicilian sumach are used in
tanning some of the thinner and finer kinds of skins, and
imported extracts made from several tropical trees are
employed in some tanneries.
India rubber is made from the sap of several trees and
lianas found in the tropical regions of both hemispheres,
and gutta-percha is yielded by trees of the tropical Star-
apple family, which also produces many edible fruits.
(0) PLANT FIBERS, HAIRS, AND SIMILAR PRODUCTS
415. Many of the most valuable plant fibers, such as
flax and hemp, are manufactured from the hard bast,
others, as cotton, are composed of plant-hairs. Sometimes
the whole stem or leaf of the plant is braided into a fabric,
as in the case of straw hats and similar articles.
Sedges (Cypenis) are woven into East Indian and Chi-
nese mattings.
Grasses of several genera (including some of the grains)
are braided into hats, mats, baskets, and other articles.
Straw and the coarse, tough esparto grass from Spain and
North Africa are used in paper-making.
Palms yield abundant supplies of fiber, and that of the
husk of the cocoanut is used to make rope, mats, and brushes.SOME USEFUL PLANTS
341
The Banana family yields the well-known manila fiber
which is woven into very delicate fabrics, while the coarser
kinds make the tough manila rope.
The Mulberry family contains the paper mulberry tree,
from the bark of which is made Japanese paper, and the
hemp plant, of the greatest importance in the manufacture
of rope and twine.
The Linden family, the Mallow family, and the Silk-
cotton family, all closely related, are the source of many
valuable hairs and other fibers. Of these cotton, belong-
ing to the Mallow family, is by far the most important.
The product which is spun into thread and woven into so
many kinds of fabrics consists of the hairs which thickly
clothe the seeds of the plant. Cotton is cultivated in
India, Egypt, and our own Gulf States, Georgia and South
Carolina. The Sea Island cotton, grown on islands off the
coast of South Carolina, is the most valuable variety any-
where produced, on account of its length and fineness.
Our annual cotton crop amounts to from 9,000,000 to
13,000,000 bales of 500 pounds each and is of a value
ranging from over 8300,000,000 to nearly 8000,000,000.
The stems of the plant may be utilized for paper-making,
and the seeds afford a valuable meal used as a food for
cattle and a fertilizer.
Paper-making consumes immense quantities of vege-
table fibers of various kinds. Linen and cotton rags, old
hemp and manila rope, jute and even straw, are used in the
manufacture of various grades of paper. Several kinds
of the softer woods, especially spruce and poplar, are very
largely employed in making some of the poorer kinds of
white paper, such as are used for printing newspapers.342
ESSENTIALS OF BOTANY
(7) PLANTS CULTIVATED FOR ORNAMENT
416. Many thousand species of ornamental plants are
cultivated in our parks, gardens, and greenhouses.
As regards size and duration, these plants may be classed
into trees, shrubs and undershrubs, herbaceous perennials,
and annuals. A good many evergreen conifers are planted
for shade trees, but the number of hard-wood trees is still
larger- Some of the most beautiful species, like the great-
flowered magnolia, are not hardy in the northern United
States, and many considerations, such as power to resist
cold, drought, insect enemies, wind storms, and other de-
structive agencies, all have to be taken into account in
making choice of shade trees for any given locality.
Shrubs and undershrubs are cultivated for their foliage,
as the box and privet; for their flowers, as Forsythia and
lilac ; for their fruit, as mountain ash.
With the exception of foliage plants, as some cannas,
Coleus, and a small number of other common species, most
herbaceous plants are grown for their flowers.
By far the larger part of our cultivated ornamental plants
are natives of other countries, and some common weeds,
like bouncing Bet {,Saponaria) and blueweed (Echiuni), have
become introduced by cultivation. Tropical plants are of
course usually cultivated only in greenhouses, and the
list of these is a very long one, including among the rarest
and most beautiful species many of the Orchis family. Of
our native species common in cultivation perhaps the most
beautiful shrubs are several azaleas and Rhododendrons
of the Heath family, and the most showy late summer-
and autumn-blooming plants are several Compositor, such as
Rudbeckia, Coreopsis, and Helianthus (the sunflowers).CHAPTER XXXI
TIMBER; FORESTRY
417. Coniferous Woods. — Our native woods1 are best
classified into the two principal groups of soft (or conifer-
ous) and hard woods.2 The* needle-leaved or coniferous
trees of the country furnish more than three-quarters of
our timber supply. Of these trees the pines are the most
important, and there are at least eight species of them
which may be ranked as sources of timber. White pine
(.Pinus Strobus) is the softest and most workable of all,
while long-leaf pine (P. palustris. Fig. 232) is the hardest,
strongest, and most durable when exposed to the weather
or in the soil.
Of coniferous woods other than pines some of those
most in use are: in the East, two species of spruce (Picea)
and hemlock (Tsuga); in the South, the American or bald
cypress (Taxodium); in the West, species of spruce (Picea),
the smaller redwood (Sequoia), and the “ Douglas fir ”
(Pseudotsuga).
The structure of coniferous wood, as seen for example
on the end of a beam cut off squarely, or on a new lead
pencil, is in one respect less complex than that of most
1	See United States Department of Agriculture, Division of Forestry, Bulle-
tin No. 10, “ Timber.”
2	Some of the needle-leaved or coniferous trees, such as the larch and the
yew, have rather hard wood, and some broad-leaved trees, such as willows,
poplars, tulip-trees, and buckeyes, have softwood, but people who deal in tim-
ber usually speak of the two general classes as explained above.
343344
ESSENTIALS OF BOTANY
hard woods. There are no ducts, and the main bulk of
the wood is composed of rather long closed tubes (tracheids)
which taper to a point at each end. The rings plainly seen
on the cross-section of some kinds of coniferous timber are
Fig. 232. Forest of Hard or Yellow Tine (Pinus palustris) on Southern
Coastal Plain of the United States.
(After Frye.)
due to the difference in diameter of the tracheids formed
in early spring and later on (Fig. 233).
418. Hard Woods. — North America furnishes more spe-
cies of trees valuable for hard-wood timber than any other
region of similar area with a temperate climate. About
eighty kinds are of economic importance, and of these
six or eight are oaks, classed for commercial purposes as
white and red or black oaks. White oak is stronger thanTIMBER; FORESTRY
345
the red. kinds but has not so coarse a grain, so that for
cabinekmaking the red oaks are more ornamental and often
in “ quartered ” cut lumber (sawed tangentially) are very
showy. More than half of our supply
of hard-wood timber is furnished by
the oaks.
Tulip-wood, from the tulip-tree (Liri-
odendron), is next in importance to
the various kinds of oak, among the
woods of broad-leaved trees. It is va-
riously known as jrellow poplar and
white wood and grows in abundance
in the Ohio Basin and southward, but
does not, like oak, form separate for-
ests. The wood is very soft and work-
able and has largely taken the place
of white pine for the inside finish
of houses and in the manufacture of
wooden ware.
Ash, beech, birch, chestnut, elm,
maple, red gum, and sycamore are some
of the most important hard woods for
general purposes besides those already
mentioned. For especial purposes cer-
tain woods not of the greatest value
for all-round construction are highly
prized, as hickory for ax and other tool
handles and for carriage spokes; beech
for shoemakers’ lasts, saw handles, and
carpenters’ planes; persimmon for wood turning and shoe
lasts; black locust for posts and railroad ties (on account
of its durability in the ground).
Fig. 233. Cross-Section
of Fir Wood.
s, a rosin passage; m, med-
ullary rays. (Much
magnified.)346
ESSENTIALS OF BOTANY
For cabinet work the most valued of our hard woods
are black walnut, cherry, birch, and a good many spe-
cies of oak and of ash. White walnut, red or sweet
gum (Liquidambar), sycamore, and holly are also used.
Fig. 234. Hickory (Hard-Wood).Forest near Southern End of
Appalachian Highlands.
(After Frye.)
In structure the broad-leaved woods may be classed
into two groups, — the ring-porous and the diffuse-porous
kinds.
In the former most of the conspicuous ducts (the cut-off
ends of which appear as pores in the cross-section) are
found in the spring wood. In the latter the ducts are
scattered somewhat generally throughout the wood of theTIMBER; FORESTRY
347
Fig. 235. Spreading Habit of a Tree growing in the Open.
Trees standing by themselves, like this American elm, are of use for firewood
but do not furnish much valuable lumber.348
ESSENTIALS OF BOTANY
spi’ing and summer growth (Fig. 236). Among the com-
monest and most typical of the ring-porous woods are ash
and oak, and of the diffuse-porous ones, birch and maple.
419. Wood as Fuel. — Although coal (Sect. 375) is the
fuel of the world’s great industries, yet there are large
areas throughout which wood is still the principal fuel.
All kinds of wood can be burned, but for certain purposes
those kinds are preferred which make an abundant flame
or which leave solid beds of glowing coals. In general the
heating effect of well-dried wood when burned is nearly
Sycamore	Birch
Fig. 236. Diffuse-Porous Woods. (Somewhat magnified.)
cir, annual rings.
proportional to its weight per cubic foot. The fuel value
per cord is therefore dependent on the weight per cord,
and the heaviest woods, such as hickory, most of the oaks,
hackberry, and some kinds of ash, are the best for burning.
For certain purposes, where a concentrated smokeless fuel
which lights easily and does not readily go out is required,
charcoal is employed. Generally the heaviest woods make
a dense charcoal of great heating power.
420. Forestry. — Forestry as a science deals with the
factors which concern the occurrence and growth of for-
ests. Forestry as an art deals with the rules of forestTIMBER; FORESTRY
349
management and is directed toward the
maintenance of our existing forests in
the most productive condition possible
and the establishment of new areas of
woodland. Forestry has long received
much attention in most parts of cen-
tral and northern Europe, but among
us it is only beginning to assert itself as
a subject which must be taken into ac-
count to insure continued national pros-
perity. Coming to a heavily wooded
country, our early colonists felt that
the woods were their natural enemies,
hindrances to- farming operations, and
lurking places for Indians and wild
beasts. The forests were rapidly cut
down and burned, and it did not occur
to most people until this wholesale de-
struction had gone on for more than a
century and a half that our timber
lands formed one of the most impor-
tant portions of our natural resources.
421. Forest Management. — This is
too technical a subject to be treated
in any detail in a high-school botany,
though there is much of the element-
ary part of it which is quite within the
reach of high-school pupils.1 A few of
the main principles are as follows:
(1) Only mature trees should be cut,
unless saplings are needed for special
Fir;. 237. Effect of
thinning out on For-
est Growth.
The figure represents part
of the cross-section of
a fir tree, about half
natural size; the early
growth from a to b was
very slow, as the young
tree was shaded by
spruces; from b to c the
growth was more rapid,
as part of the spruces
were blown down by a
storm in 1871; from c to
fT the growth was still
more rapid, as the re-
maining spruces were
destroyed by a storm
in 1885-1886.
1 See Roth’s First Book of Forestry, Ginn & Company.350
ESSENTIALS OF BOTANY
uses, and the younger trees should not be injured by let-
ting those which are felled break them down as they fall.
Many kinds of woodland may be kept for centuries in a
condition of uninterrupted productiveness by thinning out
only the largest trees.
(2)	Forest fires must be prevented, especially in conif-
erous forests. This may be done by preventing fires from
being kindled for any purpose in large tracts of woodland,
and in some cases by cutting up woodlands, by means of
roads, into wood lots of moderate size. In dry, hot weather
constant inspection is needed to keep from spreading any
fires which may occur.
(3)	Parasitic fungi and those t^hich promptly seize upon
newly felled wood should be destroyed by^burning both
them and the infected wood, taking suitable precautions to
prevent the fire from spreading.
(4)	Destructive insects, such as the various wood-boring
and leaf-eating species, should, if possible, be destroyed.
In many cases the expense of killing the insect pests of
forests would be too great to be undertaken on a large
scale. But it is thought that sometimes this may be accom-
plished by introducing into the region affected parasitic or
other insects which will destroy the species injurious to
trees.1 Attempts are now being made to get rid in this
way of the gypsy moth, whose caterpillars strip both conif-
erous and deciduous trees until the woods attacked by
them look as if swept by fire. The importance of taking
prompt action upon the appearance of a new insect-enemy
of trees is well illustrated by the case of the gypsy moth
1 A scale insect once very destructive in Californian orange orchards was
successfully controlled by the introduction of an Australian lady-beetle which
fed on the scale insects.TIMBER; FORESTRY
351
above mentioned. It was introduced from Europe in 1869
by a scientist living at Medford, near Boston, Massachu-
setts, in the course of some experiments on silk-produc-
ing insects. It soon escaped into his garden, but could
easily have been exterminated if prompt measures had been
taken to secure every patch of eggs deposited on trees
in the vicinity. This was not done, and the insects propa-
gated themselves, until after twenty years they began to be
troublesome. In 1890 efforts to extirpate the moth were
begun on a large scale, but though from 1890 to 1897 more
than $865,000 were expended by the state in destroying the
moth, it still remained a serious enemy to the trees over a
region some two hundred-square miles in area. By the aid
of United States government funds the insect is now held in
check, but no one can say when it will be exterminated.
(5) Sheep and cattle must not be pastured in woods in
which they can seriously injure the value of the timber
product. Cattle do not usually do much damage in
forests which consist mainly of mature trees. They de-
stroy some young broad-leaved trees by browsing, but do
not molest young conifers. Sheep injure young seedling
trees by browsing, and they do much more serious damage,
particularly on hillsides and mountains, by grazing the
grass too closely and cutting the turf to pieces with their
sharp hoofs, so that it is dried up by the sun and washed
away by heavy rains. In the Rocky Mountain region and
along the Pacific slope in this country and over great
tracts in southern Europe, valuable forest land has been
converted into worthless rock and gravel-covered treeless
slopes as a result of sheep-pasturing.
422. Tree-Planting. — In those portions of the country
which are naturally forest-covered it is not usually worth352
ESSENTIALS OF BOTANY
while to start large pieces of woodland by seeding or by
transplanting young trees. The cheaper plan is to leave
trees enough in the tracts cut over by the lumberman to
re-seed the land and so keep up the covering of forest.
But in treeless regions, as the prairies and the Great Plains,
it is often a matter of much importance to secure belts of
trees or considerable wooded areas (Sect. 423). This may
be done by planting the seeds of the desired species in the
places where the trees are to remain, or by setting out seed-
ling trees procured from nurseries. The latter plan is
much the more certain to insure success, as young trees
that have been once or twice transplanted have no long
roots and are not much checked in their growth by being
set out where they are finally to grow. Coniferous and
broad-leaved trees are freely planted on a large scale.
Among the most desirable species of the former are sev-
eral spruces, and the white pine, the Scotch pine, and the
Austrian pine. Broad-leaved trees which are consider-
ably planted, especially in the Central Plains region (e.g.,
Nebraska) are cottonwood, silver or white maple, green
ash, honey locust, hardy catalpa, black walnut, eucalyptus,
and red oak.
423. Influence of Forests on Climate and Water Supply.
— The effect which forests have on the temperature of the
air and on the amount of rainfall in their neighborhood
has not been fully determined. But it is well known that
woodlands and even narrow belts of timber are of great
service in winter by shutting off cold winds. For thus
acting as wind-breaks coniferous evergreen woods are of
course more effective than deciduous ones. Tree belts
have been largely planted in the more northerly prairie
states for the protection which they afford.t*
Plate XIV. Oak Saplings springing from a Stump.TIMBER; FORESTRY
353
Regulation of the water supply is, however, the most
important service which forests render, aside from their
value as sources of timber. It is a matter of common
observation that when a wooded region is stripped of its
trees, brooks and rivers are subject to violent floods in the
season of heaviest rain or at the melting of the snows,
while during the drier months springs fail and streams
run low, so that their beds may be only a series of pools.
These facts are due to the regulative effect of the forest
floor on the distribution of water which falls as rain or
snow. On bare ground, not even covered with grass, a
large portion of the rainfall is at once carried off to the
nearest streams. Even on grasslands the run-off is rapid,
as is shown by the quick rise of prairie rivers after a heavy
rain. But the leaf-covered forest floor, often carpeted
with moss, holds water like a sponge and continues to de-
liver it for many days after every heavy rain or period of
melting snow. This gradual delivery of water, part of it
draining off along the surface, part of it soaking into the
soil and then slowly finding its way underground into
springs and streams, makes tire watercourses of a heavily
forested region comparatively permanent and constant, de-
livering considerable water at all seasons of the year and
rarely overflowing their banks within a few hours after
rains. For this reason it is of the utmost importance that
wooded regions like the White Mountains, the Adiron-
dacks, the central and southern portions of the Appala-
chian system in which many streams have their sources,
should be protected by appropriate legislation as soon as
they are seriously threatened by the lumberman.APPENDIX I
[Additional illustrations, chiefly for use with the Flora
in determination of species.]
I. LEAF FORMS
a, linear; b, lanceolate; c, wedge-shaped; d, spatulate; e, ovate; /, obovate
g, kidney-shaped; h, orbicular; i, elliptical.
355350
ESSENTIALS OF BOTANY
Fig. 2. Tips of Leaves.
a, acuminate or taper-pointed; 6, acute; c, obtuse; cl, truncate; e, retuse;
/, emarginate or notched; g (end leaflet), obcordate; h, cuspidate, —
the point sharp and rigid; i, mucronate, — the point merely a pro-
longation of the midrib.
Fig. 3. A, Shapes of Bases of Leaves ; B, Peltate Leaf of Tropteolum.
1, hearLshaped; 2, arrow-shaped; 3, halberd-shaped.APPENDIX I
357
Fig. 4. I. A, Runcinate Leaf of Dandelion ; B, Lyrate Leaf.
II. Shapes of Margins of Leaves.
a (1), finely serrate; (2), coarsely serrate; (3), doubly serrate. 6(1), finely
dentate; (2), sinuate dentate; (3), doubly dentate, c, deeply sinuate.
d, wavy, e (1), creuate or scalloped; (2), doubly crenate.
II. FORMS OF FLOWER CLUSTERSESSENTIALS OF BOTANY
Fig. 6. I, Simple Umbel of Cherry ; II, Catkins of Willow.
A, staminate flowers; B, pistillate flowers.
A
Fig. 7. A, Spike of Plantain; B, Head of Fed Clover.APPENDIX I
359
Fig. 8. Head of Yarrow.
A, top view (magnified); B, lengthwise section (magnified), re, re-
ceptacle; i, involucre; r, ray-flowers; d, disk-flowers; c, corolla;
s, stigma; ch, chaff, or bracts of receptacle.360
ESSENTIALS OF BOTANY
Fig. 10. Diagrams of Inflorescence.
A, panicle; B, raceme; C, spike; B, head; umbel,
Fig. 11. Compound Cyme of Mouse-Ear Chickweed.
t, the terminal (oldest) flower.APPENDIX I
361
KINDS OF FLOWER CLUSTERS
A.	Indeterminate Inflorescence. — Order of blossoming from below
upward, or from without inward.
1.	Axillary flowers. Flowers growing in the axils of ordinary
leaves.
2.	Raceme. Flowers with flower-stalks called pedicels arranged
along the peduncle or stem in the axils of special (usually
pretty small) leaves called bracts.
3.	Corymb. Flowers arranged as in the raceme, but with the
lower pedicels so lengthened as to make the flower cluster
flat or nearly so (as in the hawthorn or the yarrow).
4.	Umbel. Flowers with pedicels of nearly equal length, all
appearing to spring from a common point, like the ribs of
an umbrella. An involucre of bracts usually surrrounds
the bases of the pedicels.
5.	Spike. Flowers as in the raceme, but sessile, that is without
pedicels.
6.	Head. Flowers as in the spike, but the cluster nearly
globular.
7.	Panicle. Flowers as in the raceme, but the cluster made
compound by the branching of the peduncle.
B.	Determinate Inflorescence. — Order of blossoming from within
outward.
1.	Flower terminal. One flower borne at the summit of the
stem.
2.	Cyme. Flowers much as in the umbel, but the innermost
blossoming first.APPENDIX II
LABORATORY DIRECTIONS
For much more detailed laboratory work than has been outlined in
the present book see Bergen and Davis’ Laboratory and Field Manual
of Botany (Ginn & Company). A series of type studies of spore-plants
and of representative species of seven families of seed-plants is there
given, and the subject of ecology is treated with some care. The
selection, preservation, and preparation of material for histological
work is carefully described. A glossary of botanical terms is given
in the Manual.
APPARATUS
The equipment of apparatus necessary for the laboratory and for
the individual student is discussed in the Manual. Some special
pieces of apparatus may, however, be mentioned in this place. For
experiments on the relation of temperature to the germination of
seeds, and for determining the highest temperatures which blue-green
algfe, bacteria, or other organisms can support, it is convenient to have
a small, warm chamber, or incubator (thermostat). Such a chamber
of 22 x 30 x 22 cm. inside dimensions may be had of Eirner & Amend,
205-211 Third Ave., New York, for $40, and larger ones at higher
prices if desired. For some purposes a differential thermostat, as
described by Professor IV. F. Ganong,1 is still better.
The apparatus to measure sap pressure (p. 47) may, as suggested
by Professor Ganong, advantageously be replaced by a pressure-gauge
consisting of a column of air contained in a perfectly cylindrical
glass tube, closed at the upper end. Before such a gauge is used
Boyle’s law for pressure and volume of gases should be explained to
the class and experimentally illustrated.
1 Laboratory Course in Plant Physiology, Henry Holt & Co., New York.
302APPENDIX II
363
Tools for the manufacture and repair of apparatus will be found
almost indispensable in the laboratory. Among the most useful are
round files for cork-boring and triangular ones for cutting glass, a
hammer, nails and brads, fine carpenter’s saw, hack-saw, pliers and
cutting pliers, chisels, brace with bits and twist drills, annealed brass
wire, small soldering copper with solder and zinc-chloride soldering
solution.
The Compound Microscope. — Compound microscopes and acces-
sories may be bought of most dealers in physical apparatus. Four
of the most important manufacturers are the Bausch & Eomb Optical
Co., Rochester, N.Y.; E. Leitz, 30 East Eighteenth St., New York
City ; the Spencer Lens Co., Buffalo, N.Y.; and C. Zeiss, represented
by the Bausch & Lornb Co. All send catalogues on application, and
all furnish instruments suitable for high-school laboratories at prices
ranging from $'20 to $35. The microscopes of German manufacture
(of Leitz and Zeiss) are imported duty free for schools.
A very brief account of the construction and use of the compound
microscope is given in the Manual, pp. 10-14. More details can be
found in Winslow’s Elements of Applied Microscopy, John lYiley &
Sons, N.Y., or in any of the standard treatises, such as Gage’s, or
Carpenter and Dallinger’s.
School microscopes are very commonly provided with a 2-inch
and a 1-inch eyepiece and a |-inch and J-inch objective. In this
case either eyepiece when used with the lower objective will give
a low power. The 2-inch eyepiece with the -J-inch objective will give
a medium power, and the 1-inch eyepiece with the £-inch objective
w7ill give a moderately high power.
It will be found desirable to equip many if not all of the stands
also with a 2-inch objective, as this gives a far better general view
of such objects as sections of roots or stems of seed plants, green
algae, small liverworts, fern prothallia, and so on than can be ob-
tained with a hand lens. If possible, the laboratory should have at
least one stage micrometer, several eyepiece micrometers, and a cam-
era lucida. The micrometers should be kept in frequent use to give
the students accurate ideas of the dimensions of objects studied,
and the camera lucida should be used as a check on the accuracy of
drawings made from the microscope without it.364
ESSENTIALS OF BOTANY
BIBLIOGRAPHY
In this place only a few suggestions will be given to supplement
the bibliography of the Manual. The books which are there double-
starred are among the most important for reference. Some, how-
ever, like Pfeffer’s Physiology of Plants, are very expensive, and such
briefer works as Peirce’s Text-Book of Plant Physiology (Henry Llolt &
Co., New York), or Green’s Introduction to Vegetable Physiology (P.
Blakiston’s Sons & Co., Philadelphia), may be bought as an alter-
native. It is often found difficult to identify even the genera of algee
and fungi which are encountered in collecting. For fresh-water
algfe and some aquatic fungi no book is more useful than Whipple’s
Microscopy of Drinking Water (John Wiley & Sons, New York).
Many fungi can be identified by means of Massee’s Text-Book of
Fungi (The Macmillan Company, New York).
SPECIAL TOPICS FOR STUDY
Economic Botany.-—Few subjects will be found to interest most
classes more than some of the topics of economic botany. These
can often be assigned for optional work, for which credit may be
given. The topics to be suggested would vary much, according to the
environment of the school. In agricultural districts reports on local
conditions as regards use of improved seed for farm and garden
crops, on trials of new economic plants, on tree-planting and the
management of wood lots, would all prove valuable subjects for
discussion. City high-school classes can find fewer opportunities
for reports and investigations, but some practicable topics are the
comparative value of various species of shade trees and the insect
enemies of each species, the sources of the winter flower-supply and
modes of forcing flowers, the examination of the gross and histological
characteristics of woods and the classification of these by families
and according to their structural likenesses, the study of commer-
cial fibers, the histological examination of vegetable foods (such as
starches) and of powdered drugs. Many interesting and valuable
studies of the relation of microscopic organisms to fermentation and
decay may be made with simple apparatus, as described in Conn’s
Bacteria, Yeasts, and Molds in the Home (Ginn & Company).APPENDIX II
365
Ecology. — It will not usually be found worth while to undertake
ecological studies unless considerable field work (or at any rate, out-
of-door work) can be done. It is almost useless to discuss adapta-
tions to environment unless the environment itself is as much under
observation as are the plants that live in it. A good deal of ecology
can be interwoven during trips undertaken mainly for the purpose of
getting acquainted with the local flora and collecting for the school
museum and laboratory. The first requisite for teaching the rudi-
ments of ecological botany is to impress upon the student the reality
and severity of the struggle for existence among plants, since compe-
tition must exist in order to make adaptation necessary. Any such
studies as are suggested in Sects. 154-156 of the Manual may be
undertaken for this purpose. Even boxes of seedlings grown in a
Wardian case or on a sunny laboratory window sill will help to show
the effects of competition.
Many ecological topics, such as field studies of parasitism, of insect
pollination, of ecological classes, or of plant formations may profitably
be assigned as voluntary work to single students or small groups
observing together.
INTERPRETING RESULTS OF LABORATORY WORK
Most of the results of physiological experiments can be judged by
reference to the statements of Pfeifer, Detmer, and other authorities,
and morphological and histological work may be reviewed by com-
parison with the statements and the figures found in such general
treatises as the Strasburger text-book, in the Strasburger-Hillhouse
Practical Botany, and in special works. But the teacher will find it
indispensable to keep for reference a full illustrated set of notes of
the year’s work, and to add to this year by year as additional types
are studied or new results are obtained in any of the experiments
performed as demonstrations or by the class.■INDEX
Starred page numbers indicate where cuts occur. App. refers to the Appendix.
Absorption of carbon dioxide, 136-
140.
Absorption, selective, 44.
Acacia, leaf of, *110.
Accessory buds, 88, *89, *90.
Accessory fruits, *189, 190.
Acuminate, App. I, *356.
Acute, App. I, *356.
Adaptations to conditions of exist-
ence, 204, 205.
Adherent, 155, *156.
Adventitious buds, 95.
Adventitious roots, 30, *31.
Aerial roots, 30, *31.
Agaricus. See Psalliota.
Age of trees, 64, 55.
Aggregate fruits, *189.
Ailanthus twig, *88.
Air chamber, *128, *129.
Air, relation to germination, 8-10.
Akene, *185, 186.
Albuminous substances, 19.
Algae, 215-238*.
Algal fungi, 239, 246-249*.
Alternate, *52.
Alternate leaves, *106. *
Alternation of generations, 270,
271, *285, 286.
Anatomy of plants. Seeunderi?oof,
Stem, Leaf, Flower, Fruit, Struc-
ture of.
367
Angiosperms, 153, 154.
Animal food, need of, 122.
Animals, defenses against, 123-
126*.
Annual growth, indefinite, 54.
Annual ring, *73.
Annuals, 54.
Anther, *153.
Anther, modes of opening, *162.
Antheridia, 224, *226, *229, 232-
236*.
Antipodal cells, *166.
Ants plant seeds, *199.
Apetalous, *149.
Apple, *322.
Apple leaf, stipules of, *100, 101.
Aquatic roots, 31, 32.
Arch of hypocotyl, 22, *23, 24.
Archegonia, *226, *229, 232-236*.
Aristolochia’stem, bundle of, *69.
Aristolochia stem, cross-section of,
*68, 70.
Arrangement of leaves, 105-110*.
Arrow-shaped, App., *356.
Ascus, 252, *253.
Asexual generation, *281, *292.
Asparagus, 61, *62.
Aspergillus, *251.
Aspidium, *281.
Asplenium, type study, 282-285*.
Assimilation, 140.868
ESSENTIALS OF BOTANY
Australian blackberry, leaf of, *116.
Axillary bud, 88, 89, *90.
Axillary flowers, App. I, *357.
Bacilli, *242.
Bacteria, 240-244*.
Bacteria, type study, 240, 241.
Banana, 328.
Barbed hairs, 124, *120.
Barberry, spiny leaves of, *123,
124.
Bark, 67-73*, 76, 77.
Basidia, 261, *262.
Basidia fungi, 255-262*.
Bast, *68, *09, *70, *72.
Bast-bundle, *68, *69.
Bean-pod, study of, 183.
Bean seed, *6.
Bees, 169-173*, *176.
Beet leaf, *128.
Beggar’s-ticks, *197.
Bell-shaped, *152.
Berry, 181, 188, 329.
Berry, study of, 181.
Biennial, 38, 39, 54.
Bilateral symmetry, *150.
Birch, branching of, *53.
Bird-pollinated flowers, 174.
Birds plant seeds, 198.
Black mold, type study, 240-
249*.
Blackberry hybrids, 320.
Bladder-wrack, 2.30-233*.
Blue-green algte, 216-218*.
Box-elder, buds of, *89.
Box-elder, radial and cross-sections
of stem of, *70.
Bract, App. I, *357.
Branches formed from adventitious
buds, 95.
Branching, alternate, *52.
Branching and leaf-arrangement,
51, *52.
Branching, opposite, *52.
Brazil nut, food stored in, 20.
Breathing-pore, *129.
Brown algse, 230-234*.
Bryophytes, 265-279*.
Buckeye, bud of, *87.
Bud, horse-chestnut, 80, 87.
Bud-scales, 86, *87, 88, *92.
Buds, 86-96*.
Buds, adventitious, 95.
Buds, dormant, 95.
Buds, naked, *S8.
Buds, position of, 88, *89, *90, *97.
Buds, structure of, 86, *87, *92.
Bulb, 59, *60, *61.
Bulb, hyacinth, *60.
Bulb, onion, 59, *61.
Burs, 195, *196, *197.
Buttercup, leaf of, *100.
Buttercup, study of flower of, 146,
147.
Butternut, buds of, 89, *90.
Cabbage, a bud, 89.
Cabinet woods, 346.
Cacao tree, *327.
Cactus, 61, *117.
Cactus flower, transitions in, *159,
160.
Caladium, 59.
Calyx, *148.
Cambium, 68-73*.
Cambium-layer, 71, *72, *73.
Canua, parallel veining in, *101.
Capsule, 187, *194.
Carbon dioxide, absorption of, 136,
137.INDEX
369
Carbon dioxide, disposition of, 137,
138.
Carnivorous plants, *118, *119,
*120, *121, 122.
Carpel, 153, *185, *180.
Carrot, root, *307.
Castor-oil plant, early history of
stem of, *71.
Catkin, App. I, *358.
Celandine, leaf of, *99.
Cell, 16, 17, 43-45*.
Cell-contents, *17, *43.
Cell-division, *218, *222, *245.
Cell-multiplication in Spirogyra,
*222.
Cell-sap, *43, *46.
Cell-wall, 17, 44, *218, *222.
Cellulose, 44.
Central cylinder, *36, *37.
Central pjacenta, *155.
Chemical changes in leaves before
falling, 141.
Cherry twig, *92.
Chestnut fruit, *186.
Chlorophyll, *129, 130, 138-140.
Clioripetalous, 151.
Chorisepalous, 151.
Cilium, *226, *232, *242.
Citrous fruit hybrids, *320, 321.
Cladophora, 212, 213.
Cladophyll, 62, *63.
Class, 209.
Classification, 207-210.
Cleistogamous flowers, 179, *180.
Clerodendron, *175.
Climbing plants, *56, *57.
Clover leaf, *109.
Club-mosses, 291, *292.
Cluster-cup, *256.
Cocoanut, *326.
Coffee, 326, *328.
Coleochsete, *300.
Colors of flowers, 171, 172.
Compass-plant, nearly vertical
leaves of, 110, *111.
Composite head, App. 1, *359.
Compound cyme, App. I, *360.
Compound leaves, *103, 104.
Compound pistil, 154, *155.
Compound umbel, App. I, *359.
Conceptacles, 231-233*.
Concord grape, 309.
Coniferous woods, 343, 344.
Conjugating algte, 219-223*.
Conjugation, 221-223*, *248.
Connective, *153.
Contractility, 45.
Cork, *70, *73, 76, 84.
Corn breeding, 313, 314.
Corn, cross-section of stem of,
*65.
Corn, germination of, 6, 7.
Corn, grain of, 13, *14.
Corn, root-tip, section of, *36.
Corn-stem, structure of, *65.
Corolla, *148.
Corymb, App. I, 361.
Cotton, 341.
Cotyledon, *5, *6.
Cotyledon, disposition made of,
24.
Cotyledons, thickened, use of,
24.
Crenate, App. I, *357.
Cross-pollination, 168.
Crow-berry, rolled-up leaf of, *117.
Cryptogams. See Spore-plants.
Cuspidate, App. I, *356.
Cutting leaves, *120.
Cyme, App. I, 361.370
ESSENTIALS OF BOTANY
Dahlia, thickened roots of, 33, *34.
Daily movements of leaves, 108,
*109, *110.
Dandelion, *55.
Datura, stigma of, *164.
Deciduous, 141.
Defenses against animals, 122-126*.
Definite annual growth, 54.
Dehiscent fruits, 185, *186, *187,
*194.
Deliquescent trunk, 53.
Dentate, App. I, *357.
Descent of water, *70, 80, 81.
Desmids, *219.
Destruction of plants, 203.
Determinate inflorescence, App. I,
361.
Deutzia leaves, *108, *109.
Diadelphous, 153, *155.
Diagrams, floral, *156, *157.
Diatoms, *219, 235-237.
Dichogamy, *175, 176.
Dicotyledonous plants, 28, 211.
Dicotyledonous stem, annual, gross
structure of, 67, *68.
Dicotyledonous stem, cross-section
of, *68, *70, *72, *73.
Dicotyledonous stem, minute struc-
ture of, *69.
Dicotyledonous stem, rise of water
in, 78-80, *81.
Dimorphous flowers, *178.
Dioecious, *149.
Discharge of pollen, *162.
Diseases, varieties resistant to, 322,
323.
Dispersal of seeds, 191-199*.
Distinct, 151.
Distribution of material in mono-
cotyledonous stems, 66, 07.
Division of labor, 304-308.
Dock fruit, study of, 183, 184.
Dodder, 32, *33.
Dormant buds, 95.
Double flowers, 160.
Drosera, *119, *120, *121.
Drought, endurance of, 115.
Drought-plants, 114.
Dry fruits, 187.
Duct, *69, *70, 78.
Dyes, 339.
Earliest plants, 255, 256.
Ecology, 2, 105-125*, 108-180*,
191-199*.
Egg, osmosis in, 45, *46.
Egg-cell, 165, *166.
Elaters, 288, 201.
Elliptical, App. I, *355.
Elm bud, *92.
Elm fruit, *187.
Elm leaf, 97, 98.
Elm twig, *92.
Emarginate, App. I, *356.
Embryo, 5, 14.
Embryo sac, *166.
Endosperm, *13, 14, *17.
Energy7, source of, in plants, 140,
141.
Epidermis of root, *36, *37.
Epidermis, uses of, 131, 132.
Epigynous, *156.
Epipetalous, 155, *156.
Equisetum, type study, 287-290*.
Essential organs, *148.
Euphorbia splendens, *125.
Evergreen, 141.
Evolutionary history of plants, 295-
305*.
Excretion, 44.1XDEX
371
Excretion of water, 134, 135.
Excurrent trunk, 52.
Existence, struggle for, 200-200.
Exogenous, 71.
Explosive fruits, 191, 192.
Fall of horse-chestnut leaf, *102,
104.
Fall of the leaf, 141, 142.
Family, 208.
Family, subdivisions of, 209.
Fascicled roots, *34.
Fermentation, 245, 246.
Fern-plants, 280-294*.
Ferns, 280-287*.
Fertilization, 165-167*.
Fertilizers, vegetable, 337-339.
Fibers, 340, 341.
Fibrous roots, *34.
Fibro-vascular bundles, *65.
Filament, *153.
Fittest, survival of, 205, 206.
Fleshy fruits, 187.
Fleshy fruits, uses of, 197, 198.
Fleshy roots, 37-39.
Floating seeds, 195.
Floral diagrams, *156, *157.
Floral envelopes, *148.
Floral organs, movements of, 175—
177*.
Flower, nature of, *159, *160.
Flower, organs of, *148, 149.
Flower, plan of, 148-157*.
Flower-buds, position of, *90, *91.
Flowerlessplants. See Spore-plants.
Flowers, bird-pollinated, 174.
Flowers, colors of, 171, 172.
Flowers, ecology of, 168-180*.
Flowers, odors of, 170, 171.
Flytrap, Venus, *121, 122.
Follicle, *186.
Food in embryo, 12.
Food, storage of, in root, 37, 38.
Food, storage of, in stem, 82-85.
Food, storage outside of embryo, 12.
Foods for animals, 336, 337.
Foods, human, 324-335.
Forestry, 348-353.
Forests, influence on climate and
water supply, 352, 353.
Formative tissue, *71.
Fossil plants, 236, 237, 293, 294,
298.
Four-o’clock seed, 13.
Foxglove, pinnate leaf of, *98.
Free, 155, *156.
Free central placentation, *155.
Frond, *281.
Fruit, 181-199*.
Fruit, definition of, 185.
Fruits, study of, 181-184.
Fruits, uses of, 191-199*.
Fucus, type study, 230-233*.
Fuel, 348.
Funaria, *276.
Fungi, 239-264*.
Fusarium, 323.
Gamete, *221, 225, 228, 229, *232,
*248, *268, *269, *276, *285.
Gametophyte, 271, 275, 277, *283,
286', 291, 293.
Gamopetalous, *152.
Gamosepalous, *152.
Generations, alternation of, 270.
Generative cell, in pollen tube, *165.
Genus, 207, 208.
Germination, 4-11*.
Germination, chemical changes dur-
ing, 9, 10.	*372
ESSENTIALS OF BOTANY
Germination, conditions of, 7-9.
Gill fungi, 259-262*.
Gills, *260, *261.
Gipsy moth, 350, 351.
Gourd-fruit, 188.
Grafting, *75.
Grain, 186, 324, 325.
Grape hybrids, 319.
Grape sugar, 85.
Grapes, 330.
Gray, Asa, 55.
Green algae, 225-230*.
Green layer of bark, 69.
Growing point, 6, *36.
Growth, secondary, 71,*72,*73, 74.
Guard-cells, *128, *129, 132.
Gymnosperms, 153, 211.
Hairs, 132.
Hairs, stinging, 124, 125, *126.
Halberd-shaped, App. 1, *356.
Halophytes, 114, 118.
Hard bast, *68, *69, *70, *73.
Hard woods, 344-348*.
Haustoria, 32, *33.
Hay, 336.
Head, App. I, *358.
Heart-shaped, App. I, *356.
Heartwood, 74, 77.
Ileliotropism, 111, 112.
Herbs, 54.
Hesperidium, 181, 182, *188.
Heterospory, 293.
Hilum, *5.
Honey-bee, leg of, *170.
Hop, twining of, *57.
Horse-chestnut bud, study of, 86,
87.
Horse-chestnut twig, 49, 50.
Horsetails, 287-291*.
Host, 32, *33.
Hot springs, plants in, 204.
Hyacinth, bulb of, *60.
Hybrid, 316.
Hybridization, 316.
Hybridizing, 316-323.
Hydrangea, transpiration in, *133,
134.
Hydrogen, 138.
Hydrophytes, 114, *115.
Hymenium, *261, *262.
Hyphte, *247, *249, *251, *255.
Hypocotyl, *5, *23, *71.
Ilypocotyl, cross-section of, *71.
Hypogynous, 155, *156.
Imperfect flowers, *149.
Indefinite annual growth, 54.
Indehiscent fruits, 185, *186.
Indeterminate inflorescence, App.
I, 361.
Indian corn, germination of, 6, 7.
Indian corn, hybridizing, 317.
Indian corn, kernel of, *14.
Indian corn, root-tip, *36.
Indian corn, structure of stem, *65,
66.
Indian pipe, 139.
Indusium, *281.
Inflorescence, App. I, 358^361*.
Inflorescence, diagrams of, App. I,
*360.
Insect pollination, 169-180*.
Insect pollination, study of, 180.
Insect visits, *172, *173.
Insect-traps, leaves as, 119-122*.
Insectivorous plants, 119-122*.
Insects, pollen-carrying apparatus
of, 169, *170.
Insects, sense of smell of, 170, 171.IMIEX
373
Insects, vision of, 171.
Insertion of floral organs, *150.
Internode, 26, 65.
Involucre, App. I, *350.
Ipomcea Jalapa, 38.
Ipomcea, rate of increase of, 201,202.
Irritability in plants, nature and
occurrence of, 45.
Ivy, aerial roots of, 30, *31.
Keel, *150.
Kidney-shaped, App. I, *355.
Labiate, *152.
Lanceolate, App. I, *355.
Lateral buds, 59, *88, *89.
Leaf, 97-142*.
Leaf, accumulation of mineral
matter in, 135.
Leaf, fall of, 141, 142.
Leaf-arrangement, 105-108*.
Leaf-bases, App. I, *356.
Leaf-buds, *89, *90.
Leaf-like stems, 61, *02, 63.
Leaf-margins, App. I, *357.
Leaf-mosaic, 106, *107.
Leaf-outlines, App. I, *355.
Leaf-sections, 127, *128.
Leaf-spine, *123, 124.
Leaf-stalk, *98.
Leaf-tendril, *103.
Leaf-tips, App. I, *356.
Leaf-traces, 79, 130.
Leaves as insect-traps, 119-122*.
Leaves, compound, *102, *103, 104.
Leaves, cutting, 125, *126.
Leaves, divided, *99, *100, 107,
108, *110.
Leaves, functions of, 130-142*.
Leaves, movements of, 108-112*.
Leaves, simple, 97-103*.
Leaves, structure of, 127-130*.
Legume, 183, 187, *194.
Lemon, study of, 181, 182.
Lenticels, 76.
Lianas, 56.
Lichens, 253-255*.
Life histories, *277, *285.
Light, exposure to, 105-112*.
Light, movements towards, *111,
112.
Lily leaf, 127.
Lily, pollen grains producing tubes
on stigma, *165.
Limb of calyx or corolla, 152.
Lime, 135.
Linden, fruit cluster of, *192.
Linden fruit, *192.
Linden wood, structure of, *73.
Linear, App. I, *355.
Liverworts, 205-272*.
Living parts of the stem, 70-78.
Locules, *155.
Locust, pinnately compound leaf
of, *103.
Locust, thorn-stipules of, 124, *125.
Lufia, 68.
Lunularia, 206.
Lycopodium, *292, 293.
Maidive nut, 195.
Malt, 11.
Maltose, 85.
Mangrove, 204.
Maple fruit, *187.
Maple leaf, 99, 100.
Marchantia, type study, 266-270*.
Marsilia, *287.
Mechanics of monocotyledonous
stems, 66, 67.374
ESSENTIALS OF BOTANY
Medicinal plants, 335, 336.
Medullary ray, *68, *70, *71, *72,
*73, 74.
Megaspore, *301.
Megasporophyll, 302.
Melon, palmately netted-veined leaf
of, *99.
Melon-cactus, 61, *117.
Mesophytes, 114, 118.
Micropyle, 5.
Microsplisera, type study, 250-252*.
Microspores, *301.
Microsporophyll, 302.
Midrib, 98.
Mineral matter accumulated in the
leaf, 135.
Mnium, type study, 272-277*.
Mold, black, type study, 246-249*.
Monadelphous, *154.
Monocotyledonous plants, 28, 211.
Monocotyledonous stems, *65, 60,
67.
Monocotyledonous stems, growth
of, in thickness, 67.
Monocotyledons, 211.
Moncecious, 149.
Monotropa, 139.
Morchella, *252, *253.
Morel, *252, *253.
Morning-glory, rate of increase of,
201, 202.
Morphology, 1, 27.
Mosaic, leaf, 106, *107.
Mosses, 272-279*.
Moths, *174.
Movement of water in plants, 39,
40, 46-48*, 78-81, *81.
Movements of floral organs, *170,
*177.
Movements of leaves, 108-112*.
Movements toward light, 111, 112.
Mucronate, App. I, *356.
Mulberry, *189.
Multiple fruits, *189, 190.
Mushroom, type study, *260, *261.
Mutilated seedlings, growth of, 12,
*13.
Mycelium, *247, *251.
Myrsiphyllum, *62.
Naked buds, *88.
Nasturtium leaves, starch in, 139,
*140.
Nasturtium, study of, 1-3.
Natural selection, 206.
Nectar, 170.
Nectar-glands, 170, *171.
Nectar-guides, 172.
Nectaries, 170.
Negundo, radial and cross-sections
of stem of, *70.
Netted-veined, *98, *99.
Nettle, stinging hair of, *126.
Nightshade, leaf of, *124.
Nitrogen, 140.
Nocturnal position, *109, *110.
Node, 26, 65.
Nucleus, *43, *222.
Nucleus of root-hair, *46.
Nut, *186.
Nutrient substances, 137-140.
Oak leaves, arrangement of, 105,
*106.
Oat, root-system of, 39.
Obcordate, App. I, *356.
Obovate, App. I, *355.
Obtuse, App. I, *356.
Odors of flowers, 170, 171.
Offensive-smelling plants, 125.INDEX
375
Oil, 18, 19.
Oil, essential, 21.
Oil, extraction, 18, 19.
Oil, testing seeds for, 19, 20.
Onion, bulb of, 59.
Onion leaf, section of, *61.
Onion, structure of, 84, 85.
Onion, tests for food-materials in,
85.
Onoclea, *280.
Oogonia, *226, *229, *232.
Oosphere, *232.
Opposite, 51, *52, 106, *107, *108,
*109.
Oranges, 329. 330.
Orbicular, App. I, *355.
Orchid, aerial roots of an, 30.
Organs, essential, *148.
Organs, vegetative, 24, 25.
Ornamental plants, 342.
Oscillatoria, type study, 216-218*.
Osmosis, 45^17*.
Osmosis in an egg, 45, *46.
Osmosis in root-hairs, *46, 47.
Ovary, *154-156.
Ovate, App. I, *355.
Ovoid, egg-shaped, like the spores
in Fig. 182.
Ovule, 153, *154.
Ovule, spruce, fertilized, *302.
Ovule, structure of, *166.
Oxalis leaf, development of, *94.
Oxidation, 10.
Oxygen, 10, 136.
Oxygen making, 137.
Palisade-cells, *128.
Palmate, 100, *102, 103.
Pampas region, 204.
Panicle, *193, App. I, *359.
Pansy, leaf-like stipules of, *101.
Papilionaceous corolla, *150.
Papillae on stigma of a lily, *165.
Parasites, 32, *33.
Parasitic roots, 32, *33.
Parietal placenta, *155.
Parsnip root, study of, 37, 38.
Pea seed, *8, 12, *13.
Pea seedling, mutilated, 12, *13.
Pear buds, *91.
Pear fruit spurs, *91.
Pedicel, App. I, *357.
Peduncle, App. I, 357.
Peg of squash seedling, 23, 24.
Peltate, App. I, *356.
Pepo, 188.
Perennial, 39, 54.
Perianth, *148.
Pericarp, 187.
Perigynous, *156.
Perisperm, 13.
Petal, 143, 146, 148.
Petiole, 98.
Phanerogams, 209, 211.
Phanerogams, classes of, 211.
Phosphorus, 135.
Phytopthora, *249.
Pine, seedling, *28.
Pinnae, leaflets of a pinnately com-
pound leaf, *103.
Pinnate, *98, *99, *103.
Pinnules, *244, 245.
Pistil, 143-145, 147, *148, *151,
*153, 154.
Pistil, parts of, *153.
Pitcher-plant, *118. 120.
Pith, *65, 66, 67, *68, *70, *71, *72.
Placenta, 154, *155.
Plant breeding, 309-323.
Plant societies, 113, 114.376
ESSENTIALS OF BOTANY
Plant society, 113.
Plants, classes of, in relation to
economy of water, 115-118*.
Plants, destruction of, by animals,
122.
Plants of uneatable texture, 123.
Pleodorina, *298.
Pleurococcus, 212.
Plum hybrids, *319.
Plumule, *5, *14.
Pod, 183, 187, *194.
Poisonous plants, 125, 126.
Poisonous seeds, 21.
Poisons, plants containing, 125,126.
Pollarded trees, 95.
Pollen, 162-169*.
Pollen, discharge of, *162.
Pollen grain, germination of, *165.
Pollen grains, *163.
Pollen grains, number of, per ovule,
167.
Pollen, protection of, from visitors,
173.
Pollen tubes, 103, 164, *165.
Pollen-carrying apparatus, 169,
*170.
Pollination, 168-180*.
Polypetalous, 153.
Polysepalous, 153.
Pome, 188.
Poplar, leafy twig of, *97.
Poplar twig, 51.
Potato tuber, 59, *60, 83, 84, 332,
333.
Prickle, *123, *124.
Prickly leaves, *124.
Primary root, *14, 30.
Primrose, pollination in flowers of,
*178.
Procambiuin, *71.
Propagation, by root, 42.
Protection of plants from animals,
122-126*.
Proteids, 19, 20.
Proteids, tests for, 20.
Prothallium, *283, *284, *290.
Protonema, *274.
Protoplasm, *43, 44, 45.
Protoplasm, characteristics of, 44,
45.
Psalliota, type study, 259-261*.
Pteridophytes, 280-294*.
Pteridophytes, remarks on, 293,294.
Puccinia, type study, 255-258*.
Raceme, App. I, *357.
Raspberry, *189.
Ray, medullary, *70, *71, *72, *73,
74.
Ray-flowers, App. I, *359.
Receptacle, 150, *156.
Red algae, 234-237*.
Red clover, leaf of, *109.
Regular flowers, 149.
Reproduction in seed plants, 165-
167*.
Respiration, 136, 140, 141.
Retuse, App. I, *356.
Rhachis, 282.
Rhizoids, hairs serving as roots
in ferns, mosses, and liverworts,
*265, *273.
Rhizopus, type study, £46-248.
Ring, annual, *73.
Ringent, *152.
Rise of water in stems, 78-80.
Rockweed, type study, 230-233*.
Root, 30-42*.
Root, adaptation to work, 41, 42.
Root, dicotyledonous, section, *37.INDEX
877
Root, elongation of, 25.
Root, fleshy, 37, 38.
Root-eap, 35, *36.
Root-climbers, 56.
Root-liair, *27, *37, *40, *47.
Root-pressure, *47, 48.
Root-section, *36, *37.
Root-system, 30.
Roots, absorbing surface of, 39-41.
Roots, adventitious, 30, *31.
Roots, aerial, 30, *31.
Roots, fascicled, *34.
Roots, fibrous, *34.
Roots, growth of, 25.
Roots, movements of young, 40, 41.
Roots, parasitic, 32, *33.
Roots, primary, *14, 30.
Roots, propagation by, 42.
Roots, selective action of, 40, 47.
Roots, storage of food in, 37-39.
Roots, structure of, 34-38*.
Roots, water, 31, 32.
Rootstock, *58, *59.
Russian thistle, *193, 205.
Russian thistle, spread of, 205.
Rust, 224-228*.
Rust, wheat, study of, 226-228*.
Sac fungi, 250-255*.
Sago-palm, 82.
Salver-shaped, *152.
Salvinia, *301.
Sap, descent of, 78, 80, *81.
Sap, rise of, 78-80.
Saprophytes, 139, 233.
Sapwood, 74, 78.
Scalloped, App. I, *357.
Scion, *75.
Sclerenchyma, 66.
Seasonal plants, 114.
Secondary growth, 71-74*.
Secondary root, 30.
Sections, leaf, 127, *128.
Sections, root, *36, *37.
Sections, wood, *70, *73.
Seed, 4-21*.
Seed-leaf, *5, 6, 24.
Seed-plants, 209, 211.
Seed-plants, classes of, 211.
Seedlings, 22-29*.
Seedlings, mutilated growth of, 12,
*13.
Seeds, containing poisons, 21.
Seeds, dispersal of, 191-199*.
Selaginella, 291, 292.
Selection, artificial, 310-315.
Selection, natural, 206.
Selective absorption, 44.
Self-pollination, 168.
Sepal, 143, 146, 148.
Separated flowers, 150, *157.
Serrate, App. I, *357.
Sexual generation, 237.
Shoot, 25.
Shrubs, 54.
Sieve-cells, *69, *70, *72, 78.
Silica, 135, 250.
Simple leaves, 103.
Simple pistil, 154.
Simple umbel of cherry, App. I,
*358.
Sinuate, App. I, *357.
Sleep of leaves, *109, *110.
Slime-molds, *297.
“ Smilax,” *62.
Solomon’s seal, parallel-veined leaf
of, *101.
Sori, *281.
Spatulate, App. I, *355.
Species, 207, 208.378
ESSENTIALS OF BOTANY
Sperm cells, *165, 224-285*.
Sperm nucleus, 166.
Spike, App. I, *358.
Spine, 123-125*.
Spirogyra, type study, 219-223*.
Sporangium, *281.
Spore, 211, *221, *226, *236, *237,
*248, *249, *251, *253, *256, *257,
*262, *281, *297, *301.
Spore-capsules, *271, *273.
Spore-cases, *281, *301.
Spore-plants, 210-294*.
Spore-plants, classes of, 210.
Sporophyll, 286, 302, 507.
Sporophyte, *273, *275, *281, *284,
*286, *289.
Spruce, fertilized ovule of, *302.
Squash seed, 4-5*.
Squash seed, section, *5.
Squash seedling, 23, 24.
Stamen, *148, *153.
Stamen, parts of, *153.
Standard, *150.
Starch, 15-18*, 82, 138-140.
Starch disappears during germina-
tion, 18.
Starch food for man, 333, 334.
Starch in leaves, 138, 139.
Starch, testing seed for, 15, 16.
Stem, 49-85*.
Stem, definition of, 49.
Stem, dicotyledonous, annual, gross
structure of, 67-69*.
Stem, dicotyledonous, minute struc-
ture of, 69, 70.
Stem, early history of, *71.
Stem, functions of cells of, 77, 78.
Stem, monocotyledonous, *66, 66,
67.
Stem, structure of, 65-74*.
Stem-structure, early history of, Il-
ls*.
Stemless plants, *55, 56.
Stems, 49-85*.
Stems, climbing, *56, *57, 58.
Stems, storage of food in, 82-85.
Stems, twining, *57, 58.
Sterigmata, *262.
Sterilization, 241-243.
Stigma, *154.
Stigma, structure of, *164, *165.
Stinging hair, *126.
Stipe, *228, 229.
Stipules, *100, *101.
Stomata, *128, *129, 130, 132, 133.
Stomata, operation of, 132, 133.
Stone-fruit, *187.
Storage of food in the root, 37-39.
Storage of food in the stem, 82, 83.
Strawberry, *189.
Struggle for existence, 200-206.
Style, *153, *166.
Sugar, 11.
Sugar beet, breeding, 311-313.
Sugar, food for man, 334, 335.
Sugar, formed during germination,
11.
Sundew, 119-121*.
Superior, 155, *156.
Supernumerary buds, 89.
Survival of the fittest, 205, 206.
Sweet pea, flowers, *160.
Symmetry of flowers, 160.
Sympetalous, 151.
Synsepalous, 151.
Tangelo, *320.
Tanning materials, 340.
Taper-pointed, App. I, *356.
Taproot, *34.INDEX
379
Tea, 333.
Teleutospores, *257, *258.
Temperature and root-absorption,
40.
Temperature, relation to germina-
tion, 7, 8.
Tendril, *103.
Tendril climbers, *56, 57.
Terminal bud, 50. 88, *90.
Terminal flowers, App. I, *300.
Tertiary root, 30.
Testa, *5.
Thallophytes, 214-204*.
Thallus, 212.
Thermostat, 8.
Thistle, Russian, *193, 205.
Thorns as branches, 124.
Thyme, stoma of, *129.
Tickle-grass, *193.
Timber, 343-348.
Timothy, variations in, 310.
Tomato, study of, 181.
Trametes, *259.
Transition from stamens to peta^,
*160.
Transpiration, 131-135.
Transpiration, amount of, 134, 135.
Transpiration, measurement of,
*133, 134.
Transportation by water, 195.
Tree planting, 351, 352.
Trees, 54.
Trees, age of, 54, 55.
Trillium, study of flower of, 143,
144.
Tropteolum leaf, App. I, *356.
Tropseolum leaves, starch in, 139,
*140.
Tropseolum, petiole, coiling of, *57.
Tropaeolum, study of, 1-3.
Tropophytes, 114.
Truncate, App. I, *356.
Trunk, 52.
Tuber, 59, *60.
Tubular corolla, *152.
Tulip, study of flower of, 144-
146.
Tumble-weeds, *193, 194.
Turnip, seedling, *27.
Twayblade, beetle on flower of,
*172.
Twigs, study of, 49-51.
Twiners, *57.
TJlothrix, *305.
Umbel, App. I, *359.
Umbellet, App. I, *359.
Underground stems, 58-61*.
Uneatable plants, 123.
Union of pistils, 154.
Union of stamens, 153.
Unisexual flowers, *149.
Uredospores, *257.
Variety, 208.
Varnishes, 339.
Vaucheria, type study, 225-229*.
Vegetation, aquatic, 115.
Vegetative organs, 24, 25.
Vein, *98, *99, *101.
Veining, *98, *99, *101.
Venation, *98, *99, 100, *101, 102.
Venus’ flytrap, *121.
Vernation, 92, *93, *94.
Vertically placed leaves, 110, *111.
Vessel, 74, 78.
Water, absorption by roots, 39, 40.
Water, amount transpired, 134,135.
Water, course through leaf, 134.380
ESSENTIALS OF BOTANY
Water, excretion of, 133-135.
Water, movement of, 78-81.
Water, relation to germination, 8.
Water roots, 31, 32.
Water-lily, white, insertion of floral
organs, *156.
Water-lily, white, transitions from
petals to stamens in, *160.
Weapons of plants, 123-125*.
Wedge-shaped, App. I, *355.
Weeds, 200, 201.
Wheat-breeding, 314-316.
Wheat-grain, section of, *17.
Wheat-rust, type study, 255-259*.
Wheel-shaped, *152.
Willow, adventitious buds of, 95.
Willow, flowers of, 150, *151.
Wind-pollination, 168, 169.
Windsor bean seedling, *6.
Winged fruits, *187.
Wings, *150.
Wood of linden, *73.
Wood sections, *70, *73.
Wood, structure of, *73, 74.
Wood, varieties of. See Timber.
Wood-cell, *69, *70.
Work of leaf, 136.
Xerophytes, 114-118*.
Yarrow, head of, App. I, *359.
Yeast fungi, 244-246*.
Yucca, pollination of, *176, 177.
Zoospores, *226.
Zygospores, *221, *248.KEY AXI) FLORA
NORTHERN AND CENTRAL STATES
BY
JOSEPH Y. BERGEN, A AI.
REVISED axd exlarged
GIXX A COMPANY
BOSTON ■ NEW YORK CHICAGO LONDONCopyright, 1901, 1908
By JOSEPH Y. BERGEN
ALL RIGHTS RESERVED
812.2
IE t)t 9tl)tniium
GINN Si COMPANY • PRO-
PRIETORS ■ BOSTON • U.S.A.PREFACE
This flora is a considerably enlarged revision of the one pre-
pared by the author in 1901. It does not profess to describe
all the conspicuous seed plants of any locality, but rather to
comprise a large number of the most available spring-bloom-
ing species over an extensive region. More than a hundred
species have been added to the list included in the older
edition, mainly of plants which range westward to the moder-
ately high plains. The little book may therefore afford a
good deal of practice in the determination of species to sec-
ondary-school pupils in states even as far west as the Dakotas,
Nebraska, Kansas, and Oklahoma. It extends south about to
the southern boundary, of Kansas on the west and to that of
Virginia on the east.
In the matter of nomenclature it seems best for those who
do not wish to be hopelessly sectional to follow the rulings of
the Vienna Congress.' The author deems himself fortunate to
have been able in this connection to avail himself of the deci-
sions of the staff of the Gray Herbarium, as embodied in the
seventh edition of Gray’s .1 lanual of Botany, and to get advice
from the same source in regard to names of cultivated plants
not described in the Manual. His most sincere thanks are
hereby tendered for this invaluable assistance.
At the risk of sometimes seeming pedantic the writer has
adopted the practice of discarding, for the most part, such un-
scientific expressions as stemless plants,” •• radical leaves,”
“ calyx adnate to the ovary,” and several others. It is certain
that if the plant descriptions which contain such terms were
now being framed for the first time on the basis of present-
day morphology, these terms would not be used.
Most of the plants here described bloom before the end of
the school year, and it is believed that all of those which occur
toward the southern limits of the territory covered will be
found to flower there considerably before the end of June. It
iiiIV
KEY AND FLORA
may be found worth while, in the case of some Umbelliferce,
Boraginacew, and Composites, to collect fruit during the sum-
mer before it is to be used, preserve it either dry or in pre-
servative fluid, as may seem best, and use it with freshly
collected flowers in the determination of species.
No systematic work with seed plants can be of much use
unless the teacher takes constant pains to bring out the idea
of actual relationship by descent among the forms studied,
and to show, in the simpler cases available, some of the steps
of evolution. The beginner must not be allowed to suppose
that the flora which he is using contains more than a small
fraction of the total number of plants even in the families
treated. He must be made to realize that the Rubiacece, for
instance, of which he has fourteen species described, really
number as many as 4500 species, and the Compositce, instead
of mustering a few dozen strong, number in all at least 12,000
species. For such comparisons Engler’s Syllabus der Pflanzen-
familien will be found to contain the most recent and compact
summary.
A somewhat complete (phanerogamic) flora of the student’s
region should be constantly in use. For this purpose the
author prefers to all others the seventh edition of Gray’s
Manual of Botany. For the convenience of those who may
find it necessary to use Britton’s Manual of the Flora of the
Northern States and Canada, the generic name used by Britton
will generally be found in parenthesis after the name sanc-
tioned by the Vienna code. In cases where Britton’s genus
covers only part of the genus as given in this book, a state-
ment to that effect is made, as on p. 186,-—B. FI. species 4
(Naumburyia). For suggestions about literature see Bergen
and Davis, Laboratory and Field Manual of Botany, p. 230.
The novice should find a good deal of help in understand-
ing the structure of some of the more difficult flowers and
fruits in the illustrations which accompany several families.
Most of these have been redrawn for the present edition by
Mr. E. N. Fischer of Boston.
J. Y. B.
Cambridge, MassachusettsHOW TO USE THE KEY AND FLORA
In order to determine an unknown species, the student is
first to make a careful examination of the plant in hand.
After noting in a general way the appearance of the root,
stem, and leaf, including a cross section of the stem, he
should study the number of the parts of the flower, then
make and draw a cross section and a lengthwise section of it.
The kind of symmetry of the calyx and corolla, peculiarities
in the shape, structure, or operation of the essential organs,
such, for instance, as anthers discharging through chinks in
the end, should be noted.
Next, the inquirer should look carefully through the key
to the families. He is first to decide whether the plant in
question is a Gymnosperm or an Angiosperm ; if not a conif-
erous tree or shrub, it will of course belong to the latter
division. He is then to settle the question whether it is a
Monocotyledon or a Dicotyledon; then under what division
of the group the plant comes; and, finally, to decide upon its
family.
Turning now to the page at which the family is described,
a rapid inspection of the characteristics of the genera will
make it evident to which one the species under examination
belongs. It may not infrequently prove that none of the
genera described agree with the plant studied, and in that
case the student must either consult a larger flora or rest
satisfied with having determined the family to which his
specimen belongs. The identification of the species, after
12
KEY AND FLORA
the genus has been reached, presents no difficulty in a little
flora like the present one.
A single example may suffice to illustrate more in detail
the manner of determining species. Suppose the student to
have in hand a flowering specimen of lily of the valley. Turn-
ing to the key, page 5, it is evident from the statements con-
cerning Gymnosperms that the plant does not belong under
that head. Under Angiosperms it is clear, from the numerical
plan of the flower (in threes) and the parallel-veined leaves,
that the plant is a Monocotyledon. Among Monocotyledons
three general groups are designated by as many numbers in
parenthesis. The flower in hand belongs under (3) “ Flowers
not on a spadix.” Under this head the choice is first be-
tween (ft) “Carpels numerous and separate” and (b) “ Carpels
united.” In the lily of the valley they are united. The next
choice is between “ * Perianth hypogynous ” and “** Peri-
anth not hypogynous.” This flower is hypogynous. The
families with hypogynous perianth are grouped under three
'divisions (distinguished by f, tt, ttt respectively), and of
these the last, with its “ Perianth actinomorphic, its divi-
sions all alike or nearly so, petal-like,” corresponds to the
flower under examination and refers the student to “10. Lily
Family, page 6.” Turning to the key to the genera of the
Lily family, page 31, two subfamilies are found. Since the
plant is not a climber it belongs to “ Subfamily I. Lifiaceae
Proper.”
This subfamily is divided into five groups designated by
capital letters. The lily of the valley has an undivided style
and springs from a rootstock, therefore it belongs to group B.
Beading the descriptions under B, none is found to agree with
the plant in hand until the next to the last is reached : “ Leaves
only 2, directly from the rootstock. Flowers in a raceme, bell-
shaped, white, sweet-scented, Convallaria.”HOW TO USE THE KEY AND FLORA
B
Referring now to the genus, it is found that there is only-
one species and that one agrees with the specimen in hand.
It is therefore Convallaria majalis, and the name (as indi-
cated by the L. which follows it) was given by the great
Swedish naturalist, Linnaeus.1
The author does not believe in spending much of the school
time of a class upon identifying species, but would rather
recommend comparative studies of as many plants of a group
as are accessible, and making these studies thorough enough
to bring out fully the idea of the family, the genus, and the
species.2 The descriptions in this flora may be used as a
check on the cruder ones which the pupil is first to frame for
himself.
1	It will greatly simplify matters if the teacher throughout selects for
examination only such species as are described iu the flora.
2	The teacher will find abundant suggestions for such a course in Spalding’s
Introduction to Botany, pp. 152-260.KEY TO THE FAMILIES OF FLOWERING PLANTS
DESCRIBED IN THIS FLORA
CLASS I
GYMNOSPERMS. Ovules not inclosed in an ovary.
Trees or shrubs. Leaves usually evergreen and needle-shaped, awl-shaped,
or scale-like. Flowers monoecious or dioecious. Fruit a scaly cone, or
sometimes appearing berry-like.	1. Pine Family, page 13
CLASS II
ANGIOSPERMS. Ovules inclosed in an ovary.
SUBCLASS I. — MONOCOTYLEDONS. Flowers usually with their
parts in threes, never in fives. Leaves usually parallel-veined. Cotyledon 1.
(1)	Flowers inclosed by chaffy bracts.	Family	Page
Flowers 2-bracted. Leaves 2-ranked. Stem cylin-
drical.	.	.	.	.	.... 4. Grass .	.	. 22
Flowers 1-bracted. Leaves 3-ranked. Stem trian-
gular .	...	.	.	.	.5. Sedge .	.	.23
(2)	Flowers on a spadix.
Spadix slender, hairy, and bristly .	2. Cat-Tail .	20
Spadix fleshy................... 6. Arum .	.	.24
(3)	Flowers not on a spadix.
(а)	Carpels usually numerous and nearly or entirely
separate .	...................... .3. Water Plantain . 21
(б)	Carpels united.
* Perianth hypogynous or nearly so.
t Perianth actinomorphic, its parts similar, green,
or chaffy .	.	.............9. Rush. .... 30
11 Perianth of 2 sets, one sepal-like, the other petal-
like.
Style and stigma 1. Petals 3 or 2, soon disap-
. 7. Spiderwort .	. 26
pearing .6
KEY AND FLORA
Styles or stigmas 3, separate. Petals 3, lasting		Family	Page
several days. Leaves netted-veined	10.	(Trillium) Lily	. 30
Style 1, stigma 3-lobed or 6-toothed. Corolla not actinomorphic. Aquatic herbs			
with parallel-veined leaves	8.	Pickerel Weed	. 28
111 Perianth actinomorphic, its divisions all alike			
or nearly so, petal-like .	10.	Lily	30
* * Perianth not hypogynous.			
Anthers 6	11.	Amaryllis	43
Anthers 3	12.	Iris	. 45
Anthers 1 or 2	13.	Orchis . .	. 47
SUBCLASS II. — DICOTYLEDONS. Flowers usually with their parts in
fives or fours. Leaves netted-veined. Cotyledons 2.
I. Apetalous Division. Flowers without a corolla or without either calyx or
corolla.1
A
Flowers monoecious or dioecious, one or both
sorts in catkins.
(1)	Staminate flowers in catkins, the pistillate ones
solitary or clustered.
Leaves pinnately compound .	.	16. Walnut .	.	52
Leaves simple ...	18. Beech....	58
(2)	Both kinds of flowers in catkins.
(a) Leaves alternate.
Ovaries in fruit becoming fleshy and com-
bining into an aggregate fruit .	20.	Mulberry	.	.	64
Fruit 1-seeded, a drupe or minute nut.
Aromatic shrubs ...	...	15.	Bayberry	.	51
Fruit a capsule, seeds with silky hairs .	14. Willow .	48
Fruit a minute nut or akene. Mostly large
shrubs or trees, not very aromatic . 17. Birch .	.	54
(&) Leaves opposite, small parasitic shrubs .	.	23.	Mistletoe .	.	68
B
Flowers not in catkins, both calyx and co-
rolla wanting .	.	. 45. Sycamore .	113
1 When only one floral envelope is present, this is said to be the calyx and
the corolla is considered to be missing.KEY
7
Flowers not in catkins; calyx present, sometimes petal-like. (1) Trees or shrubs. Flowers not hypogynous ; plants not climbing .	74.	Family Page Dogwood . 175	
Flowers not hypogynous ; climbing plants	24.	Dutchman’s Pipe	68
Flowers hypogynous. Style single, not cleft, fruit a key (Fraxinus)	79.	Olive . .	189
Style single, not cleft, fruit a drupe	38.	Laurel	95
Styles 2 or 2-cleft, fruit 1-celled	19.	Elm.	62
Styles 2 or 2-cleft, fruit 2-celled	59.	Maple . .	151
Styles 3, each 2-cleft. Ovary 3-celled	54.	Spurge .	145
(2) Herbs. Flowers not hypogynous ; ovary 6-celled	24.	Dutchman’s Pipe	68
Flowers not hypogynous ; ovary 1-celled ; flowers in umbel-like clusters ... . .	22.	Sandalwood	67
Flowers hypogynous. (a) Ovary 1-celled. Stamens many		33.	Buttercup . .	83
Stamens few. Stipules sheathing the joints	25.	Buckwheat	69
Stipules wanting. Rather fleshy herbs 		26.	Ooosefoot	72
Not fleshy. Ovules on a free central placenta; deli- cate, soft-leaved herbs. (Stellarin) .	31.	Pink .	17
Ovule single, coarse herbs .	27.	Amaranth.	74
(b) Ovary several-celled. Small prostrate herb ; leaves spatulate, whorled	29.	Ice Plant	76
Stipules present, not sheathing. Style single	21.	Nettle .	66
Styles 2 		20.	Mulberry . .	64
Flowers hypogynous, ovary 3-celled	54.	Spurge . .	145
Flowers hypogynous, ovary 5-10-celled; fruit a berry		28.	Pokeweed .	758
KEY AND FLORA
II. Choripetalous Division. Calyx and corolla both present, the petals not united.
A
Stamens more than 10. (1) Trees, shrubs, or woody vines. (a) Leaves alternate. * Ovary 1, simple. Fruit a drupe ....	Family 46. Rose . . .	Page . 113
* * Ovary 1, compound; fruit dry. Ovary 5-celled, 1-2-seeded at maturity	64. Linden . . .	. 157
Ovary 3-celled, many-seeded .	69. Begonia . .	. 164
*** Ovary 1, compound; fruit fleshy	46. Rose .	. 113
**#* Ovaries numerous. t Leaves with stipules. Stamens inserted on the receptacle	35. Magnolia . .	. 92
Stamens many, monadelphous	65. Mallow. . .	. 158
Stamens inserted on the calyx	46. Rose . .	113
ft Leaves not with stipules. Small trees .	37. Papaw . . .	. 94
(6) Leaves opposite ; fruit dry. Ovary single, 3-5-cel led	44. Saxifrage . .	109
Ovaries several, inclosed by the calyx tube	36. Calycantkus .	. 94
(2) Herbs. (a) Ovary single, simple ; fruit a berry	34. Barberry . .	91
(b) Ovaries several, simple. Stamens inserted on the receptacle	33. Buttercup . .	83
Stamens inserted on the calyx .	46. Rose	. 113
(c) Ovary compound. Aquatic herbs, leaves flat . ....	32. Water Lily .	. 82
Marsh herbs, leaves tubular	43. Pitcher Plant	. 108
Terrestrial herbs. * Ovary 1-celled. Placentas central, juice watery	30. Purslane .	76
Placentae parietal, juice milky or colored	39. Poppy . . .	96
Placentae 2, parietal . ...	41. Caper . . .	. 107
Placentae 3 or more, parietal. Leaves alternate . . ...	42. Mignonette	. 108
Leaves opposite	66. St. John’s-wort	160
Leaves apparently wanting; stems fleshy	70. Cactus .	. 166
* * Ovary several-celled; stamens monadelphous	65. Mallow. . .	. 158
*** Ovary 3-celled; stamens not much if at all monadelphous; stems fleshy, juice acid .	69. Begonia . .	. 164KEY
9
B
Stamens not more than 10.
(1)	Trees, shrubs, or woody vines.
(а)	Fruit a drupe.
Stamens 2, rarely 3-4	.	...
Stamens as many as the petals.
Flowers bisexual.
Stamens 4, alternate with the petals
Stamens 5, alternate with the petals
Stamens 4-5, opposite the petals .
(б)	Fruit a berry.
Stamens alternate with the petals.
Inserted on the calyx, leaves simple
Inserted on a disk surrounding the ovary;
leaves compound .	...
Stamens opposite the petals .	.	.
(c)	Fruit a 2-seeded capsule or a key.
Leaves compound
(d)	Fruit a 2-celled, many-seeded capsule; flowers
large, yellow .	....
(e)	Fruit a 3-5-celled capsule; flowers small, green-
ish, or brown-purple; leaves simple .
(/) Fruit 5-lobed, the 5 carpels separat ing when ripe;
flowers rather large, white, or of showy colors;
leaves simple .	...	.	.
(g)	Fruit a 1-3-celled capsule, leaves compound,
flowers zygomorphic
(h)	Fruit a 3-celled bladdery capsule, leaves com-
pound, flowers actinomorphic
(i)	Fruit a legume ....	.	.
(2)	Herbs.
(a) Ovary single, 1-celled, simple or compound.
* Corolla actinomorphic or nearly so.
Sepals and petals 4-5; stamens 5,10, or 12,
distinct.
Leaves alternate.
Stigma single .	.	.
Stigmas 4 or 2	.	...
Leaves opposite, punctate, flowers yellow .
Leaves opposite, flowers white or red
Sepals and petals 4-5; stamens 5, united .
Sepals 2, petals 4-5.......................
Family	Page
79. Olive . .	. 189
74. Dogwood . .	. 175
55. Sumac . .	. 148
62. Buckthorn	. 154
44. Saxifrage .	. 109
72. Ginseng . .	. 169
63. Grape or Vine	155
52. Rue . .	144
79. Olive . . .	189
57, Wahoo . . .	. 150
48. Geranium .	140
60. Buckeye .	152
58. Bladder Nut	. 151
47. Pea or Pulse .	. 126
47. Pea or Pulse .	126
44. Saxifrage .	.	. 109
66. St. Jobn’s-wort . 160
31. Pink .	.	77
68. Passion Plower . 163
30. Purslane ...	7610
KEY AND FLORA
Sepals 6, stamens hypogynous, opposite the
petals...................................
** Corolla zygomorphic.
Fruit a legume ...	....
Fruit a capsule.
Stamens 5	.	..................
Stamens 6, in 2 sets ....	.
(&) Ovary single, 2-5-celled, fruit usually dry.
* Ovary 2-celled (or 2 carpels nearly separate).
Flowers in umbels, stamens 5	...
Flowers not in umbels, petals 4 or 0, stamens 6
Flowers not in umbels, petals 5, stamens 10 .
Flowers not in umbels, petals 3, stamens 6 or 8
* * Ovary a 4-celled capsule .	.	....
#** Ovary of 3 nearly distinct lobes, which become
thick and fleshy in fruit ....	.
**** Ovary a5-celled capsule,
t Leaves simple.
Parasitic white or yellowish herbs, or ever-
green herbs, not parasitic, capsule many-
seeded .	...
Terrestrial, not much if at all fleshy, capsule
5-10-seeded .	.....................
Terrestrial, stem fleshy and translucent, cap-
sule elastic, several-seeded .
tt Leaves of 3 leaflets .
(c)	Ovary of 5 principal cells, each more or less divided
by a partition into 2 cells; seeds flattish, with a
mucilaginous coating...................
(d)	Ovary single, 2-5-celled ; fruit a berry
(e)	Ovaries 2, seeds hairy-tufted
Family	Page
	. 91
47. Pea or Pulse .	. 126
67. Violet . . .	161
39. Poppy .	. 96
73. Parsley . .	170
40. Mustard . .	99
44. Saxifrage . . .	109
53. Polygala	145
71. Evening Primrose	168
50. Indian Cress . .	142
75. Pyrola . .	. 177
	. 140
61. Balsam. . .	. 153
49. Wood Sorrel .	142
51. Flax . . .	143
72. Ginseng	. 169
82. Milkweed .	194
III. Sympetalous Division. Calyx and corolla both present, the petals appearing
more or less united.
(1) Trees, shrubs, or woody vines.
(a) Leaves alternate.
* Fruit splitting open.
Fruit a legume...........................47. Pea or Pulse .	146
Fruit a 5-celled capsule .	.... 76. Heath .... 179
** Fruit not splitting open, a drupe............66. Holly .... 149
*** Fruit a berry.KEY		11
	Family	Page
Ovary superior; seeds few, large	78. Ebony . .	. 188
Ovary superior; seeds many, small .	89. Nightshade	. 214
Ovary inferior	76. Heath	. 179
(b) Leaves opposite. * Fruit a 2-celled, 2-seeded capsule	95. Madder	. 227
* * Fruit a 2-celled, many-seeded capsule. Seeds large, winged	91. Bignonia . .	222
Seeds not winged except in Diervilla; slirubs	96. Honeysuckle .	230
* * * Fruit a 5-celled capsule .	76. Heath .	. 179
* * * * Fruit a drupe or berry. Fruit 1-2-seeded (in Forsythia many-seeded); stamens 2	79. Olive	189
Fruit 1-4-seeded; stamens 4	87. Verbena	. 207
Fruit 1-5-seeded; stamens 5	96. Honeysuckle .	. 230
(2) Herbs. (a) Ovary superior, flowers regular. * Ovary separating into 2 distinct follicles. Style single, stamens distinct	81. Dogbane . .	192
Styles 2, stamens united. . ...	82. Milkweed .	194
** Ovary 1-celled. Fruit a legume . ....	47. Pea or Pulse	'126
Fruit a capsule. Leaves alternate. Stamens opposite the lobes of the corolla	77. Primrose	co
Stamens alternate with the lobes of the corolla . . ...	85. Waterleaf . .	. 201
Leaves opposite	80. Gentian	191
Leaves all reduced to mere scales, plants never green, root parasites	92. Broom Rape .	223
* * * * Ovary 2-several-celled. Stamens 2 or 4 .	94. Plantain	. 225
Stamens 5, cells of the ovary 1-2-seeded. Fruit separating into 4 nutlets	86, Borage .	203
Fruit a capsule	83. Morning-Glory	197
Stamens 5, cells of the ovary several-seeded. Stigma 1 . ...	89. Nightshade	214
Stigmas 3 . . .	84. Phlox .	199
(6) Ovary superior, flowers zygomorphic. * Ovary 1-celled. Fruit a legume . ... ...	47. Pea or Pulse .	12612
KEY AND FLORA
* * Ovary 2-4-celled. t Cells each 1-seeded. Ovary deeply 4-lobed ...	00 00	Family Mint . .
Ovary not deeply lobed. Stamens 2 or 4 		87.	Verbena .
Stamens 8 . . .	. . 53.	Polygala .
11 Cells each 2-several-seeded. Corolla lohes imbricate in the bud	90.	Figwort
Corolla lobes convolute in the bud	93.	Acanthus .
(c) Ovary inferior. Flowers in an involucrate head .	. 100.	Composite
Flowers not in heads. Stamens 3. Leaves opposite	. 97.	Valerian .
Leaves alternate . ...	98.	Gourd .
Stamens 4-5. Leaves alternate . ....	. . 99.	Campanula
Leaves opposite or whorled .	. . 95.	Madder
Page
209
. 207
. 145
. 217
. 224
. 239
235
. 236
. 237
. 227CLASS I. GYMNOSPERMS
Plants destitute of a closed ovary, style, or stigma. Ovules
generally borne naked on a carpellary scale, which forms part
of a cone. Cotyledons often several (Pig. 1).
1. PINACE-ffi. Pine Family
Trees or shrubs with wood destitute of ducts, with resinous
and aromatic juice. Leaves generally evergreen, and needle-
shaped or awl-shaped. Flowers destitute of floral envelopes,
monoecious or dioecious, the staminate ones consisting of
catkin-like spikes of stamens and the pistillate ones consist-
ing of ovule-bearing scales, arranged in spikes, which ripen
into cones.
A
Each scale of the cone borne in the axil of a bract. Seeds 2, with tvitigs.
Leaves evergreen, in bundles of 2-5.	Pinus, I
Leaves evergreen, solitary, sessile, keeled on both surfaces.
Picea, II
Leaves evergreen, solitary, petioled, flat.	Tsuga, III
Leaves solitary, evergreen, flat above, keeled below. Abies, IV
Leaves clustered, deciduous, flat.	Larix, V
B
Scales of the cone without bracts, cone becoming globular and woody.
Leaves linear.
Leaves alternate, deciduous.	Taxodium, VI
1 O
lo14
KEY AND FLORA
C
Scales of the cone few, without bracts. Leaves evergreen, generally scale-
like or awl-shaped.
Sterile flowers somewhat resembling inconspicuous catkins,
borne at the base of the young shoot of the season, each flower
consisting of pollen-scales in spiral groups (Fig. 1, 2). Fertile
flower spikes consisting of spirally arranged carpel scales, each
scale springing from the axil of a bract and bearing at its own
base two ovules (Fig. 1, 3). Fruit a cone, formed of the thick-
ened carpellary scales, ripening the second autumn after the
flower opens. Primary leaves, thin and chaffy bud scales, from
the axils of which spring the bundles of 2-5 nearly persistent,
needle-like, evergreen leaves, 1-15 in. long (Fig. 1).
1.	P. Strobus L. White Pine. A tall tree, 75-160 ft. high, much
branched and spreading when growing in open ground, but often-
with few or no living branches below the height of 100 ft. when
growing in dense forests. Leaves clustered in fives, slender, 3-4 in.
long, smooth and pale or with a whitish bloom. Cones 5-6 in. long,
not stout. The wood is soft, durable, does not readily warp, and is
therefore very valuable for lumber. In light soil, commonest N.
2.	P. Taeda L. Loblolly Pine, Oldfield Pine. A large tree ;
bark very thick and deeply furrowed, becoming flaky with age; twigs
scaly. Leaves in threes, 6-10 in. long, slender, very flexible; sheaths
f-1 in. long. Cones solitary, oblong-conical, 3-5 in. long; scales
thickened at the apex, the transverse ridge very prominent and
armed with a short, stout, straight or recurved spine. Common, and
often springing up in old fields; trunk containing a large proportion
of sapwood; timber of little value for outside work.*1
3.	P. rigida Mill. Northern Pitch Pine. A stout tree, 30-80 ft.
high, with rough, scaly bark. Leaves in threes, 3-5 in. long, stiff and
flattened. Cones ovoid-conical, 2-3 in. long, their scales tipped with
a short, abruptly curved spine. Wood hard, coarse, and resinous,
mainly used for fuel. Poor, sandy soil, especially eastward.
1 Descriptions followed by an asterisk are taken (more or less simplified)
from Professor Tracy’s flora in the Southern States Edition.
Cones dry and thin-scaled.
Cones berry-like.
Thuja, VII
Juniperus, VIII
1. PINUS L.PINE FAMILY
15
4. P. virginiana Mill. Scrub Pine. A small tree, usually 20-30 ft.
high, but sometimes much taller; bark of the trunk w5ugh, nearly
black; twigs smooth and with a bloom. Leaves in twos, 1-2 in.
1, a twig showing: a, stamiuate catkins; b, pistillate catkins; c, a cone; <?,
needles. 2, an anther: a, side view; b, outer surface. 3, a carpel scale:
a, inner surface; b, outer surface. 4, a a cone scale, 6 a seed wing, and
c a seed. 5, section of a seed, showiug the embryo. 1 is natural size;
parts 2, 3, and 5 are magnified by the'amount indicated by comparison
with the vertical line alongside each. (After Wossidlo)
long, rigid, sheaths very short. Staminate catkins dull, yellowish-
purple, 1 in. long. Cones solitary, short-peduncled, often reflexed,
ellipsoid-conic, about 2 in. long; scales thickened at the apex and16
KEY AND FLORA
armed with a slender, straight or recurved prickle. On dry, sandy
soil; wood light, soft, weak, and of little value.*
5.	P. sylvestris L. Scotch Pine (wrongly called Scotch Fir). A
medium-sized tree, with the older bark reddish and scaly. Leaves in
twos, 11-21 in. long. Cones rather small and tapering (Fig 1, 1, c).
Cultivated from Europe.
6.	P. resinosa Ait. Red Pine, Norway Pine. A tall, rather
slender tree, with bark reddish-brown and moderately smooth.
Leaves in twos, slender, and 5-6 in. long. Cones borne at the ends
of the branches, smooth, about 2 in. long. A valuable timber tree,
which often grows in small, scattered clumps; wood firm, pale red,
and not very resinous; us.ed in house and bridge building, and for
masts and spars.
7.	P. palustris Mill. Long-Leaved Pine. A large tree ; bark
thin-scaled, wood very resinous, old trees with only a few spreading
branches near the top. Leaves in threes, 10-15 in. long. Sheaths
1-1J in. long, crowded near the ends of very scaly twigs. Staminate
catkins 2-3 in. long, bright purple, conspicuous. Cones terminal,
ellipsoid-conical, 6-10 in. long, diameter 2-3 in. before opening, 4-0
in. when fully opened; scales much thickened at the apex and armed
with a short recurved spine at the end. The most common tree in the
pine barrens; wood hard, strong, and durable, especially valuable for
floors and inside work.*
H. PICEA Link
Sterile flowers generally axillary (sometimes terminal),
borne on the twigs of the preceding year. Fertile flowers
terminal. Fruit a nodding, thin-scaled cone, ripening in the
first autumn. Leaves evergreen, needle-shaped, four-angled,
scattered or spirally arranged.
1.	P. mariana BSP. Black Spruce. A small tree, usually only
20 or 30 ft. high, often less. Leaves strongly 4-angled, bluish-green,
and glaucous, J-J in. long. Cones ovoid, pointed, ^-1} in., usually
about 1 in. long, persisting sometimes for 20-30 years. Wood of
little value except for paper pulp. The tree is especially abundant
northward and is of common occurrence in peat bogs.
2.	P. rubra Dietrich. Red Spruce. A large tree, 70-80 or even
100 or more feet high, of strict conical habit. Leaves dark green or
yellowish and glossy, t-f in. long. Cones ovoid-oblong, acute, usually
1^-2 in. long, mostly falling the first year. This is the principal
timber spruce of the northeastern United States, and furnishes much
rather tough lumber for use in floor joists, scantling, and similar
purposes.PINE FAMILY
17
3.	P. canadensis BSP. AVhite Spruce, Skunk Spruce, Cat
Spruce. A tall, rather conical tree, 00-70 ft. high. Leaves pale and
with a bloom sometimes | in. long. Cones cylindrical, with rounded
ends, about 2 in. long, failing inside of one year. A handsome tree,
valuable for timber, ranging far northward.
4.	P. Abies Ivarst. Norway Spruce. A large tree. Leaves dark
green, ;f-l in. long. Cones 5-7 in. long. Cultivated from Europe.
in. TSUGA Carriere
Sterile flowers, clusters of stamens springing from the axils
of leaves of the preceding year. Cones terminal, on twigs of
the preceding year, drooping, thin-scaled, ripening the first
year. Leaves minutely petioled, short, flat, white beneath,
2-ranked.
1. T. canadensis Carriere. Hemlock. A large tree, in age branch-
less below when growing in dense woods. When young the spray is
very graceful and abundant. Leaves short-linear. Cones } in. or
less in length. The wood is coarse and splintery, but useful for
fences and other rough work. The thick reddish bark is of great
value for tanning.
IV. ABIES Hill
Sterile flowers from axils of leaves of the preceding year.
Cones erect, on the sides of the branches, with deciduous
scales, ripening the first year. Leaves scattered, but on hori-
zontal branches appearing 2-ranked, flat above, silvery, and
with a prominent midrib below.
1. A. balsamea Mill. Balsam Fir. A slender tree, 50-60 ft.,
occasionally 80 ft., high, with dense foliage. Leaves narrowly linear,
less than 1 in. long. Cones violet-colored until old, cylindrical, 2-4
in. long. The bark contains many large blisters, filled with the well-
know Canada balsam. The wood is brittle and of little value.
V. LARIX Mill.
Flower spikes short, opening in early spring, before the
leaves ; the fertile ones, while still young, of a beautiful crim-
son color. Fruit a small cone, with thin scales. Leaves none
of them Scaly, but all needle-shaped, soft, deciduous, very
numerous, in little brush-like bundles.18
KEY AND FLORA
1.	L. laricina Koch. American Larch, Tamarack, Hackma-
tack (wrongly, but quite generally, called Cypress and Juniper).
A tall, slender tree, 30-100 ft. high. Leaves slender and less than
1 in. long-, very pale bluish-green. Cones -|-| in. long, few-scaled.
Wood hard, tough, and heavy, of considerable use for shipbuilding.
2.	L. decidua Mill. European Larch. Leaves bright green and
longer. Cones longer than in the preceding species and many-scaled.
Cultivated from Europe.
VI. TAXODIUM Richard
Trees. Leaves spreading so as to appear 2-ranked, decidu-
ous. Flowers monoecious, appearing before the leaves ; stami-
nate ones numerous, globose, forming long, terminal, drooping,
panicled 'spikes; anthers 2-5-celled. Pistillate flowers single
or in pairs, bractless., the peltate scales 2-ovuled. Cone globose ;
the very thick -woody scales angular, separating at maturity.
Seeds 3-angled, pyramidal.*
1. T. distichum Richard. Bald Cypress. A very large tree ; bark
dark brown, rough, fibrous; many of the twigs deciduous with the
leaves. Leaves alternate, opposite, or whorled, 2-ranked, flat, linear,
in. long. Cones terminal, globose, about 1 in. in diameter; ends
of the scales much thickened, wrinkled, and with a distinct trian-
gular marking. Common in swamps and on the borders of streams;
wood reddish, soft, light; specially valued for shingles and fence
posts, and for boat building.*
VII. THUJA L.
Flowers small, terminal, monoecious, on different branches.
Stamens each consisting of a scale-like portion bearing 4
anther-like cells. Pistillate flowers consisting of a few overlap-
ping scales which ripen into a small, loose cone. Leaves ever-
green, opposite, and closely overlapping on the stem, of two
kinds, those on the more rapidly growing twigs awl-shaped,
the others mere scales.
1. T. occidentalis L. Arbor Vit.e, Cedar. A small tree, 20-50
ft. high, with soft, fibrous bark. Leaves mostly awl-shaped and blunt.
Cones ellipsoidal, their scales 2-seeded. (trows on rocky ledges, but
reaches its greatest size in cool cedar swamps. Wood soft, yellowish,
fragrant, durable, prized for shingles and fence posts.PINE FAMILY
19
vni. JUNIPERUS L.
Flowers very small, lateral, dioecious, or sometimes monoe-
cious. Scales of the staminate flower shield-shaped, with 3-6
anther cells. Fertile flowers with 3-6 fleshy scales which
unite into a berry-like, 1-3-seeded fruit. Leaves awl-shaped
or scale-shaped.
1.	J. communis L. Juniper. A low, spreading shrub (one variety
prostrate in circular masses). Leaves linear-awl-shaped, with needle-
like points, each marked with a distinct stripe of bloom along the
center of the upper surface, borne in whorls of three. Fruit a dark
blue aromatic berry, } in. or more in diameter. Grows in dry pas-
tures and on sterile hillsides N.
2.	J. virginiana L. Red Cedar, Savin. Ranges in size and
shape from a low. rather erect shrub, to a conical tree 90 ft. high.
Leaves of two kinds, those on the rapidly growing shoots awl-shaped
and pointed, those on the shortest twigs scale-shaped, obtuse, or
nearly so, and closely appressed to the stem. Fruit small, bluish,
with a white bloom. Found all the way from British America to
Florida. "Wood soft, fragrant, reddish, exceedingly durable in the
ground, valued for the manufacture of moth-proof chests and espe-
cially for lead pencils.20
KEY AND FLORA
CLASS II. ANGIOSPERMS
Plants with a closed ovary, in which the seeds are matured.
Cotyledons 1 or 2.
SUBCLASS I. MONOCOTYLEDONOUS PLANTS
Stems with the fibrovascular bundles scattered among the
parenchyma cells ; in perennial plants no annual rings of wood.
Leaves usually parallel-veined, alternate, nearly always entire.
Parts of the flower generally in threes (never in fives). Coty-
ledon 1.
2. TYPHACEjE. Cat-Tail Family
Perennial marsh or aquatic plants. Rootstock stout, creep-
ing ; stem simple, cylindrical, erect. Leaves simple, strap-
shaped, sheathing at the base, nerved and striate. Flowers
monoecious, in a single terminal spike, staminate part of the
spike uppermost, each part subtended by spathe-like deciduous
bracts. Perianth of fine bristles. Staminate flowers sessile,
stamens 2-7; filaments connate, subtended by minute bracts.
Pistillate flowers short-pediceled. Ovary 1-2-celled; styles
1-2. Fruit small, nut-like.*
TYPHA L.
Characters of the family.
1. T. latifolia L. Cat-Tail. Stem erect, jointed below, 5-"8 ft.
high. Leaves nearly as long as the stem, about 1 in. wide, netted
and with a bloom. Spike cylindrical, dark brown or black; staminate
portion above the pistillate, usually without any interval between
them, each 4-8 in. long and about 1 in. in diameter. Fruit furrowed.
Common in marshes and shallow ponds.*WATER PLANTAIN FAMILY
21
3. ALISMACEJE. Water Plantain Family
Annual or perennial marsh herbs, usually with creeping run-
ners or rootstocks. Stems scape-like. Leaves long-petioled,
sheathing at the base ; petiole rounded ; blade nerved, netted,
or sometimes wanting. Flowers in racemes or panicles, bisex-
ual, monoecious or dioecious ; pedicels in bracted whorls. Sepals
3, persistent; petals 3 or wanting. Stamens 6 or more. Ovaries
few or many, 1-celled, 1-seeded; style short or none. Fruit a
1-seeded akene.*
I. SAGITTARIA L
Perennial; rootstocks mostly knobby or tuber-bearing.
Scapes erect or decumbent. Leaves long-petioled, sheathing
at the base, the blade round and netted, or wanting. Flowers
monoecious or dioecious, racemed in 3-bracted whorls of threes,
the upper flowers usually staminate. Sepals 3, persistent;
petals 3, withering-persistent or deciduous. Stamens few or
many. Ovaries in globose heads, 1-ovuled; style short, per-
sistent. Fruit a subglobose head of flattened akenes.*
1.	S. latifolia Willd. Broad-Leaved Arrowhead. Leaves very
variable in size and shape, from broadly sagittate to linear, those
growing on the drier soil being usually the broader; petioles 6-30
in. long. Scape smooth or slightly downy. 6-36 in. high ; bracts
acute. Flowers monoecious or sometimes dioecious, white, 1 in. or
more in width; pedicels of the staminate flowers twice the length of
those of the fertile flowers. Filaments long', smooth, and slender.
Akenes with beak nearly horizontal. Ditches and muddy places.*
2.	S. graminea Michx. Grass-Leaved Sagittaria. Leaves
long-petioled, lanceolate, or elliptical, and acute at each end, 3-5-
nerved, or often linear, the earlier often reduced to flattened petioles.
Scape slender, usually longer than the leaves, simple, weak, often
prostrate in fruit; bracts small, ovate, connate at the base. Flowers
monoecious or dioecious, on long, thread-like pedicels, about i in. wide.
Stamens 10-20, filaments downy. Akenes nearly beakless. In ditches
and shallow pools.*
H. ALISMA L.
Annual or perennial herbs. Leaves erect or floating, blades
prominently ribbed and netted, or even pinnately veined.22
KEY AND FLORA
Scapes erect, becoming longer than the leaves, cylindrical,
spongy. Flowers bisexual, in paniculate, 3-bracted umbels,
small, white or pink.
Fir.. 2. Diagrammatic
representation of a
several-flowered
grass spikelet
Stamens 6-9. Ovaries
numerous in one or more
whorls on a flat recepta-
cle. Fruit 1-seeded akenes
which are ribbed on the
back and sides.*
1. A. Plantago-aquatica L.
Water Plantain. Peren-
nial ; root fibrous. Leaves
ovate or somewhat cordate,
5-7-nerved when erect, float-
ing leaves narrower and
sometimes linear. Scapes
usually single; panicle 1-2
ft. long ; flowering branches
whorled, subtended by three
narrow, striate bracts; pedi-
cels slender, elongated. Ova-
ries 15-20 in a single whorl;
base of the short style per-
sistent, forming a beak at
the inner angle of the akene.
Akenes obliquely obovate,
2-3-keeled on the back.
Common in ponds and
muddy places.*
,9, the glumes; p,
p', the palets; l, Iod-
icules; /, a flower.
The axis is much
lengthened, to sep-
arate the flowers.
(After Schimper)
Fig. 3. Spike-like
panicle of ver-
nal grass (An-
thoxnnthum)
GRAMINEiE.
Family
Grass
a, mature anthers.
(Slightly enlarged)
Mostly herbs, with usu-
ally hollow stems, closed
and enlarged at the nodes.
Leaves alternate, in two ranks, with sheathing bases, which
are split open on the side opposite the blade. Flowers nearly
or quite destitute of floral envelopes, solitary, and borne in
the axils of scaly bracts, which are arranged in two ranksSEDGE FAMILY
23
overlapping each other on 1-many-flowered spikelets; these
are variously grouped in spikes, panicles, and so on. Fruit
Fig. 4. Vernal grass (Anthoxanthum)
A, a one-flowered spikelet: a, b, the outer empty glumes. B, a spikelet with the
outer glumes removed: c, c, the inner empty glumes (neuter flowers) with
long, bristle-shaped appendages; 0, e, palets; anth., anthers; stiff., stigmas.
<', diagram of cross section of a spikelet: a, glume; d, palet. D, a fruit.
(All magnified.) (After Cosson and De Saint-Pierre)
a grain. (The family is too difficult for the beginner, but the
structure and grouping of the flowers may be gathered from a
careful study of Tigs. 2, 3, 4.)
5. CYPERACE^E. Sedge Family
Grass-like or rush-like herbs, with solid, usually triangular,
stems, growing in tufts. The sheathing base of the generally
3-ranked leaves, when present, is not slit as in grasses. The
flowers are usually somewhat less inclosed by bracts than
those of grasses; the perianth is absent or rudimentary;
stamens generally 3; style 2-cleft or 3-cleft.24
KEY AND FLORA
The flower cluster and. the flower of a sedge may be under-
stood from an inspection of Fig. 5.
The species are even more difficult to determine than those
of grasses.
Fig. 5. Inflorescence, flower, and seed, of a sedge
(Great Bulrush, Scirpm lacustris)
A, magnified flower, surrounded by a perianth of hypogynous bristles; B, the
seed; C, section of the seed, showing the small embryo inclosed in the base
of the endosperm. (After Lindley)
6. ARACEiE. Ahum Family
Perennial herbs, with pungent or acrid juice. Leaves often
netted-veined. Small, unisexual or bisexual flowers, clusteredARUM FAMILY
25
along a peculiar fleshy spike called a spadix, and frequently
more or less covered by a large, hood-like bract called a spathe.
Perianth, when present, of 4-6 parts; often wanting. Fruit
usually a berry.
I. ARIS./EMA Martins
Perennial herbs, springing from a corm or a tuberous root-
stock. Spathe rolled up at base. Summit of spadix naked, the
lower part flower-bearing; staminate flowers above, pistillate
ones below. Stigma flat. Ovary 1-celled. Berry 1-few-seeded.
1.	A. triphyllum Schott. Indian Turnip, Jack-in-the-Pulpit.
Leaves generally 2, each of 3 elliptical-ovate, pointed leaflets. Spadix
club-shaped, bearing usually only one kind of fully developed flowers;
that is, full-sized pistillate and rudimentary staminate ones, or the
reverse. Spathe much longer than the spadix, and covering it like a
hood. Corm turnip-like, but much wrinkled, very starchy, and filled
with intensely burning juice.
2.	A. Dracontium Schott. Green Dragon, Dragon Root. Leaf
usually single, divided into 7-11 rather narrow, pointed leaflets;
spadix tapering to a long, slender point, often bearing fully developed
staminate and pistillate flowers.
II. SYMPLOCARPUS Salisb. (SPATHYEMA)
Rootstock very stout, with many long, cylindrical roots.
Leaves clustered, very large, and entire. Spathe shell-shaped,
very thick. Spadix globular, thickly covered with bisexual flow-
ers. Sepals 4. Stamens 4. Style 4-angled. Fruit globular or
ellipsoidal, with the seeds slightly buried in the enlarged spadix.
Coarse, stemless herbs, with a powerful scent like that of
the skunk and of onions.
1. S. fcetidus Nutt. Skunk Cabbage. Leaves many, slightly
petioled, 1-2 ft. long, appearing after the flowers. The latter are
usually seen before the ground is wholly free from frost, often earlier
than any other flower. Bogs and wet meadows, very common N.
in. ACORUS L.
Rootstocks horizontal, long, and moderately stout, aromatic.
Leaves long, upright, sword-shaped. Spathe much like the26
KEY AND FLORA
leaves. Spadix projecting from the edge of the spathe, con-
sisting of numerous bisexual flowers. Sepals 6. Stamens 6.
Ovary 2-3-celled, with numerous ovules. Fruit 1-few-seeded.
Fig. 6. Acorus Calamus
A, spadix; B, a single flower, enlarged; C, diagram of flower, enlarged.
(After Schimper)
1. A. Calamus L. Sweet Flag. Scape with a long, leaf-like pro-
longation (spathe) beyond the green, very closely flowered spadix.
Along borders of brooks and swamps.
The rootstocks furnish the well-known calamus or “sweet flag,
root ” sold everywhere by druggists.
7. C0MMELINACEA5. Spiderwort Family
Herbs, with slimy or mucilaginous juice; stems somewhat
succulent, jointed, leafy, simple or branched. Leaves simple,,
succulent, narrow, entire, sheathing at the base, sheaths entireSPIDERYVORT FAMILY
27
or split. Flowers in terminal cymes or umbels, bisexual, often
zygomorpkic. Sepals 3, persistent, foliaceous or colored. Petals
3, soon falling or liquefying. Stamens 6 or fewer, often some
of them abortive. Ovary 2-3-celled; style single; stigma
entire or 3-lobed. Fruit a 2-3-celled, 2-3-valved capsule; seeds
solitary or several in each cell.*
I. TRADESCANTIA L.
Perennial, stem simple or branched. Leaves very narrow.
Flowers in terminal and axillary bracted umbels, actinomor-
phic, 1 in. broad. Sepals 3, herbaceous. Petals 3, soon fall-
ing, or liquefying to jelly. Stamens 6, sometimes 3 shorter
than the others ; filaments bearded or smooth. Ovary 3-celled,
with 2 ovules in each cell; pedicels recurved in fruit. Capsule
3-celled, 3-valved, 3-6-seeded.#
1.	T. virginiana L. Spiderwort. Stem erect, stout, smooth, or
with long, soft hairs, 1-2 ft. high. Leaves linear, keeled, often
purple-veined, long, taper-pointed, 1 ft. or more in length. Bracts
similar to the leaves. Umbels sessile, 2-many-floweved, flowers in 2
rows in the bud. Petals blue or purple, twice as long as the sepals.
Stamens blue, filaments densely bearded. Capsule ovoid or oblong.
On dry, sandy soil.*
2.	T. pilosa Lehm. Hairy Spiderwort. Stem stout, erect or
zigzag, branched, with long, soft hairs, or nearly smooth, 1-2 ft.
high. Leaves linear-oblong, taper-pointed at the apex, narrowed at
the base, hairy on both sides. Umbels axillary and terminal, many-
flowered. Pedicels and sepals with soft, glandular hairs. Flowers
blue or purple, f— 1 in. wide. Seeds pitted. In rich soil.*
H. COMMELINA L.
Annual or perennial, stem branching, erect or procumbent,
smooth or downy. Leaves petioled or sessile, entire, the floral
ones heart-shaped, folded, and forming a spathe inclosing the
base of the cymes. Flowers not actinomorphic. Sepals mostly
colored, 1 of them smaller. Petals bine, unequal, 2 of them
kidney-shaped and long-clawed, the third one smaller. Stamens
6, only 3 of them fertile; filaments smooth. Capsule 1-3-celled;
seeds 1-2 in each cell.*28
KEY AND FLORA
1. C. virginica L. Virginia Dayflower. Stem erect, downy,
1-2 ft. high. Leaves lanceolate to oblong-lanceolate, taper-pointed,
3-5 in. long, somewhat rough above ; sheaths inflated, hairy, the open-
ing often fringed. Spathes containing a slimy secretion. Flowers
1 in. wide, the odd petal lanceolate. Capsule 3-seeded, the dorsal
cell not splitting open. On moist, sandy soil.*
III. ZEBRINA Schnizl.
Trailing or slightly climbing herbs. Leaves often striped.
Flowers usually in pairs. Calyx with a short tube, regularly
or irregularly 3-parted. Corolla nearly actinomorphic, with
tube longer than the calyx. Filaments naked or bearded.
Ovary 3-celled, 3-6-ovuled.
1. Z. pendula Schnizl. Wandering Jew. Stems perennial, pros-
trate or nearly so, branching freely, rooting easily at the nodes.
Leaves somewhat succulent, lance-ovate or oblong, crimson beneath,
green or dark purplish above, often with two wide silvery stripes.
Cultivated from Mexico.
8. PONTEDERIACEAE. Pickerel-Weed Family
Perennial marsh or aquatic herbs, stems simple or branched,
succulent. Leaves simple, alternate. Flowers solitary or
spiked, each subtended by a leaf-like spathe, perfect,, mostly
not actinomorphic. Perianth corolla-like, 6-parted. Stamens
3 or 6, unequal, inserted irregularly in the tube or throat of
the perianth. Ovary superior, 1- or 3-celled; style single;
stigma entire or toothed. Fruit a 1-seeded utricle.*
PONTEDERIA L.
Stem erect, from a thick, creeping rootstock, bearing a
single leaf above the middle and several sheathing, bract-like
leaves at its base. Radical leaves numerous, thick, parallel-
veined. Petiole long, from a sheathing-base. Flowers in ter-
minal spikes. Perianth 2-lipped, lobes of the upper lip ovate,
of the lower oblong, spreading. Stamens 6, the 3 upper short
and often imperfect, the 3 lower protruding. Ovary 3-celled,RUSH FAMILY
2930
KEY AND FLORA
but only 1 cell ovule-bearing; the 1-seeded utricle inclosed
by the base of the perianth.*
1. P. cordata L. Pickerel Weed. Stem stout, erect, 2-4 ft. high.
Leaves long, from heart-shaped to lanceolate and often halberd-
shaped ; apex and basal lobes obtuse, finely nerved. Spike dense,
2-4 in. long ; peduncles inclosed by the spathe. Perianth hairy, blue,
the upper lip with 2 yellow spots; tube 6-ribbed, curved,- rather longer
than the lobes. Ovary oblong. In ponds and slow streams.*
9.	JUNCACE®. Rush Family
Grass-like perennial or annual herbs, mostly growing on
wet soil. Stems mostly erect but sometimes creeping, simple
or branched, naked or leafy and jointed. Leaves cylindrical,
sheathing at the base, very slender and pointed or flattened
and grass-like. Flowers in cymes or panicles, which may be
very loose and spreading, or so compact as to form a head,
sometimes with a rigid scape prolonged beyond the flower
cluster. Flowers usually bracted. Perianth of 6 nearly equal,
scale-like, persistent divisions. Stamens 3 or 6, inserted on
the base of the perianth. Ovary free, 1- or 3-celled, many-
ovuled; style single ; stigmas 3, usually hairy. Fruit a 1- or
3-celled, 3-many-seeded capsule. [Most species flower late in
the season, and their identification is too difficult for one
without considerable experience.]*
10.	LILIACE®. Lily Family
Mostly herbs. Flowers actinomorpliic. Perianth free from
the ovary. Stamens nearly always 6, one before each division
of the perianth. Ovary usually 3-celled; fruit a pod or berry,
few-many-seeded.
Except in the genus Trillium the divisions of the perianth
are colored nearly alike.LILY FAMILY
31
SUBFAMILY I. LILIACEiE PROPER
Not tendril climbers, rarely dioecious.
A
Styles or sessile stigmas 3, more or less separate.
Leaves flat, lanceolate, or spatulate. Flowers dioecious, showy.
Chamselirium, I
Leaves grass-like. Flowers bisexual, showy. Amianthium, II
Leaves 3-ranked, strongly nerved and plaited. Flowers some-
what monoecious, small.	Yeratrum, III
B
Style undivided (in No. XXIII, 3 sessile stigmas'). Plants from root-
stocks.
Leaves perfoliate. Flowers solitary, drooping, yellow.
Uvularia, IV
Leaves broad, clasping. Flowers solitary or nearly so, drooping,
yellow.	Oakesia, V
Leaves scale-like. Thread-like branches borne in their axils.
Flowers small, bell-shaped.	Asparagus, XVIII
Leaves several-many, sessile or clasping, alternate. Flowers
small, 6-parted, white, in a terminal simple or compound
raceme.	Smilacina, XIX
Leaves only 2-3, sessile or slightly petioled. Flowers very small,
4-parted, solitary or in a small terminal cluster.
Maianthemum, XX
Leaves clasping. Flowers solitary or in pairs, greenish-white or
rose-purple, borne on pedicels abruptly bent near the middle.
Streptopus, XXI
Leaves nearly sessile or partly clasping. Flowers axillary,
greenish, on pedicels jointed near the flower.
Polygonatum, XXII
Leaves only 2, directly from the rootstock. Flowers in a raceme,
bell-shaped, white, sweet-scented.	Convallaria, XXIII
Leaves 3, netted-veined. Flower single, large, terminal.
Trillium, XXIV32
KEY AND FLORA
C
Style undivided. Plants from fibrous roots.
Flowers yellow or orange.	Hemerocallis, VIII
Flowers white.	Yucca, XVII
D
Style usually undivided. Plants from coated or solid-looking bulbs.
Leafy-stemmed plants. Flowers large, solitary, or apparently
umbeled.	Fritillaria, X
Apparently stemless plants.
(a) Plants with the smell of onions or garlic. Flowers
umbeled.	Allium, VI
("b) Plants scentless. Flowers umbeled. Nothoseordum, VII
(c) Flower solitary, erect, large.	Tulipa, XII
(d) Flower solitary, nodding.	Krythronium, XI
(e)	Flowers racemed. Perianth with hardly any tube.
Stigma a single knob.	Scilla, XIII
(/) Flowers racemed. Perianth with hardly any tube.
Stigma 3-cleft.	Camassia, XIV
(g)	Flowers eorymbed. Perianth with hardly any tube.
Leaves linear.	Ornithogalum, XV
(h)	Flowers racemed. Perianth with a tube. Leaves lance-
linear.	Hyacinthus, XVI
E
Style undivided. Plants from scaly bulbs.	Lilium, IX
SUBFAMILY II. SMILACE^l
Climbers, often tendril-bearing. Flowers dioecious.	Smilax, XXV
I. CHAM3JLIRIUM Will.!.
Rootstock short and thick, bitter. Stem simple, erect, leafy,
smooth. Lower leaves spatulate to obovate, the stem leaves
narrower. Flowers small, white, in a spike-like raceme, dioe-
cious. Perianth of 6 linear-spatulate segments. Stamens 6, fil-
aments longer than the perianth. Ovary 3-celled; styles 3.
Fruit an ovoid, 3-angled, many-seeded capsule.*LILY FAMILY
33
1. C. luteum Gray. Unicorn Root, Devil’s Brr. Stem furrowed,
staminate plants 1-2 ft. high, pistillate taller, often 3 ft. or more.
Lower leaves obovate, clustered, the upper small and bract-like. Stam-
inate racemes slender and drooping, the pistillate erect. Flowers short-
pediceled. Capsule 3-valved, seeds linear-oblong, winged at the ends-
On low ground.*
II.	AMIANTHIUM Gray. (CHROSPERMA)
Stem simple, glabrous, erect from a bulbous base. Leaves
long and slender. Flowers white, in a simple terminal raceme,
bisexual. Perianth of 6 segments which are sessile and gland-
less. Stamens 6, somewhat perigynous. Ovary 3-lobed, 3-celled;
fruit a dehiscent, 3-lobed capsule, the lobes becoming awl-
shaped by the persistent style bases ; cells few-seeded.*
1. A. muscaetoxicum Gray. Fly Poison. Bulb ovoid or oblong.
Stem somewhat angled below, 1-3 ft. high. Lower leaves strap-shaped,
channeled, the upper small and bract-like. Raceme dense, cylin-
drical, pedicels from the axils of minute ovate bracts. Perianth seg-
ments ovate, white, becoming greenish, nearly as long as the slender
stamens. Styles spreading. Capsule with divergent lobes; seeds ovoid,
red. In rich woods.*
III.	VERATRUM L.
Simple-stemmed perennials. Roots fibrous, from the thick-
ened base of the stem, poisonous, emetic. Leaves 3-ranked,
plaited, and veiny. Flowers panicled, greenish or brownish.
Sepals 6, spreading, nearly hypogynous. Stamens shorter than
the perianth, and somewhat perigynous. Ovary of 3 carpels
united at base. Fruit a few-seeded capsule, splitting into
3 parts.
1.	V. viride Ait. White Hellebore, Indian Poke. Stem stout,
2-7 ft. high, very leafy. Flowers very numerous, in a panicle, com-
posed of spike-like racemes. Sepals yellowish-green. Wet meadows
and brooksides.
2.	V. Woodii Robbins. Stem slender, 2—5 ft. high, not very leafy.
Flowers in a long, narrow panicle. Sepals greenish-purple or almost
black. Woods and dry hillsides.
IV.	UVTTLARIA L.
Rather low plants with short rootstocks. Leaves alternate,
broad, and parallel-veined. Flowers yellow or yellowish,34
KEY AND ELORA
drooping, borne singly at the end of the forking stem.
Perianth of 6 similar and separate' narrow spatulate sepals,
each grooved and nectar-bearing inside toward the base.
Stamens (3, with linear anthers, which are much longer than
the filaments. Style 3-cleft. Pod 3-lobed, 3-celled, few-seeded.
1.	U. perfoliata L. Mealy Bellwort. Leaves much as in the
preceding species. Flowers very pale yellow, with shining grains on
the inner surfaces of the twisted sepals ; anthers sharp-pointed.
Plant about two-thirds the size of the preceding.
2.	U. grandiflora Sm. Larger Bellwort. Leaves oblong, with
the base clasping the stem so as to make it appear to run through
the leaf a little way from the base. Flowers greenish-yellow, 11 in.
long; anthers obtuse. A leafy plant, 1-2 ft. high.
V. OAKESIA Wats.
Plants with much the aspect of the preceding genus, but
with merely sessile leaves, triangular winged pods, and slen-
der, creeping rootstocks.
1. 0. sessilifolia Wats. Wild Oats, Straw Lilies. Stem slen-
der, zigzag. Leaves lance-oval, thin, smooth, pale beneath, 1-11 in.
long. Flower cream color, nearly 1 in. long.
VI. ALLIUM L.
Herbs appearing stemless from coated bulbs with the
characteristic odor of onions. Bulbs solitary or clustered.
Leaves narrowly linear or slender-tubular, with a bloom.
Flowers small, on slender pedicels,’in terminal umbels on
naked scapes, the umbels often bracted or inclosed in a
spathe. Perianth 6-parted, persistent; stamens 6, somewhat
perigynous, filaments filiform or dilated below. Ovary sessile,
3-celled; style thread-like, jointed; stigma entire. Fruit a
3-celled, 3-valved, few-seeded capsule. Flowers sometimes
changed into bulblets.*
1.	A. reticulatum Don. Resembling A. Nuflallii, but with larger
bulbs. Leaves narrowly linear. Scape slender; bracts usually 2, taper-
pointed; pedicels slender, in. long. Flowers white or pink; seg-
ments of the perianth thin. Capsule crested. W.
2.	A. Nuttallii Wats. Bulbs ovoid, their coats with a fibrous net-
work. Leaves basal, narrowly linear. Scape 4-8 in. high; bractsLILY FAMILY
35
3 or 2 ; pedicels in. long. Flowers rose color or white, the seg-
ments of the perianth becoming rigid in the fruit. On prairies W.
and S.W.
3.	A. canadense L. Meadow Garlic. Bulbs ovoid, the outer
coats of white and thin, dry, netted fibers. Leaves narrowly linear,
flat, or concave above. Scape cylindrical, 1 ft. high. Bracts of the
umbel 2-3, ovate, acuminate; umbel consisting mostly of sessile bulb-
lets. The few flowers long-pediceled, rose-colored. Perianth about
as long as the stamens. Filaments dilated below. Capsule shorter
than the perianth, 6-toothed, ovules 2 in each cell. On moist soil.*
4. A. mutabile Michx. Wild Onion. Bulbs ovoid, their coats
with a very prominent fibrous network. Leaves basal, channeled,
narrowly linear. Scape 1-2 ft. high, bracts taper-pointed, pedicels
almost 1 in. long. Umbel rarely bearing bulblets. Flowers pink,
rose color, or white; segments of the perianth thin. In moist soil
S. and W.
5.	A. vineale L. Field Garlic. Bulb mostly solitary. Leaves
cylindrical, hollow, very slender. Scape slender, sheathed below the
middle by the bases of the leaves. Umbels often crowded with
bulblets. A troublesome weed in moist meadows and fields eastward,
giving milk a strong flavor of onions or garlic. Naturalized from
Europe.
VII. NOTHOSCORDUM Kuntli
Scape-bearing herbs resembling Allium, but with no odor of
onions. Flowers yellow or yellowish-green, in a loose, erect
umbel, with 2 bracts.
1. N. bivalve Britton. Bulb small, often with little bulbs at its
base. Leaves narrowly linear. Scape not exceeding 1 ft. high, the
umbel 2-bracted, pedicels thread-like, at length 1-2 in. long. Flowers
| in. long or less, the perianth segments narrowly oblong, thin. On
prairies and in open woods.
Vm. HEMEROCALLIS L.
Perennial, from a fascicle of fleshy roots. Stem erect,
branched, smooth. Leaves mostly basal and linear. Flowers
on branching scapes, large, yellow or orange, solitary or
corymbed. Perianth funnelform, with a spreading limb much
longer than the tube. Stamens 6, inserted in the top of the
tube, shorter than the lobes, curved upward. Ovary 3-celled,
many-ovuled ; style longer than the stamens, curved upward;
stigma knobbed. Fruit a 3-celled, 3-angled capsule.*36
KEY AND FLORA
1. H. fulva L. Day Lily. Scapes stout, branched above, with a
few bract-like leaves, smooth, 3-5 ft. high. Leaves very long, strap-
shaped, acute, channeled. Flowers short-pediceled, tawny-yellow;
perianth lobes oblong, netted-veined, lasting only one day. Intro-
duced from Asia and common in old gardens.*
IX. LILIUM L.
Perennial, from scaly bulbs; stem erect, leafy, usually tall
and slender. Leaves sessile, scattered or whorled. Flowers
large, erect or drooping. Perianth corolla-like, deciduous;
segments 6, spreading or recurved above, sessile or clawed,
each with a nectar-bearing groove near the base. Stamens 6,
elongated; anthers linear, versatile. Ovary 3-celled, many-
ovuled; style long and slender; stigma 3-lobed. Fruit a 3-
celled, dehiscent, many-seeded capsule.
1.	L. longiflorum Thunb. Long-Flowered WniTE Lily. Stem
1-	3 ft. high. Leaves thick, lanceolate, scattered. Flower single,
pure white, funnel-shaped, 5-6 in. long. Var. eximium, the Easter
lily, bears several very showy and sweet-scented flowers. Cultivated
from China and Japan.
2.	L. philadelphicum L. Wild Red Lily. Stem 2-3 ft. high.
Leaves linear-lanceolate, the upper ones generally whorled. Flower
usually solitary (sometimes 2 or 3), erect, reddish-orange, with
tawny or purplish spots inside. Sepals with claws. Dry or sandy
ground, borders of thickets, etc.
Var. andinum Ker. Western Red Lily. Stem rather slender.
Leaves linear, all alternate or the upper ones whorled. Flowers 1-3,
erect. Segments of the perianth red, orange, or yellow, spotted
beneath, the claw shorter than the blade. In dry soil W.
3.	L. canadense L. Wild Yellow Lily, Meadow Lily. Stem
2-	5 ft. high. Leaves lanceolate, 3-nerved, the margins and nerves
roughish with short hairs, whorled. Flowers usually 3, sometimes
more numerous, all nodding, on peduncles 3-6 in. long, yellow or
orange, with dark purple or brown spots inside. Sepals without
claws, recurved. Moist meadows and borders of woods.
X. FRITILLARIA L.
Leafy-stemmed perennials, from scaly or coated bulbs.
Flowers single or several, nodding. Perianth bell-shaped, a
nectar-bearing spot above the base of each division. Stamens
as long as the petals.LILY FAMILY
37
1.	F. Meleagris L. Guinea-IIen Flower. Stem 1 ft. high. Leaves
linear, alternate, channeled. Flower usually single, large, purplish,
checkered with blue and purple or yellow. Cultivated from Europe.
2.	F. imperialis L. Crown Imperial. Stein 3-4 ft. high. Leaves
abundant in whorls about the middle or lower part of the stem, lan-
ceolate or lance-oblong. Flowers several, large, yellow or red, in an
umbel-like cluster beneath the terminal crown of leaves. Cultivated
from Europe.
XI.	ERYTHRONIUM L.
Nearly stemless herbs, arising from rather deeply buried
bulbs. Leaves 2, long and smooth, with underground petioles.
Scape arising from between the bases of the leaves. Flower
commonly single, nodding.
1.	E. americanum Ker. Yellow Adder’s-Toxglte. Leaves mot-
tled. Flowers handsome. Perianth light yellow'. Style club-shaped;
stigmas united.
2.	E. albidum Nutt. White Dogtooth Violet. Leaves not much
mottled. Perianth bluish-white. Stigmas 3. short and spreading.
XII.	TULIP A L.
Herbs appearing stemless, from coated bulbs. Leaves sessile.
Scape simple. Flower solitary, erect. Perianth bell-shaped.
Stamens short, awl-shaped, with broadly linear anthers. Style
short; stigma thick, 3-lobed; ovary and pod triangular.
1. T. Gesneriana L. Common Tulip. Leaves 3-6, ovate-lanceo-
late, close to the ground. Flower large, on a smooth peduncle, color
red, yellow, white, or variegated. Cultivated from Asia Minor. Many
garden varieties exist.
XIII.	SCILLA L.
Perennial herbs, appearing stemless, from coated bulbs.
Leaves linear. Flowers racemed on a scape, generally blue.
Divisions of the perianth 1-nerved, parted almost to the base.
Filaments 6, often broad at the base. Style slender, with a
knob-like stigma. Ovary 3-angled, 3-celled.
1. S. sibirica Andr. Siberian Squill. Scapes 3-8 in. high, sev-
eral from each bulb, 2-3-flowered. Leaves 2-4, narrowly strap-shaped.
Flowers intense blue, short-peduneled, often nodding. Cultivated from
Russia and Siberia.38
KEY AND FLORA
XIV.	CAMASSIA Lindl. (QUAMASIA)
Herbs appearing stemless, from coated bulbs. Leaves linear.
Flowers racemed on a scape. Perianth of 6 blue or purple
spreading sepals. Stamens with thread-like filaments, slightly
perigynous. Style thread-like, ending in a knobbed stigma.
Capsule 3-angled, 3-celled, several-seeded.
1. C. esculenta Robinson. Wild Hyacinth. Leaves keeled, weak,
shorter than the scape. Flowers in a long-bracted raceme, pale blue.
River bottoms and other damp, rich soil.
XV.	ORNITHOGALUM L.
Herbs appearing stemless, from coated bulbs. Leaves linear,
fleshy. Scape erect. Flowers in corymbs or racemes, bracted.
Perianth segments 6, white, nerved, persistent. Stamens 6,
hypogynous, slender; filaments flattened. Ovary sessile, 3-
celled, few-ovuled. Fruit a roundish, 3-angled capsule, seeds
black,*
1. 0. umbellatum L. Star of Betiilf.hem. Bulb ovoid, mem-
brauous-coated. Leaves numerous, linear, fleshy; mid-vein nearly
white, as long as the scape. Scape slender, 6-12 in. high. Flowers
o'pening in sunshine, long-pediceled. Bracts linear-lanceolate, about
as long as the pedicels. Perianth segments oblong-lanceolate, white
with a green stripe on the back, twice the length of the stamens.
Introduced from Europe; very common about old gardens.*
XVI.	HYACINTHUS L.
Herbs appearing stemless, from coated bulbs. Leaves linear,
fleshy. Flowers in an erect spike, pediceled, bracted. Perianth
tubular below, lobed and spreading above. Stamens short, in-
cluded. Style short; stigma knobbed; ovary 3-celled, mauy-
ovuled.*
1. H. orientalis L. Hyacinth. Leaves lance-linear, thick and
fleshy, smooth. Scape erect, many-flowered. Segments united about
half their length, white, blue, or red. Filaments very short. Ovary
rarely maturing seed. Common in cultivation.*
XVII.	YUCCA L.
Plants with woody and leafy stems. Leaves numerous, rigid,
spine-pointed, persistent. Flowers in large terminal racemesLILY FAMILY
39
or panicles, bracted, nodding. Perianth bell-shaped; segments
6, nearly alike, deciduous. Stamens 6 ; filaments thickened
above, often papillose; anthers small. Ovary sessile, 3-celled
or becoming 6-celled, 3-angled, many-ovuled. Fruit an ob-
long, 3-angled, many-seeded, dehiscent capsule, or fleshy and
indehiscent.*
1.	Y. glauca Nutt. Bear Grass. Soap Weed. Stem very short.
Leaves basal, long, straight and slender, stiff, sharp-pointed, the
margins white and with a few thread-like filaments, J-I in. wide.
Flowers racemed, greenish-white, globose or oblong, bell-shaped.
Style green ; capsule large, oblong, six-sided. Dry soil W.
2.	Y. filamentosa L. Spanish Dagger. Stem stout, 4-12 in. high.
Leaves linear or linear-lanceolate, slender-pointed, narrowed above
the spreading and clasping base, spreading or recurved, smooth, with
loose, thread-like filaments on the margins. Panicle elongated, with
bract-like leaves on the scape, widely branched, downy-hairy above,
3-0 ft. high. Perianth white, bell-shaped, 2 in. wide. Capsule oblong,
angles rounded, sides furrowed, at length 3-valved and dehiscent. In
sandy soil, and often cultivated for ornament.*
XVm. ASPARAGUS L.
Stem from fleslry, fibrous roots, erect, branched; branches
slender, with thread-like branclilets in the axils of scales ivhich
take the place of leaves. Flowers small, solitary or racemed.
Perianth 6’-parted; segments distinct or slightly united. Sta-
mens 6, perigynous; filaments thread-like. Ovary 3-celled, 6-
ovnled ; style short, slender; stigmas 3, recurved. Fruit a
berry.*
1. A. officinalis L. Asparagus. Stem succulent and simple, with
fleshy scales when young; becoming taller, more woodjg and widely
branched, when old. Flowers axillary, solitary, or 2 or 3 together on
slender, jointed, drooping pedicels, greenish ; segments linear. Berry
red, few-seeded. Introduced from Europe, common in cultivation,
and often escaped.*
XIX. SMILACINA Desf. (VAGNERA,
Perennial, simple-stemmed herbs, with rootstocks. Leaves
usually sessile, nerved, alternate. Flowers white, in a terminal
raceme. Perianth spreading, 6-parted. Stamens 6, somewhat
perigynous; filaments slender; anthers short, facing inward.40
KEY AND FLORA
Ovary 3-celled, 6-ovuled; style short and stout, with a some-
what 3-lobed stigma. Fruit a 1-2-seeded berry.
1.	S. racemosa Desf. False Spikenard. A showy plant with
curved stem 1-3 ft. high, downy throughout. Leaves abundant, oval
or ovate-lanceolate, taper-pointed. Flowers small, in a compound
raceme. Berries pale red, speckled with dark red or purple. Moist
thickets.
2.	S. stellata Desf. Plant 1 ft. or less in height, nearly smooth.
Leaves broadly lanceolate, acute, clasping. Flowers few, larger than
in No. 1, in a simple raceme. Berries very dark red. Along river
banks.
XX.	MAIANTHEMUM Wiggers. (UNIFOLIUM)
Stem low. Leaves 2-3, lanceolate or ovate, with a heart-
shaped base. Flowers small, white, solitary or in a sim-
ple raceme. Perianth 4-parted. Stamens 4. Ovary 2-celled;
stigma 2-lobed.
1. M. canadense Desf. Two-Leaved Solomon’s Seal, Wild
Ltly of the Valley. Plant 3-6 in. high. Leaves very short-
petioled. Fruit a globular or ovoid berry, whitish, with brownish-
red blotches. Woods and shaded banks N.
XXI.	STREPTOPUS Miehx.
Herbs with forking stems from a creeping rootstock. Leaves
clasping. Flowers small, borne singly or in pairs on peduncles
which arise above the leaf axils and which are sharply bent
or twisted near the middle. Anthers arrow-shaped. Ovary
3-celled, ripening into a red, many-seeded berry.
1.	S. amplexifolius DC. Liver Berry. Stem smooth, 2 ft. or
more high. Leaves smooth-margined. Flowers greenish-white. Damp
woods.
2.	S. roseus Miehx. Liver Berry, Jacob’s Ladder. Branches
with a few bristly hairs. Lower leaves margined with fine bristles.
Flowers reddish or purplish. Cold, damp woods N.
XXII.	POLYGONATUM Hill. (SALOMONIA)
Rootstock creeping, jointed, scarred. Stems simple, erect,
scaly below, leafy above. Leaves alternate, oval or oblong.
Flowers on axillary, 1-4-flowered, drooping, jointed peduncles.LILY FAMILY
41
Perianth tubular, 6-cleft. Stamens 6, included, inserted about
the middle of the tube; anthers arrow-shaped. Ovary 3-
celled, many-ovuled; style slender; stigmas knobbed or 3-
lobed. Fruit a few-seeded berry.*
1.	P. biflorum. Ell. Hairy Solomon’s Seal. Stem simple, erect,
arched, nearly naked below, 1-2 ft. high. Leaves 2-ranked, sessile
or clasping, 3-7-nerved, smooth above, pale and downy beneath.
Peduncles short, 1-4, often 2-flowered. Perianth greenish, 1-2 in.
long. Filaments thread-shaped, roughened. Berry dark blue. Shady
banks.*
2.	P. commutatum Dietrich. Smooth Solomon’s Seal. Stem
simple, stout, curving above, 3-8 ft. high. Leaves lanceolate to ovate,
many-nerved, partly clasping, smooth on both sides. Peduncles
nearly half as long as the leaves, 2-6-flowered. Perianth greenish-
yellow, J in. long. Filaments smooth. Berry blue, 1- in. in diameter.
In rocky woods and along streams.*
XXIII. CONVALLARIA L.
Low, smooth, apparently stemless, perennial herbs. Leaves 2,
oblong, with long petioles, from a slender, creeping rootstock.
Scape slender, angled, inclosed at the base by the leafstalks.
Flowers racemed, white, drooping. Perianth bell-sliaped, with
recurved lobes. Stamens borne on the base of the perianth.
Ovary 3-celled, ripening into a few-seeded red berry.
1. C. majalis L. Lily of the Valley. A familiar garden flower,
cultivated from Europe, and also found wild in mountain woods from
Virginia to Georgia.
XXIV. TRILLIUM L.
Low herbs, with the stem springing from a short rootstock.
Leaves 3, large, netted-veined, in a whorl. Flower large, ter-
minal. Perianth of 6 parts, the 3 sepals unlike the 3 petals
in color and in texture. Stamens 6, with the linear anthers
usually opening inward, longer than the filaments. Stigmas
3, sessile, spreading at the tips ; ovary 3- or 6-angled, 3-celled,
many-seeded. Fruit a roundish, many-seeded purple berry.
1. T. sessile L. Rootstock erect or ascending, corm-like. Stem
slender, 1-8 in. high. Leaves broadly oval, obtuse or acute at the
apex, rounded and sessile at the base, 3-5-nerved, smooth, bright42
KEY AND FLORA
green, not mottled. Flowers sessile; sepals lanceolate, J-l in. long;
petals purple, elliptical, about the length of the sepals. Stamens half
the length of the petals. Styles elongated, straight. In rich woods.*
2.	T. erectum L. Squawroot, Benjamin. Rootstock rather up-
right, large and stout. Leaves broadly diamond-shaped, tapering to
a short point. Pedicel 1-3 in. long, not quite erect. Petals ovate to
lanceolate, much broader than the sepals, of a rich brownish-purple
or sometimes white or pale. Stigmas distinct, stout, and spreading.
The disagreeable scent of the flower has given rise to several absurd
popular names for it. In rich woods.
3.	T.grandiflorum Salisb. Large-Flowered Wake-Robin. Root-
stock horizontal, stem slender, 12-18 in. high. Leaves rhombic-
ovate, taper-pointed at the apex, rounded and sessile or slightly
peduncled at the base, smooth and with a bloom, 5-7-nerved, bright
green. Peduncle longer than the erect or slightly declined flower.
Sepals lanceolate-acute, 1-1J in. long. Petals white, fading to pink,
longer than the sepals. Stamens less than half the length of the
petals. Style short; stigmas recurved. Fruit a black, roundish berry.
In rich woods.*
4.	T. cernuum L. Nodding Trillium. Stem 8-20 in. high.
Leaves broadly rhombic or rhombic-ovate, 2-4 in. wide, taper-
pointed, sessile or nearly so. Peduncle recurved beneath the leaves.
Petals white or pink, wavy, somewhat recurved, as long as the
sepals or a little longer. Stamens with filaments about equaling the
anthers. Stigmas stout, recurved. Rich moist woods.
5.	T. nivale Riddell. Dwarf White Trillium. Stem 2-4 in.
high. Leaves petioled, oval to ovate. Flower white, erect. Petals
J-1J in. long, ovate-spatulate. Rich, damp woods, blooming with
the very earliest spring floivers.
6.	T. undulatum Willd. Painted Trillium. Stem 8-12 in. high.
Rootstock oblique to the rest of the stem, rather small; roots long
and fibrous. Leaves ovate, taper-pointed. Petals white, penciled at
the base, with purple stripes, lance-ovate, somewhat recurved, wavy.
Cold woods, especially N.
XXV. SMILAX L.
Mostly woody vines, usually with prickly stems, climbing
by tendrils. Rootstock often large and tuberous. Leaves alter-
nate, prominently nerved, netted-veined, petioled; stipules re-
placed by persistent tendrils. Flowers regular, dioecious, small,
greenish, in axillal-y umbels. Perianth bell-shaped, segments
0. Stamens 6, distinct. Ovary 3-celled, 3-6-ovuled; stigmas
1-3, sessile or nearly so. Fruit a 1-6-seeded globose berry.AMARYLLIS FAMILY
43
1.	S. herbacea L. Carrion Flower. Stem herbaceous, erect,
simple or branched, not prickly, 1-3 ft. high. Leaves few, ovate,
acute, and mucronate at the apex, somewhat heart-shaped at the
base, 5-7-nerved, thin, smooth above, downy below, the upper some-
times whorled and the lower bract-like; petiole short. Peduncles as
long as the leaves, growing from below the petiole. Umbel many-
flowered, flowers carrion-scented. Berry blue-black, 2-4-seeded. Dry,
fertile soil.*
2.	S. Walteri Pursh. Green-Brier. Stem low, with few prickles,
2-	5 ft. long; branches slightly 4-angled, unarmed. Leaves oblong-
lanceolate to oval, obtuse or acute at the apex, rounded or cordate
at the base, 5-ribbed, smooth. Peduncles flattened, about as long as
the petioles and pedicels. Berry bright red, ripening the first year.
Wet pine barrens.*
3.	S. rotundifolia L. Green-Brier, Cat-Biiier, Dog-Brier,
Horse-Brier, Wait-a-Bit. Stem green, strong; branchlets, and
sometimes the branches, 4-angled, armed with stout hooked prickles.
Leaves ovate or round-ovate, with a slightly heart-shaped base and
an abruptly pointed tip. Berries black, with a bloom. Thickets, the
commonest species N. E.
4.	S. glauca Walt. Green-Brier. Stem cylindrical, slender,
with scattered prickles, branches angled and usually without prickles.
Leaves ovate or subcordate, pointed at the apex, mostly 5-nerved,
smooth, white beneath, with a bloom, margin entire. Peduncle flat-
tened, 2-3 times as long as the petiole, few-flowered. Berry black,
3-	seeded. Margin of swamps.*
5.	S. Bona-nox L. Bamboo Vine. Stem stout, cylindrical or
slightly angled, scurfy when young, armed with numerous stout
prickles. Branches 4-angled, usually unarmed. Leaves triangular,
ovate, or often halberd-shaped, 5-7-ribbed, smooth on both sides
and often discolored; margins usually fringed with fine prickles.
Peduncles twice as long as the petioles, flattened. Umbels many-
flowered; pedicels short. Berries 8-20 in a cluster, black, 1-seeded.
In swamps and thickets.*
11. AMARYLLIDACEAi. Amaryllis Family
Mostly smooth perennial herbs, from bulbs. Leaves basal,
with no distinction between petiole and blade. Flowers borne
on a scape, nearly or quite actinomorphic. Stamens 6. Style 1.
Limb of the 6-parted, corolla-like perianth epigynous. Ovary
3-celled. Capsule 3-celled, several-many-seeded.44
KEY AND FLORA -
I.	NARCISSUS L.
Scapes with 1-several flowers from a thin, dry spathe.
Flowers with a cup-shaped or other crown on the throat of
the perianth; tube of the perianth somewhat cylindrical, the
6 divisions of the limb widely spreading. Stamens 6, inserted
in the tube.
1.	N. Psuedo-Narcissus L. Daffodil, Daffy, Easter Flower.
Scape short, bearing 1 large yellow flower; tube of perianth short
and wide, crown with a crimped margin. Cultivated from Europe.
2.	N. Tazetta L., var. orientalis. Chinese Sacred Lily. Bulb
large, often with many smaller ones attached to its base. Scape 1 ft.
or more high. Flowers several, umbeled, fragrant. Perianth w'hite
or nearly so, the crown rather spreading, finely scalloped, yellow or
orange. Cultivated from China.
3.	N. poeticus L. Poet’s Narcissus. Scape 1-flowered. Perianth
pure white, the crown very narrow, edged with pink. Cultivated from
S. Europe.
II.	ZEPHYRANTHES Herb. (ATAMOSCO)
Stemless, from a coated bulb. Leaves linear, fleshy. Scape
erect, 1-few-flowered. Flowers large, erect, or declined, sub-
tended by a 1-2-leaved spathe. Perianth 6-parted, naked in
the throat; tube short, segments petal-like, spreading. Stamens
free, anthers versatile. Ovary 3-celled, many-ovuled; style
elongated, declined; stigma 3-cleft. Fruit a many-seeded, 3-
valved capsule; seeds black, compressed, or angled.*
1. Z. Atamasco Herb. Atamasco Lily. Bulbs about 1 in. in
diameter. Leaves narrow, concave above, smooth, usually longer
than the scape. Scape 6-12 in. high, 1-flowered. Spathe 1-leaved,
2-cleft. Flowers 2-3 in. long, white, tinged with pink or purple,
bell-shaped, short-peduneled. Stamens longer than the tube, shorter
than the style. Capsule depressed-globose, seeds angled. In rich,
damp soil, often cultivated.*
III.	HYPOXIS L.
Small, apparently stemless herbs. Leaves grass-like, hairy,
from a solid bulb. Scapes thread-like, few-flowered. Perianth
6-parted, wheel-shaped, the 3 outer divisions greenish on the
outside, the whole perianth withering on the pod. Seeds
numerous.IRIS FAMILY
45
1. H. hirsuta Coville. Star Grass. Leaves longer than the scape,
both sparsely set with long, soft hairs. Scape 3-8 in. high. Flowers
1-	4, about in. across, yellow. Common in meadows and dry woods.
12. IRIDACE2E. Iris Family
Perennial herbs from bulbs, corms, or rootstocks. Leaves
2-	ranked, equitant. Flowers bisexual, often actinomorphic,
each subtended by two bracts. Periantli 6-parted, the seg-
ments epigynous in 2 series of 3 each, equal, or the inner
ones smaller. Stamens 3, distinct or united,'opposite the
outer segments. Ovary forming a 3-celled, 3-angled, 3-valved,
many-seeded, dehiscent capsule.*
I. CROCUS L.
Leaves springing from the corm. Flowers sessile on the
conn. Tube of the perianth very long and slender, its divi-
sions all alike or nearly so. Stigmas 3-cleft.
1. C. vernus All. Spring Crocus. Leaves linear. Stigmas short.
Flowers white, blue, or purple. Our earliest garden flower. Culti-
vated from Europe.
n. IRIS L.
Rootstock thick, creeping, branching, horizontal, sometimes
tuberous. Stems erect, simple or branched. Leaves linear or
sword-shaped. Flowers showy, the outer perianth segments
spreading or recurved, often bearded within, the inner seg-
ments usually smaller and erect. Stamens inserted in the base
of the outer segments. Style deeply 3-parted (Fig. 8), the
divisions broad and petal-like, covering the stamens. Fruit an
oblong or oval, 3- or 6-angled, many-seeded capsule (Fig. 9).*
1. I. versicolor L. Large Blue Flag. Rootstock thick, horizon-
tal. Stem cylindrical, smooth, simple or branched, leafy, 2-3 ft. high.
Leaves linear, sword-shaped, finely nerved, with a bloom, the lower
1J-2 ft. long, the upper shorter. Bracts longer than the pedicels.
Flowers terminal, single or few together, blue variegated with white,
yellow, and purple; perianth segments not bearded, the inner ones
smaller. Ovary 3-angled, longer than the inflated perianth tube. Cap-
sule oblong, slightly lobed ; seeds 2 rows in each cell. In wet places.*46
KEY AND FLORA
Fig. 8. Iris
I, flower. II, seed, longitudinal section. Ill, flower with outer segments of
perianth removed: stig., stigma, ov., ovary
I, flower, longitudinal section: ov., ovary. II, diagram showing stigmas
opposite the stamens; III, capsule, splitting between the partitionsORCHIS FAMILY
47
2.	I. prismatica Pursh. Slender Blue Flag. Rootstock rather
slender, with tuber-like thickened portions. Stem slender, cylin-
drical, usually unbranched, 1-3 ft. high. Leaves 2-3 in number, nar-
rowly linear, in. wide. Flowers slender-peduncled, solitary or in
twos, blue with yellow veins, the perianth tube beardless and crest-
less. Ovary 3-angled; capsule sharply 3-angled. Marshy soil near
the coast.
3.	I. fulva Ker. Yellow Flag. Rootstock fleshy. Stem simple
or branched, grooved, 1-angled below, bearing 2^3 leaves, 2-3 ft.
high. Leaves linear, sword-shaped, with a bloom, shorter than the
stem; bracts small. Pedicels short, flowers axillary and terminal,
dull yellow or reddish-brown, variegated with blue and green, peri-
anth segments not bearded. Style branches but little exceeding the
stamens; ovary about as long as the inflated perianth tube; capsule
ovate, 6-angled. Swamps and wet places.*
4.	I. germanica L. Flicur-de-Lis. Rootstock thick, matted. Stem
stout, branched, leafy, 2-3 ft. high. Leaves strap-shaped, acute, erect,
shorter than the stem; bracts scarious. Flowers sessile, large and
showy, blue variegated with white and yellow, sometimes nearly all
white; outer segments large, recurved, bearded, the inner narrower,
erect, or arched inward. Introduced from Europe; common in gar-
dens and naturalized in many places.*
HI. SISYRHINCHIUM L.
Small, grass-like perennials. Stems erect, flattened, or
winged. Roots fibrous. Leaves linear or lanceolate. Flowers
small, blue, quickly withering, in terminal 2-bracted umbels.
Perianth corolla-like, of 6 bristle-pointed segments; tube
nearly or wholly lacking. Stamens 3, completely monadel-
phous. Stigmas 3, thread-like. Fruit a nearly globular,
3-angled capsule. Species too difficult for the beginner; all
commonly known as Blue-Eyed Grass.
13. 0RCHIDACE2E. Orchis Family
Perennial herbs with simple stems, often arising from bulbs
or tubers. Leaves simple, usually alternate and entire. Flow-
ers bisexual, generally showy, epigynous, zygomorphic, and
often of extraordinary shapes. Perianth of 6 divisions. Sta-
mens l or 2, united with the pistil; pollen of comparatively48
KEY AND FLORA
few grains, held together in masses by cobweb-like threads.
Ovary 1-celled, containing many (sometimes more than a mil-
lion) very minute ovules.
The family is a difficult one, and most of the genera are so
rare that specimens should not be collected in large numbers
for class study. Two of the most familiar genera are Cypri-
pedium, or Lady’s Slipper, and Spiranthes, or Lady’s Tresses.
Many of the genera are tropical air plants.
SUBCLASS II. DICOTYLEDONOUS PLANTS
Stems composed of bark, wood, and pith ; the fibro-vascular
bundles in rings; in woody stems which live over from year
to year, the wood generally in annual rings, traversed at right
angles by medullary rays. Leaves netted-veined. Parts of the
flower usually in fours or fives. Cotyledons 2 (rarely none).
14. SALICACEAJ. AA’illow Family
Dioecious trees or shrubs, with flowers in catkins, destitute
of floral envelopes. Fruit a 1-celled pod, with numerous seeds,
provided with rather long and silky down, by means of which
they are transported by the wind.
I. SALIX L.
Shrubs or trees, branches usually very slender. Buds with
single scales. Leaves usually long and narrow; stipules some-
times leaf-like or often small and soon deciduous. Bracts of
the catkins entire. Staminate catkins erect or drooping
(Fig. 10); staminate flowers with 2-10, mostly 2, distinct or
united stamens. Pistillate catkins usually erect (Fig. 10);
flowers with a small gland on the inner side of the bract;
stigmas short, 2-lobed. Capsule 2-valved.#
[Thirty or more species of willow are found growing wild in the
northeastern and north central states, but they are very hard, even
for botanists, to identify.]WILLOW FAMILY
49
1.	S. nigra Marsh. Black Willow. A small tree with very
brittle branches. Leaves elliptical or narrowly lanceolate, acute at
each end, serrate, short-petioled, downy when young and becoming
smooth with age, 2-3 in. long; stipules persistent or deciduous.
Starninate catkins 1-2 in. long; the pistillate 2-4 in. long. Stamens
3-7, distinct; filaments soft-hairy below. Capsule twice the length
of the pedicel, ovate, taper-pointed, pointed by the prominent style.
Along streams and borders of marshes.*
2.	S. lucida Muhl. Shining “Willow. A large shrub or some-
times a bushy tree 20 ft. high, with smooth bark, yellowish-brown
and shining on the twigs. Leaves varying from ovate to lanceolate,
usually with very slender
tapering points, sharply
and finely serrate, firm,
green, and glossy on both
sides, 3-5 in. long; stip-
ules small, oblong, usually
persistent. Catkins borne
on short leafy branches,
the starninate ones stout,
1-1 i in. long, the pistil-
late ones slender, l£-2
in. long, lengthening in
fruit to 3-4 in. Stamens
usually 5. Capsule nar-
rowly ovoid or cylindrical,
pointed,smooth, and shin-
ing. Banks of streams,
lakes, and swamps. One
of the most beautiful wil-
lows from the showiness
of the starninate catkins
and the large glossy leaves.
3.	S. alba L. White
Willow, Yellow Wil-
low'. A spreading tree
50-80 ft, high, with rough
gray bark, yellowish-green on the twigs. Leaves lanceolate, narrowed
at the base, with long tapering points, gray or silky-downy on both
sides when young, the upper surface (especially in Yar. vitellina)
becoming smooth when old, 2-4 in. long; stipules ovate-lanceolate,
deciduous. Catkins on short leafy branches, the pistillate ones slen-
der, cylindrical, 1|-3| in. long. Stamens usually 2. Capsule ovoid,
pointed. Cultivated from Europe (especially Var. vitellina), and
Fig. 10. White willow (Salix alba)
A, starninate catkin, natural size; B, pistillate
catkin, natural size; f', a starninate flower,
magnified; D, a pistillate flower, magni-
fied. (After Cosson and De Saint-Pierre)50
KEY AND FLORA
occasionally escaped from cultivation along streams. Very variable
and with many hybrids.
4.	S. babylonica L. Weeping Willow. A spreading tree, some-
times (10 ft. or more in height, with drooping branches. Leaves nar-
rowly lanceolate, taper-pointed, serrate, slightly downy when young
and becoming smooth with age, green above, pale beneath, often 5-7
in. long; petioles short, glandular. Catkins on short lateral branches.
Stamens 2. Style almost none. Capsule sessile, smooth. Introduced
and cultivated for ornament.
5.	S. cordata Muhl. Heart-Leaved Willow. A shrub 4-10 ft.
high, with twigs finely downy or smooth. Leaves oblong-lanceolate,
taper-pointed, finely and sharply serrate, often tapering but frequently
obtuse or somewhat heart-shaped at the base, finely downy when
young (especially on the midrib) but smooth when old; sometimes
5 in. long; stipules usually large and conspicuous, unequal-sided,
finely serrate, generally persistent. Catkins with bracts at the base,
opening earlier than the leaves, the staminate ones very silky, less
than 1 in. long, the fertile ones in fruit 14-2J in. long. Capsules nar-
rowly ovoid, pointed. In wet soil and along streams, very variable
and widely distributed.
6.	S. discolor Muhl. Glaucous Willow, Pussy Willow'. A
low .tree, sometimes 20 ft. or more in height, w'ith light greenish-
brown or reddish-brown bark. Leaves oblong-lanceolate, tapering at
both ends, finely and irregularly toothed or nearly entire, on slender
petioles, smooth and firm, bright green above, smooth or silvery
white below, 3-5 in. long; stipules often leaf-like, unsymmetrical,
usually deciduous. Staminate catkins very white and silky, oblong-
cylindrical, 1 in. or more long, appearing much earlier than the
leaves; pistillate catkins lj-2£ in. or more long. Stamens 2, W'ith
long, slender filaments. Capsule cylindrical or nearly so, long-beaked.
Common in wet meadows or along streams and swamps.
II. POPULUS L.
Trees with prominent scaly buds, twigs more or less angled.
Leaves usually long-petioled.
Flowers borne in long, drooping catkins, which appear
before the leaves ; scales of the catkins irregularly cut toward
the tip. Stamens 8-30 or more. Stigmas 2-4. Capsules open-
ing early by 2-4 valves.
1. P. alba L. Silver-Leaved Poplar, White Poplar. A large
tree, sometimes more than 100 ft. high, with smooth greenish-gray
bark. Leaves broadly ovate, rhombic-oval or nearly orbicular, lobedBAYBERRY FAMILY
51
or very coarsely toothed, densely white-downy beneath. Cultivated
as a shade tree and sometimes found growing spontaneously.
2.	P. tremuloides Michx. American Aspen, Quaking Asp. A
tree 20-60 ft. high, with greenish-white bark. Leaves roundish,
heart-shaped, abruptly pointed, with small regular teeth. Leafstalk
long, slender, and flattened at right angles to the broad surfaces of
the leaf, causing- it to sway edgewise with the least perceptible
breeze. Common especially X.
3.	P. grandidentata Miehx. Large-Toothed Poplar. A tree
60-80 ft. high, with rather smooth gray bark. Leaves 3-5 in. long,
roundish-ovate and irregularly sinuate-toothed; when young com-
pletely covered wTith white silky wool, which is shed as soon as the
leaf matures. The petiole is somewhat flattened, but not nearly as
much so as that of the preceding species. Rich woods X.
4.	P. heterophylla L. Swamp Poplar. Branches only slightly
angled. Leaves ovate, mostly obtuse at the apex, rounded or sub-
cordate at the base, serrate with obtuse teeth, densely woolly when
young, but becoming smooth with age; petioles cylindrical. Pistil-
late catkins smooth, erect or spreading, loosely flowered. Capsule
ovoid, usually shorter than the pedicel. Common in river swamps.
A large tree with soft light wood, which is often used in making
cheap furniture.*
5.	P. deltoides Marsh. Cottonwood. A large and very rapidly
growing tree, 75-100 ft. or more high, often with a markedly excur-
rent trunk. Leaves large and broadly triangular, with crenate-serrate
margins and long, tapering, acute tips; petioles long and considera-
bly flattened. The numerous pediceled capsules are quite conspicu-
ous when mature, and the air is filled with the downy seeds at the
time when the capsules open. Common W., especially along streams,
and planted as a shade tree.
15. MYRICACEiE. Bayberry Family
Shrubs with alternate, simple, resinous-dotted leaves ; monoe-
cious or dioecious. Flowers in short, bracted catkins ; perianth
none. Staminate flowers 2-10, stamens hypogynous ; pistillate
flowers surrounded by 2-6 scales. Ovary 1-celled; style short;
stigmas 2.
I. MYRICA L.
Shrubs or small trees with the branches clustered at the
end of the growth of the previous season. Leaves short-
petioled, entire, lobed or toothed, the margin usually revolute,52
KEY AND FLORA
without stipules. Perianth none. Staminate flowers in oblong,
or cylindrical catkins ; stamens 2-10, with the filaments united
below. Pistillate flowers surrounded by a cup of 2-6 scales;
ovary solitary, becoming a 1-celled, roundish drupe or nut, often
covered with waxy grains. Whole plant usually fragrant.*
1.	M. carolinensis Mill. Waxberry, Bavbeery. A spreading
shrub or small tree ; young branches downy. Leaves lanceolate or
oblong-lanceolate, entire or sometimes serrate near the mostly obtuse
apex, smooth or downy on the veins beneath, tapering into a short
petiole. Flowers mostly dioecious. Staminate catkins numerous,
stamens 4. Pistillate catkins small, bracts slightly 3-lobed, scales of
the ovary 4, fringed with hairs; stigmas ‘2. Fruit very abundant,
incrusted with white wrax, j-i in. in diameter, sometimes persistent
for 2 or 3 years. Common on wet soils, especially near the coast.*
2.	M. asplenifolia L. Sweet Fern. A shrub 2 ft. or less in
height, with brown twigs. Leaves fern-like, linear-lanceolate, 20-30-
lobed, 3-5 in. long and very fragrant. Often monoecious. Staminate
catkins cylindrical; pistillate catkins globular. Ovary surrounded
by 8 long, linear, awl-shaped, hairy and glandular scales ■which,
encircle the ripened fruit. Nut nearly ovoid, smooth, small, but
eaten by children.
16. JUGLANDACEAi. Walnut Family
Trees with alternate, odd-pinnate leaves without stipules.
Flowers monoecious, the staminate in long and drooping cat-
kins ; stamens few or many ; calyx 2-6-parted. Fertile flowers
solitary or in small clusters; calyx .3-5-lobed, minute petals
sometimes present. Ovary inferior, 1-celled or incompletely
2-4-celled. Fruit (strictly speaking a drupe) with a dry husk
inclosing a bony nut.*
I. JUGLANS L.
Staminate catkins cylindrical, solitary, borne on wood of
the previous year; stamens numerous, filaments short; calyx
4-6-parted. Pistillate flowers single or a few together on a
short peduncle at the base of the growth of the, season. Calyx
4-parted. Petals 4, minute, epigynous. Styles 2, short, plumose.
Fruit large, roundish or oval, husk fibrous-fleshy, becoming
dry, indehiscent; nut bony, very rough.*WALNUT FAMILY.
53
1.	J. cinerea L. Butternut. Leaflets 15-19, ovate-lanceolate,
taper-pointed at the apex, rounded or slightly unsymmetrical at the
base, serrate, downy beneath ; petioles, branchlets, and fruit clothed
with short, sticky hairs. Fruit often somewhat in clusters, oblong,
large. More common northward. Wood less valuable and nut less
oily than the black walnut. The English walnut (/. regia) is
occasionally seen in cultivation. It has 7-11 leaflets and a nearly
smooth nut.*
2.	J. nigra L. Black Walnut. Leaflets 13-21, ovate-lanceolate,
serrate, taper-pointed, somewhat cordate or oblique at the base,
nearly smooth above, downy beneath; petioles minutely downy.
Fruit usually single, roundish, about 2 in. in diameter. On rich soil,
rare near the coast. One of the most valuable of our native trees,
the wood being very durable and highly prized for cabinet work.*
n. CARYA Nutt. (HICORIA)
Leaflets serrate. Staminate catkins usually in threes on a
common peduncle, or sometimes sessile at the base of the
growth of the season ; calyx 2-3-parted; stamens 3-10, fila-
ments short. Pistillate flowers 2-5 in terminal clusters;
calyx 4-parted ; petals none; styles 2 or 4, fringed. Fruit
somewhat globular, husk separating more or less completely
into 4 valves; nut smooth or angled.*
1.	C. illinoensis K. Koch. Pecan. A large tree with rough gray
bark, young twigs and leaves downy, nearly smooth when mature.
Leaflets 11—15, oblong-lanceolate, acuminate, serrate, scythe-shaped.
Staminate catkins nearly sessile, 5-6 in. long. Husk of fruit thin;
nut oval or oblong, thin-shelled. Hirer bottoms. Rarely native east
of the Mississippi River, but widely planted for its fruit.*
2.	C. ovata K. Koch. Shellbark Hickory. A large tree with
bark scaling off in long plates; young twigs and leaves downy, becom-
ing smooth with age. Leaflets 5, the lower ones oblong-lanceolate, the
upper one longer and obovate, taper-pointed at the apex, narrowed
to the sessile base. Inner bud scales becoming large and conspicu-
ous. Staminate catkins in threes. Fruit globose, husk thick, split-
ting into four sections; nut white, compressed, 4-angled, pointed,
thin-shelled. On rich soil; more common N. Wood strong and
elastic, but not durable when exposed.*
3.	C. laciniosa Loud. Big Shellbark, King Nut, Bull Nut. A
tree 70-90 ft. high, with shaggy bark. Leaflets 7 or 9, the terminal
one nearly sessile. Fruit large, ovoid or nearly so, 4-grooved towarij
the outer end, the husk very thick, nut pointed at each end, 14-2 in.54
KEY AND FLORA
long, thick-shelled, with a very sweet kernel. Wood hard and heavy.
Common in rich, damp soil W.
4.	C. alba K. Koch. Mocker Nut, White-Heart Hickory. A
large tree 70-100 ft. high, with close, rough bark; catkins, twigs,
and under surfaces of the leaves downy and resinous-scented when
young. Leaflets 7-9, oblong-lanceolate or obovate-lanceolate, taper-
pointed. Fruit globose or nearly so, with a very thick, hard husk; nut
with 4 ridges toward the apex, very thick-shelled, with a small, sweet
kernel. On rich hillsides. Wood much like that of C. ovala.
5.	C. cordiformis K. Koch. Pignut, Swamp Hickory. A me-
dium-sized tree, with rather smooth bark. Leaflets 7-11, lanceolate
or oblong-lanceolate. Fruit not large, husk thin; nut globular, with
a short point, very thin-shelled; kernel extremely bitter. Moist soil,
common in the Middle States.
17. BETULACE2E. Bircii Family'
Trees or shrubs with alternate, simple, petioled leaves, with
usually deciduous stipules. Flowers monoecious in cylindrical
or subglobose catkins. Staminate catkins drooping ; flowers
1-3 in the axil of each bract; calyx none or membranous
and 2-4-parted; stamens 2-10, distinct. Pistillate catkins
drooping, spreading, or erect and spike-like; flowers with or
without a calyx ; ovary solitary, 1-2-celled ; ovules 1-2 in each
cell. Fruit a 1-celled nut or a key.*
I. CORYLUS L.
Shrubs with prominently veined, cut-toothed leaves, which
are folded lengthwise in the bud. Flowers expanding before
the leaves. Staminate flowers in slender, drooping catkins ;
stamens 8, anthers 1-celled. Fertile flowers several in a
cluster or in very short catkins at the ends of the twigs of
the season ; ovary incompletely 2-celled; style short; stigmas
2; bractlets 2, becoming enlarged and inclosing the single
bony nut at maturity.*
1. C. americana Walt. Hazelnut. A shrub 2-5 ft. high; young
twigs and petioles covered with brownish, stiff hairs. Leaves not
very thin, round-cordate, acute or slightly taper-pointed, irregularly
toothed, nearly smooth above, downy below. Involucre longer thanBIRCH FAMILY
55
the nut and partially inclosing it. glandular-hairy. Xut 9ubglobose,
pointed, edible. On rich soil, borders of meadows and fields, and
in oak openings.
2. C. rostrata Ait. Beaked Hazelnut. A shrub 4-S ft. high.
Young twigs near ends smooth. Leaves thin, little if at all heart-
shaped, doubly serrate or incised, taper-pointed, stipules linear-
lanceolate. Involucre completely covering the nut and prolonged
into a beak beyond it. Common X. [The latter species is not
nearly as widely distributed as the former; they cannot be readily
distinguished from each other until the fruit is somewhat mature.
The principal points of difference discernible before the fruit is
nearly mature are the hairy twigs of Xo. 1 and the smooth ones of
Xo. 2, and the fact that Xo. 1 has buds rounded at the apes and
more slender and longer staminate catkins, while Xo. 2 has buds
acute at the apex and thicker and shorter staminate catkins.]
H. OSTRYA Scop.
Small trees with gray bark and very hard wood. Leaves
open and concave in the bud and somewhat plaited on the
veins. Staminate flowers on slender, drooping catkins, sessile
at the end of the growth of the previous season; stamens
3-12, subtended by a bract; filaments forked; anthers hairy.
Pistillate flowers surrounded by a tubular bractlet, which
becomes large and bladder-like at maturity. Fruit a small,
pointed, smooth nut; mature catkins hop-like.*
1. 0. virginiana K. Koch. A small tree with brownish, furrowed
bark. Leaves ovate, acute, doubly serrate, often inequilateral at the
base, short-pet.ioled. Staminate and fertile catkins 2-3 in. long. In
rich woods. Often known as “• ironwood ” and “ leverwood.” *
HI. CARPINUS L.
Trees with thin, straight-veined leaves, which are folded
in the bud. Flowers appearing before the leaves. Staminate
flowers in slender, drooping catkins, sessile at the end of the
growth of the previous season ; stamens 3-12, subtended by a
bract; filaments forked; anthers hairy. Pistillate catkins
spike-like, each pair of flowers subtended by a deciduous bract,
and each flower by a persistent bractlet, which becomes large
and leaf-like in fruit; ovary 2-celled, 2-ovuled; stigmas 2,
thread-like. Fruit a small, angular nut.*56
KEY AND FLORA
1. C. caroliniana Walt. Hornbeam. A small tree with smooth
and close gray bark; twigs slender. Leaves ovate-oblong, acute or
taper-pointed, sharply and doubly serrate, the straight veins termi-
nating in the larger serrations; downy when young and soon be-
coming smooth. Staminate catkins 1-1J in. long. Pistillate catkins
long-peduncled, 8-12-flowered ; bractlets becoming nearly 1 in. long,
cut-toothed, the middle tooth much longer than the others. In rich,
moist woods. Often known as “blue beech ” and “ironwood.”*
IV. BETULA L.
Trees with slender, aromatic twigs, and thin, usually straight-
veined leaves. Staminate catkins drooping, flowers usually 3
in the axil of each bract; stamens 4, short; anthers 1-celled.
Pistillate catkins erect, flowers 2 or 3 in the axil of each bract;
ovary sessile, 2-celled ; styles 2 ; bracts 3-lobed ; perianth none.
Nut broadly winged.*
1.	B. lenta L. Cherry Birch. Leaves ovate or oblong-ovate,
acute, heart-shaped, finely and doubly serrate, silky when young;
petioles about J in. long. Staminate catkins clustered, 3-4 in. long.
Pistillate catkins sessile, about 1 in. long; cylindrical bracts spread-
ing, acute, smooth. River banks, especially N. A large tree, with
aromatic twigs. The oil contained in the bark and twigs is distilled
and used as a substitute for wintergreen.*
2.	B. lutea Miclix. f. Yellow Birch. A large forest tree, some-
times 60-90 ft. high, with yellowish or silver-gray bark, which peels
off in extremely thin layers. Leaves ovate or nearly so, usually taper-
pointed, rounded or sometimes almost heart-shaped at the base,
sharply and finely serrate, somewhat downy on the veins beneath,
3-5 in. long. Staminate catkins 3-31 in. long; pistillate catkins
about | in. long. Rich woods N., also southward in the mountains.
3.	B. nigra L. River Birch, Red Birch. A medium-sized tree
with reddish-brown bark. Leaves rhombic-ovate, acute at the apex,
acute or obtuse at the base, sharply and doubly serrate, white-downy
below, becoming smoother with age, petioles short. Staminate catkins
2-3 in. long. Pistillate catkins 1-11 in. long, peduncles short, bracts
nearly equally 3-cleft, woolly. River banks, especially S. and IV.*
4.	B. populifolia Marsh. Gray Birch. A tall shrub or slender,
straggling tree, 15-30 ft. high, seldom growing erect, often several
trunks springing from the ground almost in contact and slanting
away from each other. Leaves triangular, with a long taper point
and truncate base, unevenly twice serrate, with rather long, slender
petioles, which allow the leaves to quiver like those of the aspen.BIRCH FAMILY
57
Bark scaling oft in white strips and layers, but not in nearly as
large sheets as that of the rarer canoe birch (B. papyrifera). The
commonest birch of New England.
5. B. alba L. European White Birch, Cut-Leaved Birch.
A tree 50-60 ft. high, often with drooping branches. Leaves
triangular-ovate, truncate, rounded or somewhat heart-shaped at
Fig. 11. Gray birch (Betula populifolia)
A, catkins, natural size: s, staminate; p, pistillate. B, cluster of ripened
fruits; C', bract with three staminate flowers; D. bract with three pistil-
late flowers; E, fruit. (B, 6', D, E, somewhat: magnified)
the base, not strongly taper-pointed except in the cut-leaved form.
Commonly cultivated from Europe. Resembles No. 4, but has whiter
bark and (the weeping form) much more slender branches.
Yar. papyrifera. Canoe Birch, Paper Biiich. A large tree,
often 60-7 0 ft. high, with chalky-white papery bark, peeling off in
large thin sheets. Leaves ovate, acute or taper-pointed, coarsely
serrate or dentate, but entire at the base, dark green and usually
without glands on the upper surface, on the lower surface light
yellowish-green and nearly smooth, but with tufts of hairs in the58
KEY AND FLORA
forks of the veins and numerous black glands, 2-3 in. long, with
slender petioles. Staminate catkins 3-4 in. long; pistillate catkins
1-14 in. long, peduncles 2-bracted. Rich soil on hillsides, along
streams, and near lakes and swamps, X. and N.E. The beautiful
bark is much used by the Indians for canoes, for basket making,
and for other purposes.
V. ALNUS Hill
Shrubs or small trees. Leaves petioled, serrate. Flower
buds stalked, appearing the previous season ; staminate cat-
kins racemed, drooping; flowers 3-6 in the axil of each bract,
subtended by 1-2 bractlets; perianth 4-parted; stamens 4; fila-
ments short. Pistillate catkins erect; flowers 2-3 in the axil
of each bract; perianth replaced by 2-4 minute bractlets which
are adherent to the bract. Ovary 2-celled; styles 2. Fruit a
winged or angled nut; bracts of the pistillate flowers some-
what fleshy, persistent, becoming woody in fruit.*
1.	A. incana Moench. Speckled Alder. A shrub 8-20 ft. high.
Leaves broadly oval or ovate, rounded at the base, sharply (some-
times doubly) serrate, white and usually downy beneath. Fruit
round. Forming thickets by streams, very common N.
2.	A. rugosa Spretig. Smooth Alder. A shrub or small tree with
smooth bark. Leaves obovate, rounded or obtuse at the apex, acute
at the base, sharply and minutely serrate, smooth above, downy be-
neath, petioled; stipules oval, deciduous. Staminate catkins 2-4 in.
long ; fruiting catkins ovoid, short-peduncled. Fruit ovate, wingless.
Banks of streams and borders of marshes, ranging far S. Leaves
often persistent during the winter.*
18. FAGACEiE. Beech Family
Trees or shrubs. Leaves alternate, simple, pinnately veined ;
stipules deciduous. Flowers mono3cious,the staminate in heads,
or in drooping, spreading, or erect catkins ; calyx minute ; petals
none ; stamens 4-20. Pistillate flowers solitary or in small
clusters, each flower subtended by more or less united bracts,
which at maturity form a cup or bur ; calyx minutely toothed;
petals none ; ovary 2-7-celled, but becoming 1-eelled. Fruit a
1-seeded nut.*BEECH FAMILY
59
I. FAGUS L.
Trees with smooth, close, ash-gray bark, and slender, often
horizontal, branches. Staminate flowers in long, slender-pedun-
cled, roundish clusters ; calyx bell-shaped, 4-6-cleft; stamens
8-12 ; anthers 2-celled. Pistillate flowers solitary or more often
in pairs, peduncled, surrounded by a 4-lobed involucre and
numerous linear bracts ; ovaries 3-celled, with 2 ovules in each
cell, but usually only 1 ovule maturing in each ovary ; styles 3,
thread-shaped. Fruit a thin-shelled, 3-angled nut.*
1.	F. grandifolia Ehrh. Beech. Large trees. Leaves oblong-ovate,
taper-pointed at the apex, serrate, straight-veined, very white-silky
when young, nearly smooth with age. Involucre densely covered with
short recurved spines. Nuts thin-shelled, edible. Common on damp
soil everywhere. The wood is very hard, tough, and close-grained,
and is especially valuable for the manufacture of small tools.*
2.	F. sylvatica L. The European beech is occasionally found
planted as a shade tree. The variety known as the copper beech
is most usual, and is readily recognized by its dark, crimson-purple
leaves.
II. CASTANEA Hill
Trees or shrubs with rough, gray, rather close bark. Leaves
straight-veined, undivided, prominently toothed. Flowers ap-
pearing later than the leaves. Staminate catkins erect or
spreading, loosely flowered, flowers several in the axil of each
bract; calyx 4-6-parted; stamens 8-16. Pistillate flowers at
the base of the staminate catkin or in small separate clus-
ters, usually 3 in each involucre; ovary 4-celled, surrounded
by 5-12 abortive stamens. Fruit a 1-celled nut inclosed in
the greatly enlarged and very prickly involucre.*
1.	C. dentata Borkh. American Chestnut. A large tree, bark
somewhat rough, and splitting into longitudinal plates. Leaves
oblong-lanceolate, taper-pointed at the apex, usually acute at the
base, coarsely and sharply serrate with ascending teeth, smooth, dark
green above, lighter below; petioles stout, short. Staminate catkins
erect, 6-10 in. long. Xuts usually 3 in each bur. Rich soil, especially
N. Rarely found on soils containing much lime.*
2.	C. pumila Mill. Chinquapin. A small tree or shrub. Leaves
oblong, acute or obtuse at both ends, serrate with divergent teeth,
dark green and smooth above, white-woolly below. Nuts solitary,
nearly globular. Common southward in rich woods.*60
KEY AND FLORA
in. QUERCUS L.
Trees or shrubs with entire, serrate, or lobed leaves, which
are often persistent. Staininate flowers in slender catkins,
each subtended by quickly deciduous bracts, and consisting
of 3-12 stamens inclosed by a 4-8-parted perianth, often
containing an abortive ovary. Pistillate flowers solitary or
in small clusters, each consisting of a 3-celled ovary with
2 ovules in each cell, though rarely more than 1 ovule
matures; styles short, erect, or recurved. Pistillate flowers
surrounded by a scaly involucre which at maturity becomes
a cup inclosing the base of the fruit or sometimes a large
part of it. Fruit an ovoid or subglobose, 1-seeded, thin-
shelled nut (acorn).
A. Fruit annual; leaves not bristle-tipped, though often
mucronate.
1.	Q. alba L. White Oak. A large tree with light gray bark.
Leaves obovate-oblong, 3-9-lobed, lobes rounded and mostly entire,
bright green above, paler below, short-petioled. Cup hemispherical,
scales rough, woolly when young, but becoming smooth with age ;
acorn oblong-ovate, about 1 in. long. Common in damp soil. Wood
strong and durable ; one of the most valuable timber trees.*
2.	Q. stellata Wang. Post Oak. A tree of medium size with
rough gray bark. Leaves broadly obovate, deeply lyrate-pinnatifid
into 5-7 rounded, divergent lobes, upper lobes much the longer,
smooth above, yellowish-downy beneath; petioles about 1 in. long.
Cup hemispherical, nearly sessile ; acorn ovoid, 2-3 times as long as
the cup. On dry soil. Wood hard and valuable.
3.	Q. lyrata Walt. Swamp Oak. A large tree with gray or red-
dish bark. Leaves obovate-oblong, deeply pinnatifid, lobes narrow,
often toothed, thin, smooth above, white, densely woolly beneath.
Cup round-ovate, scales cuspidate, inclosing nearly the whole of the
depressed-globose acorn. On wet soil. Wood strong and very durable.*
4.	Q. macrocarpa Michx. Bur Oak. A medium-sized to very large
tree, with roughish gray bark. Leaves obovate or oblong, lyrately
and deeply sinuat.e-lobed, smooth above, pale and downy beneath.
Cup very deep and thick, abundantly fringed about the margin, 2 in.
in diameter. Acorn, half or more (sometimes entirely) inclosed by
the cup. Reaches its full size only on rich bottom lands S. and W.,
where it becomes one of the finest timber oaks. Wood very hard
and heavy.BEECH FAMILY
61
5.	Q. Muhlenbergii Engelm. Yellow Chestnut Oak. A tree of
medium or large size with gray bark. Leaves oblong or oblanceolate,
usually acute at the apex and obtuse or rounded at the base, coarsely
and evenly toothed; veins straight, impressed above and prominent
beneath ; petioles slender. Cup hemispherical, sessile or short-pedun-
oled, with flat scales, \ in. broad, inclosing about half the ovoid
acorn, which is j-f in. long. Common on dry soil. Wood close-grained,
durable, and valuable.
6.	Q. Prinus L. Swamp Chestnut Oak. A large tree With brown,
ridged bark. Leaves oblong or oblong-lanceolate, rather obtuse, cre-
nately toothed, minutely downy beneath; petioles slender, about 1 in.
long. Cup hemispherical, peduncles longer than the petioles, scales
acute, tubercular, appressed; acorn oblong, acute, 1 in. or less in
length, edible. Common on low ground. Wood strong and valuable.*
7.	Q. virginiana Mill. Live Oak. A large tree with rough gray
or brown bark and a low, spreading top. Leaves leathery, evergreen,
oblong or oblanceolate, often somewhat 3-lobed on young trees,
margin rolled under, dark green and shining above, pale below;
petioles short, stout. Fruit often in short racemes, cup top-shaped,
scales closely appressed. hoary, peduncles 1-1 in. long; acorn from
subglobose to oblong, the longer form occurring on the younger
trees. On low ground near the coast. WTood very hard aud durable;
valued for shipbuilding.*
B. Fruit biennial; leaves entire or with bristle-pointed
lobes.
8.	Q. rubra L. Red Oak. A large tree. Leaves oval or obovate,
green above, pale and slightly downy beneath; sinuses shallow and
rounded, lobes 8-12, taper-pointed; petioles long. Cups saucer-shaped,
with fine scales; acorn ovate or oblong, about 1 in. long. Common ;
wood not valuable ; leaves turning red after frost and often remain-
ing on the tree through the winter.
9.	Q. velutina Lam. Black Oak. A large tree with rough, dark
brown outer bark and thick, bright yellow inner bark. Leaves broadly
oval, usually cut more than halfway to the midrib, sinuses rounded;
lobes about 7, sharply toothed at the apex, smooth above, usually
downy on the veins beneath; cup hemispherical or top-shaped, with
coarse scales, short-peduueled, inclosing about half the roundish
acorn. Common ; wood not valuable, but the inner bark used for
tanning and dyeing.*
10.	Q. falcata Michx. Spanish Oak. A small or medium-sized
tree with leaves 3-5-lobed at the apex, obtuse or rounded at the base,
grayish-downy beneath, lobes lanceolate and often scythe-shaped,62
KEY AND FLORA
sparingly cut-toothed. Cup top-shaped, with coarse scales, inclosing
about half the nearly round acorn. Common in dry woods. Foliage
quite variable in outline and lobing; bark valuable for tanning.*
11.	Q. nigra L. Black-Jack Oak. A small tree; leaves obovate,
usually with three rounded lobes at the apex, the lobes bristle-pointed,
rounded, or slightly cordate at the base, rusty-pubescent beneath,
shining above, coriaceous, short-petioled; cup top-shaped, short-
peduncled, .with coarse and truncate scales, inclosing about one
third of the oblong-ovate acorn. An almost worthless tree, its
presence indicating a thin and sterile soil.*
12.	Q. phellos L. Willow Oak. A tree of medium size, leaves
lanceolate or elliptical, scurfy when young and becoming smooth
with age, very short-petioled ; cup shallow, sessile ; acorn subglobose.
Wet soil. Often planted for shade.*
19. ULMACEiE. Elm Family
Trees or shrubs with watery juice ; alternate, simple, petio-
late, serrate, stipulate leaves, which are usually 2-ranked; and
small, bisexual, or somewhat monoecious, apetalous flowers.
Calyx of 3-9 sepals, which are distinct or partly united;
stamens as many as the sepals and opposite them. Ovary
1-2-celled; styles 2, spreading. Fruit a key, nut, or drupe.*
I. ULMUS L.
Trees with straight-veined, unsymmetrical, doubly serrate
leaves; stipules early deciduous. Flowers bisexual; calyx
bell-shaped, 4-9-cleft. Stamens slender, protruding. Ovary
compressed; styles 2, spreading. Fruit membranaceous, flat,
winged on the edge.*
1.	U. fulva Michx. Slippery Elm. A tree of medium size, with
rough, downy twigs, and rusty, densely woolly bud scales. Leaves
large, thick, very rough above, downy beneath, ovate or obovate, taper-
pointed at the apex, unsymmetrical, obtuse or somewhat cordate at
the base, coarsely and doubly serrate ; calyx lobes and pedicels downy.
Fruit broadly oval, downy over the seed, the wing smooth. Inner
bark very fragrant when dried, and a popular domestic remedy.*
2.	U. campestris L. English Elm. A large tree, with short,
rather upright or ascending branches. Leaves not bilaterally sym-
metrical, ova), acute or sometimes a little taper-pointed, doublyELM FAMILY
63
serrate, 3-4 in. long. Flowers in close clusters with very short pedi-
cels. Fruit obovate-elliptical, with a fissure extending almost to the
seed, nearly smooth and not ciliate. Considerably planted as a shade
tree and rarely escaped from cultivation. Very variable, one variety
with thick ridges of cork on the twigs.
3. U. americana L. White Elm. A large tree with gray bark,
drooping branches, and smooth or slightly downy twigs. Leaves oval
or obovate, abruptly taper-pointed at the apex, obtuse and oblique at
the base, slightly rough above, soft-downy or soon smooth beneath.
Flowers in close fascicles; pedicels slender, smooth. Fruit oval or
obovate, with 2 sharp teeth bending toward each other at the apex;
Fig. 12. Ulmus campestris
A, a flowering twig; B, a flower; C, longitudinal section of a flower; D, a
fruit. (A, D, natural size; B, O', enlarged.) (After Wossidlo)
wing reticulate-veined, downy on the margin. In moist, rich soil.
A widely planted ornamental tree; wood strong but warping badly,
and not durable when exposed.*
4.	U. racemosa Thomas. Cork Elm, Rock Elm. A large tree 80-
100 ft. high, with the young twigs somewhat downy; the branches
often with ridges of cork. Leaves much as in U. americana, but
smaller and less sharply serrate. Flowers racemed, on thread-like
pedicels. Fruit oval, downy on the surface and densely ciliate.
In rich soil, especiallj' along river banks. A highly valuable timbei-
tree.
5.	U. alata Michx. Winged Elm. A small tree with branches
corky-winged. Leaves small, ovate-lanceolate, acute, sharply serrate,
base nearly equal-sided, rough above, downy beneath, nearly sessile.64
KEY AND FLORA
Flowers in small clusters. Fruit oblong, downy on the sides, ciliate
on the edges. On rich soil. Occasionally producing a second set of
flowers and fruit from September to November.*
II. CELTIS L.
Trees or shrubs with entire or serrate, petiolecl leaves.
Flowers greenish, axillary, on wood of the same season, the
staminate in small clusters, the fertile single or 2-3 together.*
1.	C. occidentalis L. Hackberry. A large or medium-sized tree,
having much the appearance of an elm, bark dark and rough.
Leaves ovate, taper-pointed at the apex, abruptly obtuse and inequi-
lateral at the base, sharply serrate, often 3-nerved from the base,
smooth above, usually somewhat downy below. Fruit a small, dark-
purple drupe. On rich soil.
2.	C. mississippiensis Bose. Southern FIackberry. A tree
usually smaller than the preceding, bark gray, often very warty.
Leaves broadly lanceolate or ovate, long taper-pointed at the apex,
obtuse or sometimes heart-shaped at the base, entire or with very
few serratures, smooth on both sides, 3-nerved. Fruit a purplish-
black, globose drupe.*
20. MORACEAE. Mulberry Family
Trees, shrubs, or herbs, usually’ with milky juice, alternate
leaves, large deciduous stipules, and small monoecious or dke-
cious flowers crowded in spikes, heads, or racemes, or inclosed
in a fleshy receptacle. Staminate flowers with a usually 4-lobed
calyx, and with as many stamens opposite the lobes; filaments
usually inflexed in the bud, straightening at maturity. Pistil-
late flowers usually 4-sepalous ; ovary 1-2-celled, 1-2-ovuled;
styles 2; receptacle and perianth often fleshy at maturity.*
I. MORUS L.
Trees or shrubs with milky juice, rounded leaves, and monoe-
cious flowers in axillary spikes. Staminate flowers rvith a
4-parted perianth, and 4 stamens inflexed in the bud. Pistil-
late flowers with a 4-parted perianth, which becomes fleshy in
the multiple fruit, the pulpy part of which consists of theMULBERRY FAMILY
65
thickened calyxes of many flowers; ovary sessile; stigmas 2,
linear, spreading; the fleshy perianth inclosing the ovary at
maturity.*
1.	M. rubra L. Red Mulberry. A small tree. Leaves cordate-
ovate, often 3-5-lobed on vigorous shoots, taper-pointed at the apex,
serrate, rough above, white, densely woolly beneath. Mature fruiting
spikes oblong, drooping, dark red or purple, edible. On rich soil.
Wood very durable, bearing exposure to the weather.
2.	M. alba L. White Mulberry. A small tree. Leaves ovate,
heart-shaped, acute at the apex, rounded and often oblique at
the base, serrate or sometimes lobed.
Smooth and shining on both sides.
Mature fruit light red or white. In-
troduced and common about old
dwellings.*
II. MACLURA Nutt. (TOXYLON)
A small tree with milky juice.
Leaves alternate, petioled, spines
axillary. Flowers dioecious. Stam-
inate flowers in short axillary ra-
cemes; calyx 4-parted; stamens 4,
inflexed in the bud. Pistillate flow-
ers in axillary, peduncled, capitate clusters ; calyx 4-parted ;
ovary sessile ; style long; calyxes becoming thickened and fleshy
in fruit and aggregated into a large, dense, globular head.*
1. M. pomifera Schneider. Osage Orange. A small tree with
ridged, yellowish-brown bark. Leaves minutely downy when young,
becoming smooth and shining with age, ovate or ovate-oblong, taper-
pointed at the apex, obtuse or subcordate at the base, entire, petioled.
Staminate racemes about 1 in. long. Pistillate flower clusters about
1 in. in diameter. Fruit yellowish, tubercled, 8-4 in. in diameter.
In rich soil. Xative in Texas and extensively planted for hedges.
Wood very durable when exposed to the weather, and therefore used
for fence posts. As the wood does not swell or shrink with changes
in its moisture, it is highly valued for wheel hubs, etc.*
HI. BROUSSONETIA L’Her.
Small trees with milky juice. Leaves alternate, pjetioled.
Flowers dioecious; staminate in cylindrical spikes, with a
Fig. 13. Moms alba
A, staminate flower, about four
times natural size; B, cluster
of pistillate flowers. (After
Warming)66
KEY AND FLORA
4-cleft calyx, 4 stamens, and a rudimentary ovary; pistil-
late flowers in capitate clusters, calyx 3-4-toothed. Ovary
stalked; style 2-cleft. Fruit in a globular head.*
1. B. papyrifera Vent. Paper Mulberry. A round-topped tree
with yellowish-brown bark. Leaves cordate, often irregularly 2-3-
lobed," serrate, rough above, downy beneath, long-petioled. Staminate
spikelets peduncled, 2-3'in. long. Pistillate heads stout, peduncled,
about 1 in. in diameter. Introduced from Asia and very common S.
about old dooryards.*
IV. CANNABIS L.
Coarse herbs with very tough, fibrous bark. Leaves usu-
ally opposite, palmately compound. Flowers small, dioecious,
greenish, the staminate ones in compound racemes or panicles,
the pistillate ones in spikes. Calyx of the staminate flowers of
5 sepals, that of the pistillate flowers of 1 large sepal which
covers the ovary and the akene.
1. C. sativa L. Common Hemp. An erect plant, 4-8 ft. high.
Leaves large, petioled, of 5-7 lanceolate, irregularly serrate or toothed
leaflets. Cultivated from Europe, S. and W., for its fiber, and some-
times runs wild along roadsides in rich soil.
21. URTICACEA5. Nettle Family
Herbs with watery juice, stem and leaves often clothed with
stinging hairs. Leaves undivided, stipulate. Flowers small,
greenish, unisexual, apetalous in axillary clusters. Calyx of
the staminate flowers 4-5-parted or 4-5-sepalous ; stamens as
many as the sepals and opposite them; filaments inflexed in
the bud and straightening at maturity ; anthers 2-celled. Calyx
of pistillate flowers 2-4-sepalous; ovary sessile, 1-celled;
stigma simple or tufted. Fruit an akene commonly inclosed
in the dry, persistent calyx.*
URTICA L.
Annual or perennial herbs. Leaves with stinging hairs,
opposite, petioled, several-nerved, dentate or incised, stipulate.
Flowers monoecious or dioecious. Calyx of the staminateSANDALWOOD FAMILY
67
flowers 4-parted; stamens 4, inserted around a rudimentary-
ovary. Pistillate flowers with 4 unequal sepals, the inner
ones dilated in fruit; akenes smooth, compressed.*
1.	U. gracilis Ait. Slender Nettle. Perennial, slender, with
some stinging hairs, 2-6 ft. high. Leaves ovate-lanceolate or nar-
rower, with slender petioles, taper-pointed, sharply serrate, with 3-5-
nerves arising from the rounded or sometimes almost heart-shaped
base, almost smooth ; stipules lanceolate. Flower clusters in branch-
ing panicled spikes, longer than the petioles. Flowers dioecious or
bisexual.
2.	U. urens L. Small Nettle. Annual; stem stout, Dangled,
hairy, 12-18 in. tall, with few stinging hairs; branches slender.
Leaves elliptical or ovate, serrate or incised, 3-5-nerved, acute or
obtuse at the ends, thin, hairy; petioles often as long as the blades;
stipules short. Flower clusters axillary, in pairs, loose, mostly shorter
than the petioles. On damp soil in waste places. Naturalized from
Europe.
22. SANTALACE4E. Sandalwood Family
Herbs, shrubs, or trees with entire leaves. Flowers usually
small. Calyx 4-5-cleft, its limb epigynous. Corolla wanting.
Stamens as many as the calyx lobes and opposite them,
inserted on the margin of a fleshy disk. Style 1; ovary
1-celled, with 2-4 ovules borne at the top of a free central
placenta. Fruit 1-seeded.
COMANDRA Nutt.
Low, smooth perennials with herbaceous stems, rather
woody below, often parasitic. Leaves alternate and nearly
sessile. Flowers nearly white, in small umbel-like clusters,
bisexual. Calyx bell-shaped at first. Stamens borne on a
5-lobed disk which surrounds the pistil; anthers connected
by a tuft of hairs to the calyx lobes.
1. C. umbellata Nutt. Bastard Toadflax. Plant 8-10 in. high,
with very leafy stems. Roots attached to the roots of trees, from
which they draw nourishment. Leaves oblong or oblanceolate, pale,
nearly 1 in. long. LTmbel-like clusters about 3-flowered, longer than
the leaves. Rocky, dry woods.68
KEY AND FLORA
23. LORAWTHACEAL Mistletoe Family
Parasitic shrubs or herbs, leaves opposite, leathery, without
stipules. Flowers monoecious or dioecious, clustered or solitary ;
perianth of both calyx and corolla, or of a calyx only, or some-
times wanting, the limb epigynous ; sepals 2-8. Stamens as
many as the sepals, and opposite them. Ovary 1-celled; ovule 1.
Fruit a berry.*
PHORADENDRON Nutt.
Evergreen, shrubby plants, parasitic on trees; branches
greenish, jointed, and very brittle. Leaves leathery. Flowers
dioecious, in short jointed spikes. Staminate flowers globular,
calyx 2-4-lobed, stamens sessile at the base of the lobes,
anthers transversely 2-celled. Stigma sessile. Berry 1-seeded.*
1. P. flavescens Nutt. American Mistletoe. Very round, bushy;
branches very brittle at the joints, opposite or whorled, 6 in. to 2 ft.
long. Leaves flat, leathery, or somewhat fleshy, nearly veinless, obo-
vate, entire, with short petioles. Flowering spikes solitary or 2-3
together in the axils of the leaves. Berry roundish, white, glutinous.
Parasitic on many deciduous trees.*
24. ARISTOLOCHIACE.®. Dutchman’s Pipe Family
Herbaceous plants, apparently stemless or with twining and
leafy stems. Leaves alternate, without stipules, petioled,
mostly roundish or kidney-shaped. Flowers axillary, solitary
or clustered, bisexual. Calyx tubular, 3- or 6-lobed, usually
colored. Petals none. Stamens 6-12, epigynous. Pistil 1;
ovary mostly 6-celled, many-seeded.*
I. ASARUM L.
Perennial, apparently stemless, aromatic herbs, with slen-
der, branching rootstocks. Leaves long-petioled, from kidney-
shaped to halberd-shaped. Flowers axillary, peduncled. Calyx
aetinomorphic, 3-lobed, withering-persistent. Stamens 12, the
filaments partially united with the style and usually prolonged
beyond the anthers. Ovary 6-celled, with parietal placentfe,
many-seeded. Mature capsule roundish, often somewhat fleshy.*BUCKWHEAT FAMILY
69
1.	A. canadense L. Wild Ginger. Plant soft-hairy. Leaves 2,
large, kidney-shaped, on long petioles, with the flower borne on a
short peduncle between them. Flower greenish outside, brownish-
purple inside. Calyx lobes epigynous, taper-pointed, widely spread-
ing, relaxed at the tip. Rich, shady woods, common N.
2.	A. virginicum L. Virginia Asarum. Leaves evergreen, 1-3
to each plant, smooth, mottled, round-cordate, entire, 2-3 in. long
and broad; petioles smooth or downy along one side, 3-7 in. long.
Flowers nearly sessile, greenish without, dull purple within, f-f in.
long; tube inflated below, narrow at the throat, lobes spreading.
Rich, shady woods.*
n. ARISTOLOCHIA L.
Erect or twining perennial herbs or woody vines. Leaves
alternate, heart-shaped at the base, palmately nerved, petioled,
entire. Flowers zygomorphic, solitary, or in small clusters.
Calyx perigynous or epigynous, tubular, irregular. Stamens
mostly 6, sessile, apparently united to the angled and fleshy
3-6-lobed or -angled stigma. Capsule naked, 6-valved; seeds
very numerous.*
1.	A. macrophylla Lam. Dutchman’s Pipe, Pipe Vine. A tall
climber. Leaves dark green, smooth, round-kidney-shaped, some-
times 1 ft. wide. Peduncles 1-flowered, with a single clasping bract.
Calyx 1J in. long, bent into the shape of a pipe, its border abruptly
spreading, brownish-purple. Rich woods, often cultivated.
2.	A. tomentosa Sims. Dutchman's Pipe. Stem woody, climb-
ing high, branches and leaves densely woolly. Leaves heart-shaped,
prominently veined, 3-5 in. long and broad. Flowers axillary, mostly
solitary, on slender peduncles. Calyx bent in the shape of a pipe,
vellowish-green with a dark purple throat, limb unequally 3-lobed,
rugose, reflexed. Anthers in pairs below the 3 spreading lobes of the
stigma. Capsule oblong. Stems sometimes 30 ft. long. Rich woods S.*
25. P0LYG0NACE2E. Buckwheat Family
Herbs with alternate, entire leaves, and usually with sheathing
stipules above the swollen joints of the stem. Flowers apeta-
lous, generally bisexual, with a 3-6-cleft calyx, generally colored
and persistent. Fruit a compressed or 3-angled akene, inclosed
in the calyx; seeds with endosperm, which does not generally
inclose the embryo. Stamens 4-12, on the base of the calyx.70
KEY AND FLORA
I. RUMEX L.
Coarse herbs, many of them troublesome weeds. Flowers
small, usually green or greenish, generally in whorls borne in
panicled racemes. Calyx of 6 nearly distinct sepals, the 3
inner ones larger and more petal-like than the 3 outer, and one
or more of them usually with a little knob or tubercle on its
back. Stamens 6; styles 3; stigmas short, fringed. Fruit a
3-angled akene, closely covered by the 3 inner calyx lobes,
enlarged and known as valves.
1.	R. crispus L. Yellow Dock. Stout, smooth, 3-4 ft. high.
Leaves lanceolate, margins very wavy, acute, the lower more or
less heart-shaped. Root long, tapering gradually downward, yellow,
very tough. Flowers in whorls crowded in long, straight, slender
racemes. Valves roundish-heart-shaped, mostly tubercled. A very
hardy weed, naturalized from Europe.
2.	R. verticillatus L. Swamp Dock. Perennial. Stem stout, smooth,
erect or ascending, 3-5 ft. tall. Lower leaves oblong, obtuse at the
apex and usually heart-shaped at the base, long-petioled, often 12-18
in. long; upper leaves narrower and often acute at both ends. Flowers
bisexual or somewhat monoecious, in dense whorls; pedicels slender,
J-f in. long, tapering downward, reflexed at maturity. Calyx green,
the valves broadly triangular, abruptly pointed, reticulated, a distinct
long and narrow tubercle on the back of each. Swramps and wet
ground.*
3.	R. Acetosella L. Sheep Sorrel. Perennial herbs with slender
creeping and bud-bearing roots. Stem simple or branched, smooth.
Leaves petioled, narrowly halberd-shaped, usually widest above the
middle, the apex acute or obtuse; upper stem leaves often nearly
linear and not lobed. Flovrers dioecious, small, in terminal, naked,
panicled, interrupted racemes. Calyx greenish ; the pistillate pani-
cles becoming reddish. Fruit less than TV in. long, granular, longer
than the calyx. A common weed, naturalized from Europe, in dry
fields and on sour soils. Foliage very acid.*
II. POLYGONUM L.
Annual or perennial, terrestrial or aquatic herbs, with en-
larged joints and simple, alternate, entire leaves; the sheath-
ing stipules often cut or fringed. Flowers bisexual, usually
white or rose-colored, each flower or cluster subtended by a
membranaceous bract similar to the stipules of the leaves.BUCKWHEAT FAMILY
71
Calyx mostly 5-parted, the divisions petal-like, erect and per-
sistent. Stamens 3-9; styles 2-3-parted. Fruit lens-shaped
or 3-angled.*
1.	P. aviculare L. Knotgrass. Annual or perennial. Stem pros-
trate or ascending, diffuse, smooth, 6-‘24 in. long. Leaves small,
lanceolate or linear-oblong, obtuse, nearly or quite sessile. Sheaths
thin and dry, 2-3-cleft or cut. Flower clusters axillary, 1-5-flowered ;
flowers inconspicuous, nearly sessile. Calyx greenish-white, 5-parted,
the lobes with white or colored borders. Stamens 5-8 ; style 3-parted.
Akene 3-angled, not shining. A common weed in dooryards and where
the ground is trampled.*
2.	P. lapathifolium L. Annual. Stem branching, 1-4 ft. high.
Leaves lanceolate or broader, wedge-shaped at the base and taper-
ing from near the base to an extremely slender point, ciliate, vary-
ing greatly in length. Sheaths not ciliate or fringed. Spikes oblong
to -linear, closely flowered, erect or nearly so, 1-2 in. long. Calyx
white or pink. Stamens 6 ; style 2-cleft. Akene ovate, lens-shaped,
TU in. wide or less. In wet soil.
3.	P. acre HBK. Water Smartweed. Perennial. Smooth or
nearly so; stems erect or ascending, rooting below, 2-5 ft. high.
Leaves lanceolate or broader, tapering at both ends, petioled, ciliate,
translucent-dotted, acrid, 11-8 in. long. Sheaths cylindrical, falling
early, bristly-fringed. Spikes erect or nearly so, loosely flowered, 3
in. long. Calyx whitish-greenish or flesh color. Stamens S ; style
usually 3-parted. Akene oblong, lens-shaped, smooth and shining.
Swamps and wet soil, especially S.
4.	P. Persicaria L. Lady’s Thumb. Annual. Smooth or nearly so.
Stem erect or ascending, 6-24 in. high. Leaves lanceolate or nar-
rower, tapering at both ends, usually with a dark triangular or cres-
cent-shaped spot near the center, very variable in length. Sheaths
more or less bristle-fringed. Spikes ovoid or oblong, dense, erect,
peduncled, |—2 in. long. Calyx pink or purple. Stamens usually 6;
styles 2-3-cleft more than half their length. Akene broadly ovate
and lens-shaped, often somewhat triangular, smooth and shining. In
waste ground, often a troublesome weed. Naturalized from Europe.
5.	P. hydropiperoides Michx. Mild Water Pepper. Perennial.
Stem smooth, slender, erect, decumbent, or prostrate, 1-3 ft. long.
Leaves usually narrowly lanceolate, but variable, acute, ciliate, 2-6
in. long. Sheaths wrinkled, bristle-fringed. Spikes erect, slender,
often with the flowers scattered,	in. long. Calyx pale pink,
greenish or nearly white. Stamens 8 ; style 3-parted more than half
its length. Akene 3-angled, smooth and shining. In swamps and
wet places, especially S.72
KEY AND FLORA
6. P. dumetorum L. False Buckwheat. Perennial. Stems slen-
der, twining, branched, 2-10 ft. long. Leaves ovate, taper-pointed,
heart-shaped to halberd-shaped at the base, long-petioled. Stipules
cylindrical, truncate. Flowers in axillary, more or less compound and
leafy racemes. Calyx greenish-white, the outer lobes winged and form-
ing a margin on the pedicel. Stamens 8. Stigmas 3. Akene 3-angled,
black, smooth, and shining. Margins of fields and thickets.*
III. FAGOPYRUM Hill
Smooth annual herbs, with more or less triangular leaves;
the sheathing stipules cylindrical or funnel-shaped. Flowers
bisexual, white, greenish or tinged with rose color, in terminal
or axillary, often panicled, racemes. Calyx petal-like (Fig. 14),
5-parted. Stamens 8. Styles 3, with knobbed stigmas. Akene
3-angled, much longer than the persistent calyx (Fig. 14).
Fig. 14. Buckwheat (Fagopyrum esculentum)
A, flower; B, section of flower; C, fruit. (All somewhat magnified.)
(After Marcliand)
1. F. esculentum Mxench. Buckwheat. Annual, nearly smooth.
Leaves halberd-shaped, 1-3 in. long. Flowers white or nearly so, with
8 yellow nectar-bearing glands between the stamens. Oldfields and
thickets, escaped from cultivation. Introduced from Europe or west-
ern Asia.
26. CHEN0P0DIACE2E. Goosefoot Family
Herbs or shrubs. Leaves simple, alternate, without stipules.
Flowers small, actinomorphic, either bisexual or more or less
monoecious or dioecious. Calyx free from the ovary. Corolla
wanting. Stamens usually 5, opposite the sepals. Styles or
stigmas generally 2. Fruit with 1 seed, usually inclosed in a
small, bladdery sac, sometimes an akene.GOOSEFOOT FAMILY
73
I. SPINACIA L.
Herbs. Flowers dioecious, in close axillary clusters. Stami-
nate flowers 3-5-sepaled, with 4 or 5 projecting stamens; pis-
tillate, flowers with a tubular 2-tootlied or 4-toothed calyx.
1. S. oleracea Mill. Spinach. A soft annual or biennial herb.
Leaves triangular, ovate, or halberd-shaped, petioled. Cultivated
from Asia as a pot herb.
II. CHENOPODIUM L.
Annual or perennial herbs. Stems erect or spreading.
Leaves alternate, usually white-mealy. Flowers small, green-
ish, in panicled spikes. Calyx 3-5-parted, the lobes often
slightly fleshy and keeled. Stamens 5; filaments thread-
shaped. Styles 2-3, distinct or united at the base. Seed
lens-shaped.*
1. C. Botrys L. Jerusalem Oak. A low, spreading plant, covered
with sticky down. Leaves with slender petioles, oblong, sinuately
Fig. 15. Pigweed (Chenopoclium album)
.1, B, flower; C, fruit. (All about seven times natural size)
lobed or the lobes pinnate. Flowers in loose, diverging, leafless ra-
cemes. The whole plant is sweet-scented. Introduced from Europe
and naturalized in gardens and along roadsides.
2.	C. glaucum L. Oak-Leaved Goosefoot. Annual, succulent,
somewhat mealy. Stem spreading, much branched, 5-12 in. high.
Leaves varying from oblong to lanceolate, obtuse, some or all of
them more or less sinuate-toothed, 1-2 in. long. Flower clusters
mostly small axillary spikes. A common weed. Naturalized from
Europe.
3.	C. album L. Lamb’s Quarters. Common Pigweed. Annual,
somewhat mealy. Stem erect, usually branching, 1-4 ft. high. Leaves74
KEY AND FLORA
varying from rhombic-ovate to (the uppermost) nearly linear, nar-
rowed at the base, acute, somewhat angulate-toothed, 1-4 in. long.
Spikes terminal and in the leaf axils, often panicled. Calyx with
keeled lobes, in fruit nearly covering the smooth seed. A common
and troublesome weed. Naturalized from Europe.
4. C. urbicum L. Upright Goosefoot. Annual, little or not at
all mealy. Stem stout, erect, and with erect branches, 1-3 ft. high.
Leaves halberd-shaped or triangular, acute, coarsely and sharply
toothed, except the upper ones, the larger ones 3-6 in. long. Spikes
in a narrow, erect panicle. Lobes of the calyx not keeled. Waste
ground. Naturalized from Europe.
27. AMARAWTHACEAi. Amaranth Family
Mostly herbs, with nearly the characters of the Chenopodia-
ceiv, but with usually 3 dry, translucent, persistent, often
colored, bracts beneath the flower. Most of the genera are
tropical; our commonest species are troublesome weeds, usu-
ally flowering in midsummer or later.
AMARANTHUS L.
Mostly annual herbs. Leaves alternate, simple, thin, usually
entire, often bristle-tipped. Flowers mostly 3-braeted, small,
green or purplish in our wild species, in axillary clusters or
dense terminal spikes. Calyx of 5 or sometimes 3 distinct
erect sepals. Stamens distinct, usually 5, anthers 2-celled.
Styles or stigmas 2 or 3. Fruit small, bladdery, 1-seeded, with
2 or 3 beaks formed by the withered styles.
1.	A. graecizans L. Tumbleweed. Smooth, pale green. Stem
diffusely branched, whitish, the branches slender, ascending. Leaves
small, varying from obovate to spatulate, obtuse or refuse, f-l| in.
long. Flowers greenish, in small axillary clusters, covered by stiff,
sharp-pointed bracts. Sepals 3. In waste ground and a common
field and garden weed. In the autumn the leaves drop and the globu-
lar stem and branches roll freely about before the wind.
2.	A. spinosus L. Spiny Amaranth. Stem stout, ridged, smooth,
busby-branched, often red, 1-4 ft. high. Leaves varying from ovate
to lanceolate, tapering to both ends, dull green, |-3 in. long, each
with a pair of stiff spines in its axil. Flower clusters of two sorts,POKEWEED FAMILY
75
the upper ones of staminate flowers in long slender spikes, the axil-
lary ones globular, composed of pistillate flowers. Bracts lance-awl-
G
Fig. 16. Prince’s feather (Amaranthus hypochondriacus)
A, staminate flower; B, pistillate flower; C, frnit. (All magnified.)
(After Schnizlein)
shaped about the length of the 5 sepals. In waste ground, fields, and
gardens. Naturalized front tropical America.
A. retroflexus I,, and A. hybridus L., usually known as pigweed,
are common autumn-flowering weeds.
28. PHYTOLACCACEAt. Pokeweed Family
Plants with alternate entire leaves. Flowers bisexual, 5-
parted, with the characters of the Goosefoot Family, but the
ovary generally consisting of several carpels, which unite to
form a berry.
PHYTOLACCA L.
Perennial herbs. Stems tall, branching. Leaves large,
entire. Flowers small, in terminal racemes, pedicels bracted.
Calyx of 4—5 nearly equal, persistent sepals. Stamens 5-15,
inserted at the base of the calyx. Styles 5-12, recurved at
the apex. Fruit a depressed-globose, juicy berry.*
1. P. decandra L. Pokeweed. Stems erect, smooth, branched
above, usually dark purple, 4-7 ft. tall ; root large, fleshy, poisonous.
Leaves ovate-lanceolate, smooth, acute, long-petioled. Racemes pe-
duneled, manv-flowered, opposite the leaves; flowers white, becoming
purplish. Stamens 10, shorter than the sepals. Styles 10, carpels 10.76
KEY AND FLORA
Fruit a dark purple berry. A weed on waste ground. The young
branches are often eaten like asparagus, and the root, known as
“ garget root,” is used in medicine.*
29. AIZOACEA£. Ice Plant Family
Mostly fleshy plants, mainly natives of Africa. Flowers
often large and showy. Stamens often doubled and some of
them petal-like. Ovary 2-niany-celled.
[Our only very common genus belongs to a subfamily which
has little resemblance to the fleshy “ ice plants,” found in some
gardens, which best represent the family as a whole.]
MOLLUGO L.
Low branching annuals. Sepals 5, greenish outside, white
inside. Corolla wanting. Stamens 5, alternate with the
sepals, or 3, alternate with the cells of the ovary. Capsule
3-celled, many-seeded.
1. M. verticillata L. Carpet Weed. Stems branching and form-
ing radiating patches. Leaves clustered in apparent whorls at the
joints of the stem, spatulate. Flowers in little sessile umbels at the
joints. Stamens commonly 3. A troublesome weed in sandy soil and
common on sandy beaches and river banks.
30. PORTULACACEZE. Purslane Family
Generally herbs. Leaves ojiposite or alternate, entire;
stipules dry and membranaceous. Sepals 2. Petals 4 or more,
distinct or united below. Stamens 4 or more, liypogynous or
perigynous. Ovary usually superior, 1-celled ; style simple or
3-cleft ; ovules 2-many. Capsule opening transversely with a
lid, or 2-8-valved.
I. CLAYTONIA L.
Perennial. Stem simple, smooth, erect, 4-10 in. high.
Leaves 2, opposite, smooth, succulent. Flowers in a terminal
raceme. Sepals 2, ovate, persistent. Petals 5, sometimes
joined at the base. Stamens 5, somewhat perigynous. Style
3-cleft; ovary 1-celled, 3-6-seeded.PINK FAMILY
77
1.	C. virginica L. Spring Beauty. Stem simple, erect from a deep,
tuberous root. The 2 stem leaves narrowly elliptical, 3-6 in. long,
smooth, fleshy; basal leaves occasionally produced. Flowers on short
pedicels. Petals white or pink, with darker veins, §-§ in. long, notched.
Capsules shorter than the persistent sepals. Common in rich woods.*
2.	C. caroliniana Michx. Northern Spring Beauty. Flowers
fewer, smaller, and whiter than in No. 1, fragrant. Leaves 1-2 in.
long, ovate-lanceolate or spatulate, rather distinctly petioled. Moist
woods, especially N.
n. PORTULACA L.
Annual. Stems low, diffuse, and spreading, fleshy. Leaves
entire, mostly alternate. Flowers terminal, perigynous. Sepals
2, united at the base. Petals usually 5, quickly withering.
Stamens 8-20. Style 3-8-parted. Capsules globose, opening by
the upper portion coming off like a lid, 1-celled, many-seeded.*
1.	P. oleracea L. Purslane. Stems prostrate, diffuse, fleshy.
Leaves alternate, flat, obovate or wedge-shaped. Flowers solitary,
sessile, opening in bright sunshine in the morning and usually
withering before noon. Sepals broad, acute. Petals yellow. Sta-
mens 10-12. Capsule very many-seeded, seeds small, wrinkled. A
common garden weed.*
2.	P. grandiflora Hook. Garden Portulaca. Stems fleshy, erect
or ascending, densely hairy or nearly smooth, 3-G in. long. Leaves
alternate, cylindrical, fleshy, £-1 in. long. Flowers 1-2 in. wide,
white, yellow, or red, showy, opening only in sunlight. Common in
cultivation and often growing spontaneously.*
31. CARY0PHYLLACE2E. Pink Family
Herbs sometimes woody below, with thickened nodes.
Leaves opposite, entire ; stipules small and dry or none.
Sepals 4-5. Petals 4—5 (rarely 0), usually liypogynous. Sta-
mens usually 8-10, hypogynous or perigynous. Styles 2-5
(rarely 1). Ovules 1-mariy. Fruit usually a capsule.
A
Sepals distinct or nearly so. Petals (if any') without claws. Capsules
several-many-seeded.
Styles usually 8. Capsule ovoid.	Stellaria, I
Styles 5 or 4- Capsule cylindrical.	Cerastium, II78
KEY AND FLORA
B
Sepals more or less united. Petals with claws. Capsule several-
man y-seetled.
(a)	Calyx without bracts, its lobes long and leaf-like.
Agrostemma, III
(b)	Calyx without bracts, lobes not leaf-like. Styles 3 or 4.
Silene, V
(c)	Calyx without bracts, lobes not leaf-like. Styles 5 (rarely I).
Lychnis, IV
(d)	Calyx with little bracts at the base. Styles 2.
Dianthus, VI
I. STELLARIA L. (ALSINE)
Slender, usually smooth herbs. Flowers small, white, soli-
tary, or in forking cymes. Sepals 5 (rarely 4). Petals 5
(rarely 4), 2-cleft or -divided. Stamens 10 (rarely 8, 5, or 3),
maturing in 2 sets. Styles 3 (rarely 4 or 5), opposite the same
number of petals ; ovary 1-celled, many-ovuled. Capsule short,
splitting into as many valves as there are styles.
1.	S. longifolia Muhl. Long-Leaved Stitchwort. Stem slender,
usually erect, 8-13 in. high, often sharply 4-angled. Leaves linear
or nearly so, spreading. Flower clusters peduncled, many-flowered,
the pedicels spreading. Petals 2-parted, at length longer than the
calyx. Perennial in meadows and grassy thickets, especially N.
2.	S. graminea L. Smooth, weak, ascending. Stem sharply
4-angled, 12-20 in. long. Leaves linear-lanceolate or broader,
widest a little above the base, ciliate, acute, f-l| in. long. Cyme
loose, with slender, widely spreading pedicels. Flowers in. in
diameter. Sepals and petals about equal in length, the petals cleft
almost to the base. Seeds with many minute tubercles. Fields and
roadsides, often among grass. Naturalized from Europe.
3.	S. media Cyrill. Common Chickweed. Stem prostrate, 6-18
in. long, with a line or two of hairs along it. Leaves ovate, taper-
pointed, the lower petioled, the upper sessile. Petals shorter than the
sepals, sometimes wanting. An annual weed, naturalized from Europe,
common in damp, shady places N.
II. CERASTIUM L.
Annual or perennial. Stems diffuse, usually downy ; leaves
opposite. Flowers white, peduncled, in terminal, regularlyPIXK FAMILY
79
forking cymes. Sepals 4-5. Petals 4-5, notched or 2-cleft.
Stamens 10. Styles 5 or less. Capsules cylindrical, 1-celled,
many-seeded.*
1.	C. arvense L. Field Chickweed. Perennial. Stems tufted,
erect or ascending, 4-10 in. high. Basal leaves and those of flower-
less branches linear-oblong, crowded; those of flowering stems linear
or lance-linear. Flowers $-f in. in diameter, in cymes. Petals obeor-
date, much longer than the sepals. Pods hardly longer than the
calyx. In dry or rocky soil.
2.	C. vulgatum L. Mocse-Ear Chickweed. Annual or some-
times perennial. Stems diffuse, tufted, clammy-downy, 6-12 in.
high. Lower leaves spatulate, the upper oblong, acute, or obtuse ;
bracts thin and dry. Flowers in loose cymes, pedicels becoming
much longer than the calyx. Sepals lanceolate, acute, about as long
as the 2-cleft petals. Slender capsule becoming twice as long as the
calyx and curved upward. A common garden weed.*
3.	C. brachypodum Robinson. Annual. Stems 3-10 in. high,
clammy-downy. Lower leaves oblanceolate or spatulate, the upper
ones linear to lanceolate. Pedicels shorter or not much longer than
the calyx. Petals longer than the sepals. Capsule straight or slightly
curved upwards. In dry soil.
HI. AGROSTEMMA L.
Annual. Stem pubescent,-branching above. Leaves linear-
lanceolate or linear, pubescent, sessile. Flowers showy, on
long and naked peduncles in terminal corymbs. Calyx tubu-
lar, the tube oblong, 10-ribbed; lobes elongated, leaf-like,
deciduous. Petals 5, shorter than the calyx lobes, entire.
Stamens 10. Styles 5, capsules 1-celled.*
1. A. Githago L. Corn Cockle. Stem erect, rather slender, 1-3
ft. tall, gray, with long, appressed hairs. Leaves linear-lanceolate,
acuminate, erect, 2-4 in. long. Petals obovate, notched, purple.
Capsule 5-toothed, many-seeded; seeds black. An introduced weed,
common in grain fields.*
IV. LYCHNIS L.
Plants with nearly the same characteristics as Silene, but
usually with 5 styles.
1. L. Coronaria Desr. Mfc'LLFUx Pink. A forking perennial plant,
2 ft. high, covered with white, cottony dow7n. Leaves very wavy,80
KEY AND FLORA
spatulate; stem leaves ovate-lanceolate, wavy, clasping. Peduncles
long, 1-flowered. Flowers about 1^- in. broad, deep crimson. Calyx
tube very strongly o-ribbed, with 5 smaller ones between; calyx
teeth short and slender. Petals somewhat notched. Cultivated in
old gardens; from Europe.
2.	L. chalcedonies L. Scarlet Lychnis, London Pride. A tall,
hairy perennial (about 2 ft.). Leaves lance-ovate, somewhat clasping.
Flower cluster flat-topped and very dense. Flowers bright scarlet,
not very large. Petals 2-lobed. Common in old gardens; from
Japan.
3.	L. Drummondii Wats. Perennial, erect, glandular-downy and
sticky, 1-3 ft. high. Leaves oblanceolate or linear, acute, j-3 in.
long. Flowers few, on slender pedicels, white or purplish, -f-f in. long.
Petals not much longer than the tubular calyx. Capsule 1—| in. long.
Seeds with little tubercles. In dry soil W.
V. SILENE L.
Annual or perennial herbs. Stems erect or decumbent and
diffuse. Leaves often connate or whorled. Flowers clustered
or solitary, usually pink or white. Calyx tubular, more or
less inflated, 5-toothed, 10-nerved, bractless. Petals 5, long-
clawed, and with the ten stamens inserted at the base of the
ovary. Styles 3; ovary 1-eelled or 3-celled at the base, open-
ing by 6 teeth, many-seeded. Seeds usually roughened.*
1.	S. antirrhina L. Sleepy Catciifly. Stem smooth, slender,
8-30 in. high, sticky in spots. Leaves lanceolate or linear. Flowers
rather few and small, panicled. Calyx ovoid. Petals inversely heart-
shaped, piuk, opening only for a short time in sunshine. Dry waste
ground.
2.	S. Armeria L. Catciifly, None-so-Pretty. A smooth, erect
annual or biennial, 6-15 in. high. Several nodes of the stem are
usually covered for part of their length with a sticky substance.
Leaves very smooth, with a bloom beneath, lanceolate or oblong-
lanceolate, clasping. Flowers showy, dark pink, nearly J in. in
diameter, in flat-topped clusters. Calyx club-shaped. Petals some-
what notched. Cultivated from Europe and introduced.
3.	S. noctiflora L. Night-Flowering Catciifly. A tall, coarse
annual or biennial weed, covered with sticky hairs. Lower leaves
spatulate, upper ones lanceolate, pointed. Flowers large, -white, open-
ing' at night or in cloudy weather. Calyx teeth long, awl-shaped.
Petals 2-parted. In fields and gardens. Naturalized from Europe.FINK FAMILY
81
4.	S. pennsylvanica Michx. Wild Pink. A perennial with low,
clustered stems (4-8 in.). Basal leaves wedge-shaped or spatulate,
those of the stem lanceolate. Flowers medium-sized, clustered.
Petals wedge-shaped, notched, pink, with a crown at the throat of
the corolla. Gravelly soil E.
5.	S. virginica L. Fire Pink. A slender perennial, with erect
stem, 1-2 ft. high. Basal leaves spatulate, the upper leaves oblong-
lanceolate. Flowers few, peduncled, large and showy, bright crimson.
Corolla crowned, petals deeply 2-cleft. Woods.
6.	S. latifolia Britten and Rendle. Snappers, Rattle box. A
perennial branched herb about 1 ft. high. Leaves opposite, smooth,
ovate or ovate-lanceolate. Calyx thin and bladdery, beautifully
veined. Petals white, 2-cleft. Capsule nearly globular. In fields and
along roadsides, especially eastward. Naturalized from Europe.
VI. DIANTHUS L.
Tufted, mostly perennial herbs, often shrubby at the base.
Leaves narrow and grass-like. Flowers solitary or variously
clustered. Calyx tubular, 5-tootlied, witli overlapping bracts
at the base. Petals 5, with long claws. Stamens 10, maturing
5 at a time. Styles 2; ovary 1-celled. Capsule cylindrical,
4-valved at the top.
1.	D. barbatus L. Sweet William. Perennial, often in large
clumps. Stems erect, branching above, smooth, 1-2 ft. tall. Leaves
lanceolate, 2-3 in. long, acute. Flowers crimson-pink, white or
variegated, in terminal clusters; bracts linear, as long as the calyx.
Common about old gardens; from Europe.*
2.	D. Armeria L. Deptford Pink. Rather erect, annual, with
stiff stems 1-2 ft. high. Leaves very dark green, linear, 1-2 in. long,
the lower obtuse, the upper acute. Flowers loosely clustered, small,
dark pink. Calyx tube J—| in. long, nearly cylindrical. Petals nar-
row, speckled with very small whitish dots. In sandy fields eastward.
Introduced from Europe ; sometimes cultivated.
3.	D. plumarius L. Common Pink, Grass Pink. Leaves grass-
like, with a whitish bloom. Petals white, pink, or variegated, with
the limb fringed. Flowers solitary, fragrant. Hardy perennials,
cultivated from Europe.
4.	D. Caryophyllus L. Carnation, Clove Pink. Much like the
preceding species, but with larger fragrant flowers; the broad petals
merely crenate. Hothouse perennials (some hardy varieties), culti-
vated from Europe.82
KEY AND FLORA
32. NYMPH.3LACE2E. Water Lily Family
Perennial aquatic herbs. Leaves usually floating, often shield-
shaped. Flowers borne on naked scapes. Floral envelopes and
stamens all hypogynous or epigynous. Sepals 3-6. Petals
3-5 or often very numerous. Stamens many. Carpels 3 or
more, free or united. Fruit a berry or a group of separate
carpels.
I. NYMPH^A L.
Eootstock horizontal, thick, cylindrical. Leaves heart-shaped,
floating or erect. Flowers yellow. Sepals 4-6, green on the
outside, obovate, concave. Petals many, hypogynous, the
inner ones becoming small and stamen-like. Stamens many,
hypogynous. Ovary cylindrical, many-celled; stigma disk-
shaped. Fruit ovoid.*
1. N. advena Ait. Yellow Pond Lily, Cow Lily, Spatter-
Dock. Leaves oval or orbicular, rather thick, often downy beneath.
Flowers brig lit yellow, 2-3 in. in diameter, depressed-globular.
Sepals <i. Petals thick and fleshy, truncate. Stamens in several
rows; anthers nearly as long as the filaments. In slow streams and
still water.*
II. CASTALIA Salisb.
Eootstock horizontal, creeping extensively. Leaves float-
ing, entire) shield-shaped or heart-shaped. Flowers showy.
Sepals 4, green without, white within. Petals many, white,
becoming smaller towards the center. Stamens many, the
outer with broad and the inner with linear filaments. Ovary
many-celled, stigmas shield-shaped and radiating. Fruit berry-
like, many-seeded.*
1.	C. odorata Woodville and Wood. White Water Lily. Root-
stock large, branched but little. Leaves floating, entire, the notch
narrow and basal lobes acute, green and smooth above, purple and
downy beneath. Petioles and peduncles slender. Flowers white, very
fragrant, opening in the morning, 3-5 in. broad. Fruit globose; seeds
inclosed in a membranaceous sac. In ponds and still water.*
2.	C. tuberosa Greene. Much like No. 1. Rootstock bearing loosely
attached, often compound tubers. Leaves round-kidney-shaped, sel-
dom purple beneath. Flowers larger than in No. 1, scentless or nearly
so. Slow streams, especially IV.BUTTERCUP FAMILY
83
ID. KELUMBO Adans.
Rootstock large and stout. Leaves round, shield-shaped,
often raised above the water. Flowers large, raised above water
at first, but often submerged after blooming. Sepals and petals
hypogynous, numerous, the inner sepals and outer petals not
distinguishable from each other. Stamens many, hypogynous.
Pistils several, 1-ovuled, borne in pits in the flattish upper sur-
face of a top-shaped receptacle, which enlarges greatly in fruit.
1. W. luteaPers. American Lotus, Water Chinquapin. Root-
stock often 3-4 in. in diameter, horizontal. Leaves 11-21 ft. broad,
prominently ribbed, with much bloom above, often downy beneath.
Petioles and peduncles stout. Flowers pale yellow, 5-9 in. broad.
Sepals and petals falling quickly. Fruit top-shaped, 3-4 in. in diam-
eter ; the seeds § in. in diameter. In ponds and slow-running streams
W., introduced from the Southwest.*
33. RANUNCULACEiE. Buttercup Fajiily
Herbs, rarely shrubs, usually with biting or bitter juice.
Leaves basal or alternate (in Clematis opposite; stem leaves
or involucre whorled in Anemone); stipules none or adnate
to the petiole. Floral organs all distinct and unconnected.
Sepals 0 or more (rarely 2-4), falling early, often petal-like.
Petals none, or 5 or more (rarely 3). Stamens many. Carpels
many, 1-celled ; stigmas simple; ovules 1 or more. Fruit com-
posed of 1-seeded akenes or many-seeded follicles. Seeds small.
A
Flowers zygomorpldc.
With a spur.	Delphinium, XII
With a hood.	Aconitum, XIII
B
Flowers actinomorpliic.
1. Petals present (in (c) not very unlike the stamens).
(a) Petals very large and showy.	Paeonia, IX
(i) Petals small, tubular at the tip.	Coptis, X
(c)	Petals narrow, spatulate, on slender claws. Aetsea, XIV
(d)	Petals prolonged backward into spurs.	Aquilegia, XI
(e)	Petals flat, with a little scale at the base, inside. Ranunculus, I84
ESSENTIALS OF BOTANY
Cut a thin section at right angles to the skin and examine with
a high power. Moisten the section with iodine solution and exam-
ine again.
If possible, secure a potato which has been sprouting in a warm
place for a month or more (the longer the better), and look near the
origins of the sprouts for evidences of the loss of material from the
tuber.
EXPERIMENT XII
Use of the Corky Layer. — Carefully weigh a potato, then pare
another larger one, and cut portions from it until its rveight is made
approximately equal to that of the first one. Expose both freely to
the air for some days and reweigh. What does the result show in
regard to the use of the corky layer of the skin?
99.	Morphology of the Potato. — It is evident that in the
potato we have to do with a very greatly modified form of
stern. The corky layer of the bark is well represented, and
the loose cellular layer beneath is very greatly developed;
wood is almost lacking, being present only in the very narrow
ring which was stained by the red ink, but the pith is greatly
developed and constitutes the principal bulk of the tuber.
All this is readily understood if we consider that the tuber,
buried in and supported by the earth, does not need the
kinds of tissue which give strength, but only those which
are well adapted to store the requisite amount of food.
100.	Structure of a Bulb; the Onion. — Examine the external
appearance of the onion and observe the thin membranaceous skin
which covers it. This skin consists of the broad sheathing bases of
the outer leaves which grew on the onion plant during the summer.
Remove these and notice the thick scales (also formed from bases of
leaves as shown in Fig. 3.">) which make up the substance of the bulb.
Make a transverse section of the onion at about the middle and
sketch the rings of which it is composed. Cut a thin section from
the interior of the bulb, examine with a moderate power of the.
microscope, and note the thin-walled cells of which it is composed.WORK OF THE STEM
85
Split another onion from top to bottom and try to find :
(a)	The plate or broad flattened stem inside at the base (Fig. 34).
(b)	The central bud.
(c)	The bulb-scales.
(d)	In some onions (particularly large, irregular ones) the bulblets
or side buds arising in the axes of the scales near the base.
Test the cut surface for starch.
101.	Plant-Foods in the Onion. -— Grrape sugar is an impor-
tant substance among those stored for food by the plant.
It received its namd from the fact that it was formerly
obtained for chemical examination from grapes. Old, dry
raisins usually show little masses of whitish material
scattered over the skin-which are nearly pure grape sugar.
Commercially it is now manufactured on an enormous
scale from starch by boiling with diluted hydrochloric acid.
In the plant it is made from starch by processes as yet
imperfectly understood, and another sugar, called.maltose,
is made from starch in the seed during germination.
It may be readily shown by suitable experiments that
the onion contains both grape sugar and proteids.
102.	Tabular Review of Experiments. — [Continue the table from
Sect. 38.]
103.	Review Summary of Work of Stem.
fin young dicotyledonous stems.
Channels for upward movement J in dicotyledonous stems several
of water....................j years old.
[ in monocotyledonous stems.
Channels for downward move- ( in dicotyledonous stems.
ment of water...............\ in monocotyledonous stems.
Channels for transverse move-
ments.
r where stored.
Storage of plant-food .	.	.	. < kinds stored.
I, uses.86
KEY AND FLORA
1.	T. dioicum L. Early Meadow Rue. Plant 1-2 ft. high,
smooth and pale or with a bloom. Leaves all petioled, most of them
thrice compound in threes; leaflets thin and delicate, roundish, 3-7-
lobed. Flowers in slender panicles, purplish or greenish ; stand sate
ones with slender, thread-like filaments, from which hang the con-
spicuous yellowish anthers. Rocky woods and hillsides.
2.	T. polygamum Muhl. Tall Meadow Run. Stems from fibrous
roots, tall and coarse, nearly or quite smooth, 4-8 ft. tall. Leaves
twice compound, those of the stem sessile, the others long-petioled;
leaflets oval or oblong, often cordate, smooth or downy beneath,
quite variable in size on the same plant. Flowers small, in large
panicles. Sepals 4 or 5, white. Filaments club-shaped. Akenes
short-stalked. Thickets and meadows E.
III. ANEMONELLA Spaeli. (SYNDESMON)
Small, perennial herbs. Leaves compound, smooth, the
basal ones long-petioled, those of the stem sessile. Flowers
in a terminal umbel, slender-pedieeled. Sepals petal-like.
Petals none. Pistils 4-15 ; stigmas sessile, truncate.*
1. A. thalictroides Spach. Rue Anemone. Stem slender, 6-10 in.
high, from a cluster of tuberous roots. Basal leaves long-petioled,
twice compound in threes; leaflets oval, heart-shaped, 3-5-lobed.
Stem leaves 2-3 compound in threes, wliorled, the long-stalked leaf-
lets veiny, forming an involucre of 6-9 apparently simple leaves.
Flowers 3-6 in an umbel, |-J in. wide; sepals 6-10, white. In rich
woods.*
IV. HEPATICA Hill
Involucre of 3 small, simple leaves, so close to the flower as
to look like a catyx. Leaves all basal, 3-lobed, heart-shaped,
thick, and evergreen, purplish-red beneath. Flowers single,
on rather slender hairy scapes.
1.	H. triloba C'liaix. Round-Loised Hepatic a. Lobes of the
leaves obtuse or rounded; those of the involucre obtuse; sepals
6-12, varying from blue to white.
2.	H. acutiloba DC. Siiai: i -Lobed Hkpatic.v. Closely similar to
the former, except for the acute lobes of the leaves and tips of the
involucre.
[Both species have many local names, such as Liverleaf, Liverwort,
Noble Liverwort, .Spring Beauty.]BUTTERCUP FAMILY
87
V. ANEMONE L.
Perennial herbs, usually with basal leaves, and 2 or 3 op-
posite or whorled stem leaves, constituting an involucre some
distance below the flower or flower cluster. Sepals few or nu-
merous, colored and petal-like. Petals usually wanting. Akenes
pointed, or with long, feathery tails.
1.	A. patens L., var. Wolfgangiana. Pasque Flower. Low plants,
1	in.-l ft. high, clothed with long, silky hairs. Leaves divided
in threes. Flower single, large, showy, pale-purplish, borne on a
peduncle developed before the leaves. Carpels many, with long,
hairy styles, which in fruit form tails 2 in. long. Prairies and
bluffs, X.W.
2.	A. caroliniana Walt. Carolina Anemone. Stem simple, from
a roundish tuber, slightly downv, (3-12 in. high, bearing a single
flower about 1 in. broad. Basal leaves 2-3, long-petioled, compound
in threes, the divisions cut or lobed; stem leaves sessile, compound
in threes, the divisions wedge-shaped. Sepals 12-20, white; head of
fruit becoming oblong; akenes woolly. In open woods W.*
3.	A. cylindrica Gray. Long-Fruited Anemone. Plants about
2	ft. high, branching, with an involucre of long-petioled, divided, and
cleft leaves, from within which spring several long, naked peduncles.
Flowers greenish-white. Sepals obtuse. Head of fruit cylindrical,
composed of very many densely woolly akenes. Dry woods and
prairies.
4.	A. virginiana L. Plant hairy, 2-3 ft. high. Peduncles 6-12 in.
long, sometimes forking, the first ones naked, the later ones with a
little 2-leaved involucre at the middle. Leaves of the involucre 3.
each 3-parted, the divisions ovate-lanceolate, pointed. Sepals acute.
Head of fruit ovoid. Woods and meadows.
5.	A. canadensis L. Plant hairy, rather low. Peduncle arising
from a 3-leaved primary involucre, then branching, each branch
bearing at the middle a 2-leaved secondary involucre. Leaves of the
primary involucre broadly wedge-shaped, 3-cleft, the divisions cut
and toothed. Sepals obovate, white. Head of fruit spherical. In
low ground or woods.
6.	A. quinquefolia L. Wind Flower, Wood Anemone. Stem
simple, from a thread-like rootstock; involucre of 3 leaves, each
petioled, and of 3 leaflets, which are cut, toothed, or parted. Pedun-
cle 1-flowered. Sepals 4-7, white, often tinged with purple outside.
Carpels 15 or 20. This species is very nearly related to, but now
regarded as distinct from, the European .1. nemorosa.88
KEY AND FLORA
VI.	CLEMATIS L.
Perennial herbs or slightly woody vines, usually climbing
by the leafstalks. Leaves opposite, simple or compound.
Sepals 4, petal-like. Petals very small or wanting. Pistils
numerous, tipped by the persistent styles, which often become
long and plumose in fruit.*	*
1.	C. crispa L. Marsh Clematis, Stem climbing, a little woody
below, slightly downy above, 3-5 ft. high. Leaves pinnately com-
pound ; leaflets 5-7, varying from lanceolate to ovate, thin, entire
or 3-5-lobed. Flowers showy, perfect, solitary, on long axillary pedun-
cles. Sepals lanceolate, taper-pointed, thick, wavy on the margins,
twice the length of the stamens, light bluish-purple, 1-1| in. in length.
Tails of the ripened akenes 1 in. long, silky. Rich woods and river
banks S.*
2.	C. ViornaL. Leather Flower. Stem climbing, nearly smooth,
0-10 ft. long. Leaves usually pinnately compound, the lowest pair
often compound in threes and the upper pair simple. Leaflets usu-
ally 5-7, oblongnovate or oval, acute, firm, entire or lobed. Calyx
beil-shaped, nodding; sepals ovate, taper-pointed with a short, re-
curved point, thick and leathery, reddish-purple, 1 in. long. Tails
of the akenes plumose, 11 in. long, brownish. On river banks and
rich soil.*
VII.	ISOPYRUM L.
Small, smooth herbs. Leaves 2-3 times compound, in
threes; the leaflets 2-3-lobed. Flowers peduncled, white.
Sepals 5, petal-like, soon falling. Petals wanting (in our
species). Stamens 1CMD. Pistils 3-6 or more.
1. I. biternatum T. & G. A delicate, erect plant, with alternate
branches, looking much like Anemonella, with clustered stems from
perennial tuberous roots. Damp woods.
VIII.	CALTHA I,.
Smooth perennials with large, roundish leaves. Sepals
petal-like, 5-9. Petals none. Pistils 5-10, each consisting
of a 1-celled ovary with a nearly sessile stigma. Fruit a
many-seeded follicle.
1. C. palustris L. Marsh Marigold, Cowslips, Meadow But-
tercup (both the latter unsuitable names, but in common use). Stem
hollow, smooth, ascending ; leaves smooth, roundish and hearbshaped,BUTTERCUP TAMILT
89
or kidney-shaped, ■with crenate, dentate, or nearly entire margins;
the broad oval sepals bright yellow. Swamps or wet ground.
IX. PiEONIA L.
Perennial, from thick, fleshy roots ; stems shrubby or her-
baceous. Leaves much divided. Flowers terminal, large and
showy. Sepals 5, leaf-like and persistent. Petals 5 or more.
Pistils 3-5; ovaries surrounded by a disk.*
1. P. officinalis L. Garden7 Peony. Herbaceous; flowering stems
1-2 ft. high. Leaves ample; leaflets lance-ovate, cut or incised, smooth.
Flowers double, white or red. Follicles 2, erect, many-seeded. Com-
mon in gardens.*
X.	COPTIS Salisb.
Low, smooth perennials, with 3-divided basal leaves. Flowers
small, white, on scapes. Sepals 5-7, petal-like, soon falling.
Petals 5-7, small, club-shaped, tubular at the apex. Stamens
15-25. Pistils 3-7, stalked. Pods thin and dry, 4-S-seeded.
1. C. trifolia Salisb. Gold Thread. A pretty, delicate plant,
with slender, 1-flowered scapes, from long, bright-yellow, thread-
like rootstocks, which are bitter and somewhat medicinal. Leaves
later than the flowers, each of 3 w'edge-shaped leaflets, which finally
become shining and evergeen. Damp, cold woods and bogs.
XI.	AQUTLEGIA L.
Perennials, with leaves twice or thrice palmately compound,
the divisions in threes.
Sepals 5, petal-like, all similar. Petals 5, all similar, each
consisting of an expanded portion, prolonged backward into a
hollow spur, the whole much longer than the calyx. Pistils 5,
forming many-seeded pods.
1.	A. canadensis L. Wild Columbine. Flowers scarlet without,
yellow within, nodding; spurs rather long.
2.	A. vulgaris L. Garden Columbine. Flowers often double, and
white, blue, or purple. Spurs shorter and more hooked. Cultivated
from Europe, and sometimes become wild.
xn. DELPHINIUM L.
Annual or perennial herbs. Stem erect, simple or branched.
Leaves alternate, petioled, palmately divided. Flowers in90
KEY AYD FLORA
terminal racemes or panicles, showy. Sepals 5, colored, irregu-
lar, the upper one prolonged into a spur. Petals 4, unequal,
the two upper ones with long spurs which are inclosed in the
spur of the upper sepal, the other two short-stalked. Pistils
1-5; ovaries many-seeded.*
1.	D. tricorne Michx. Dwarf Larkspur. Perennial. Stem simple,
from a tuberous root, usually low (j—1 ft. high), but sometimes
2 ft. high. Leaves deeply 5-parted, the divisions irregularly 3-5-cleft.
Racemes few-flowered, loose. Flowers blue, sometimes white. Pods
diverging. Southward.
2.	D. azureum Michx. Blue Larkspur. Perennial. Stem usually
simple, slender, downy, 1-2 ft. high. Leaves 2-3 in. wide, 3-5-parted,
the divisions cleft into 3-5 narrow, toothed, or entire lobes. Flowers
in a strict, many-flowered, terminal raceme, showy, blue or whitish.
Spur ascending, curved; lower petals bearded, 2-cleft. Pods erect.
On rich or rocky soil in open places, N.*
XIII. ACONITUM L.
Erect, perennial herbs. Leaves alternate, palmately lobed
or cut. Flowers irregular, in panicles or racemes. Sepals 5,
the back one large, arched, and hooded, the front one the
narrower. Petals 2-5, small, the 2 back ones clawed and
covered by the hood of the sepals ; 3 lateral ones small or
wanting. Follicles 3-5. Seeds many, wrinkled.
1. A. Napellus L. Monkshood. An erect, poisonous plant, 1-2 ft.
high. Raceme simple and densely flowered. Flowers dark blue. Cul-
tivated from Europe.
Several native species of AconMum occur within our limits, but
they are not common.
XIV. ACTASA L.
Perennial. Stem simple. Leaves 2-3, compound in threes;
leaflets ovate, sharply cut or toothed. Flowers white, in a
short and thick terminal raceme. Sepals 4-5, soon deciduous.
Petals 4-10, small. Pistil single; stigma 2-lobed. Fruit a
many-seeded berry.*
1. A. rubra Willd. Red Bane be rev. Stem about 2 ft. high.
Raceme ovoid or hemispherical. Petals acute. Pedicels slender.
Berries usually red, sometimes white, ovoid. Common N.BARBERRY FAMILY
91
2. A. alba Miller. Banf.bkhiiv, Stem erect, smooth or nearly so,
18-54 in. high. Leaves large and spreading; leaflets thin. Racemes
very broad. Petals slender, truncate. Pedicels red, thickened in
fruiting; berries white. In rich woods, more common S.*
34. BERBERIDACEAI. Barberry Family
Herbs or shrubs. Leaves alternate, simple or compound,
usually without stipules. Sepals petal-like. Petals hypogy-
nous, distinct, their number some multiple of 2, 3, or 4, never
of 5. Stamens usually one opposite each petal; anthers com-
monly opening by 2 uplifted lids (the stamens of Podophyllum
are exceptional). Pistil 1, 1-celled; ovules 2 or more. Fruit a
berry or capsule.
1. PODOPHYLLUM L.
Perennial. Stem simple, smooth, erect, 12-15 in. tall, bear-
ing 2 leaves with a large white flower between them. Sepals
6, falling off as the flower opens. Petals <1—9. obovate. Sta-
mens twice as many as the petals; anthers splitting open
lengthwise. Pistil 1; stigma large, flat, sessile. Fruit berry-
like, 1-celled, many-seeded.*
1. P. peltatum L. May Apple. Rootstock rather large. Leaves
orbicular, shield-shaped, o-9-lobed and toothed, smooth, 9-15 in.
wide. Flowers 1-2 in. wide, on a peduncle 1-5 in. long. Stamens
prominent; anthers opening longitudinally. Fruit 11-5 in. long,
oval, fragrant, edible ; each seed surrounded by a pulpy covering.
In rich woods. The roots and leaves are used in medicine.*
H. CAULOPHYLLUM Mielix.
A perennial smooth herb, 1-24 ft. high. Leaf large, single,
sessile, thrice compound in threes, borne high up on the stem;
there is also a large, very compound basal leaf. Flowers
racemed or panicled, yellowish-green. Sepals 6, with 3 bract-
lets. Petals 6, gland-like, somewhat curved inward at the tip,
much smaller than the sepals. Pistil 2-ovuled, the ovary soon
bursting open and leaving the 2 blue seeds to ripen naked.
1. C. thalictroides Michx. Blue Cohosh, Patpoose Root. Whole
plant purplish and covered witli a bloom when young. Flowers
appearing before the leaf is fully developed. Rich woods.92
KEY AND FLORA
III. BERBERIS L.
Spiny shrubs with yellow wood. Leaves spinous-toothed,
jointed on the very short petiole, often reduced to 3-7-cleft
spines. Flowers in racemes, solitary or in pairs. Sepals 8-9, the
outer minute. Petals 6, each with 2 nectar glands at the base.
Stamens 6. Ovules few. Berry 1-2-seeded ; seeds bony-coated.
1.	B. vulgaris L. Common Barberry. A shrub 4-6 ft. high.
Leaves obovate, spinous-serrate; those on the old shoots mere
spines. Flowers pale yellow, in drooping racemes. Stamens irritable,
closing quickly toward the center of the flower when touched. Berry
i in. long, nearly ellipsoidal in shape, scarlet or orange-scarlet, very
acid, eatable when cooked. Cultivated from Europe and introduced
in eastern New England and locally in the upper Mississippi Valley.
2.	B. Thunbergii DC. A low shrub. Leaves entire, turning red
and remaining so for a considerable time in autumn. Flowers
solitary or in pairs. Berries bright red, remaining on the branches
all winter. Cultivated from Japan.
35. MAGNOLIACEJE. Magnolia Family
Trees or shrubs. Leaves alternate, not toothed or serrate.
Flowers solitary, large and showy. Floral envelopes and sta-
mens liypogynous. Calyx and corolla colored alike, the parts of
the perianth forming 3 or more circles of 3 parts each. Stamens
many. Carpels many, usually joined over the long receptacle
and forming a sort of cone-shaped fruit, which may be either
fleshy or dry.
I. MAGNOLIA L.
Aromatic trees or shrubs. Leaves alternate, often in clusters
at the ends of the branches, entire, usually thick and leathery ;
stipules large, quickly deciduous. Flowers terminal, showy,
bisexual. Sepals 3, caducous. Petals 6-12, in 2-4 rows, con-
cave. Stamens numerous. Ovaries numerous, 1-celled, 2-seeded,
the mature follicles opening at the beak and the fleshy seeds
remaining for some time suspended by slender threads.*
1. M. virginiana L. Sweet Bay. A small tree with light gray
bark. Leaves scattered on the branches, evergreen, thick and
leathery, oval or oblong, smooth and green above, white and withMAGNOLIA FAMILY
93
a bloom, downy beneath, 4-6 in. long. Flowers white, fragrant, 2—3
in. in diameter; petals 9, concave. Cone 1*—2 in. long, pink. Com-
mon in swamps and along streams, New York and southward (a
few in eastern Massachusetts). The leaves often used in flavoring
soups, etc.
2.	M. acuminata L. Cucumber Tree. A tree 60-90 ft. high.
Leaves thin, oblong or oval, acute, light green and somewhat downy
beneath, 5-10 in. long. Flowers oblong-bell-shaped, greenish-yellow,
2 in. long. Petals much longer than the sepals. Cone of fruit 2-3
in. long, often curved, cylindrical. Woods, especially S.
3.	M. macrophylla Miehx. Large-Leaved Umbrella Tree. A
small tree with gray bark. Leaves clustered at the ends of the
branches, oblong or obovate, obtuse at the apex, cordate at the base,
green and glabrous above, white and downy beneath, 1 -1—3 ft. long;
petioles stout. Flowers white with a purple center, fragrant, 8-12
in. wide. Petals oblong, obtuse, two or three times as long as the
sepals. Cone ovate, 4-6 in. long, bright red at maturity. Shady
woods on light soil S.*
4.	M. Fraseri Walt. Ear-Leaved Umbrella Tree. A small
tree with a slender trunk and widely spreading branches. Leaves
clustered at the ends of the branches, deciduous, oblong or obovate,
contracted, cordate and eared at the base, smooth on both sides,
8-12 in. long; petioles slender. Flowers white and fragrant, 6 in.
broad. Petals longer than the sepals, spatulate or oblong, obtuse at
the apex, narrowed at the base. Cone 3-4 in. long, pink at maturity.
In rich woods S.*
H. LIRIODENDRON L.
A large tree with rough, dark-colored bark. Leaves scat-
tered on the branches, deciduous, 3-lobed, truncate, stipuled,
petioled. Flowers bisexual. Sepals 3, reflexed. Petals 6,
erect. Stamens numerous. Ovaries numerous, 2-ovuled, joined
over each other on the elongated receptacle, never opening,
deciduous.*
1. L. tulipifera L. Tulip Tree. The largest tree in the family.
Leaves roundish in outline, mostly 3-lobed, the terminal lobe trun-
cate or broadly notched, usually heart-shaped at the base, smooth,
green above, lighter beneath; petioles slender. Flowers terminal,
bell-shaped, greenish-yellow marked with orange. Petals obovate,
obtuse, about as long as the sepals. Mature cones ovate, acute, 2-3
in. long. Common on low ground, Pennsylvania and S. Often called
“ white wood,” or, incorrectly, “ white poplar.” Wood valuable for
making boxes and light furniture.*94
KEY AND FLORA
36. CALYCANTHACEAE. Calycanthus Family
Shrubs. Leaves opposite, entire, without stipules. Flowers
solitary, often sweet-scented. Sepals and petals numerous,
the outer sepals bract-like. Stamens many, short, the inner
ones usually sterile. Ovaries' several, inserted on the inside
of an irregular, hollow, pear-shaped receptacle something like
a large rose hip, forming 1-seeded akenes in fruit.
CALYCANTHUS L. (BUTNERIA)
Shrubs, 4-8 ft. tall; branches opposite. Leaves oval, downy
beneath, short-petioled ; both leaves and bark aromatic. Sepals
and petals many, in several rows, somewhat fleshy, indistin-
guishable. Pistils several, inserted on the inner side of the
persistent calyx tube. Mature fruit pear-shaped, dry, inclos-
ing the akenes.*
1. C. floridus L. Sweet-Scented Shrub, Strawberry Bush,
Spice Bush, Shrub. A widespreading bush, 4-8 ft. high; twigs
downy. Leaves oval or oblong, acute or taper-pointed, rough above,
downy beneath, L’-o in. long. Flowers 1 in. wide, brownish-purple, very
fragrant. Sepals united below to form a cup, on the inside of which
the other parts of the flower are inserted ; cup leafy-bracted on the
outside. Banks of streams and rich hillsides S., often cultivated.*
37. ANN ON ACE7E. 1’apaw Family
Trees or shrubs. Leaves alternate, entire, pinnately veined.
Flowers bisexual, hypogynous, axillary, solitary. Calyx of 3
sepals ; corolla of 6 thickish petals in 2 rows. Stamens many ;
filaments very short. Pistils several or many, becoming fleshy
or pulpy in fruit.
ASIMINA Adans.
Shrubs or small trees. Leaves deciduous. Flowers nodding.
Sepals 3, ovate. Petals 6, the 3 outer ones larger and spread-
ing. Stamens very numerous, crowded on the globular recep-
tacle. Ovaries 3-15, sessile, 1-celled, several-ovuled. Fruit a
large, fleshy, oblong berry ; seeds large, horizontal.*LAUREL FAMILY
95
1. A. triloba Dunal. Papa tv. A small tree, 10-20 ft. high;
bark nearly smooth, lead-colored. Leaves oblong-obovate, acute at
the apex, obtuse at the base, rusty-downy when young and becoming
smoother with age, 6-10 in. long. Flowers on branches of the previ-
ous season, appearing before -or with the leaves; the short peduncles
and the sepals brown-downy; petals purple, obovate, 3-4 times
longer than the sepals. Fruit 3-5 in. long, edible when ripe. Com-
mon on banks of streams, especially S. and S.\Y. The bark is very
tough and is often used in the place of rope.*
38. LAURACEZE. Laurel Family
Aromatic plants, nearly always trees or shrubs. Leaves
alternate, simple, usually entire, and marked with translucent
dots. Calyx regular, hypogynous, of 4 or 6 colored sepals.
Stamens in 3 or 4 circles of 3 each, the anthers opening by
valves. Style single. Fruit a 1-seeded berry or drupe.
I.	SASSAFRAS Xees.
A tree with rough, yellowish bark and a spreading top.
Leaves deciduous, entire or 2-3-lobed. Flowers dioecious,
involucrate, at the end of the twigs of the previous season.
Calyx 6-parted, persistent in the pistillate flowers. Stamens
9, in 3 rows. Pistillate flowers writh 4-6 abortive stamens
and a single ovary. Fruit a drupe.*
.	1. S. variifolium Ktze. Sassafras, A tree, usually small and slen-
der, but sometimes with a trunk 3 ft. in diameter and 125 ft. high.
Leaves oval, entire, mitten-shaped or 3-lobed, downy when young lmt
becoming smooth with age, dark green above, paler below, petiolate.
Racemes several in a cluster, peduncled; flowers yellow, .stamens
about as long as tlie sepals. Fruit dark blue, ovoid, on thickened red
pedicels. All parts of the tree aromatic. Trees producing pistillate
flowers rare. Common. The wood Is valuable for cabinet making,
and an aromatic oil is extracted from the bark.*
II.	BENZOIN Fabric.
Shrubs. Leaves deciduous, entire. Flowers in lateral, sessile
clusters, appearing before the leaves, dioecious or somewhat
monoecious. Involucre of 4 scales. Stamens 9 in the staminate96
KEY AXD FLORA
flowers ; filaments slender. Pistillate flowers with 12-15 abor-
tive stamens and a single globose ovary with a short style.*
1. B. sstivale Nees. Spice Bush. A shrub, 5-15 ft. high, with
smooth bark and slender twigs. Leaves oblong-obovate, acute at the
base, pale and downy beneath, becoming smooth when old; petioles
short. Flowers about as long as the pedicels, yellow, very fragrant.
Ovary about as long as the style. Fruit an obovoid, red drupe, about
l in. long, on a slender pedicel. Banks of streams and damp woods.
Twigs and leaves quite aromatic.*
39. PAPAVERACEJE. Poppy Family
Annual or perennial herbs, often with milky juice. Leaves
sometimes all basal; stem leaves usually alternate without
stipules. Flowers bisexual, regular or irregular. Sepals usu-
ally 2, shed as the flower opens. Petals 4-12, falling early.
Stamens numerous or 6 (in 2 sets), 4, or 2. Carpels 2-16.
Fruit a capsule.
I. ESCHSCHOLTZIA Cham.
Annual or perennial herbs. Leaves pale or bluish-green,
usually cut into very narrow divisions. Sepals united into a
pointed cap, which falls off in one piece as the flower opens.
Petals 4, orange or yellow. Stamens many, with long anthers.
Stigmas 2-6, spreading. Pods long and slender, grooved. Re-
ceptacle often surrounded by a rim on which the calyx rests.
1. E. californica Cham. Annual or perennial, with rather succu-
lent leafy stems. Flowers large and showy, yellow or orange-yellow.
Receptacle top-shaped, with a broad rim. Cultivated from California.
II. SANGUINARIA L.
Perennial. Rootstock thick, horizontal; joints and scars
of previous growths persistent several years; juice orange-
colored. Leaves on long petioles, kidney-shaped. Scape 1-
flowered. Sepals 2, falling off as the flower opens. Petals 8-
12. Ovary 1; stigmas 2. Capsule oblong, seeds crested.*
1. S. canadensis L. Bloom root. Leaves and scape with a bloom;
leaves palmately 5-9-lobed, lobes rounded or toothed ; scapes naked,
nearly as long as the petioles. Flowers white, 1 in. or more wide.POPPY FAMILY
97
Petals oblong or obovate, quickly deciduous. Capsule 1-celled, 2-
valved, the valves separating from the persistent placenta; at ma-
turity. In rich, open woods.*
III. -CHELIDONIUM L.
Erect, branched, perennial herbs, with yellow juice. Leaves
much divided. Flowers yellow. Sepals 2, falling as the flower
opens. Petals 4. Ovary 1-celled; style dilated at the top,
with 2 joined stigmas. Capsule linear.
1. C. majus L. Celandine. Stem 1-2 ft. high, brittle, slightly
hairy, leafy. Leaves once or twice pinnate. Flowers small. A rather
common weed in yards and along fences. Naturalized from Europe.
IV. PAPAVER L.
Annual or perennial herbs with milky juice. Stem erect,
smooth, or rough-hairy, branching above. Leaves more or
less lobed or dissected. Flower buds nodding, flowers showy.
Sepals commonly 2, falling off as the flower opens. Petals
4-6. Stamens many. Stigma disk-like; ovules many, borne
on many inwardly projecting placentae.* .
1.	P. somniferum L. Opium Poppy. Annual. Stem erect, branched
above, smooth and with a bloom, 2-3 ft. high. Leaves oblong, irreg-
ularly lobed or cut, sessile, clasping. Flowers nearly white, with a
purple center, large and showy, on long peduncles. Capsule globose,
seeds minutely pitted. About old gardens and waste places. Culti-
vated in southern Asia, where the juice of the capsules is dried to
make opium.*
2.	P. Rhoeas L. Corn Poppy. Annual. Stem erect, hairy, 1-3 ft.
high. Lower leaves petioJed, upper ones sessile, all pinnately cut,
the lobes serrate. Corolla scarlet, often with a dark center, 2-4 in.
in diameter. Capsule smooth, obovoid. "Waste ground, sometimes
in fields. Introduced from Europe and often cultivated.
3.	P. dubium L. Smooth-Fruited Poppy. Annual. Stem slender,
branching, 1-2 ft. tall. Leaves pinnatifid, the lower petioled, the
upper sessile. Flowers large and showy, usually red ; capsule long-
ohovoid, smooth. In cultivated ground. Both this and No. 1 are
often cultivated in gardens and produce double flowers.*
4.	P. orientale L. Oriental Poppy. A large, rough-hairy peren-
nial. Leaves large, deep green, almost pinnate. Flower very large,
deep red. Cultivated from the eastern Mediterranean region.98
KEY AND FLORA
5. P. nudicaule L. Iceland Poppy. A delicate but rough-hairy
perennial plant. Leaves all basal, pale, pinnately cut. Flowers yellow-
orange or white, borne singly on rather slender, hairy scapes. Culti-
vated from Europe.
V. ADLUMIA Raf.
A delicate climbing biennial. Leaves thrice-pinnate, cut-
lobed. Sepals 2, very small. Petals 4, all united into a corolla
which is slightly heart-shaped or 2-knobbed at the base, re-
maining as a spongy covering over the small, few-seeded pod.
1. A. fungosa Greene. Mountain Fringe, Allegheny Vine.
Climbing several feet high by the leafstalks. Flowers pinkish-
white. Rocky hillsides, often cultivated.
VI. DICENTRA Bernk. (BICUCULLA)
Smooth, delicate herbs, with watery juice. Leaves compound
in threes and finely cut. Flowers racemed, nodding. Sepals 2,
small and scale-like. Petals 4, slightly united to form a heart-
shaped or 2-spurred corolla (Fig. 17), the inner pair spoon-
Fio. 17. Flower of Dicentra
A, view of flower partly dissected: p, the larger outer petals; p', the spoon-
shaped inner petals. B, floral diagram. (After Le Maout and Decaisne)
shaped, inclosing the stamens and pistil. Stamens 6; the
filaments somewhat united into 2 sets, and the anthers in 2
sets close to the stigma. Stigma 2-crested. Pod lO-20-seeded.MUSTARD FAMILY
99
1.	D. Cucullaria Bernh. Dutchman** Breeches. Breeches
Flower. A low, stemless perennial, with a delicate scape and a
cluster of basal leaves with linear divisions, from a sort of bulb
made of small, scaly grains. Flowers in a 4-10-flowered simple
raceme, not fragrant. Spurs of the corolla longer than the pedicels;
corolla mostly white with a yellowish tip. Rich woods, common.
2.	D. canadensis Walp. Squirrel Corn, Wild Hyacinth. A
low, stemless perennial, with scape and leaves much as in Xo. 1, and
with small yellow tubers looking like grains of corn scattered along
the underground shoots. Corolla only heart-shaped at the base,
whitish or flesh-colored, very fragrant. Rich woods.
3.	D. spectabilis Lem. Bleeding Heart, Ear Drops. Stems
branching, recurved. Leaves large, twice compound in threes, the
divisions rather broad, like those of the common peony. Racemes
long, drooping, many-flowered. Flowers large, heart-shaped, bright
pink. Cultivated from China.
Vn. CORYDAUS Medic. (CAPNOIDES)
Leafy-stemmed biennial herbs (the American species).
Leaves much divided, alternate or nearly opposite. Racemes
terminal or opposite the leaves. Sepals 2, small. Petals 4 ;
corolla with a single spur at the base, on the upper side.
Capsule many-seeded.
1.	C. sempervirens L. Pale Corydalis. Plant erect, covered
with a bloom. Flowers pink-purple with yellow tips. Spur of the
corolla very short and rounded. Rocky woods.
2.	C. aurea Willd. Golden Corydalis. A low, spreading plant,
finally ascending. Corolla bright yellow, l-l1 in. long; the spur
shorter than the pedicel, somewhat bent. Shaded, rocky banks.
40. CRUCIFERAE. Mustard Family
Herbs with pungent, watery juice, and alternate leaves with-
out stipules. Sepals 4. often falling off early. Petals usually 4,
arranged in the form of a cross. Stamens 6, the 2 outer ones
shorter than the 4 inner ones. Fruit generally a pod, divided into
2 cells by a thin partition which stretches across from one to
the other of the 2 placentee. The flowers throughout the family
are so much alike that the genera and species cannot usually
be determined without examining the tolerably mature fruit.100
KEY AND FLORA
Fig. 18. Types of pods of Cruciferoe
A, flattened pod of Arab is, seeds in a single row in each cell: s, cross section
of pod, showing flattening parallel to the partition. B, pod of Radicula
palustris, seeds in several rows. C, nearly cylindrical pod of Sisymbrium.
D, beaked pod of white mustard (Si//apis alba). E, dried necklace-shaped
and beaked pod of radish (Raphanus Raphanistrum). F, flattened pod of
shepherd’s purse (Gapsella Bursa-pastor is): s, cross section, showing flat-
tening at right angles to the partition. G, flattened pod of Lepidium cam-
pestre; s, cross section, showing flattening at right angles to the partition.
(The pods natural size, the sections somewhat magnified.) (After Cosson
and De Saint-Pierre)
A
Pods short and flattened, contrary to the partition, splitting open when ripe.
Pod roundish.	Lepidium, IV
Pod triangular, inversely heart-shaped.	Capsella, Y
B
Pods globular or cylindrical, splitting open when ripe.
(a) Pods globular. Flowers yellow.	Lesquerella, IIIMUSTARD FAMILY
101
(b)	Pods cylindrical; seeds ellipsoid. Flowers very small, yellow.
Sisymbrium, VIII
(c)	Pods cylindrical; seeds globular. Flowers of moderate size,
yellow.	Brassica,	VII
(d)	Pods cylindrical; seeds in 2 rows; flowers white. Or pods
ovoid or ellipsoid; flower yellowish. Aquatic plants, or
growing	in wet soil.	Radicula,	IX
(e)	Pods cylindrical or angled ; seeds in a single row, flattened.
Flowers yellow.	Barbarea, X
C
Pock elongated, often jointed, tapering toward the tip, never splitting
open.	Raphanus,	VI
D
Puds fattened parallel to the partition, splitting open when ripe.
(a) Wild species ; leafy-stemmed; growing in or near water. Pods
linear.	Cardamine, XII
(h) Wild species ; stems naked below, bearing only 2 or 3 leaves.
Pods lanceolate.	Dentaria, XI
(c)	Wild species; leafy-stemmed; growing on dry ground or
rocks. Pods linear ; seeds usually winged or margined.
Arabis, XIII
(d)	Cultivated species. Pods round or roundish. Lobularia, I
(e)	Cultivated species; covered with a grayish down of star-
shaped hairs. Pods cylindrical.	Matthiola, II
I. LOBULARIA Desv. (KONIGA)
Perennial, though usually growing as an annual. Stems
branching, diffuse ; branches slender. Leaves small, entire,
downy, with forked hairs. Flowers small, white, in numerous
terminal racemes. Petals obovate, entire, twice as long as the
sepals. Filaments enlarged below. Pod round, compressed;
seeds 1 in each cell.*
1. L. maritima Desv. Sweet Alyssum. Stem weak, diffuse,
ascending, minutely downy. Lower leaves narrowed into a petiole,
the upper sessile. Racemes erect, many-flowered. Flowers fragrant,
pedicels ascending. Pod often pointed. Common in cultivation and
often run wild.*102
KEY AND FLORA
II.	MATTHIOLA R. Br.
Herbaceous or shrubby oriental plants, covered with a down
composed of star-shaped hairs. Flowers in showy racemes of
many colors, ranging from white to crimson. Stigmas large
and spreading. Pods nearly cylindrical, except for a promi-
nent midrib on each valve.
1. M. incana R. Br. Common Stock, Gillyflower. Biennial or
perennial, with somewhat woody stems. Cultivated in greenhouses
and gardens.
III.	LESQUERELLA Wats.
Low herbs with stellate hairs. Leaves simple. Flowers in
racemes, mostly yellow. Pod globular-inflated, with a trans-
lucent partition nerved from the apex to the middle. Seeds
few, several or many, flattened, marginless or nearly so.
1.	L. globosa Wats. Annual or biennial. Slender, somewhat
branched, 6-20 in. high, covered with fine stellate hairs. Basal
leaves 1-1 j in. long, oblong-obovate, obtuse. Stem leaves smaller,
linear or oblong, sessile. Raceme finally elongated with thread-like
diverging pedicels. Flowers light yellow. Style slender, much longer
than the small globose pod. Rocky banks and open places S. and W.
2.	L. argentea Pursh. Silvery Bladder Pod. Biennial or
perennial, 6-18 in. high, densely stellate-hairy. Leaves linear to
oblanceolate, blunt, entire, the lower ones 2—} in. long. Flowers
yellow. Pods downy, on recurved pedicels. Plains W.
IV.	LEPIDIUM L.
Annual. Stem erect, or sometimes diffuse. Leaves entire,
toothed, or pinnately divided. Flowers in a terminal raceme,
small, white. Petals short, sometimes wanting. Stamens 2,
4, or 6. Pod rounded or obcordate, flattened contrary to the
partitions.*.
1.	L. virginicum L. Peppeiiorass, Birds' Pepper. Tongue
Grass. Stem erect, smooth, much branched, 1-2 ft. high. Lower
leaves obovate in outline, pinnately cut with dentate lobes ; upper
leaves lanceolate, dentate, slightly downy. Flowers on slender
pedicels; petals present, sometimes reduced in the later flowers.
Stamens 2. Pod round. A weed growing in waste places.*
2.	L. campestre R. Br. Field Cress. Annual or biennial. Stem
erect, branching above, downy, 8_18 in. high. ISasal leaves entire orMUSTARD FAMILY
103
pinnately cut toward the base, obtuse ; stem leaves oblong or lanceo-
late, entire or somewhat toothed, with an arrow-shaped clasping
base. Flowers white or yellowish, on stout pedicels. Pods ovate,
winged, slightly notched, tipped with a very small persistent style.
Fields and waste ground, becoming a troublesome weed. Naturalized
from Europe.
V.	CAPSELLA Medic. (BURSA)
Annual. Stem erect, downy, with branched hairs. Racemes
terminal, becoming elongated in fruit. Flowers small, white.
Pod obcordate or triangular, flattened contrary to the parti-
tion, shorter than the spreading pedicels.*
1. C. Bursa-pastoris Medic. Shepherd’s Perse. Root long and
straight. Stem branching above, downy below, smooth above.
Lower leaves forming a rosette at the base of the stem, irregularly
lobed or pinnately cut; stem leaves lanceolate, clasping, toothed or
entire. Sepals downy, about \ as long as the petals. Pod triangular,
notched, or cordate at the apex. Seeds several in each cell. A com-
mon weed.*
VI.	RAPHANUS L.
Annual or bieunial herbs. Basal leaves lyrate. Flowers in
long racemes, white or yellow, purple-veined. Sepals erect.
Pods rather long, slender-beaked, not splitting open but some-
times breaking across into 1-seeded joints.
1.	R. Raphanistrum L. Wild Radish, Jointed Charlock. A
stout, hairy annual, 1-2 ft. high. Leaves cut into remote segments,
which are coarsely toothed or serrate; terminal segment largest.
Flowers yellow, turning whitish or purplish. Pods necklace-shaped,
and with a long beak. A common weed eastward. Naturalized from
Europe.
2.	R. sativus L. Common Radish. Similar to No. 1, but with
pink or white flowers. Root fleshy, conical or turnip-shaped. Pod
fleshy, 2-3-seeded, the beak often longer than the seed-bearing portion.
Cultivated from Asia and occasionally self-sown in cultivated ground.
VII.	BRASSICA L.
Branching herbs. Leaves often pinnately cut. Flowers in
racemes, rather large, yellow. Sepals spreading. Pods nearly
cylindrical, sometimes tipped with a beak- which does not
open. Seeds globular.104
KEY AND FLORA
1.	B. alba Boiss. White Mustard. Stem 2-5 ft. high, with
reflexed hairs. Upper leaves pinnately cut. Pods borne on spreading
pedicels, bristly, with a sword-shaped, 1-seeded beak occupying more
than half their length. Seeds pale. Cultivated from Europe and
introduced to some extent.
2.	B. arvensis Ktze. Charlock. Stem 1-2 ft. high; it and the
leaves rough-hairy. Upper leaves rhombic, barely toothed. Flowers
|-f in. across, somewhat corymbed, bright yellow. Pods knotty,
spreading, at least |. of each consisting of a 2-edged, 1-seeded beak.
A showy, troublesome weed in grain fields. Naturalized from Europe.
3.	B. juncea Cosson. Similar to the preceding, but nearly or
quite smooth. Pedicels slender. Beak slender, conical, not contain-
ing a seed. Naturalized from Asia and becoming very abundant
eastward.
4.	B. nigra Koch. Black Mustard. Stem 3-6 ft. high, some-
what hairy. Lower leaves lyrate, with the terminal lobe much the
longest; stem-leaves linear-lanceolate, entire or toothed, smooth.
Pods awl-shaped, 4-angled, smooth, lying against the stem; seeds
brownish, more biting than in No. 1. Cultivated from Europe and
introduced.
VIII. SISYMBRIUM L.
Annual or biennial herbs. Radical leaves spreading ; stem
leaves alternate, often eared at the base. Flowers in loose
racemes, usually yellow, often bracted. Pods generally nar-
rowly linear, cylindrical, or 4-6-angled ; seeds many, ellipsoid,
not margined.
1.	S. officinale Scop., var. leiocarpum. Hedge Mustard. Stems
branching, stiff. Leaves runcinate-toothed or lobed. Flowers very
small, pale yellow. Pods somewhat 6-sided, awl-shaped, smooth,
closely pressed against the stem. An unsightly weed in waste ground.
Naturalized from Europe.
2.	S. canescens Nutt. Tansy Mustard. Stem 1-2 ft. high.
Leaves twice pinnately cut, usually covered with grayish down.
Flowers very small, yellowish. Pods oblong, club-shaped, 4-angled,
borne on pedicels projecting almost horizontally from the stem, in
long racemes. Common westward.
IX. RADICULA Hill. (RORIPA)
Annual or biennial, mostly aquatic plants. Stems erect or
diffuse, often widely branching. Leaves simple, pinnately
lobed. Flowers small, white or yellow. Sepals spreading.MUSTARD FAMILY
105
Stamens 1-6. Pod short and broad or nearly linear ; seeds
numerous, in 2 rows in each cell.*
1.	R. Nasturtium-aquaticum B. & R. Watercress. Aquatic herbs.
Stems smooth, diffuse, rooting at the joints. Leaves with 3-9 rounded,
pinnate lobes, the terminal lobe much the largest. Racemes elon-
gating in fruit. Petals white, twice the length of the sepals. Pods
linear, 1-j in. long, on slender, spreading pedicels. In ditches and
slow streams. Often used for salad.*
2.	R. sinuata Greene. .Spreading Yellow Cress. Perennial.
Stems low and spreading. Leaves oblong or lanceolate, pinnately
cleft, the lobes obtuse. Flowers yellow, about a in. in diameter.
Pods linear oblong, i-f in. long. River bottoms and moist ground W.
3.	R. palustris Mcench. Yellow Watercress. Annual or bien-
nial. Stem erect, branched, slightly downy. Leaves irregularly
lyrate, the lower petioled, the upper sessile. Flowers small ; petals
yellow. Pods linear, spreading, longer than the pedicels. In wet
places.*
4.	R. Armoracia Robinson, PIorse-Radish. A coarse herb, with
large leaves, from stout, long, cylindrical rootstocks filled with a very
sharp, biting juice. Basal leaves long-petioled, linear-oblong, obtuse,
regularly scalloped ; stem-leaves sessile. Racemes in panicles. Pods
obovoid, on long, slender pedicels ; seeds seldom or never ripening.
Probably from Europe ; cultivated and often introduced in damp
ground.
X. BARBAREA R. Br.
Mostly biennials, somewhat resembling Radicula. Flowers
yellow. Pod elongated, linear, cylindrical, or somewhat 4-sided.
Style short. Seeds in 1 row in each cell, not margined.
1. B. vulgaris R. Br. Winter Cress, Yellow Rocket. Smooth,
with tufted stems 1-2 ft. high. Lower leaves petioled, pinnately cut,
with 1-4 pairs of lateral divisions and a rounded, much longer
terminal one; upper leaves nearly or quite sessile. Flowers | in. in
diameter or less. Pods erect or spreading. Fields and waste ground.
Introduced from Europe into the eastern and central states.
XI. DENTARIA L.
Stems naked below, 2-3-leaved above, from a thickish, more
or less knotted or interrupted rootstock. Flowers rather
large, in early spring. Pod lance-linear, flattish ; seeds in 1
row, wingless; seedstalks broad and flat.106
KEY AND FLORA
1.	D. diphylla L. Two-Leaved Toothwort, Pepper Root,
Crinkle Root. Rootstock long, often branched, toothed, eatable,
with a flavor like that of cress or radish. Stem leaves 2, close
together, each composed of 3 ovate-diamond-shaped and toothed or
eremite leaflets; the basal leaf like the stem leaves. Flowers white.
Damp woods.
2.	D. laciniata Muhl, Crow's-Foot. Rootstock short, necklace-
like. Stem leaves 3-parted ; basal leaf often absent. Flowers white
or rose color. Woods.
XII. CARD AMINE L.
Annual or perennial. Rootstock often scaly or bulb-bearing.
Stem erect or ascending, usually smooth. Leaves more or
less divided. Flowers in terminal racemes, white or purple.
Petals rather large. Stamens 6. Fruit a linear, flattened pod ;
seeds several, in a single row in each cell.*
1.	C. rhomboidea DC. Bulbous Cress. Perennial. Root tuber-
ous. Stum simple, erect, smooth, without runners, 9-1H in. tall.
Lower leaves long-petioled, ovate, orbicular, or heart-shaped, often
angled or toothed; the upper short-petioled or sessile, lanceolate or
oblong, toothed or entire. Pedicels |-1 in. long. Petals white, in.
long. Pod erect, linear-lanceolate, tipped by the persistent style;
seeds round-oval. Cool, wet places.*
2.	C. pennsylvanica Muhl. Bitter Cress. Annual. Stem slender,
erect, simple, or with a few slender branches, 6-15 in. tall. Leaves
mostly in a cluster at the base of the stem, pinnately divided, the
terminal lobe roundish, the lateral lobes narrower, somewhat hairy
above; stem leaves nearly linear. Flowers small. Petals white, longer
than the sepals. Stamens 4. Pods linear, erect on erect pedicels,
about 1 in. long; seeds oval. I n wet places.*
XIII. ARABIS L.
Annual or perennial herbs, smooth, or with forked or star-
shaped hairs. Basal leaves spatulate; stem leaves sessile.
Flowers usually white. Petals entire, usually with claws.
Pods linear, flattened ; seeds often margined or winged.
1. A. hirsuta Scop. A rough-hairy, erect, leafy-stemmed biennia],
1-2 ft. high. Leaves simple; stem leaves oblong or lanceolate, entire
or toothed, somewhat clasping, often with an arrow-shaped base.
Flowers small, greenish-white, the petals somewhat longer than the
sepals. Pods and pedicels upright. Style almost wanting. Seeds
roundish, somewhat wing-margined. Rocks, X.CAPER FAMILY
107
2.	A. lsevigata Poir. A smooth, leafy-stemmed biennial, 1-2 ft.
high, covered with a bloom. Stem leaves lance-linear, clasping.
Flowers small and whitish, the petals hardly longer than the sepals.
Pods 2-1 in. long, flattened, spreading, and recurved; seeds broadly
winged. Rocks.
3.	A. canadensis L. Sickle Pod. An upright, leafy-stemmed
biennial, 2-1 ft. high, simple or slightly branching above, sometimes
slightly hairy at the base. Stem leaves sessile, oblong-lanceolate,
pointed at both ends, downy; the lower ones toothed. Flowers small,
whitish, the petals twice as long as the sepals. Pods sCythe-shaped,
much flattened, hanging from hairy pedicels ; seeds broadly winged.
Ettjky hillsides.
41. CAPPARIDACEAJ. Caper Family
Herbs (when growing in cool temperate regions), with bitter
or nauseous juice. Leaves alternate, usually palmately com-
pound. Flowers often not actinomorphic, usually bisexual.
Sepals 4-8. Petals 4 or wanting. Stamens G or more. Ovary
and pod 1-celled, with 2 rows of ovules ; seeds kidney-shaped.
I. POLANISIA Raf.
Ill-smelling annual plants covered with glandular or clammy
hairs. Sepals distinct, spreading. Petals with claws, notched
at the tip. Stamens 8-32. of various lengths. Receptacle not
lengthened. Pod linear or oblong, rather large, many-seeded.
1. P. graveolens Raf. A very strong-scented, leafy, branching herb,
6-15 in. high. Leaves with 3 oblong leaflets. Flowers small, pinkish
and yellowish-white, in the axils of leafy bracts, in terminal racemes.
Stamens S-12, not much longer than the petals. Pod about 2 in.
long, slightly stalked. Gravelly banks.
II. CLEOME L.
Mostly annual herbs. Stems branched. Leaves petioled,
simple, or with 3-7 entire or serrate leaflets. Flowers in
braeted racemes. Sepals 4, often persistent. Petals 4, often
long-clawed, nearly equal, entire. Stamens 6, filaments thread-
like, usually projecting much, but sometimes 1-3 much shorter
than the others, inserted on the short receptacle. Ovary on a108
KEY AND FLORA
short stalk with a small gland at its base. Fruit a slender
capsule on an elongated stalk.*
1. C. serrulata Pursh. Rocky Mountain Bee Plant, Stinking
Clover. A smooth plant 2 ft. or more high. Leaves with 3 leaflets.
Flowers pink, showy, in leafy-bracted racemes. Pod oblong to linear,
1^2 in. long. Cultivated as an ornamental plant and also for bees
Common in a wild condition W.
42. RESEDACEAE. Mignonette Family
Annual or perennial herbs, rarely shrubs. Leaves alternate,
simple or pinnately cut. Flowers racemed or spiked, bracted.
Calyx 4-7-parted, often not actinomorphic. Petals 4-7,
hypogynous, often unequal and cleft or notched. Stamens
usually many, borne on a large one-sided hypogynous disk.
Ovary of 2-6 carpels, which are more or less united into a
single 1-celled, many-seeded, several-lobed or -horned pistil,
which opens at the top before the seeds ripen.
RESEDA L.
Annual. Stems diffuse, widely branched. Leaves sessile,
entire or lobed, smooth. Flowers in close racemes or spikes.
Petals 4-7, toothed or cleft. Stamens 8-MO, inserted at one
side of the flower. Capsule 3-6-lobed.*
1. R.odorataL. Mignonette. Stem widely diffuse, 6-12 in. high,
smooth. Leaves wedge-shaped, entire or 3-lobed. Flowers small,
greenish-yellow, very fragrant. Petals deeply 7-13-cleft. Often cul-
tivated. From Egypt.*
43. SARRACENIACEiE. Pitcher Plant Family
Perennial, apparently stemless, marsh herbs. Leaves tubu-
lar or trumpet-shaped. Flowers single, nodding, on a naked
or bracted scape. Sepals 4-5, colored, persistent. Petals 5,
deciduous, or sometimes wanting. Stamens numerous. Pistil
compound, 5-celled, many-ovuled ; style terminal, nearly as
broad as the flower, shield-shaped.*SAXIFRAGE FAMILY
109
SARRACENIA L.
Rootstock short, horizontal; scape naked. Leaves trumpet-
shaped, with a wing extending nearly to the base and a broad
blade at the apex ; tube hairy within, with downward-pointing,
stiff-hairs. Calyx 3-bracted. Petals obovate, drooping or in-
curved. Style umbrella-shaped, 5-angled ; stigmas at the hooked
angles of the style on the under surface. Capsule globose,
rough. [The tubular leaves usually contain more or less water
and dead insects, the latter having been attracted by a honey-
like secretion near the opening.]
1. S. purpurea L. Sidesaddle Flower. Leaves ascending,
curved, broadly winged, purple-veined, 4-8 in. long; blade erect,
round-cordate, hairy on the inner side. Scapes 12-18 in. tall ; flower
deep purple, about 2 in. broad; style yellowish. Moss}' swamps.*
44. SAXIFRAGACE2E. Saxifrage Family
Herbs or shrubs. Leaves alternate or opposite, generally
without stipules. Sepals 4 or 5, more or less joined with each
other and not usually hypogynous. Petals as many as the
sepals and alternate with them. Stamens as many as the
petals and alternate with them, or 2-10 times as many. Ovary
usually of two carpels, united only at the base or more or less
throughout. Fruit generally a 1-2-celled capsule, sometimes
a berry; seeds many, with endosperm.
I. SAXIFRAGA L.
Herbs with simple or palmately cut leaves and generally
cymose or panicled flowers. Sepals 5, more or less united.
Petals 5, entire, inserted on the calyx tube. Stamens 10.
Capsule consisting of 2 (sometimes more) ovaries, united at
the base, separate and diverging above.
1. S. pennsylvanica L. Swamp Saxifrage. Perennial. Leaves
4-8 in. long, oblong-lanceolate and tapering to the base, slightly
toothed. Scape 1-2 ft. high, bearing an oblong cluster of small
greenish flowers, at length diffusely panicled. Petals greenish-yellow110
KEY AND FLORA
(rarely crimson), linear-lanceolate, hardly longer than the calyx
lobes. Boggy ground.
2. S. virginiensis Miclix. Early Saxifrage, Mayflower.
Perennial. Apparently stemless, with a cluster of spatulate, obovate,
or wedge-shaped basal leaves, and a scape 3-9 in. high, which bears
a dense cluster of small white flowers, becoming at length a panicled
cyme. Petals white, oblong, much longer than the calyx. Rocks and
dry hillsides N.
H. TIARELLA L.
Perennial. Flowers white, in racemes. Calyx white, 5-
parted, nearly hypogynous. Corolla of 5 very narrow petals,
with slender claws, alternating with the calyx lobes. Stamens
10, springing from the calyx tube and extending outside the
flower. Styles 2, long and slender; ovary 1-celled, 2-beaked.
In fruit one of the carpels grows to be much larger than the
other, thus making up the main bulk of the thin, dry pod,
which has a few seeds attached near the bottom.
1. T. cordifolia L. False Miterwort. Stem 5-12 in. high,
usually leafless, sometimes with 1 or 2 leaves. Rootstock bearing
runners in summer. Leaves heart-shaped, sharply lobed, the lobes
with acute or mucronate teeth, somewhat hairy above, downy be-
neath. Raceme short and simple. Rocky woods, especially N.
III. HEUCHERA L.
Perennials, with a tall scape and roundish, heart-shaped
basal leaves. Flowers rather small, greenish or purplish, in a
long panicle. Calyx 5-cleft, the tube somewhat perigynous.
Petals 5, small, spatulate, inserted with the 5 stamens on the
margin of the calyx tube. Capsule 1-celled, 2-beaked, splitting
open between the beaks.
1. H. americana L. Common Alum Root. Scapes 2-4 ft. high,
rather slender, often several from the same root, hairy and glandu-
lar. Basal leaves large and long-petioled, abundant, somewhat
7-lobed. Flowers whitish with a tinge of purple, in a loose panicle.
Stamens projecting considerably outside the flower, their anthers
of a bright terra cotta color, 'the root is very astringent and is
somewhat used as a home remedy. Shaded banks, fence rows, and
thickets; common W.SAXIFRAGE FAMILY
111
IV. MITELLA L.
Delicate perennial herbs. Flowers small, pretty, in a simple
raceme or spike. Calyx 5-cleft, slightly perigynous. Petals 5,
cut-fringed, inserted on the throat of the calyx tube. Stamens
5 or 10, not projecting from the calyx tube. Styles 2, very
short. Ovary and pod 2-beaked, globular, 1-celled.
1. M. diphylla L. Two-Leaved Bishop’s C'ap, Fringe C'up,
Fairy Cup. Stemless, with long-petioled, roundish-cordate root
leaves, and a scape about 1 ft. high, bearing 2 opposite, nearly ses-
sile leaves. Flowers many, racemed, white. Woods.
V.	PHILADKLPHUS L.
Shrubs. Leaves simple, opposite, 3-5-ribbed, petioled, with-
out stipules. Flowers solitary or in cymes, large, white. Calyx
tube top-shaped, the epigynous limb 4-5-parted, persistent.
Petals 4—5, rounded or obovate. Stamens 20-40, shorter than
the petals. Ovary 3-5-celled, many-seeded; styles 3-5, more
or less united.*
1.	P. grandiflorus Willd. Large-Flowered Syrixga. Shrub,
6-10 ft. high; branches downy. Leaves ovate or ovate-oblong,
taper-pointed, sharply serrate, downy, 3-ribbed. Flowers solitary or
2-3 together, white, 11—2 in. broad, not fragrant. Calyx lobes ovate,
taper-pointed, about twice as long as the tube. On low ground S.,
and cultivated*
2.	P. coronarius L. Garden Syrixga. Shrub, 8-10 ft. high.
Leaves oval or ovate, obtuse at the base, acute at the apex, remotely
toothed, smooth above, downy beneath. Flowers in terminal racemes,
creamy white, 1-1 V in. wide, very fragrant. Calyx lobes ovate, acute,
longer than the tube. Common in cultivation. From southern Europe.*
VI.	DEUTZIA Tkunb.
Shrubs with simple, opposite leaves, without stipules.
Flowers all bisexual and alike, racemed or panicled, showy.
Calyx lobes 5. Petals 5. Stamens 10, 5 long and 5 short;
filaments flat and 3-pronged, the middle prong bearing an
anther. Styles 3-5, slender. Pod 3-5-celled.
1, D. gracilis Sieb. & Zucc. About 2 ft. high, loosely spreading.
Leaves ovate-lanceolate, sharply serrate, smooth. Flowers white,
very numerous. Cultivated from Japan, often in greenhouses.112
KEY AND FLORA
VII. RIBES L.
Shrubs. Leaves palmately veined and lobed, sometimes with
stipules. Calyx tube egg-shaped, its 5 epigynous lobes usually
colored like the petals. Petals 5, small, generally inserted on
the throat of the calyx tube. Stamens 5, inserted with the
petals. Styles 2; ovary 1-celled, with 2 placentas on its walls,
becoming in fruit a pulpy (usually eatable) berry.
1.	R. Cynosbati L. Prickly Wild Gooseberry. Spines in
pairs. Leaves long-petioled, downy, heart-shaped, cut-dentate. The
single style and the stamens not projecting from the calyx tube.
Berries generally prickly, brownish-purple, pleasant-flavored.
2.	R. gracile Michx. Slender Gooseberry. Spines slender,
solitary, or in pairs or threes. Leaves with slender petioles, some-
what downy when young, round, the base truncate or obtuse, 3-5-
lobed, the divisions obtuse and toothed. Flowers often in threes,
white or greenish, drooping. Calyx lobes longer than the tube;
stamens decidedly projecting from the tube. Berries smooth, red-
dish-purple. Dry or rocky soil W.
3.	R. rotundifolium Michx. Smooth Wild Gooseberry. Spines
few and short, prickles few or absent. Leaves roundish, lobed, with
the lobes crenate-dentate, often downy. Peduncles slender ; flowers
inconspicuous. Calyx lobes reflexed. Styles and stamens projecting
decidedly from the calyx tube. Berries smooth.
4.	R. oxyacanthoides L. Northern Gooseberry. Spines usually
solitary, often numerous. Leaves petioled, their lower surfaces and
petioles commonly downy. Flowers 1-3 together, on short pedicels,
greenish-purple or white. Berry | in. in diameter, smooth, reddish-
purple. Low grounds and damp woods N.
5.	R. americanum Mill. Wild Black Currant. Branches thorn-
less, erect. Leaves resinous-dotted, somewhat heart-shaped, 3-5-lobed,
toothed. Flowers large, whitish. Calyx tubular-bell-shaped, smooth.
Fruit round-ovoid, black, smooth. In woods.
6.	R. vulgare Lam. Red Currant. Stems more or less reclining.
Leaves somewhat heart-shaped, obtusely 3-5-lobed. Racemes droop-
ing. Limb of the calyx wheel-shaped. Berries acid, eatable, red
or light amber-colored. Cultivated from Europe ; also somewhat
naturalized.
7.	R. odoratum Wendland. Golden Currant, Flowering C.,
Missouri C., Clove Currant. A much taller shrub than the com-
mon red currant. Leaves 3-lobed, toothed. Racemes short and loose.
'Lube of the yellow calyx much longer than its limb. Flowers very
fragrant. Fruit brownish-black, barely eatable.SYCAMORE FAMILY
113
45. PLATANACE.®. Sycamore Family
Trees, with simple, alternate, petioled leaves, with stipules ;
the bases of the petioles covering the buds. Flowers monoe-
cious, in axillary, long-peduncled, globose heads. Calyx and
corolla very inconspicuous, each consisting of 3-8 minute
scales, or wanting. Stamens as many as the sepals and oppo-
site them. Pistils several, inversely conical, hairy at the base ;
styles long. Capsules 1-seeded.*
PLATAN US L.
Characters of the family.
1. P. occidentalis L. Sycamore, Bcttoxwood. A large tree,
bark light-colored, smooth, peeling off in large, thin plates. Leaves
large, round-heart-shaped, angularly lobed' and toothed, densely
white-woolly when young, becoming smooth with age; stipules
large, toothed. Fruit in a globular, drooping head, which remains
on the tree through the winter, dropping the seeds very slowly.
Common on river banks and in swampy woods.*
46. ROSACEAS. Rose Family
Herbs, shrubs, or trees. Leaves alternate or rarely opposite,
simple or compound, with stipules. Calyx 5-lobed. Petals o,
rarely wanting, inserted with the stamens on the edge of a disk
that lines the calyx tube. Stamens many, rarely 1 or few.
Carpels 1 or more, distinct or united, superior or inferior.
Fruit a pome, a drupe or group of drupes, or 1-several akenes
or follicles, rarely a berry or capsule. The relation of the
parts of the flower to each other and to the receptacle is shown
in Fig. 19.
A
Ripe carpels not inclosed within the calyx tube.
1. Fruit dry.
(a) Carpels 1—5. inflated.	Physocarpus, I
(J) Pods 5-8, not inflated. 2-several-seeded. Spiraea, TI114
KEY AND FLORA
(c) Carpels 5-15 (usually 10), 1-seeded. Filipendula, X
(rf) Akenes '2-6, styles not lengthening after flowering.
Waldsteinia, VIII
(e) Akenes many, on a dry receptacle. Styles not length-
ening.	Potentilla, IX
(/) Akenes many, on a dry receptacle. Styles lengthening
after flowering, forming tails to the akenes.
Geum., XI
2. Fruit fleshy.
(a) Akenes several-many, becoming little drupes.
Rubus, XII
(/>) Akenes many, dry on ripening, on a fleshy, eatable
receptacle.	Fragaria, VII
(c) Pistil solitary, becoming a drupe	Prunus, XIV
A
Fig. 19. Pistils in the Rose Family
A, Prunus-type; B, Potentilla-type; C, Rosa-type, c, calyx; o, ovary
B
ltipe carpels inclosed within the calyx tube.
1. Fruit a pome.
(а)	Carpels more than 2-seeded ; seeds covered with a muci-
laginous pulp. Fruit 5-celled.	Cydonia, III
(б)	Carpels 2-seeded (except in some cultivated varieties);
seeds without pulp. Fruit 5-celled.	Pyrus, IV
(<•) Carpels 2-seeded ; fruit 10-celled.	Amelanchier, VROSE FAMILY
115
2. Fruit not evidently a pome, or not at all so.
(«) Trees or shrubs. Fruit with a stone usually of 2-5 bony
1-seeded carpels united.	Crataegus, VI
(b) Shrubs. Fruit with many akenes borne on the interior
of a fleshy calyx tube.	Rosa, XIII
I. PHYSOCARPUS Maxim. (OPULASTER)
Shrubs. Leaves simple, palmately veined and lobed, peti-
ole!. Flowers white, in terminal corymbs. Calyx spreading,
5-lobed. Petals 5. Stamens numerous. Pistils 1-5, short-
stalked ; stigma terminal; ovaries becoming inflated at matu-
rity, 2-4-seeded, splitting open.*
1. P. opulifolius Maxim. Xine-Bark. A spreading shrub, 3-6 ft.
high, the old bark separating into thin strips. Leaves petioled,
broadly ovate or rounded, often heart-shaped, 8-lobed, the lobes
doubly crenate-serrate; stipules deciduous. Corymbs terminal, pe-
duncled, nearly globose, downy, many-flowered. Follicles 3-5, much
/longer than the calyx, smooth and shining, obliquely tipped by the
persistent style. Banks of streams.*
II. SPIR2EA L.
Shrubs with simple leaves. Flowers perfect, in terminal
or axillary racemes or panicles. Calyx 5-cleft, persistent.
Petals 5. Stamens numerous. Pistils usually 5, free from the
calyx and alternate with its lobes. Follicles not inflated, 2-
several-seeded.*
1.	S. salicifolia L. "Willow-Leaved Stie.ea. Shrubs 2-5 ft.
high, branches smooth. Leaves lanceolate to oblong-ovate, smooth
or nearly so, sharply serrate, base usually wedge-shaped, pale be-
neath; stipules deciduous. Flowers white or pink, panicle dense-
flowered; follicles smooth. On low ground.*
2.	S. cantoniensis Lour. Bridal Wreath. Shrubs 2-1 ft. tall;
branches long, slender, and spreading. Leaves lanceolate, serrate,
sometimes 3-lobed or pinnatifid, with a bloom beneath. Flowers
white or pinkish, in axillary racemes or corymbs, often forming
long wreaths. Follicles smooth. Cultivated from Europe.
3.	S. tomentosa L. Hardback. Erect shrubs. Stems densely
downy, usually simple. Leaves simple, ovate or oblong, serrate,
densely rusty-downy below, smooth and dark green above. Flowers116
KEY AND FLORA
small, pink or purple, in a close panicle. Follicles 5, densely downy,
several-seeded. On low ground S., and along fence rows and in pas-
tures N., where it is a troublesome weed.*
III. CYDONIA L.
Trees or shrubs. Leaves simple, toothed or lobed, stipules
deciduous. Flowers usually solitary, white or pink. Calyx
tube urn-shaped, 5-lobed, its epigynous lobes acute, spreading,
persistent. Petals 5. Stamens numerous, inserted with the
petals on the calyx tube. Styles 2-5, mostly 5, united at the
base; ovary 5-celled, seeds many in each cell. Fruit a pome,
globose, usually depressed or hollowed at the extremities;
flesh without hard grains.*
1.	C. vulgaris Pers. Quince. Shrub 6-12 ft. high. Leaves oblong-
ovate, acute at the apex, obtuse at the base, entire, downy below.
Flowers large, white or pink. Fruit ovoid, downy. Cultivated.*
2.	C. japonica Pers. Japan Quince. A widely branching shrub,
8-0 ft. high; branches with numerous straight spines. Leaves ovate-
lanceolate, acute at each end, smooth and shining, serrulate; stipules
conspicuous, kidney-shaped. Flow'ers in nearly sessile axillary clusters,
bright scarlet. Fruit globose. Common in cultivation.*
IV. PYRUS L.
Trees. Leaves simple, stipules small, deciduous. Flowers
in cymes, large, white or pink. Calyx urn-shaped, 5-cleft, its
epigynous lobes acute. Petals rounded, short-clawed. Stamens
numerous, borne with the petals on the calyx tube. Styles 5,
distinct or slightly united at the base. Fruit a pome, with
about 2 seeds in each carpel.*
I!. FI. species 2-5 (Mains) ; species 6 (Amnia); species
7, 8 (Sor/nts).
1. P. communis L. Pear. A tree, often very large; head usually
pyramidal, branches often thorny. Leaves thick and leathery, ovate
or oval, acute, finely serrate or entire, downy when young, becoming
smooth with age; petioles slender. Cymes few-se-veral-fiowered,
terminal, and at the ends of “fruit spurs” grown the previous sea-
son. Flowers white. kStyles not united. Fruit ohovoid, with hard
gritty grains near the core. A European and Asiatic tree common
in cultivation.*ROSE FAMILY
117
2.	P. angustifolia Ait. Narrow-Leaked Crab Apple. A small
tree, witli smooth, light gray bark. Leaves lanceolate or oblong, ser-
rate. downy when young, acute at the base, short-petioled. Corymbs
few-flowered. Flowers pink, fragrant, about 1 in. broad. Styles
smooth, distinct. Fruit nearly globose, about J in. in diameter, very
sour. In open woods, Pennsylvania, lVest, and South.*
3.	P. coronaria L. American Crab Apple. A small tree, with
smooth bark. Leaves triangular or oval-lanceolate, acutish or rounded
or a little heart-shaped at the base, cut-serrate and often somewhat
3-lobed, slender-petioled, soon smooth. Flowers large, few in a clus-
ter, pale rose color, very sweet-scented. Fruit bright green, turning
yellowish, sometimes 1 k in. in diameter, flattened at right angles to the
pedicels, very fragrant. Glades, western New York, IVesl. and South.
4.	P. ioensis Bailey. Western Crab Apple. A small tree, much
like P. coronaria but with the leaves white-downy beneath, ovate-
lanceolate and narrowed at the base. Fruit dull green with light
dots, about 1 in. in diameter. Thickets IV.
5.	P. Malus L. Apple. A tree with a rounded top and dark-
colored bark. Leaves oval or ovate, obtuse or pointed, dentate or
nearly entire, rounded at the base, smooth above, downy beneath.
Cymes few-many-flowered. Flowers large, white or pink. Calyx
downy. Fruit depressed-globose to ovoid, hollowed at the base and
usually at the apex. Cultivated from Europe and often running
wild in old pastures, etc., E.*
6.	P. arbutifolia L. f. Chokeberry, Choke Pear, Dogberry.
A shrub, 5-8 ft. high. Leaves oblong or oblanceolate, finely serrate,
downy beneath, short-petioled. Flowers in a downy compound cyme,
small, white or reddish. Fruit pear-shaped or nearly globular, not
larger than a currant, very dark purple, dry and puekery. There is
also a smooth-leaved variety with black fruit. ,Swamps and damp
thickets, especially N.E.
7.	P. americana DC. American Mountain Ash. A tall shrub
or small tree. Leaves odd-pinnate. Leaflets oblong-lanceolate, taper-
pointed, sharply serrate, smooth, bright green. Flowers small, white,
in large flat, compound cymes. Fruit bright scarlet, not larger than
currants. Common X. and often cultivated.
8.	P. Aucuparia Ehrh. European Mountain Ash or Rowan
Tree. Larger than Xo. 7. Leaflets paler, downy beneath. Fruit
larger, about l in. in diameter. Cultivated from Europe.
V. AMELANCHEER Medic.
Shrubs or small trees, with smooth gray bark. Leaves sim-
ple, sharply serrate, petioled. Flowers white, in racemes.118
KEY AND FLORA
Calyx tube 5-eleft, its lobes epigynous. Petals oblong. Styles
5, united below; ovary 5-celled, 2 ovules in each cell, often
only 1 maturing. Fruit small, berry-like.*
1.	A. canadensis Medic. Service Berry, Juneberry, Shad
Bosh, Sugar Plum, Sugar Pear, Wild Pear. A small tree,
branches downy when young, soon becoming smooth. Leaves ovate
to elliptical, finely and sharply serrate, acute at the apex, usually
obtuse or cordate at the base. Racemes slender, many-flowered,
appearing before or with the leaves. Flowers showy. Petals 4 or 5
times the length of the smooth calyx lobes. Fruit globose, dark red,
edible. In rich woods. Extremely variable in height and in shape
of leaves.*
2.	A. spicata K. Koch. Round-Leaved Juneberry. Much like
A. canadensis, but with the leaves broadly oval, ovate, or almost
orbicular, and usually rounded at both ends. Woods and thickets,
especially N.
VI.	CRATiEGUS L.
Shrubs or small trees, mostly with numerous strong spines,
wood very hard. Leaves serrate, lobed or deeply incised,
petioled. Flowers white or pink, in terminal corymbs or
sometimes solitary. Calyx tube urn-shaped, 5-cleft, the limb
persistent. Petals round. Stamens few or many. Styles 1-5,
distinct; ovules 1 in each cell. Fruit a small pome with bony
carpels.* [The species are hard to distinguish and are not
very perfectly defined. Probably more than 60 species occur
within the limits of this flora.]
VII.	FRAGARIA L.
Perennial scape-bearing herbs, with runners. Leaves with
3 leaflets ; stipules united to the petiole. Flowers (of Ameri-
can species) white. Calyx hypogynous, 5-parted, 5-brac,ted,
persistent. Petals 5. Stamens many. Carpels many, on a
convex receptacle. Akenes of the ripe strawberry many, very
small, more or less imbedded in the large, sweet, pulpy
receptacle.
1. F. virginiana Duchesne. Wild Straw'berry. Leaflets thick,
oval to obovate, coarsely serrate, somewhat hairy. Scape usually
shorter than the petioles, fewT-flowered. Fruit ovoid, akenes imbedded
in deep pits. Common.*ROSE FAMILY
119
2. F. vesca L. European Strawberry. Leaflets ovate or broadly
oval, dentate above, wedge-shaped below, slightly hairy. Scape usu-
ally longer than the petioles. Fruit globular or oval, akenes adherent
to the nearly even surface of the receptacle. Common in cultivation.
Many of the cultivated varieties of strawberry are hybrids between
the two described above. The following variety is by some regarded
as distinct.*
Var. americana Porter. American Wood Strawberry. Slender,
smooth or silky-downy. Leaflets very thin, sharply cut-toothed, downy
beneath with close-lying silvery hairs, the down of the scapes, the
pedicels, and sometimes of the leafstalks also, usually close-lying.
Calyx lobes reflexed in fruit. Rocky woods.
VIII. WALDSTEINIA Willd.
Stemless perennial herbs. Leaves 3-5-lobed or -divided.
Flowers several, rather small, yellow, on a bracted scape.
Calyx tube top-shaped; the limb spreading, with sometimes
little bracts alternating with the lobes. Petals 5. Stamens
many. Style 2-6. Akenes few, on a dry receptacle.
1. W. fragarioides Tratt. Barren Strawberry. A low herb with
much the appearance of a strawberry plant. Leaflets 3, broadly
wedge-shaped, crenate-dentate. Scapes many-flowered; the flowers
rather pretty. Wooded hillsides.
IX. POTENTILLA L.
Perennial herbs, rarely shrubs. Leaves compound ; stipules
united to the petiole. Flowers white or yellow, rarely red;
solitary or in cymes. Calyx hypogynous, 5-cleft, with 5 little
bracts alternating with its lobes. Petals 5. Stamens many.
Carpels usually many, on a dry convex or concave receptacle ;
styles falling off from the akenes as they mature.
B. FI. species 5 (Argentina).
1.	P. arguta Pursh. Upright Cinquefoil. An erect, stout, hairy
plant, 1--1 ft. high. Basal leaves long-petioled, pinnate. Stem leaves
few, each of 3-7 leaflets, the latter broadly ovate and cut-toothed or
serrate, downy underneath. Flowers large, in dense terminal clus-
ters ; the petals whitish or cream color. Rocky hills.
2.	P. monspeliensis L. Rough Cinquefoil. Annual or biennial.
Stem rough-hairy, erect and stout, 6-30 in. high. Leaves of 3 leaf-
lets, the lower petioled, the upper stem leaves sessile or nearly so,120
KEY AMD FLORA
leaflets cut-serrate. Flowers small, in a close, leafy cyme. Styles
glandular-thickened at the base. In dry soil.
3.	P. rivalis Nutt., var. millegrana. Diffuse Cinquefoil. Annual.
Stems decumbent or ascending, commonly diffusely branched, lj-3
ft. high, clothed with long, soft hairs or nearly smooth. Leaves all
but the uppermost of 3 leaflets and petioled; leaflets oblong, wedge-
shaped, thin, deeply serrate. Flowers yellow, in loose, leafy cymes.
Style somewhat thickened below. In damp soil W.
4.	P. argentea L. Silvery Cinquefoil. Stems prostrate or
ascending and branching, woolly. Leaflets oblong, wedge-shaped,
those of the upper leaves very narrow, with a few large, deeply cut
teeth, smooth and green above, silvery beneath, with a dense coat
of white wool. Flowers small and somewhat clustered, yellow. Dry
fields and roadsides.
5.	P. Anserina L. Silverweed. Stems spreading by slender
runners, with many joints, silky-hairy. Leaves all basal, pinnate;
leaflets 7-21, serrate, oblanceolate or obovate, nearly smooth above,
white and silky-downy beneath. Flowers yellow, 1—1 in. in diameter.
Style thread-like. River banks, brackish marshes, and borders of lakes.
6.	P. canadensis L. Common Cinquefoil. Stems slender, pro-
cumbent, silky-hairy, sending out long runners. Leaflets obovate,
wedge-shaped, appearing like 5 from the divisions of the 2 lateral
ones. Peduncles 1-flowered in the axils of the leaves. Flowers
yellow. Common in dry pastures and a troublesome wrned.
X. FILIPENDULA Hill. (ULMARIA)
Tall perennial herbs. Leaves pinnately divided, with
stipules. Flowers small, bisexual, in panicled cymes. Calyx
5-lobed. Petals 5, with claws. Stamens many, hypogynous,
borne on a flat or slightly hollowed receptacle. Pistils 5-15,
distinct. Carpels when ripe 1-2-seeded, looking like follicles
but not splitting open.
1.	F. rubra Hill. Queen of the Prairie. Smooth, branching,
2-8 ft. high. Leaves very large, of 3-7 pinnately arranged leaflets,
often with smaller ones between, the lobes cut or toothed ; terminal
leaflet much larger, 7-9-parted. Flowers showy, pink, fragrant,
about j in. in diameter. Meadows and prairies, especially in moist
soil, sometimes cultivated.
2.	F. Ulmaria Maxim. Meadowsweet. Stem 1-3 ft. high.
Leaves lvrate, interruptedly pinnate, white-downy beneath. Flowers
yellowish-white, small, fragrant, in a dense compound cyme. Pods
spirally twisted. Cultivated from Europe and sometimes escaping.ROSE FAMILY
121
XI.	GEUM L.
Erect perennial herbs. Basal leaves crowded, pinnate, with
a very large terminal leaflet. Flowers and fruit much as in
Potent “41*1 but the akenes tailed with the remains of the styles.
B. FI. species 5 (Sieversia).
1.	G. canadense Jacq. White Avexs. Stem erect, branching
above, smooth or finely downy, 18-41*1 in. high. Basifl. leaves pin-
nule, or the earliest simple and rounded, long-petioled, serrate or.
dentate; terminal lobe larger than the lateral lobes; stem leaves
short-petioled, 2-d-lobed or -parted. Flowers on slender peduncles.
Petals white, not longer than the sepals. Styles jointed near the
middle, the lower portion persistent and hooked. Ovaries and recep-
tacle hairy; head of fruit globose. Rich woods.*
2.	G. virginianum. L. Stem 2-3 ft. high, stout and bristly-hairy.
Lower leaves and basal leaves pinnate, varying greatly; upper leaves
mostly of 3 leaflets or 3-parted. Petals white or pale yellow', small,
shorter than the calyx lobes. Heads of fruit large, on stout, hairy
peduncles j, the receptacle nearly or quite smooth. Borders of w oods
and damp thickets.
3.	G. macrophyllum Willd. Large-Leaved Avexs. Stem stout,
erect, bristly-hairy, 1-3 ft. high. Basal leaves lyrate-pinnate, the
terminal portion much the largest, kidney-shaped or heart-shaped;
lateral leaflets 3-6, with smaller ones between. Flowers terminal,
yellow. Style {-) in. long, dow'ny below. In low' grounds.
4.	G. rivale L. Water Avexs, Purple Avexs, Chocolate
Root. Stem 14-2 ft. high, somewhat downy or hairy, simple or
nearly so. Basal leaves lyrate and somewhat pinnate, with the divi-
sions irregular ; stem leaves few', of 3 leaflets or 3-lobed. Flowers
rather large. Petals purplish-yellow, as long as the brownish-purple
calyx lobes. _Styles long, purplish; stigmas thread-like, feathered
with soft hairs, especially in fruit. Wet meadows.
5.	G. triflorum Pursh. Loxg-Plumed Purple Avexs. Softly
downy, scapes 6-13 in. high. Basal leaves petioled, tufted, pinnate;
the larger leaflets obovate or oval, cut-toothed, with many smaller
ones between. Flowers 3-8, light purple. Styles 1-1—2 in. long. In
dry or rocky soil.
XII.	RUBUS L.
Mostly prickly shrubs, producing runners. Leaves alternate,
simple or compound; stipules united to the petiole. Flowers in
terminal and axillary clusters, rarely solitary, white (in one
American species (iSTo. S) purple rose color). Calyx hypogynous,122
KEY AXD FLORA
with a broad tube ; its lobes 5, persistent. Petals 5. Stamens
many. Carpels many, distinct, on a convex receptacle. Fruit
a cluster of little 1-seeded drupes on a dry or somewhat juicy
receptacle.
A.	Raspberries
Grains of the fruit, when ripe, usually falling off from the receptacle
and leaning the latter with the calyx.
1.	R. idceus L., var. aculeatissimus. Red Raspberry. Stems
widely branching, biennial, not rooting at the tips, armed with
weak bristles and with a few hooked prickles. Leaves petioled, of
3-5 ovate leaflets which are sharply serrate and sometimes lobed,
downy beneath. Flowers in terminal and axillary racemes and
panicles, pedicels drooping. Fruit hemispherical or conical, red,
separating easily from the receptacle. Common on mountains and
burned clearings, Iowa and X., and widely cultivated.*
2.	R. occidentalis L. Black Raspberry'. Stems long and slender,
often recurved and rooting at the tips, armed with weak, hooked
prickles. Leaves petioled, 3-5 ovate leaflets, coarsely serrate, white-
downy below. Flowers white, in compact terminal corymbs. Pedi-
cels erect or ascending. Fruit black, hemispherical, separating easily
from the receptacle. Common on borders of woods, Missouri and
X., widely cultivated.*
3.	R. odoratus L. Flowering Raspberry (often wrongly called
Mulberry). Stems shrubby, rather stout, 3-5 ft. high, not prickly:
the young shoots, peduncles, and calyx covered with sticky glandular
hairs. Leaves large, simple, 3-5-lobed. Flowers showy, rose-purple,
1-2 in. in diameter, on many-flowered peduncles. Fruit red, flattisli,
eatable. Rather common E. and N., and often cultivated.
4.	R. triflorus Richards. Dwarf Raspberry (also wrongly known
as Mulberry'). A slender, trailing plant, almost entirely herbaceous,
not prickly but sometimes bristly. Leaves compound, usually of 3
but sometimes of 5 thin, ovate-lanceolate, frequently unsymmetrical
leaflets, which are coarsely doubly serrate and often cleft or lobed.
with a shining upper surface. Flowers small, on 1-3-flowered pedun-
cles. Fruit usually few-grained, rather dark red, eatable, the grains
adhering somewhat to the receptacle. Common, especially X., in hilly
woods, often forming a dense carpet in the partial shade of pines.
B.	Blackberries
Grains of the ripe fruit falling from the calyx along with the so ft, eat-
able receptacle.
5.	R. allegheniensis Porter. High Blackberry'. Stem shrubby,
erector bending, 3-7 ft. high, glandular-downy above and with stout,ROSE FAMILY
123
straightish prickles below. Leaves petioled, of 3-7 ovate leaflets which
are acute, irregularly serrate, soft-hairy beneath. Flowers racemed,
the lower ones leafy-bracted. Petals white, obovate, much longer
than the taper-pointed sepals. Fruit long, of small drupelets. Common
in thickets.*
6.	R. cuneifolius Pursh. Sand Blackberry. Stem shrubby,
erect or diffuse, 2-3 ft. high ; prickles straight or recurved. Leaves
petioled, 3-5-foliate ; leaflets obovate, serrate towards the apex,
■wedge-shaped towards the base, rough above, white downy-woolly
beneath. Racemes mainly terminal, few-flowered. Petals white,
longer than the sepals. Fruit ovoid, black, smaller than the preced-
ing. Common in old fields.*
7.	R. hispidus L. Running Swamp Blackberry. Stem trailing
or prostrate, often several feet in length, armed with recurved
prickles. Leaves petioled, mostly of 3 leaflets; leaflets obovate,
obtuse, thick, dark green and shining above. Flowering branches
commonly erect, few-flow'ered, flowers white. Fruit small, reddish,
turning nearly black. In swamps and low' ground.
8.	R. villosus Ait. Low Blackberry, Dewberry. Stems
shrubby, trailing widely, 3-10 ft. long, somewhat prickly. Leaflets
usually 3, but sometimes 5 or 7, ovate, acute, sharply (and doubly)
cuteserrate, thin. Racemes upright on the short branches. 1-3-flow-
ered. FYuit roundish, of fewer and larger grains than Xo. 5, very
sweet when fully ripe. Common X., in stony or gravelly fields.
XIII. ROSA L.
Erect running or climbing prickly shrubs. Leaves pinnate,
leaflets serrate, stipules united to the petiole. Calyx tube urn-
shaped, with a rather narrow mouth. Petals (in single roses) 5.
Stamens many, inserted around the inside of the mouth of the
calyx tube. Ovaries many, hairy, ripening into bony akenes,
inclosed in the rather fleshy and sometimes eatable calyx tube.
1.	R. pratincola Greene. Stems densely prickly, 1-2 ft. high.
Stipules narrow, usually with glandular teeth or a fringe of glandu-
lar hairs toward the tip; leaflets 7-11, varying from elliptical to
nearly obovate, obtuse at the tip, narrowed at the base, simply
toothed or serrate, rather firm and distinctly veined. Flowers usually
in corymbs ; sepals lanceolate, taper-pointed. Fruit globose, smooth.
Prairies, especially W.
2.	R. blanda Ait. Early Wild Rose. Stems 1-3 ft. high, usually
without prickles; stipules broad. Flowers generally large, corymbed
or solitary; sepals after flowering closing over the mouth of the calyx
tube and persistent. Rocks and rocky shores.124
KEY AND FLORA
3.	R. Woodsii Lindl. Stems 3-36 in. high, with slender spines which
are often wanting above. Stipules rather broad, entire; leaflets usu-
ally 5-7, varying from obovate to lanceolate, rather obtuse at the apex,
narrowed at the base, somewhat serrate. Flowers corymbed or solitary.
Sepals erect on the globose or somewhat ovoid fruit. Prairies W.
4.	R. rubiginosa L. Sweetbrier. Stem erect or curving, armed
with stout recurved prickles. Leaves with 5-7 leaflets, the latter
broadly oval, coarsely serrate, glandular-bristly beneath, aromatic.
Flowers white or pink. Sepals widely spreading, deciduous. Fruit
obovate, slightly bristly. Common in cultivation and sometimes wild.*
5.	R. Carolina L. Swamp Rose. Stems 4-8 ft. high, with stout
and generally recurved prickles. Stipules long and narrow ; leaflets
commonly downy beneath, finely serrate. Flowers several in a corymb,
bright rose color. Sepals spreading and falling off after flowering.
Damp woods and borders of swamps.
6.	R. virginiana Mill. Dwarf Wild Rose. Stems varying in
height from less than a foot to 6 ft., with stout, somewhat hooked
prickles. Stipules rather broad; leaflets small, thiekish and glossy
above, coarsely toothed toward the tip. Flowers corymbed or soli-
tary, pale rose color. Sepals spreading and falling off after flowering.
Moist ground and swamps.
7.	R. humilis Marsh. Pasture Rose. Stem erect, branched,
usually armed with stout stipular prickles and with bristles, but
sometimes nearly smooth, 1-3 ft. tall. Leaves mostly of 5 leaflets;
stipules entire; leaflets oblong-lanceolate or oval, shining above,
pale beneath, sharply serrate. Flowers solitary or 2-3 together,
2-3 in. broad, pink. Peduncles and calyx glandular-downy. Sepals
leaf-like, spreading, finally deciduous. Styles distinct. Fruit globose,
bristly-hairy. On dry soil; our most common wild rose. S.*
XIV. PRUNUS L.
Trees or shrubs. Leaves simple, with stipules, which are
often small or fall off early. Calyx with a bell-shaped or urn-
shaped tube and 5-lobed spreading limb, falling off after flower-
ing. Petals 5; stamens 3-5 times as numerous, or indefinite,
inserted on the throat of the calyx tube. Pistil 1, long-styled,
with 2 ovules, ripening into a single drupe.
B. FI. species 8 (Amyr/dalus).
A. Stone more or less spherical; fruit smooth when ripe■ Branches
not spiny. (Cherries.)
1. P. serotina Ehrh. Wild Black Cherry. Often becoming a
large tree; bark on old trees rough, nearly black. Leaves ratherROSE FAMILY
125
thick, oval to lanceolate-ovate, acute or taper-pointed at the apex,
finely serrate with calloused teeth, smooth above, downy on the veins
beneath. Racemes terminal, long and spreading. Flowers white.
Fruit globose, about i in. in diameter, purplish-black. In rich woods.
Wood much used in cabinet-making.*
2.	P. yirginiana L. Chokeciiekky. A shrub or small tree, 5-20 ft.
high. Leaves thin, oval or obovate, pale, pointed, sharply serrate. Flow-
ers small, white, in short racemes. Fruit bright red, turning at length
to dark crimson, very puckery until fully ripe. River banks and thickets.
3.	P. pennsylvanica L. f. Wild Red Cherry. A tree 20-30 ft.
high, with light, reddish-brown bark. Leaves oval or oblong-lanceo-
late, pointed, finely serrate, with both sides green, smooth and shin-
ing. Flowers long-pediceled, many in a cluster, the clusters lateral,
leafless. Fruit globose, very small, light red, with thin sour pulp
and globular stone. In rocky woods.
4.	P. Besseyi Bailey. Western Sand Cherry. A shrub 1-4 ft.
high, often with spreading and prostrate branches. Leaves usually
elliptic or oblong-elliptic, with appressed teeth. Flowers sessile in
lateral umbels, | in. to nearly in. in diameter, opening with the
leaves. Fruit black, mottled, or yellowish, -I—f in. in diameter, bitter
and astringent, Prairies W.
5.	P. Cerasus L. Cherry. Often becoming a large tree. Leaves
oval or ovate, acute or taper-pointed at the apex, rounded at the
base, irregularly serrate-dentate, smooth on both sides, resinous
when young. Flowers in lateral umbels, white ; pedicels long and
slender. Fruit globose, red or black. Cultivated from Europe. This
is the species from which most of our sour cultivated varieties have
been developed.*
B. Stone oeal, compressed: fruit smooth when ripe. Branches often
spin;/. (Plums.)
6.	P. angustifolia Marsh. Chickasaw Plum. A small tree with
spiny branches. Leaves lanceolate or oblong-lanceolate, acute at the
apex, usually obtuse at the base, finely and sharply serrate, rather
thin, smooth. Flowers in lateral, sessile umbels, pedicels short.
Calyx smooth. Fruit yellowish-red, subglobose, skin thin, stone only
slightly compressed. In old fields S.*
7.	P. americana Marsh. Wild Plum. A small tree, bark thick
and rough, branches spiny. Leaves ovate or obovate, acuminate at
the apex, rounded or cordate at the base, sharply serrate, rather
thick, downy beneath ; petioles glandular. Flowers in lateral, sessile
umbels, appearing with or before the leaves; pedicels i-J in- long,
flowers in. in diameter. Calyx downy within. Fruit globose, red
or yellow, |-1 in. in diameter. Common in woods.*126
KEY AND FLORA
C. Stone deeply furrowed and pitied; fruit downy when ripe. Branches
not spiny. (Peaches and almonds.)
8. P. persica Stokes. Peach. A tree with a rounded top; bark
nearly smooth. Leaves lanceolate, taper-pointed, finely serrate, smooth
on both sides; petioles usually bearing 2 or 4 crescent-shaped or cup-
shaped glands. Flowers pink, scaly-bracted. Fruit ovoid, with a
seam along one side. Often escaped from cultivation.*
Herbs, shrubs, or trees. Leaves alternate, usually com-
pound (either pinnately or palmately), with stipules, the
leaflets mostly entire. Calyx of 5 sepals, which are more or
less united, often somewhat zygomorphic. Corolla of 5 petals,
Fig. 20. Pulse Family
A, actinomorphic corolla (Acacia cinerascens): 11, zygomorphic corolla
(Cassia murilandica). (After Sclinizlein)
often papilionaceous (Fig. 21) or somewhat actinomorphic, in
No. XVI much reduced. Stamens diadelphous (Fig, 22), mon-
adelplious, or distinct. Ovary simple, superior. Fruit usually
a 1-celled pod (Fig. 22). Seeds one or several, without endo-
sperm. A large and very important family, containing about
8000 species.
47. LEGUMINOS.®. Pulse FamilyPULSE FAMILY
127
A
Flower actinomorphic, small. Stamens hypogynous. Lenres twice pinnate.
Petals not united to each other. Stamens 5 or 10. Pod smooth.
Desmanthus, I
Corolla gamopetalous, 5-cleft. Stamens 8 or 10. Pod minutely
prickly or rough.	Schrankia, II
Trees. Flowers somewhat or not at all papilionaceous, sometimes almost
actinomorphic. The upper petal inside the others in the bud. Stamens
10 or less, usually not united to each other, borne on the calyx.
Flowers imperfectly papilionaceous. Leaves simple. C'ercis, V
Flowers not papilionaceous. Thornless.	Gymnoeladus, III
Flowers not papilionaceous. Thorny.	Gleditsia, IV
A, stamens and pistil of sweet pea (magnified); B, fruit; C, part of fruit,
showing one seed128
KEY AND FLORA
C
Herbs or trees. Flowers decidedly papilionaceous. The upper petal ex-
ternal in bud and inclosing the others. Stamens 10, not united to each
other.
Trees.	Cladrastis, YII
Herbs. Pod inflated.	Baptisia, VI
Herbs. Pod elongated, necklace-shaped.	Sophora, VIII
D
Shrubs with a corolla of one petal only.	Amorpha, XVI
E
Herbs, shrubs, or trees. Flowers decidedly papilionaceous. Stamens
monadelplious or diadelphous (in the latter case usually 9 and 1).
1.	Stamens with anthers of two forms.
(a)	Herbs. Leaves usually with many leaflets. Lupinus, IX
(5) Herbs. Leaves with 3 entire leaflets. Psoralea, XV
(c) Trees.	Laburnum, X
(rf) Low shrubs.	Cytisus, XI
2.	Anthers all alike. Leaves usually with 3 leaflets.
(u) Pod coiled.	lUedieago, XIV
(b)	Pod small, not coiled. Flowers in racemes.
Melilotus, XIII
(c)	Pod small, not coiled. Flowers in heads. Trifolium, XII
(d)	Pod large, flattened, bur-like.	Desmodium, XX
(e)	Pod large, not much flattened.	Phaseolus, XXIV
Anthers all alike. Leaves odd-pinnate, with more than 3
leaflets.
(a)	Low, woody shrubs.	Amorpha, XVI
(b)	Tall, twining shrubs.	Wisteria, XVIII
(c) Trees.	Robinia, XVII
(d) Herbs.	Astragalus, XIX
4. Anthers all alike. Leaves pinnate, the midrib prolonged into
a tendril.PULSE FAMILY
129
(а)	Leaflets usually many pairs. Style slender, bearded only
at the tip or all round the upper portion. Pod 2-
several-seeded.	Yicia, XXI
(б)	Leaflets few or several pairs. Style bearded along one
face only. Pod several-seeded.	Lathyrus, XXII
(c) Leaflets 1-3 pairs. Style enlarged above, grooved on
the back. Pod several-seeded; seeds large, globular or
nearly so.	Pisum, XXIII
I.	DESMANTHUS TVilld. (ACUAN)
Shrubs or perennial herbs. Stems erect or diffuse, smooth.
Leaves abruptly t\vice-pinnate; stipules small. Flowers m
heads or spikes, on axillary peduncles, the upper bisexual, the
lower often staminate or neutral. Calyx 5-tootbed. Corolla of
5 distinct petals or 5-cleft. Stamens 5-10, distinct. Ovary
nearly sessile, flat, several-seeded.*
1. D. illinoensis Mac M. Desmaxtiuts. Stem erect or ascend-
ing, smooth, 1—1 ft. high. Pinnse 6-11 pairs, each with a minute
gland at the base; leaflets 20-30 pairs, small, linear. Heads globose.
Stamens o. Pods several, on a, peduncle 2-3 in. long, curved, flat,
2-valved, 3-6-seeded. Open, sandy fields.*
II.	SCHRANKIA Willd. (MORONGIA)
Perennial herbs. Stems reclining or prostrate, prickly, 2-5
ft. long. Leaves twice-pinnate; stipules bristly. Flowers bi-
sexual or somewhat monoecious, in axillary peduncled heads.
Calyx minute. Corolla tubular, 5-cleft. Stamens 8-10, dis-
tinct. Pod long, prickly, 1-celled.*
1. S. uncinata YTilld. Sensitive Brier, Sensitive Rose, Sh\me
Vine. Plant covered w ith hooked prickles. Leaflets elliptical, w ith
a conspicuous network of veius beneath; leaves closing gradually
after being touched. Flow»ers rose-colored. Pods nearly cylindrical,
2 in. long. Dry, sandy soil and rolling prairies, especially S. and W.
m. GYMNOCLADUS Lam.
A large, thornless tree, its twigs few and stout. Leaves very
large, twice pinnately compound, without stipules. Flowers
actinomorphic, whitish, dioecious or somewhat monoecious, in130
KEY AND FLORA
racemes at the ends of the branches. Calyx tube rather long,
its 5 lobes spreading. Petals oblong, all alike, inserted with
the stamens on the throat of the calyx. Stamens of the fertile
flowers usually not pollen-bearing. Pod hard, flat, partly filled
with a sweet substance, slow in opening. Seeds several, flattish,
over i in. in diameter, very hard and shining.
1. G. dioica Koch. Kentucky Coffee Tree. Tree 50 ft. or more
in height, with rough gray bark. Leaves 2—1 ft. long, the leaflets
vertical. Pods sometimes nearly 1 ft. long. Rich soil and river bot-
toms, especially S. and W.
IV. GLEDITSIA L.
Large trees; bark dark-colored, nearly smooth. Leaves
usually pinnately twice compound; leaflets serrate. Flowers
somewhat monoecious, in small spike-like racemes. Calyx
spreading, 3-5-cleft. Petals as many as the sepals and in-
serted at the summit of the tube. Stamens 5-10, distinct,
inserted with the petals. Ovary nearly sessile, ovoid or
elongated. Fruit a 1-or many-seeded, leathery pod.*
1. G. triacanthos L. Honey Locust. A large tree, usually armed
with stout, branched thorns, which are sometimes a foot or more in
length. Leaves petioled; leaflets short-stalked, lanceolate-oblong,
base inequilateral, smooth above, often downy below. Racemes soli-
tary or in small clusters, drooping. Flowers inconspicuous, greenish.
Pod linear-oblong, often 12-15 in. long by 1 in. wide, twisted, many-
seeded, smooth and shiny, pulpy within. In rich woods.
V. CERCIS L.
Trees. Leaves simple, with stipules. Flowers in axillary clus-
ters, somewhat papilionaceous. Calyx bell-shaped, 5-toothed.
Stamens 10, distinct. Ovary short-stalked; ovules several.
Fruit a flattened pod.
1. C. canadensis I.. Redbud. A small tree. 10-20 ft. high; wood
hard but weak; bark smooth, dark-colored. Leaves broadly cordate,
abruptly acute, rather thick, very smooth above, often slightly downy
below. Flowers several in a cluster, appearing before the .leaves,
pinkish-purple. Pod oblong, compressed, many-seeded. Common on
rich soil, especially S.*PULSE FAMILY
131
VI. BAPTISIA Vent.
Perennial herbs ; stems erect, widely branched. Leaves
simple or palmate, of 8 leaflets. Flowers in racemes. Calyx
4-5-lobed, persistent, the upper lobe usually longer and
notched; standard rounded, its sides reflexed, wings about
as long as the keel. Stamens 10, distinct. Pod stalked, long-
pointed by the remains of the style. Plants usually becom-
ing black in drying.*
1.	B. tinctoria R. Br. Wild Indigo. Stem smooth, slender, 2-4 ft.
high; branches slender. Leaves of 3 leaflets, on short petioles, the
upper nearly sessile; stipules minute, quickly deciduous. Leaflets
obovate to oblanceolate, obtuse at the apex, wedge-shaped at the base,
entire. Itacernes numerous, terminal. Flowers yellow,-1 in. long. Pod
globose, ovoid, on a stalk about the length of the calyx, point long and
slender. Plant blackening in drying. Common on dry, sandy soil.*
2.	B. bracteata Muhl. Low, hairy, and branching. Leaves nearly
sessile ; leaflets oblanceolate or obovate-spatulate ; stipules triangular-
ovate, large, persistent; bracts large and leaf-like. Racemes long.
Flowers large, yellowish-white. Pod ovoid, swollen. Prairies and
open woods W. and S.
3.	B. leucantha T. & G. Stout, smooth, and covered with a bloom,
3 ft. or more high, with spreading branches. Petioles short ; lanceo-
late stipules and bracts falling off early. Racemes erect. Flowers
large, white. Pods ellipsoidal, 2 in. long, borne on a stalk twice as
long as the calyx. Rich river bottoms and prairies.
4.	B. alba R. Br. White Wild Ixdigo. Stem smooth and with a
bloom, often purple, 2-3 ft, high; branches slender, spreading. Leaves
petioled, with 3 leaflets; stipules minute, soon deciduous. Flowers
white, mostly in a single raceme which is 1-3 ft. long, with occasionally
lateral, few-flowered racemes. Pod linear-oblong, the point very slen-
der and soon deciduous. Plant unchanged in drying. In damp soil.*
5.	B. australis R. Br. Blue False Indigo. Stem smooth, stout,
2-4 ft. high. Leaves of 3 leaflets, short-petioled; stipules lanceolate,
persistent, longer than the petioles; leaflets oblong, wedge-shaped or
narrowly obovate, entire. Flowers bright blue, 1 in. long, in terminal,
erect, loosely flowered racemes; stalk about the length of the calyx.
Pod oblong, with a slender, persistent point. Banks of rivers ; often culti-
vated for ornament.*
Vn. CLADRASTIS Eaf.
A moderate-sized, tree, with smooth dark gray bark and
yellow wood. Leaves of 7-11 smooth oval or ovate leaflets.132
KEY AND FLORA
Flowers creamy-white, in long, drooping panicles. Calyx 5-
tootked. Standard large, nearly round, reflexed; petals of the
keel and wings separate and straight. Stamens 10, uncon-
nected with each other. Pod borne on a short stalk above the
calyx. Seeds 4-6.
1. C. lutea Koch. Yellow Wood. Tree 50 ft. or less in height,
much branched, with a round, spreading top. Hillsides, in fertile
soil, south central states. Also considerably planted as a shade tree.
VIII.	SOPHORA L.
Shrubby or herbaceous perennials. Leaves odd-pinnate, with
many leaflets. Calyx bell-shaped, with 5 short teeth. Standard
roundish ; keel nearly straight. Stamens almost or quite dis-
tinct ; anthers versatile. Pod stalked, leathery or fleshy, nearly
cylindrical but more or less contracted between the seeds, not
splitting open.
1. S. sericea Nutt. Herbaceous with a woody base, erect. 6-12
in. high, covered with silky silvery down. Leaflets 7-25, obovate or
nearly so, obtuse, narrowed at the base, J in. long. Flowers white.
Pod slender, dry, few-seeded. Prairies W. and S.W.
IX.	LUPINUS L.
Biennial or perennial herbs. Leaves simple or palmately
compound. Flowers showy, in terminal racemes. Calyx
2-	lipped, 5-toothed. Standard round, with the sides reflexed;
keel scythe-shaped. Stamens moriadelphous; anthers alter-
nately oblong and roundish. Ovary sessile; matured pod
oblong, several-seeded, often compressed between the seeds.*
1. L. perennis I,. Perennial. Stem erect, downy, 12-18 in. high.
Leaves palmately 7-9-foliate ; leaflets obovate or oblanceolate, obtuse
and mucrnnate at the apex, slightly downy ; petiole slender; stipules
small. Racemes terminal, slender, loosely many-flowered. Flowers
purple, blue, pink, or white. Pod oblong, densely downy, few-seeded.
Dry, sandy soil.*
X. LABURNUM Medic.
Trees or shrubs. Leaves of 3 leaflets, with very small
stipules or none. Flowers golden-yellow, in slender, drooping
racemes. Calyx 2-lipped, the upper lip 2-toothed, the lower
3-	toothed. Standard ovate, upright, of the same length as thePULSE FAMILY
133
straight wings. Stamens diadelphous (9 and 1). Ovary and
pod somewhat stalked above the calyx, several-seeded.
1. L. vulgare Griseb. Laburnum, Golden Chain. A small tree,
with smooth, greenish bark. Leaves with slender petioles; leaflets
oblong-ovate, acute at the base, taper-pointed, downy beneath.
Flowers showy, in graceful racemes. Cultivated from Europe.
XI. CYTISUS L.
Shrubs, rarely spiny. Leaves of 1-3 leaflets or none; stipules
very small. Calyx 2-lipped, the upper lip slightly 2-toothed,
the lower 3-toothed. Keel straight or a little curved, blunt,
turned down after flowering. Stamens with their filaments
all united; anthers every other one short and attached by its
center, the alternate ones long and fastened by their bases.
Style curved in, or, after the flower opens, coiled up. Pod
flat, long, many-seeded.
1. C. canariensis Dumont. A shrub with many rather stiff, erect,
slender branches. Leaves abundant, very small, covered with soft
gray hairs; leaflets 3, obovate. Flowers rather small, yellow, in
somewhat erect racemes. Cultivated in greenhouses. From the
Canary Islands.
XII. TRIFOLIUM L.
Annual, biennial, or perennial herbs. Stems more or less
spreading. Leaves petioled, of 3 toothed or serrate leaflets;
stipules united to the petioles. Flowers white, yellow, or red,
in heads. Calyx 5-cleft, the teeth nearly equal, awl-shaped.
Petals withering-persistent; keel shorter than the wings. Sta-
mens diadelphous. Pod smooth, 1-6-seeded, scarcely opening.*
1.	T. arvense L. If abbit Foot Clover, Stone Clover. Annual,
silky-downy, erect, branching, 5-10 in. high. Leaflets oblanceolate or
linear, minutely toothed above. Heads terminal, peduncled. Calyx
teeth very silky-hairy, longer than the whitish corolla. Old fields, rail-
road embankments, and waste ground. Naturalized from Europe.
2.	T. incarnatum L. Crimson Clover. Annual. Stem erect,
somewhat branched, downy, 1-2 ft. high. Lower leaves long-petioled,
the upper short-petioled ; leaflets obovate or wedge-shaped, toothed at
the apex. Flowers bright crimson, sessile, in terminal heads which
finally become much elongated. Calyx silky, its lobes long and
plumose. Introduced from Europe and cultivated for fodder.134
KEY AND FLORA
3.	T. pratense L. Red Clover. Biennial or short-lived peren-
nial. Sterns spreading, branching, downy, 1-3 ft. long. Leaves long-
petioled; stipules large; leaflets oval to obovate, finely toothed, often
with a dark triangular spot near the center. Flowers red or purple,
in globose heads, erect in fruit. Calyx teeth bristle-shaped, hairy.
Pod 1-3-seeded. Introduced from Europe and widely cultivated.*
4.	T. repens L. White Clover. Perennial. Steins widely branch-
ing at the base, prostrate and creeping, nearly smooth, 6-12 in.
long. Leaves long-petioled; leaflets oval, obovate, or obcordate,
minutely toothed. Heads globose, long-peduncled. Flowers white,
reflexed in fruit. Pod 3-4-seeded. Common about houses and in
pastures.*
5.	T. hybridum L. Alsike Clover. Perennial, considerably
resembling No. 4, but the stems more upright and stouter. Leaflets
varying from broadly ovate to ovate-lanceolate, mucronate or slightly
notched, the margins fringed with hairs; stipules prolonged into
bristle-like points. Flowers rose color and white, very fragrant. In
fields and along roadsides. Introduced from Europe.
6.	T. carolinianum Hichx. Carolina Clover. Perennial. Stems
spreading or ascending, much-branched, downy, 6-10 in. long. Leaves
short-petioled; leaflets small, obovate or obcordate, slightly toothed.
Heads small, globose, on long peduncles. Flowers white, tinged
with purple, reflexed in fruit. Pod 4-seeded. Common in waste
places 8.*
7.	T. procumbens L. Low Hop Clover. Annual. Stem slender,
erect or spreading, downy, 6-10 in. long. Leaves short-petioled;
leaflets obovate or obcordate, finely dentate, the middle one distinctly
stalked; stipules lance-ovate. Flowers yellow, reflexed in fruit. Pod
1-seeded. Common on clay soil, in waste places. Naturalized from
Europe.*
XIII. MELILOTUS Hill.
Annual or biennial herbs. Leaves petioled, of 3 leaflets.
Flowers small, white or yellow, in dense axillary and terminal
racemes. Calyx 5-toothed, the teeth nearly equal. Standard
erect, wings and keel cohering. Stamens 10, diadelphous.
Pod longer than the calyx, 1-4-seeded.*
1. M. alba Lam. Melilotus. Biennial. Stem erect, branching,
smooth or the young branches slightly downy. Leaflets oblong or
oblanceolate, rounded or truncate at the apex, serrate; stipules small.
Racemes long, slender, erect. Flowers white. Standard longer than
the wings and keel. Pod ovoid, wrinkled, drooping, mostly 1-seeded,
scarcely opening. Common as a weed and widely cultivated.*PULSE FAMILY
135
2. M. officinalis Willd. Yellow Sweet Clover. A stout, upright,
branching herb, 2-4 ft. high, looking much like the preceding species,
but coarser. Flowers yellow. Waste ground and roadsides. Natu-
ralized from Europe.
XIV.	MEDICAGO L.
Annual or perennial herbs. Leaves petioled, of 3 toothed
leaflets. Flowers in terminal and axillary spikes or racemes.
Calyx 5-toothed, the teeth short and slender. Standard
oblong, much longer than the wings or keel. Stamens 10,
diadelphous. Ovary sessile. Pod 1-several-seeded, coiled,
not splitting open, often spiny.*
1.	M. sativa L. Alfalfa. Perennial. Stems erect, branching,
downy when young, becoming smooth with age, 2-3 ft. high. Leaves
short-petioled; leaflets obovate, sharply dentate towards the apex,
obtuse or sometimes notched or mucronate; stipules lanceolate, entire.
Flowers blue, small, in rather close spikes. Pods downy, coiled, few-
seeded. Introduced from Europe, and cultivated for hay and pasture.*
2.	M. lupulina L. Black Medick, Nonesuch. An annual or
biennial, much-branched, reclining herb, with stems 6-20 in. long.
Leaves very short-petioled; leaflets obovate, acute, J-J in.long, toothed
near the tip. Flowers small, yellow, in short spikes. Pods very small,
1-	seeded, kidney-shaped, black. Roadsides and waste ground, adven-
tive from Europe.
XV.	PSORALEA L.
Perennial herbs; whole plant glandular-dotted. Leaves of
3-5 leaflets ; stipules united with the petioles. Flowers in axil-
lary or terminal spikes or racemes. Calyx 5-cleft, the lobes
nearly equal. Standard ovate or orbicular; keel incurved,
obtuse. Stamens monadelphous or diadelphous, 5 of the anthers
often undeveloped. Ovary nearly sessile. Pod included in the
calyx, often wrinkled, remaining closed, 1-seeded.*
1.	P. pedunculata Vail. Samson’s Snake root. Stem erect, slen-
der, branching above, downy, 1-2 ft. high. Leaves of 3 leaflets;
petioles shorter than the leaflets; stipules awl-shaped; leaflets ellip-
tical or oblong-lanceolate, sparingly glandular-dotted, the terminal
one stalked. Loosely flowered spikes axillary and terminal, on pedun-
cles much longer than the leaves. Flowers blue or purple, about | in.
long. Pod compressed-globose, wrinkled transversely. Dry soil.*
2.	P. tenuiflora Pursh. LTpright, slender, bushy and branching,
2-	4 ft. high, covered when young with a fine grayish down. Leaves136
KEY AND FLORA
palmately compound, with 3-5 linear to obovate-oblong leaflets, cov-
ered with glandular dots. Flowers in. long, loosely racemed.
Pod rough with glands. Prairies IV.
3.	P. argophylla Pursh. Silver-Leaved Psor ale a. Densely
silvery downy, with white, close-lying hairs. Stem often zigzag, 1-3
ft. high. Leaves palmate; leaflets 3-5, elliptical-lanceolate, oval or
obovate. Spikes interrupted, the peduncles longer than the leaves.
Flowers blue or purplish, j in. or more long. Pod ovate, beak straight.
Prairies, especially N.W.
4.	P.esculenta Pursh. Pom me Bl anche, Tipsin, Dakota Turnip.
Clothed with roughish hairs. Stem 5-15 in. high, erect and stout.
Root turnip-shaped, starchy, eatable. Leaves palmately compound,
with 5 lance-oblong leaflets. Flowers 1 in. long, in a dense ellipsoidal
spike. Pod hairy, with a pointed tip. High prairies or plains,
especially N.AV.
XVI.	AMORPHA L.
Small shrubs, glandular-dotted. Leaves odd-pinnate. Flowers
purple, blue, or white, in slender spikes or racemes. Calyx
5-toothed, persistent. Standard obovate, concave; ivings and
keel none. Stamens monadelphous, projecting much. Ovary
sessile. Pod curved, glandular-roughened, 1-2-seeded, never
opening.*
1.	A. canescens Pursh. Lead Plant, Shoe Strings. A bushy,
vrhite, silky-downy shrub, 1-3 ft. high. Leaflets small and crowded,
21-49, oral or oblong-elliptical. Spikes mostly clustered at the sum-
mit, rather showy. Standard bright blue, roundish. Pod 1-seeded,
slightly longer than the calyx. Prairies. Roots very long and tough,
hence one common name.
2.	A. microphylla Pursh. A bushy shrub about 1 ft. high. Leaves
many, short-]ictioled; leaflets 13-19, rigid, oval or oblong. Racemes
mostly solitary. Flowers fragrant; standard purplish. Prairies,
especially N.W.
3.	A. fruticosa L. False Indigo. A shrub, 6-15 ft. high, with
smooth, dark-brown bark. Leaves petioled ; leaflets 15—21, short-
stalked, oblong, obtuse or notched, sparingly punctate with clear dots.
Slender flowering spikes, panieled or solitary, 4-6 in. long. Flowers
blue or purple. Calyx teeth short, nearly equal, downy. Pod glandu-
lar. River banks.*
XVII.	ROBINIA L.
Trees or shrubs. Leaves odd-pinnate ; stipules often spiny.
Flowers showy, in axillary racemes. Calyx short, 5-toothed,PULSE FAMILY
137
the two upper teeth shorter and partially united. Standard
large, orbicular, reflexed, keel obtuse. Stamens diadelphous.
Style bearded on one side. Pod compressed, several-seeded.*
1. R. Pseudo-Acacia L. Black Locust. A tree of medium size;
bark rough and nearly black ; twigs and leaves smooth. Leaflets
9-15, ovate or oblong, obtuse and slightly mucronate at the apex;
stipules forming persistent spines. Racemes loose, pendulous, 3-5 in.
long'. Flowers white, fragrant. Pod smooth, 4-8-seeded. Introduced,
and quite common ; wood very durable when exposed to the weather,
and extensively used for posts.*
XVIII. WISTERIA Nutt. (BRADLEYA)
Tall, twining shrubs. Leaves odd-pinnate. Racemes ter-
minal. Flowers large and showy. Calyx 2-lipped, the upper
lip 2-cleft, short, the lower longer and 3-cleft. Standard
large, round, with 2 calloused ridges at the base ; wings eared
at the base; keel scythe-shaped. Pod long, stalked, leathery,
2-valved, several-seeded.*
1 W. frutescens Poir. Wisteria. Stem climbing 30-40 ft., often
2-3 in. in diameter at the base; branches and leaves downy when
young, becoming smoother with age. Leaves short-petioled ; stipules
minute; leaflets 9-17, ovate-lanceolate, acute at the apex, rounded
at the base. Racemes large, densely flowered. Calyx downy. Corolla
lilac-purple, wings with a short and a long appendage at the base.
Pod 2-3 in. long, 2-4-seeded. River banks S. Often cultivated for.
ornament..*
2. W. chinensis PC. Chinese Wisteria. Larger and faster
growing than No. 1. Racemes longer and more slender. Wing
appendage at one side only of base. Seldom fruiting in this region.
Cultivated from China or Japan.
XIX. ASTRAGALUS L.
Mostly perennial herbs. Leaves odd-pinnate. Flowers in
spikes or racemes. Calyx 5-toothed. Petals long, erect, with
claws. Standard narrow. Stamens diadelphous (9 and 1).
Pod usually swollen, sometimes fleshy and eatable, several-
many-seeded. [A large and very difficult genus; mostly of far
western species.]138
KEY AND FLORA
1.	A. caryocarpus Ker. Ground Plum, Buffalo Apple. Covered
with pale, close-lying down. Leaflets narrow, oblong'. Flowers violet-
purple, in a short, narrow raceme. Fruit looking like a small, green,
pointed plum, about § in. in diameter, eatable. N.W., and S. to
Texas.
2.	A. mexicanus A. I)C. Prairie Apple. Smooth or with some
loose hairs. Corolla cream color, with the tip bluish. Fruit globular,
not pointed, eatable. Prairies, Illinois and SAY.
3.	A. canadensis L. Erect, often tall (1-1 ft. high), more or less
downy. Leaflets oblong, 21-27. Flowers pale greenish, in long
spikes. Pod dry, 2-celled, sessile. River bottoms, prairies, and woods.
4.	A. parviflorus MacM. Erect and slender, finely downy, some-
what ash-color, 1-2 ft. high. Leaflets 11-21, linear, obtuse, distant.
Flowers purple, in. long, in long, slender racemes. Pods sessile,
\ in. or less in length, concave on the back, white-hairy, becoming
smooth. Prairies, especially NAV.
XX. DESMODIUM Desv. (MEIBOMIA)
Perennial herbs. Leaves pinnate, with stipules, usually
with leaflets. Flowers in axillary or terminal racemes, or
sometimes in panicles, usually purple, sometimes pink or
whitish. Calyx usualty somewhat 2-lipped. Standard ovate,
obovate, or roundish; wings attached to the straight or nearly
straight keel by a little appendage projecting from each side
of the keel. Stamens monadelphous (9 and 1) or all united at
their bases. Pod flat, its lower margin variously lobed, sepa-
rating into flat segments which are usually furnished with
short, strong, hooked hairs, making the fruit a troublesome
bur. [A large and rather difficult genus. Most of the species
can only be distinguished by the fruit, which matures in late
summer or autumn.]
XXI. VICIA L.
Climbing or spreading herbs. Leaves odd-pinnate, usually
ending in a tendril. Leaflets many, entire or toothed at the
tip; stipules half arrow-shaped. Flowers blue, purple, or yel-
low, in axillary racemes. Calyx teeth nearly equal. Wings
united to the keel. Stamens diadelphous (9 and 1); filaments
thread-shaped ; anthers all alike. Style bent, smooth or downy
all round or bearded below the stigma; ovules usually many.
Pod flattened, 2-several-seeded. Seeds globular.PULSE FAMILY
139
1.	V. sativa L. Commox Yf.tch. Annual. Stem simple, smooth,
reclining, 1-3 ft. long. Leaves short-petioled; leaflets 2-5 pairs,
obovate-oblong to linear, obtuse, notched and niucronate at the
apex. Flowers in pairs, nearly sessile in the axils, pale purple, in.
or less in length. Fod linear, several-seeded. In gravelly soil. Intro-
duced from Europe.
2.	V. caroliniana Walt. Perennial. Smooth or nearly so, 4-0 ft.
high. Leaflets 3-24, narrowly oblong, blunt. Peduncles loosely flow-
ered. Flowers small, whitish or tipped with pale purple. River banks.
3.	V. americana Muhl. Wild Vetcii, Buffalo Pea. Perennial.
Smooth, 1-3 ft. high. Leaflets 10-14, elliptical or ovate-oblong,
obtuse. Peduncles shorter than the leaves, 4-8-flowered. Flowers
bluish-purple, -J in. long. Common N. and W.
XXII. LATHYRUS L.
Like Vin'a, excepting that the leaflets are fewer and the
style is bearded on the side toward the standard.
1.	L. maritimus Bigelow. Beach Pea. Perennial. Stem stout,
1-2 ft. high. Stipules broadly ovate and heart- or halberd-shaped,
nearly as large as the 0-12 leaflets, of which the lower pair is the
largest; tendrils pretty large. Flowers large, blue or purple. Sea-
shores and beaches of the Great Lakes.
2.	L. palustris L. Wild Pea. Stem frequently winged, slender,
and climbing by delicate tendrils at the ends of the leaves. Stipules
narrow and pointed; leaflets 4-8, narrowly oblong to linear, acute.
Peduncles bearing 2-6 pretty large, drooping, blue, purple, and white
flowers. Damp thickets and borders of swamps.
3.	L. venosus Muhl. Veiny Vetch. Perennial. Stem stout,
prominently angled, climbing or reclining, 2-5 ft. long. Leaves
short-petioled; stipules lai-ge, lanceolate; leaflets 5-7 pairs, broadly
ovate-obtuse, mucronate. Peduncles nearly as long as the leaves,
many-flowered. Flowers purple, f in. long. Calyx teeth very unequal.
Pod linear, veined, 4-6-seeded. Shady banks and moist prairies.*
4.	L. odoratus L. Sweet Pea. Annual. Stem roughish-hairy,
it and the petioles winged. Leaflets only one pair, oval or oblong.
Flowers large, 2 or 3 on the long peduncles, sweet-scented, white,
rose color, purple, or variegated. Cultivated from Europe.
XXIII. PISUM L.
Climbing or prostrate herbs. Style enlarged above, grooved
on the back, with soft-hairy down on the inner edge. Leaflets
1-3 pairs. Flowers and fruit much like those of Lathyrus.140
KEY AND FLORA
1. P. sativum L. Common- Pea. Annual. Smooth and covered
with a bloom. Leaflets usually 2 pairs; tendrils branching; stipules
large, ovate, rather heart-shaped at the base. Peduncle several-flowered.
Flowers white, bluish, reddish, or variegated. Pods large; seeds glob-
ular or somewhat flattened and wrinkled. There are many varieties,
differing greatly in size, of the plant and of the fruit. Cultivated from
Europe (?).
XXIV. PHASEOLUS L.
Twining herbs. Leaves pinnate, of 3 leaflets. Flowers in
axillary racemes. Calyx 5-toothed, or 5-clef't, the two upper
teeth often more united than the others. Keel of the corolla
coiled in a spiral, together with the included stamens and
style. Stamens diadelphous (9 and 1). Style bearded length-
wise on the upper side; stigma oblique or on the side of the
style. Pod linear, 2-valved, several-many-seeded, tipped with
the remains of the style.
1.	P. perennis Walt. Wild Bean. Perennial, climbing high.
Flowers small, purple. Pods curved, drooping, 4-6-seeded. Thickets.
2.	P. vulgaris L. Common or Kidney Bean. Twiners (or some
varieties low and branching). Racemes of white or purplish flowers
shorter than the leaves. Pods straight or nearly so. Seeds not much
flattened. Cultivated, probably from tropical America.
3.	P. multiflorus Willd. Spanish Bean, Scarlet Runner. Steins
twining high. Flowers large and showy, white, scarlet, or variegated;
racemes longer than the leaves. The scarlet variety is the most com-
monly cultivated, for ornament. From tropical America.
48. GERANIACEAi. Geranium Family
Herbs or small shrubs. Leaves simple, usually with glan-
dular hairs which secrete an aromatic oil. Flowers bisexual,
axillary and solitary or clustered, actinomorphic or nearly so,
liypogynous, their parts in fives. Stamens 5 or 10, monadel-
phous at the base. Carpels 5, each 2-ovuled, splitting away
with their long styles when ripe from a central axis and thus
scattering the seeds.
I. GERANIUM L.
Herbs, rarely shrubs. Leaves with stipules, opposite or
alternate, usually cut or lobed. Flowers actinomorphic onGERANIUM FAMILY
141
1-2-flowered axillary peduncles. Sepals and petals 5. Stamens
10, ripening in 2 sets. Ovary 5-lobed, 5-beaked; stigmas 5.
1.	G. maculatum L. Wild Crane’s-Bill, Wild Geranium.
Perennial, with an erect, hairy stem, 12-18 in. high. Leaves about
5-parted, marked with pale blotches, the basal leaves long-petioled.
Flowers large (1 in. or more in diameter), light purple, somewhat
corymbed. Petals entire, twice as long as the calyx, the claw bearded.
Open woods and thickets; common.
2.	G. Robertianum L. Herr Robert. Annual or biennial. Stems
somewhat hairy, weak and spreading, reddish. Leaves of 5 leaflets,
the latter once or twice pinnately cut, long-petioled. Flowers light
purple, about } in. in diameter, streaked with dark and light red.
Claws of petals smooth. Damp woods and ravines E.
II. PELARGONIUM L’Her.
Perennial herbs or shrubs. Leaves with stipules, scented.
Flowers much as in the preceding genus, but one of the sepals
hollowed out below into a nectar-bearing tube extending down
the pedicel. The 2 upper petals different in size or shape from
the other 3. Cultivated from the Cape of Good Hope. [Most
of the species are commonly, though not quite correctly, called
geraniums.” Only a few of the commonest are here described.]
1.	P. peltatum Ait. Ivy Geranium. Stems somewhat prostrate and
trailing. Leaves somewhat peltate, smooth or nearly so. Flowers
pink or white.
2.	P. zonale Willd. Horseshoe Geranium. Stem erect, widely
branched, woody below. Leaves alternate, opposite or sometimes in
threes, round or kidney-shaped, palmately veined, crenate, downy,
usually with a dark zone near the middle. Flowers in a long pedun-
cled umbel, showy, red or white, often double. Numberless varieties
in cultivation.
3.	P. graveolens Ait. Rose Geranium. Stem erect or ascending,
densely downy, 1-3 ft. high. Leaves alternate, palmately lobed or
divided, the lobes often finely dissected, rolled under at the edges.
Flowers umbeled, small, light purple with darker veins; whole
plant very fragrant. Common in cultivation.
4.	P. odoratissimum Ait. Nutmeg Geranium. Branches crooked
and straggling from a very short, moderately stout main stem. Leaves
small, roundish and scalloped, covered with velvety down, very fra-
grant. Flowers white, inconspicuous, on short pedicels the petals
hardly longer than the calyx.KEY AND FLORA
142
49. OXALIDACEiE. Wood Sorrel Family
Herbs or woody plants. Leaves compound. Flowers in fives,
bisexual, actinomorphic, hypogynous. Stamens 10, somewhat
monadelphous at the base. Ovary with several ovules in each
cell. Fruit a capsule.
OXALIS L.
Acid herbs. Leaves basal or alternate, with or without
stipules, usually of 3 leaflets, which droop at night. Sepals 5.
Petals 5. Stamens 10. Ovary 5-lobed, 5-celled; styles 5.
1.	0. Acetosella L. Wood Sorrel. Apparently stemless, from a
creeping, scaly rootstock. Leaves all basal, long-petioled, of 3 in-
versely heart-shaped leaflets ; scape slender, 2-5 in. high, 1-flowered.
Flowers nearly 1 in. in diameter, white, veined with red or purple.
Cold woods N.
2.	0. violacea L. Violet Wood Sorrel. Perennial from a
bulbous root, apparently stemless. Leaves long-petioled ; leaflets
inversely heart-shaped, sometimes slightly downy, often with a dark
zone near the middle. Scapes usually longer than the petioles, uin-
bellate.ly 4-10-flowered; pedicels slender. Flowers violet-purple, nod-
ding. Petals obtuse, 2-3 times as long as the sepals; scapes and
petioles 4-5 in. long. Common in rich woods.*
3.	0. corniculata L. Common Yellow Wood Sorrel. Probably
flowering the first year but perennial, propagated by slender whitish
rootstocks. Erect or decumbent, often sparsely hairy, usually 1 ft.
or less in height. Stem leafy, the leaves often appearing whorled.
Leaflets thin, green or purplish, often ciliat.e. Peduncles few-flowered,
the ascending pedicels, clad with spreading hairs, forming unsym-
metrical umbels or cymes at their summits. Flowers yellow, about
5 in. in diameter. Pods hairy, columnar, grooved, often t in. or more
in length. A common weed in light soil.
50. TROPAJOLACEAi. Indian Cress Family
Smooth and tender herbaceous plants, with biting juice, often
climbing by the petioles of their simple leaves. Leaves alter-
nate, without stipules. Peduncles axillary, 1-flowered. Sepals
3-5, the upper one with a long, distinct spur. Petals 1-5,
hypogynous, not always all alike. Stamens 6-10, perigynous,FLAX FAMILY
143
distinct. Ovary 1, 3-angled, made up of 3-5 1-ovuled carpels;
style 1; stigmas 3-5. Fruit not opening.
TROPiEOLUM L.
Characteristics of the genus those of the family above given,
together with the following :
Petals usually 5, clawed, the 2 upper inserted at the mouth
of the spur and unlike the 3 lower ones. Stamens S, ripening
unequally, the filaments curved. Fruit 3-celled, 3-seeded. Cul-
tivated from S.A. for the very showy flowers and the sharp-
flavored fruits, which are often pickled.
1. T. majus L. Common Nasturtium. Climbing by the petioles
6-8 ft. (there is also a low variety which does not climb). Leaves
roundish but more or less 6-angled, peltate, with the petiole attached
near the middle. Flowers varying from almost white to nearly black,
but commonly crimson, scarlet, or flame color.
51. LINACE.®. Flax Family
Herbs, shrubs, or trees. Leaves usually alternate, simple,
entire, sometimes with stipules. Flowers variously clustered.
Sepals 5, distinct or united. Petals 5, hypogynous. Stamens
5, monadelphous below. Pod S-10-seeded, with twice as many
cells as there are styles.
LINUM L.
Herbs or small shrubs, with tough, fibrous bark. Leaves
sessile. Flowers in corymbs or panicles. Sepals 5, entire.
Petals 5, distinct or united below, falling in a few hours after
expanding.
1.	L. usitatissimum L. Common Flax. Stem erect, with corymbed
branches at the top. Leaves narrowly lanceolate. Flowers handsome,
large, blue. Cultivated for the fiber. From Europe; introduced here
to some extent.
2.	L. virginianum L. Wild Flax. Stem rather slender, erect
and cylindrical; branches cylindrical. Leaves small, varying from
oblong to lanceolate or spatulate. the lower often opposite. Flowers
small, yellow. Capsules flattened at right angles to the pedicels. I try
woods and pastures.144
KEY AND FLORA
52. RUTACEAJ. Rue Family
Shrubs or trees. Leaves alternate, compound, without stip-
ules, marked with translucent dots. Flowers usually actino-
morphic. Sepals and petals 3-5 or none ; petals hypogynous
or perigynous when present. Stamens as many or twice as
many as the sepals, inserted on the glandular disk. Pistils
2-5, often partially united. Fruit a capsule, a key fruit, or in
the important genus Citrus (orange, lemon, lime, etc., not here
described) a leathery-skinned berry, the outer part of the skin
containing many spherical oil cavities.*
I. XANTHOXYLUM
Trees or shrubs ; bark, twigs, and petioles usually prickly;
leaves odd-pinnate, marked with translucent dots. Flowers in
axillary or terminal cymes or umbels, monoecious or dioecious.
Sepals and petals 3-5 or none. Stamens 3-5, hypogynous..
Pistils 2-5, distinct. Carpels 2-valved, 1-2-seeded; seeds
smooth and shining.*
1. X. americanum Mill. Northern Prickly Ash, Toothache
Tree. A prickly shrub, 8-12 ft. high, with aromatic bark. Leaves
pinnately compound; leaflets ovate-oblong. Flowers small and
greenish, in axillary umbels, appearing before the leaves. Petals
4-5. Pistils 3-5, the styles slender. Pods rather globose, somewhat
more than J in. in diameter, roughish, borne on a short stalk above
the receptacle, with a strong scent of lemon and tasting at first aro-
matic, then burning. Rocky woods, ravines, and river banks.
II. PTELEA L.
Shrubs with smooth and bitter bark. Leaves with 3 leaflets.
Flowers in terminal cymes, somewhat monoecious. Sepals 3-6,
deciduous, much shorter than the petals. Stamens 4-5, longer
than the petals and alternate with them. Pistillate flowers
producing imperfect stamens. Ovary compressed, 2-eelled.
Fruit a 2-celled, 2-seeded, broadly winged key.*
1. P. trifoliata L. Hop Tree, Wafer Ash. A shrub 4-8 ft. high.
Leaves long-petioled; leaflets oval or ovate, acute, obscurely serrate,POLYGALA FAMILY
145
the lateral ones oblique. Cymes compound. Flowers greenish. Sta-
mens mostly 4 ; filaments bearded; key about 1 in. in diameter; wing
notched, strongly netted-veined. Rocky banks; often cultivated.*
53. POLYGALACEAE. Polygala Family
Herbs or shrubs. Leaves alternate or nearly opposite, with-
out stipules, simple. Flowers not actinomorphic. Sepals un-
equal, the 2 inner wing-shapecl and petal-like. Petals 3-5,
hypogynous, the 2 lateral ones often united with the hooded
lower one into a tube, split open at the base behind. Stamens
8 ; filaments united into a split sheath, which is usually joined
to the petals ; anthers usually opening by pores. Ovary 2-
celled, 2-ovuled. [A difficult family for the beginner.]
POLYGALA L.
Herbs or shrubs. Flowers racemed or spiked, some of them
often eleistogamous. Petals united below to the stamen
sheath. Anthers opening by transverse pores.
1.	P. paucifolia Willd. Fringed Polygala, Babies’ Toes. May
Wings. A low perennial herb, with branches 3-4 in. high, from a
slender, creeping rootstock. Lower leaves scattered, small and scale-
like, the upper ones with petioles, crowded near the tips of the
branches, ovate or nearly so. Flowers of two kinds, the eleistoga-
mous whitish, fertile, borne underground along the rootstock, the
terminal flowers large and showy (nearly an inch long), rose-purple,
with a beautiful fringed crest. Woods, especially N. and E.
2.	P. Senega L. Seneca Snakeroot. A perennial herb, with
several erect stems arising from stout, hard, knotty rootstocks.
Leaves lanceolate, oblong or lance-ovate, sessile. Flowers all alike,
small, white, in solitary close spikes. Rocky woods.
54. EUPHORBIACEAi. Spurge Family
Herbs, shrubs, or trees, usually with a milky, more or less
acrid and sometimes poisonous juice. Flowers mostly apetal-
ous, monoecious or dioecious (Fig. 23). Ovary usually 3-celled,
with 1 or 2 ovules in each cell; stigmas as many as the cells146
KEY AND FLORA
or twice as many. Fruit a 3-lobed capsule. Seeds containing
fleshy or oily endosperm. Most of the family are natives of
hot regions, many of them of peculiar aspect from their adap-
tation to life in dry climates. [The family is too difficult for
the beginner in botany to determine many of its genera and
species with certainty, but a few are described below.]
Shrubs or herbs. Leaves alternate. Flowers monoecious,
staminate and pistillate intermixed in the cymes, apetalous.
Calyx large, white, 5-lobed, corolla-like. Stamens numerous,
usually monadelphous. Ovary usually 3-celled, 3-seeded ; styles
3, united at the base, several-parted.*
1. J. stimulosa Michx. Spurge Nettle. Perennial herbs armed
with stinging hairs; stems erect, branched, bright green with white
lines, 8-15 in. high. Leaves long-petioled, deeply palmately 3-5-
lobed, the lobes irregularly cut and toothed, often mottled. Sepals
white, spreading. Seeds oblong, smooth, mottled. In dry woods S.*
A. flower cluster with involucre, the whole appearing like a single flower.
B, a single staminate flower: a, anther. C, fertile flower, as seen after
the removal of the sterile flowers. D, partly matured fruit: i, involucre;
s, stigmas; c, capsule
Herbs or shrubs, with milky juice, often poisonous. Flowers
monoecious, inclosed in a 4-5-lobed involucre, which is often
showy and resembles a calyx or corolla, usually bearing large
I. JATROPHA L.
s
Fig. 23. Euphorbia corollata
II. EUPHORBIA L.Sl'URGE FAMILY
147
glands at its notches. Sterile flowers many, borne inside the
involucre at its base (Fig. 23, A), each consisting only of a
single stamen attached by a joint to a pedicel which looks like
a filament. Fertile flower standing alone at the center of the
involucre (Fig. 23, C) (soon pushed out by the growth of its
pedicel), consisting only of a 3-lobed and 3-celled ovary, 3 2-
cleft styles, and 6 stigmas. Pod 3-celled and 3-seeded.
A.	Cultivated shrubs.
1.	E. splendens Bojer. Crown of Thorns. An extremely prickly
shrub, with many erect, few-leaved branches. Leaves obovate or'
obovate-spatulate, mucronate, entire, each with two very sharp
prickles (longer than the petiole) as stipules. Peduncles long,
sticky, each bearing* 2-4 objects which appear to be showy scarlet
flowers, but which are actually 2-bracted involucres containing the
true flowers. Involucral scales somewhat kidney-shaped, mucronate.
Flowering all the year round. Cultivated in greenhouses. From
Mauritius.
B.	Herbs with rather showy white flower clusters.
2.	E. marginata Pursb. Snow on the Mountain. Annual. Stem
stout, 1-3 ft. high. Leaves sessile, ovate, obovate or oblong, acute,
f-3 in. long, the upper ones wdiorled and with white petal-like mar-
gins. Involucres 5-lobed in an umbel-like inflorescence with three
forking rays. In dry soil \Y. and commonly cultivated.
3.	E. corollata L. Flowering Spurge. Perennial. Stem erect,
umbellately branched above, smooth or downy, 1-3 ft. high. Leaves
of the stem alternate, those of the branches usually opposite or
whorled, rather thick, oval to narrowly oblong, pale beneath, usu-
ally sfightly downy. Flowering branches repeatedly forked; invo-
lucres terminal and in the forks of the branches, peduncled ; glands
4-5, oblong, green; appendages white and petal-like, showy. Cap-
sule erect, seed smooth or faintly pitted. Common in dry, open
woods.
C.	Herbs: Xo. 4 a native species: Xft, 5 cultivated from Europe or
escaping from gardens. Flower clusters in umbels, not white. Involucre
4- or 5-lobed, each lobe u-ilh a gland.
4.	E. dictyosperma Fisch. & Mey. Annual. Stem slender, S-1S in.
high, erect. Stem leaves oblong-spatulate to obovate, serrate; floral
ones roundish-ovate, somewhat heart-shaped. Flower cluster a com-
pound umbel, the rays once or twice 3-forked, then 2-forked. Seeds
covered with a network. Prairies and roadsides.148
KEY AND FLORA
5. E. Cyparissias L. Cypress Spurge, Cypress, Graveyard
Moss. A perennial, in dense clusters 6-12 in. high, from running
rootstocks. Leaves much crowded, all sessile, the stem leaves linear,
floral ones broadly heart-shaped. Flower cluster a simple, many-
rayed umbel. Glands crescent-shaped. Cemeteries, roadsides, etc.,
escaped from cultivation; also cultivated in old gardens. From
Europe.
55. ANACARDIACEAS. Sumac Family
Trees or shrubs, with resinous, acrid, or milky sap. Leaves
simple, of 3 leaflets or pinnately compound, alternate, with-
out stipules. Flowers bisexual or unisexual, small. Calyx
3-5-parted, persistent. Petals 3-5 or wanting. Stamens as
many as the sepals or sometimes twice as many, inserted in
the base of the calyx, distinct. Ovary free, 1-celled; styles
1-3. Fruit a 1-seeded drupe.*
RHUS L.
Trees or shrubs. Leaves of 3 leaflets or odd-pinnate.
Flowers in spikes or panicles. Calyx mostly 5-parted. Petals
and stamens 5. Pistil 1, sessile; styles 3, terminal. Fruit
small, smooth or downy.*
1.	R.typhinaL. Stag-Horn Sumac. A small tree, 20-40ft. high;
branches and petioles closely velvety-hairy. Leaves odd-pinnate,
leaflets 17-27, lanceolate-oblong, taper-pointed at the apex, very
obtuse at the base, sharply serrate, smooth above, pale and downy
beneath. Flowers somewhat momeeious, in dense terminal panicles.
Fruit red, with crimson hairs. Dry hillsides N. and E.*
2.	R. glabra L. Sumac. A shrub or small tree, sometimes 25-30
ft. high; branches downy. Leaves odd-pinnate, main midrib downy
and wing-margined; leaflets 0-21, ovate-lanceolate, acute at the apex,
inequilateral, entire or slightly toothed, smooth and green above,
pale and downy beneath. Panicle often large and spreading ; flowers
somewhat monoecious. Fruit red, hairy, acid. Open woods.*
3.	R. Vernix L. Poison Sumac, Poison Dogwood. A very
smooth shrub with gray bark, 6-18 ft. high. Leaves Large and
glossy, with 7-13 obovate-oblong, entire leaflets. Flower clusters
loosely flowered, axillary panicles. Fruit smooth, greenish-yellow.
Swamps and wet openings in woods N. and E. Plant more poison-
ous than the following species.IIOLLY FAMILY
149
4. R. Toxicodendron L. Poison Vine, Poison Ivy, Mercery,
Black Mercury. .Stem a woody vine climbing high by aerial root-
lets, or sometimes short and erect. Leaves petioled, of 3 leaflets,
downy; leaflets ovate or oval, taper-pointed, entire or somewhat
dentate, often angled or lobed. Flowers dioecious, in loose axillary
panicles. Fruit nearly white, smooth. Common in open woods and
along fences.. Plant poisonous to the touch.*
56. AQUIF0LIACEA5. Holly Family
Trees or shrubs. Leaves simple, alternate, petioled; stip-
ules small or wanting. Flowers small, greenish, clustered or
solitary in the axils, usually dioecious. Calyx 4-9-parted.
Petals 4-9, somewhat united at the base. Stamens inserted
in the tube of the corolla and alternate with its lobes. Ovary
free, 4-9-celled, with a single ovule in each cell. Fruit a
berry-like drupe, 4-9-seeded.*
ILEX L.
Small trees or shrubs. Leaves usually leathery, often per-
sistent and evergreen; stipules minute. Flowers axillary,
4-9-parted, the fertile often solitary and the staminate clus-
tered. Fruit a drupe with 4-9 nutlets.*
1.	I. opaca Ait. Holly. Trees with smooth, light-colored bark,
and hard, very white wood ; young twigs downy. Leaves leath-
ery, oval or ovate, margin prickly-toothed, dark green and shining
above, paler and sometimes slightly downy beneath. Peduncles short,
bracted. Flowers 4-parted; staminate flowers in small cymes, the
pistillate ones usually solitary. Fruit bright red. Damp, sandy soil
£. and S*
2.	I. decidua Walt. Deciduous Holly. Small trees; twigs smooth.
Leaves thin, obovate, obtuse or sometimes acute at the apex, scal-
loped, smooth, deciduous. Flowers in sessile clusters, 4-6-parted.
Fruits very numerous, bright red. On low ground S.*
3.	I. verticillata Gray. Black Alder, Winter berry. A much
branched shrub 6-8 ft. high. Leaves thin, oval or obovate, taper-
pointed, serrate, 11-2 in. long. Flowers greenish-white, on very
short peduncles. Fruit bright red, 1, 2, or 3 in a leaf axil, remain-
ing long after the leaves have fallen. Swampy ground and damp
woods and thickets.150
KEY AND FLORA
57. CELASTRACEAi. Wahoo Family
Trees or shrubs, sometimes climbing. Leaves simple, oppo-
site or alternate. Flowers small, in cymes. Calyx small,
4-5-lobed, persistent. Petals 4-6, short. Stamens 4-6, alter-
nate with the petals and inserted with them on a disk.
Ovary sessile, 3-5-celled; style entire or 3-5-cleft; ovules 2 in
each cell. Seeds usually covered with an appendage (aril) grow-
ing from the hilum.
I. EVONYMUS L.
Shrubs with 4-angled branches. Leaves opposite. Flowers
in axillary, peduncled cymes, purplish or greenish, small.
Sepals and petals 4-5, spreading. Stamens as many as the
petals, short. Ovary 3-5-celled, with 2 ovules in each cell.
Seeds inclosed in a red, fleshy pulp.*
1.	E. atropurpureus Jacq. Wahoo. A tree-like shrub 10-15 ft.
high. Leaves oval to ovate, taper-pointed, finely serrulate, minutely
downy petioles Jin. long. Peduncles slender, 3-forked, several-flow-
ered. Flower purplish. Capsule deeply 3-5-lobed, smooth. River banks.
2.	E. americanus L. Strawberry Bush. A shrub 3-S ft. high.
Leaves short-petioled, ovate to ovate-lanceolate, acute or taper-pointed
at the apex, finely serrulate, smooth or slightly hairy. Peduncles
axillary, slender, 1-3-flowered. Flowers greenish. Capsule 3-5-angled,
warty. In low, shady woods.
3.	E. obovatus Nutt. Running Strawberry Bush. A low shrub,
the trailing and rooting branches not usually rising more than 1 or
2 ft. from the ground. Leaves thin, obovate or oblong, mostly taper-
ing to the base. Flowers and fruit nearly as in E. americanus. In
damp woods.
II. CELASTRUS L.
A woody, twining shrub. Leaves alternate. Flowers dioe-
cious or somewhat monoecious, small, greenish, clustered at
the ends of the branches. Pod 3-celled, S-valved, looking like
an orange-colored berry, which on opening shows the scarlet
arils of the seeds.
1. C. scandens L. Waxwork, Climbing Bittersweet. Climb-
ing 10-15 ft. Leaves ovate-oblong, 2-4 in. long, finely serrate,
taper-pointed. In thickets and along fences; also planted for the
showy scarlet seeds, which retain their color for many months.BLADDER NUT FAMILY
151
58. STAPHYLEACEiE. Bladder Nut Family
Shrubs. Leaves pinnately compound, with stipules, and
the leaflets with little individual stipules (stipels). Flowers
regular and perfect. Calyx lobes 5. Petals 5, inserted in or
around a saucer-shaped disk. Stamens 5, alternate with the
petals, perigynous. Ovary 2-3-celled, with the carpels more
or less distinct; ovules several; styles 2-3, somewhat united
below. Fruit usually 1-few-seeded.
STAPHYLEA L.
Calyx deeply 5-parted, the lobes appearing like separate
sepals, erect. Petals spatulate, borne on the rim of the thick
disk. Pod large, papery, 3-celled, finally opening at the top.
Seeds 1-4 in each cell, bony.
1. S. trifolia L. American Bladder Nut. A shrub 6-12 ft.
high, with smooth, slender, greenish-striped, at length gray, branches.
Leaves long-petioled, with 3 ovate, taper-pointed, finely serrate leaf-
lets. Damp thickets.
59. ACERACEiE. Maple Family
Trees or shrubs, with abundant, often sugary sap. Leaves
opposite, simple and palmately lobed, or pinnate, without
stipules. Flowers regular, mostly somewhat monoecious or
dioecious, in axillary and terminal cymes or racemes. Calyx
4-9-parted. Petals as many as the lobes of the calyx or none.
Stamens 4-12, hypogynous. Ovary 2-celled; styles 2. Fruit
a double key.*
ACER L.
Characteristics of the genus as above given for the family.
1. A. saccharum Marsh. Sugar Maple. A large tree. Leaves
simple, palmately lobed, truncate or heart-shaped at the base, lobes
sinuate-toothed and acuminate, pale and slightly downy beneath.
Flowers appearing with the leaves, on clustered drooping pedicels.
Calyx bell-shaped, fringed. Petals none. Keys smooth, wings about152
KEY AND FLORA
1-1J in. long. In cold woods, move abundant northward. The sap
of this tree is the principal source of maple sugar, and some forms
of the tree produce the curled maple and bird’s-eye maple used in
cabinet making.*
2.	A. saccharinum L. White Maple, River Maple. A tall
tree with the main branches slender and rather erect. Leaves very
deeply 5-lobed, with the notches rather acute, silvery-white, and when
young downy on the lower surface, the divisions narrow, coarsely
cut and toothed. Flowers greenish, in umbel-like clusters, appearing
long before the leaves. Petals absent. Fruit woolly at first, then
smooth, with diverging wings, the whole 2—3 in. long. Common on
river banks S. and \\r., also planted for a shade tree, but not safe,
as the branches are easily broken off by the wind.
3.	A. rubrum L. Red Maple. A small tree with red or purple
twigs. Leaves simple, broadly ovate, palmately 3-5-lobed or some-
times merely serrate or cut-toothed, taper-pointed at the apex,
rounded or heart-shaped at the base, smooth or downy, becoming
bright red in autumn. Flowers appearing before the leaves on erect,
clustered pedicels. Petals red or yellow, oblong or linear. Fruiting
pedicels elongated and drooping. Key red, smooth, wings about an
inch long. Swamps and river banks E.*
4.	A. Pseudo-Platanus L. Sycamore Maple. Easily recognized
by its drooping clusters of rather large green flowers, which appear
with the leaves. Cultivated from Europe.
5.	A. platanoides L. Norway Maple. A large tree, with milky
sap, which exudes from broken shoots or leafstalks in the spring.
Cultivated from Europe; a very desirable shade tree.
6.	A. Negundo L. Box Elder. A small tree. Leaves opposite,
pinnately 3-5-foliate; leaflets ovate, lobed, toothed or entire, downy
when young. Flowers dioecious, appearing from lateral buds before
or with the leaves; the staminate on long and drooping pedicels,
the pistillate in drooping racemes. Keys smooth, 1-11 in. long.
River banks. Often cultivated as a quick-growing shade tree.*
60. HIPPOCASTANACE2E. Buckeye Family
Trees or shrubs. Leaves opposite, long-petioled, palmately
compound. Flowers showy, somewhat monoecious, in termi-
nal panicles. Calyx 5-lobed, oblique. Petals 4-5, unequal.
Stamens 5-8, liypogynous. Pistil 1; ovary 3-celled, 2 ovules
in each cell ; style slender. Fruit a 1-3-celled, leathery cap-
sule, 1-3-seeded. Seeds with a large scar.*BALSAM FAMILY
153
■ffiSCULUS L.
Characteristics of the genus as abov’e given for the family.
1.	2£. Hippocastanum L. Hokse-Chestxut. A round-topped tree
with frequently forking branches and stumpy fuigs. Leaves very
large, with 7 straight-veined leaflets. Flowers large and showy.
Corolla open and spreading, of 5 white petals, spotted with purple
and yellow. Stamens with long, curved filaments. Fruit large, cov-
ered with stout, soft prickles when young. Cultivated from Asia.
2.	JE. glabra Willd. Ohio Buckeye. A large tree, not unlike
a horse-chestnut. Leaflets generally 5. Flowers small. Corolla of I
upright, pale yellow petals. Stamens curved, about twice as long as
the petals. Fruit prickly at first. River banks.
3.	M. octandra Marsh. Sweet Buckeye. Varying in size from a
low shrub to a tall tree. Leaves with 5-7 leaflets. Flowers in a short,
dense panicle. Petals 4, in 2 unlike pairs, bending inward; blades of
the longer pair very small. Fruit not prickly. Woods W. and S.
4.	M. Pavia L. Red Buckeye. Shrubs. Stems erect, branched,
4-8 ft. high. Leaflets usually 5, lanceolate to narrowly oval, taper-
pointed at both ends, finely serrate, smooth or nearly so. Flowers
in dense, erect panicles, bright red. Stamens rather longer than the
petals. Fruit nearly smooth. Common in open woods.*
61. BALSAMINACE2E. Balsam Family
Tender, fleshy-stemmed, annual herbs. Leaves simple, with-
out stipules. Flowers bisexual, zygomorphic. Sepals usually
3, the largest one with a spur. Petals 3. Stamens 5, dis-
tinct or nearly so. Ovary 5-celled, bursting when ripe into
5 valves.
IMPATIENS L.
Characteristics of the genus those above given for the family.
Fruit a capsule (very fleshy in our species), which when ripe
bursts open with considerable force, throwing the seeds about.
1. I. pallida Xutt. Wild Balsam, Lady's Supper. Stem 3-5 ft.
high, branching. Leaves oblong-ovate, 2-6 in. long, the lower often
long-petioled, the upper nearly sessile. Peduncles axillary, 1-3 in.
long, slender, 2-5-flowered. Flowers pale yellow, slightly dotted
with brownish-red. Sac of the large sepal broader than it is long,
ending in a recurved spur about \ in. long. Damp, shaded ground,
not very common.154
KEY AND FLORA
2. I. biflora Walt. Wild Balsam, Lady’s Slipper, Jewelweed,
Sxapweed, Kicking Colt. Stem 2-4 ft. high, branching. Leaves
rhombic-ovate, 1-4 in. long. Peduncles about 1 in. long, generally
2-3-flowered. Flowers orange color, with many pretty, large, reddish-
brown spots. Sac longer than it is brOad, ending in a recurved spur
about 1 in. long. Damp, shaded ground, commoner than No. 1 and
usually blossoming earlier.
62. RHAMNACE2E. Buckthorn Family
Trees or shrubs. Leaves simple, often 3-5-nerved; stipules
small. Flowers small, sometimes unisexual, green or yellow.
Calyx 4-5-lobed. Petals 4, 5, or absent, inserted on a disk at
the throat of the calyx, very small, hooded, usually with
claws. Stamens 4-5, inserted with the petals and opposite
them, often inclosed by the petals; filaments awl-shaped;
anthers small, versatile. Ovary 3-celled, 3-ovuled.
I. BERCHEMIA Neck.
Shrubs; stems twining or erect. Leaves alternate, promi-
nently pinnate-veined, stipules minute. Flowers in axillary
or terminal panicles, or rarely solitary. Calyx tube hemi-
spherical, 5-lobed. Petals 5, sessile, concave, as long as the
calyx. Ovary 2-celled, half inferior ; stigmas 2. Fruit an oval,
2 seeded drupe. *
1. B. scandens Trel. Supple Jack, Rattan Vink. Woody, often
twining high; older bark yellowish, twigs purple, wood very tough.
Leaves ovate or oval, acute or obtuse, cuspidate at the apex, rounded
at the base, wavy on the margins, green above, pale beneath.
Flowers in small panicles. Fruit purple. In moist woods and along
streams S.*
II. RHAMNUS I,.
Leaves alternate, deciduous. Flowers in small, axillary
cymes, often unisexual. Petals 4-5 or wanting. Stamens 4
or 5, very short. Drupe, 2-4-seeded.
1. R. lanceolata Pursh. A tall shrub. Leaves with short petioles,
taper-pointed or somewhat, obtuse, very variable in size, smooth or
nearly so above, more or less downy beneath, finely serrate. FlowersVINE FAMILY
155
2 or 3 together in the axils, greenish, about $ in, in diameter, usually
dicecious, appearing at the same time as the leaves. Calyx 4-lobed.
Petals 4. Stamens 4. Fruit black, about 1 in. in diameter. Hills
and river banks.
2. R. caroliniana Walt. Carolina Buckthorn. A small tree
with black bark and very hard wood; twigs finely downy. Leaves
alternate, prominently veined, elliptical to broadly oval, entire or
obscurely serrate, smooth or sometimes downy below; petioles slen-
der, downy. Flowers in axillary, peduncled umbels; petals minute.
Fruit globose, J-J in. in diameter, 3-seeded. Seeds smooth. On river
banks.*
III. CEANOTHUS L.
Shrubs. Leaves alternate, petioled. Flowers bisexual, in
terminal panicles or corymbs formed of little umbel-like clus-
ters. Calyx tube top-shaped or hemispherical, with a 5-lobed
border. Petals 5, with hoods, on slender claws. Stamens 5;
filaments long and thread-like. Fruit dry, 3-lobed, splitting
when ripe into 3 carpels.
1.	C. americanus L. Neiv Jersey Tea, Red Root. Shrub, with
many branching stems, 1-3 ft. high, from a deep red root. Leaves
1-3 in. long, ovate or nearly so, acute or taper-pointed at the tip,
obtuse or somewhat heart-shaped at the base, downy beneath, serrate,
3-nerved. Flowers small, w'hite.
2.	C. ovatus Desf. Smaller Red Root. Similar to C. americanus
but usually smaller and nearly smooth. Leaves narrowly oval or
‘■Uiptical-lanceolate, finely glandular-serrate, 1-2 in. long. Dry rocks
and prairies, especially S.W.
63. VITACEIE. Vine Family
Shrubs, with the stem swollen at the insertion of the peti-
oles and climbing by tendrils borne opposite the leaves.
Leaves alternate, with stipules simple or compound. Flowers
small, greenish,- generally in clusters, borne in similar posi-
tions to the tendrils, hypogynous or nearly so. Sepals, petals,
and stamens 4-5. Carpels 2, each 2-ovuled. Calyx very small.
Corolla deciduous, the petals often hooded. Stamens opposite
the petals. A disk inside the calyx bears nectar and its lobes
alternate with the stamens. Fruit a berry.156
KEY AND FLORA
I.	PSEDERA Neck. (PARTHENOCISSUS)
Woody vines, climbing by tendrils and rootlets. Leaves
palmately compound. Flowers in compound cymes, perfect
or somewhat monoecious. Petals 5, distinct, spreading; disk
none. Stamens 5. Ovary 2-celled, 4-ovuled. Fruit a 1-4-
seeded berry, not edible.*
1.	P. quinquefolia Greene. Woodbine, Virginia Creeper. Stem
smooth. Leaflets dull green, paler below; tendrils 5-1:2-branched,
most of the branches ending in disks which cling to supporting
objects. Flowers panicled, the main branches of the cluster unequal.
Fruit hardly fleshy. Thickets, common.
2.	P. vitacea Greene. "Woodbine, Virginia Creeper. Stem
smooth or slightly downy. Leaflets deep green above, not much
paler below; tendrils 2-5-branched, the branches usually without
disks at the tips. Flower cluster forking regularly, the main
branches nearly equal. Fruit more fleshy than in No. 1. Moist
woods and thickets in deep, rich soil; common.
3.	P. tricuspidata Rehder. Japanese Ivy, Boston Ivy. A freely
branching, hardy climber. Tendrils numerous, branching with closely
adhesive disks. Leaves occasionally with 3 leaflets, but usually with
only one, which is jointed with the main petiole and in autumn falls
before the petiole ; leaflet 3-lobed or only scalloped, roundish-ovate or
heart-shaped, rather thick and shining. Cultivated from Japan.
n. VITIS L.
Climbing woody vines. Stems with enlarged joints, climb-
ing by tendrils opposite some of the leaves. Leaves simple,
palmately veined or lobed ; stipules small, soon deciduous.
Flowers mostly somewhat monoecious or dioecious. Petals
often united at the apex and not expanding. Stamens in-
serted between the lobes of the disk. Ovary usually 2-celled,
4-ovuled. Fruit juicy, 1-4-seeded.*
1. V. labrusca L. Fox Grape. Stems climbing high, often 1 ft.
or more in diameter; bark shreddy, coming off in long strips; young
branches woolly. Leaves broadly heart-shaped, more or less deeply
3-5-lobed, mucronate-dentate, very woolly when young, becoming
smooth above. Panicles of pistillate flowers compact, of staminate
flowers looser. Fruit about J in. in diameter, dark purple or some-
times nearly white. In rich woods E., S., and S.W. Many of the
cultivated varieties, such as Concord, Niagara, etc., have been devel-
oped from this species.*LINDEN FAMILY
157
2.	V. aestivalis Michx. Summer Grape. Stem climbing high;
bark shreddy. Leaves broadly heart-shaped, 3-5-lobed, the lobes
dentate, notches rounded, white-woolly when young, often nearly
smooth when old; tendrils or panicles opposite 2 out of every 3
leaves, panicles long and slender. Fruit dark blue, small, very acid.
In rich woods E. and S.*
3.	V.cinerea Engelm. Downy Grape. Branchlets angular, covered
with whitish or grayish down. Le'aves entire or slightly 3-lobed, with
whitish or grayish down, especially on the under side. Berries small,
black, without bloom. S.W.
4.	V. cordifolia Michx. Frost Grape, Chicken Grape. Leaves
rather smooth, thin, and shining, either not lobed or somewhat 3-lobed,
heart-shaped, with the notch at the base deep and acute, taper-pointed,
with large, sharp teeth. Flower clusters large and loose. Grapes
shining black, very sour, not ripening until after frosts; seeds 1 or
2, rather large. Moist thickets and banks of streams S.
5.	V. vulpina L. Riverside or Sweet-Scented Grape. Re-
sembling V. cordifolia, but the leaves more shining and more com-
monly 3-lobed. Fruit bluish-black, with a bloom, moderately sweet,
| in. or more in diameter, beginning to ripen in July. Along ponds
and streams, especially W. and S.W.
6.	V. rotundifolia Michx. Muscadine Grape. Stem climbing
high; joints short; bark not shreddy; wood very hard, often pro-
ducing long, aerial roots. Leaves orbicular, heart-shaped at the base,
coarsely toothed, nearly or quite smooth. Panicle small. Grapes few
in a cluster, large. The original form of the Scuppernong grape. S.*
64. TILIACEiE. Linden Family
Trees or shrubs, rarely herbs. Leaves alternate, with
stipules. Flowers bisexual in cymes, the latter usually in
corymbs or panicles. Sepals 5. Petals 5 or fewer, or want-
ing. Stamens many, inserted on a swollen disk. Ovary 2-10-
celled, with one or more ovules in each cell. Fruit 1-12-celled,
dry or berry-like.
TILIA L.
Trees with rough gray bark on the trunk ; bark of the twigs
smooth, lead-colored; wood white and soft. Leaves cordate,
usually inequilateral. Cymes axillary or terminal, peduncles
adnate to a large, prominently veined, leaf-like bract. Flowers
yellowish-white. Sepals 5. Petals 5. Stamens many, in 5158
KEY AND FLORA
groups. Ovary 5-celled, with 2 ovules in each cell; stigma
5-lobed. Capsule 1-celled, 1-2-seeded; peduncle and bract
deciduous with the matured fruit, the bract forming a wing
by which the fruit is often carried to a considerable distance.*
1.	T. americana L. Basswood, Wiiitewood. A large tree, some-
times 125 It. high. Leaves larger than in No. 2 (2-5 in. wide), often
unsyrnmetrical, heart-shaped or truncate at the base, sharply toothed.
Floral bract often narrowed at the base. Fruit somewhat ovoid, i
in. or more in diameter. Common in rich woods; occurs farther N.
than No. 2.
2.	T. Michauxii Nutt. Basswood. A tree of medium size. Leaves
ovate, acuminate at the apex, obtuse and oblique at the base, mucro-
nate-serrate, woolly on both sides or smooth above when old. Flowers
fragrant; floral bract 2-0 in. long, usually rounded at the base. Fruit
globose, about | in. in diameter. In rich woods. Bees gather large
quantities of nectar from the flowers.*
3.	T. heterophy 11a Vent. White Basswood. A large tree. Leaves
larger than in T. americana or T. Michau.rii, often (5-8 in. long, smooth
and bright green above, silvery-downy underneath. In wooded or
mountainous districts.
4.	T. europasa L. European Linden. A good-sized tree. Leaves
roundish, obliquely heart-shaped, abruptly taper-pointed, finely
toothed. Flowers differing from Nos. 1 and 2 in the absence of
petal-like scales at the bases of the stamens. Cultivated from
Europe.
65. MALVACEAE. Mallow Family
Herbs or shrubs, with simple, alternate, palmately-veined
leaves, with stipules. Flowers actinomorphic. Sepals 5, often
surrounded by an involucre at the base. Petals 5. Stamens
numerous, monadelphous. Pistils several, more or less dis-
tinct. Fruit a several-celled capsule or a collection of 1-seeded
carpels.
I. ABUTILON Adans.
Calyx 5-cleft, the tube often angled. Styles 5-20, with
knobbed stigmas. Carpels as many as the styles, arranged in
a circle, each 1-celled, 3-6-seeded, and opening when ripe by
2 valves.
1. A. striatum Dicks. Tassel Tree, Flowering Maple. A
shrub 5-10 ft. high. Leaves maple-like. Flowers showy, solitary,MALLOW FAMILY
159
nodding on slender peduncles. Corolla not opening widely, orange,
striped with reddish-brown veins. Column of stamens projecting
beyond the corolla like a tassel. Cultivated in hothouses. From
Brazil.
II.	MALVASTRUM Gray
Calyx with an involucel of 2 or 3 bractlets or none. Petals
notched at the end or entire. Styles 5 or more, with knobbed
stigmas. Carpels not splitting open or somewhat 2-valved, fall-
ing from the axis when mature, tipped with a point or beak.
1. M. coccineum Gray. Red False Mallow. Perennial, 4-10 in.
high, covered with a dense silvery down of star-shaped hairs. Leaves
3-5-partyd. Flowers in short spikes or racemes. Petals red, much
longer than the calyx. Carpels 10 or more, with a wrinkled network
on the sides. Prairies IV. and SAY.
III.	MALVA L.
Calyx 5-cleft, with a small, 3-leaved involucel. Petals ob-
cordate or truncate. Styles many, slender, with stigmas run-
ning down the sides. Carpels many, 1-seeded, arranged in a
circle and separating from each other, but not opening when
ripe.
1.	M. rotundifolia L. Common Mallow, Cheeses (from appear-
ance of the unripe fruit). A common biennial or perennial weed,
with nearly prostrate stems. Leaves long-petioled, round-kidney-
shaped, with crenate margins. Flowers small, whitish, on long-
peduncles.
2.	M. sylvestris L. High Mallow. Biennial or perennial. Stem
erect, 2-3 ft. high. Leaves 5-7-lobed. Flowers purplish, larger than
those of the preceding species.
IV.	CALLIRHOE Nutt.
Calyx naked, or with a 3-leaved involucel at the base. Petals
wedge-shaped, often toothed and fringed. Styles and stigmas
as in Malva. Carpels 10-20, joined in a circle, 1-seeded, beaked
at the tip.
1. C. alcasoides Gray. Light Poppy Mallow. Perennial. Stents
rather slender, 8-20 in. high, covered with close-lying stiff hairs.
Basal leaves triangular-heart-shaped, palmately lobed or incised;160
KEY AND FLORA
stem leaves palmately divided. Involucel none. Flowers pink or
white, about 1 in. in diameter. Carpels strongly wrinkled. In dry
soil W. and S.W.
2.	C. digitata Nutt. Fringed Poppy Mallow. Resembling
C. alcceoides. Flowers 1-’—2 in. in diameter. Petals reddish-purple
to white, fringed. In dry soil S.W.
3.	C. involucrata Gray. Purple Poppy Mallow. Perennial.
Stems 1-2 ft. high, procumbent or ascending. Leaves round-heart-
shaped, palmately lobed or cut. Involucel 3-leaved. Peduncles long,
slender, and 1-flowered. Flowers reddish-purple, 1-21 in. in diameter.
Carpels with a wrinkled network. In dry soil AY. and S.AAL
66. HYPERIC ACEAJ. St. John’s-wort Family
Herbs, shrubs, or trees. Leaves opposite, often covered
with translucent or dark dots, entire or with glandular teeth,
without stipules. Flowers usually in terminal cymes. Sepals
5, rarely 4. Petals as many as the sepals, hypogynous.
Stamens usually many, more or less grouped in bundles;
anthers versatile. Pod 1-celled, with 2-5 parietal placentae
and the same number of styles, or else 3-7-celled, split-
ting along the partitions.
HYPERICUM L.
Herbs, shrubs, or small trees. Leaves sessile, often dotted.
Flowers yellow, bisexual.
B. FI. species 2 (Sarothra■).
1.	H. perforatum L. Common St. John’s-wort. Perennial. Stem
erect, 1-3 ft. high, 2-r.idged, much branched. Leaves linear or oblong,
obtuse, with translucent veins and dots. Cymes grouped in corymbs,
many-flowered. Flowers 1 in. in diameter. Sepals acute. Petals
much longer than the sepals, oblique at the tip and irregularly
fringed. A common v'eed in meadows and pastures E. and N.
Naturalized from Europe.
2.	H. gentianoides BSP. Orange Grass, Pineweed. Low (4-9
in. high), slender annual, w7ith erect, angled or almost winged, wiry
stem and branches. Leaves minute awl-shaped scales. Corolla about
\ in. in diameter, usually closing by or before midday. Sandy banks
and roadsides.VIOLET FAMILY
161
67. VIOLACEiE. Violet Family
Herbs, with simple, alternate leaves, with stipules. Calyx
of 5 persistent sepals. Corolla of 5 petals, somewhat zygo-
morphic; one petal with a spur. Stamens 5, short, the fila-
ments often united around the pistil (Fig. 24). Style generally
club-shaped, with a one-sided stigma, with an opening leading
to its interior. Pod 1-celled, splitting into 3 valves, each bear-
ing a placenta. The seeds are often dispersed by the splitting
of the elastic valves (Fig. 24).
Fig. 24. Viola tricolor
A, stamens and pistil; B, pistil with stamens removed; C, stamen; D, pod
split open, a, anther; c, connective; nci, nectarial appendage of stamen;
o, orifice in stigma; ov, ovary; s, stigma. (A, B, and C considerably
magnified)
VIOLA L.
Sepals ear-like at the base. Some of the petals often
bearded within, thus affording a foothold for bees, the lowest
one with a spur at the base. Stamens not very much united,
the two lowermost with spurs which reach down into the spur
of the lowest petal. Many species bear inconspicuous apeta-
lous flowers later than the showy ordinary ones, and produce
most of their seed from these closed, self-fertilized flowers.
§ 1. Apparently stemless perennials
1. V. pedata L. Bird-Foot Violet, Horseshoe Violet, Sand
Violet. Rootstock stout, upright, not scaly. Leaves roundish,
all palmately 5-9-parted into linear or linear-lanceolate divisions.
Flowers showy, about 1 in. broad, pale violet to whitish; petals not
bearded. Dry fields and hillsides.162
KEY AND FLORA
2.	V. cucullata Ait. Marsh Blue Violet. Leaves acute, except
the earliest ones. Petal-bearing flowers violet blue, with a darker cen-
ter ; peduncles usually longer than the leaves, the spur-bearing petal
smooth. Sepals narrowly lanceolate, with long ear-like appendages.
Cleistogamous flowers borne on erect or ascending peduncles. Cap-
sule not much longer than the sepals. Wet ground, common.
3.	V. papilionacea Pursh. Common Blue Violet, Dooryard
Violet. Plants usually strong and vigorous from a thick horizontal
rootstock, usually smooth. Leaves bright green, cordate at the base,
somewhat triangular or rounded and pointed. Scapes at the time of
flowering longer than the leaves. Petals dark violet-purple, white or
greenish-yellow at the base, the one with a spur often narrow and
boabshaped. Capsules from the cleistogamous flowers borne on hori-
zontal peduncles and often underground, but rising as they mature.
Very common about dwellings and gardens.
4.	V. palmata L. Early Blue Violet. Usually downy. Petioles
much longer than the blades; leaves, except the earliest ones, cordate-
ovate, with 5-9 variously toothed or cleft segments; the petioles and the
veins of the under surface very hairy. Scapes not usually longer than
the leaves. Sepals lanceolate, acute or taper-pointed. Petals violet-
purple, occasionally pale. Capsules from the cleistogamous flowers
borne on horizontal or deflexed peduncles. In dry, rich woodlands.
5.	V. sororia WiM, Woolly Blue Violet. In size and appear-
ance much like No. 3. Leaves ascending, mostly ovate or roundish-
ovate, pointed, cordate at the base, crenate, densely soft-hairy when
young. Peduncles hairy; petals varying from violet to lavender.
Cleistogamous flowers on short prostrate peduncles. Moist meadows
and rich woods.
6.	V. fimbriatula 8m. Ovate-Leaved Violet. Rootstock usu-
ally erect, at length long and stout. Petioles generally shorter than
the blades; leaves varying from ovate-lanceolate to oblong, usually
slightly crenate, truncate or almost cordate at the base. Petals blue,
bearded. Capsules of the cleistogamous flowers borne on erect
peduncles. In dry woods.
§ 2. Leafy-stemmed perennials
7.	V. pubescens Ait. Downy Yellow Violet. ’Soft-downy, 6-12
in. high. Basal leaves ovate-kidney-shaped, soon withering; stem
leaves broadly heart-shaped, toothed, pointed, with large stipules.
Flowers yellow, somewhat purple-veined, with a short spur. In dry
woods, common.
8.	V. scabriuscula Sehwein. Smootiiish Yellow Violet. Like
Ir. pubescens, but smaller, greener, and less downy. Stems decumbent
or ascending. Basal leaves broadly ovate, usually persistent throughPASSION FLOWER FAMILY
163
the flowering period. Flowers pale yellow, purple-veined. In moist
woods and thickets.
9.	V. canadensis L. Canada Violet. Stems tufted, very leafy,
smooth, 1 ft. or more high. Leaves heart-shaped, acute or taper-
pointed, serrate ; stipules lanceolate, entire. Flowers large and hand-
some. Petals white or nearly so, inside, the upper ones usually
violet-tinged beneath; lateral petals bearded. In rich woods, especially
of hilly regions.
10.	V. striata Ait. Striped Violet. Similar to V. canadensis,
but the stipules dentate, pinnately cut, or fringed. Petals cream-
colored, white, or bluish, distinctly veined. Moist woods and thickets.
§ 3. Leafy-stemmed, from an annual, biennial, nr occasionally short-
lived perennial root; stipules about as large as the blades of the
leaves.
11.	V. tricolor L. Pansy, Heart’s-Ease. Stem branching, angu-
lar, hardly erect. Leaves variable, more or less ovate, crenate or
crenate-serrate. Flowers large (often more than 1 in. across), flattish,
short-spurred, exceedingly variable in color. Cultivated from Europe.
12.	V. arvensis Murr. Field Pansy. Similar to V. tricolor, but
the whole plant smaller and more slender. Leaves narrow, often
lanceolate, the stipules dissected into narrow divisions. Petals all
yellow, equaling or shorter than the slender, pointed sepals. Com-
mon in old fields. Naturalized from Europe.
13.	V. Rafinesquii Greene. Wild Pansy. Annual, slender, often
branching from the base. Leaves small, the earlier ones roundish,
on slender petioles; the later ones obovate or narrower, tapering to
the base. Flowers small, yellowish-white to bluish-white. Petals
much longer than the linear sepals. Woods and fields.
68. PASSIFL0RACEA5. Passion Flower Family
SJirubs or herbs, climbing by axillary tendrils. Leaves al-
ternate, simple, mostly 3-lobed. Flowers axillary, on jointed
peduncles, solitary or few together, bisexual, actiuomorphic,
often showy. Calyx tube 4-5-lobed, persistent. Petals usually
5, inserted on the throat of the calyx tube, which is fringed
with a crown of 1-3 rows of long and slender filaments.
Stamens 5, their filaments united, and inclosing the stalk of
the ovary. Styles 1-5; ovary with 3-5 parietal placentae.
Seeds numerous ; fruit fleshy.1G4
KEY AND FLORA
PASSIFLORA L.
Characters of the family.
1.	P. incarnata L. Passion Flower. Perennial. Stem often
20-30 ft. long, somewhat angled or striate, smooth below, downy
above. Leaves broadly heart-shaped, palmately 3-5-lobed; the lobes
acute, finely serrate, usually heart-shaped at the base; petiole bear-
ing 2 oval glands near its summit. Flowers 2-3 in. wide, solitary;
peduncles 3-bracted, longer than the petioles; calyx lobes with a
small horn-like appendage on the back near the apex, white within.
Petals and crown purple and white. Fruit yellow, about the size and
shape of a hen’s egg, edible. Seeds with a pulpy aril. Common along
fence rows and embankments S.*
2.	P. lutea L. Yellow Passion Flower. Perennial. Stem
slender, smooth, G-10 ft. long. Leaves broadly heart-shaped, 3-lobed
at the summit, entire, often mucronate; stipules small; petioles
without glands. Peduncles longer than the leaves, usually in pairs.
Flowers greenish-yellow, A-f in. wide. Fruit purple, oval, A- in. long.
Woods and thickets &.*
69. BEGONIACEAt. Begonia Family
Chiefly perennial herbs or low shrubs, with fleshy or very
juicy stems. Leaves alternate, generally heart-shaped at the
base, often very unsymmetrical; stipules deciduous. Flowers
monoecious, in cymes or other clusters, on axillary peduncles.
Stamens many (Fig. 25). Pistillate flowers with the floral
envelopes borne on the ovary. Ovary 3-angled or 3-winged
(Fig. 25), very many-seeded.
BEGONIA L.
Flowers with the calyx and corolla of the same color, staini-
nate and pistillate ones both occurring in the same cluster.
Sepals usually 2. Petals 2 or in the fertile flowers 3 or 4,
sometimes wanting. Stamens many in a cluster, with short
filaments. Styles of the fertile flowers 3, often with long,
twisted stigmas (Fig. 25, C). The genus contains a great
number of species and varieties, cultivated from tropical or
subtropical regions, of which only a few of the commonest
are here described.1BEG0NIA FAMILY
165
1.	B. Rex Putz. Herb, apparently stemless or nearly so, from a
fleshy rootstock. Leaves large, taper-pointed, very unequally heart-
shaped; the margin sinuous, often bristly-fringed; upper surface
wholly silvery, or mottled silvery and dark green; lower surface green
or reddish, or of both colors. Flowers few, large (1 J-l J in. in diam-
eter) , varying from yellow to pinkish. Cultivated from the Himalayas.
Many varieties.
2.	B. manicata Brongn. Herb, with a short and fleshy stem.
Leaves very unevenly heart-shaped, taper-pointed; the margins
bristly-fringed and sometimes with very remote teeth; upper sur-
A: a, staminate flower; 6, pistillate flower. B, cross section of ovary ;
C, twisted stigmas, enlarged
face dark green, lower surface and petioles partly covered with long
fringed scales; stipules larger and fringed. Flowers flesh-colored,
handsome, in a loose panicle borne on a long peduncle. Cultivated
from Mexico.
3.	B. coccinea Hook. Tall, 3-10 ft. high, somewhat shrubby, often
with many erect, smooth stems from the same root. Leaves broadly
and unevenly lanceolate or ovate-lanceolate, half heart-shaped or
broadly one-eared at the base, acute, nearly or quite entire, smooth,
dull green above, sometimes tinged with red below. Peduncles several-
many-flowered, reddish, slender, somewhat nodding. Flowers showy,
medium-sized, scarlet. Fruit showy, scarlet, very broadly winged.
Cultivated from Peru. [Often called B. rubra.]166
KEY AND FLORA
4.	B. incarnata L. & O. Herbaceous or mainly so, rather tall
(2-4 ft.), stems clustered, slightly reclining, hairy when young, at
length smoother. Leaves broadly and very unequally ovate-lanceo-
late, tapering toward the tip but at the extremity somewhat blunt,
half heart-shaped at the base, somewhat lobed and sinuate-toothed,
rough-hairy above and below and on the petioles, dark green above
with coppery streaks along the veins. Flowers on short peduncles,
few, of medium size; beautiful rose-pink in the bud, becoming almost
white; thickly covered outside with soft, moss-like hairs. Cultivated
from Mexico. [Often called B. metallica.]
5.	B. semperflorens L. & O. Stems smooth, herbaceous, rather
fleshy, branching near the ground and reclining. Leaves obtuse or
nearly so, broadly ovate, somewhat unevenly heart-shaped or taper-
ing at the base, irregularly serrate or scalloped and wavy, smooth,
dark green, and very glossy above; stipules rather large, nearly ovate.
Flowers in small, axillary clusters near the top of the stem; whitish to
crimson, about 1} in. in diameter. Ovary in fruit very broadly winged.
An easily grown but homely species. Cultivated from S. Brazil.
70. CACTACE7E. Cactus Family
Plants usually with very fleshy and much thickened, often
globular or cylindrical, stems. Leaves usually wanting. Flowers
sessile, solitary, often very showy. Perianth epigynous, con-
sisting of several rows of sepals and petals. Stamens many,
with slender filaments, borne on the inside of the perianth
tube. Style 1; stigmas numerous; ovary 1-celled, many-
ovuled. Fruit a many-seeded berry.
I. OPUNTIA L.
Stem composed of a series of flattened joints, which are
usually leafless when full grown. Leaves very small, awl-
shaped, spirally arranged, appearing oil the young joints but
soon dropping off, with barbed bristles and sometimes spines
in their axils. Flowers yellow. Sepals and petals not much
united into a tube. Fruit often eatable.
1. 0. vulgaris Mill. Common Prickly Pear. Prostrate or nearly
so, pale green. Leaves about a in. long, rather scale-like; bristles
many, with few or no spines. Flowers 2 in. or more in diameter,CACTUS FAMILY
167
with about 8 petals. Fruit about 1 in. long, crimson when ripe, eat-
able. Dry rocks and sandy ground, from Massachusetts south along
the coast.
2.	0. Rafinesquii Engelm. Prostrate, green. Leaves J-J in. long,
awl-shaped, spreading; bristles often intermixed with a few small
spines and a larger one f-1 in. long. Flowers larger than in No. 1
and with 10-12 petals. Fruit about H in. long, much tapered at the
base. In poor soil.
3.	0. polyacantha Haw. Prostrate, light green. Leaves very small,
with bristles and 5-10 spines in their axils. Flowers 2-3 in. in diam-
eter. Fruit dry and spiny. Wisconsin, S. and W.
n. PHYLLOCACTUS Link.
Stems cylindrical when old, with long, flattened, fleshy but
leaf-like, sinuate or serrate branches. Flowers nearly or quite
regular, from the notches in the margins of the joints.
1. P. Ackermanni Solm. D. Flowers very showy, bright red.
Perianth tube shorter than the petals. Sepals scattered, small and
bract-like. Petals many, 2-3 in. long, widely spreading, somewhat
channeled, sharp-pointed. Cultivated from Mexico.
m. CEREUS L.
Stem more or less prismatic but strongly ridged, with bun-
dles of spines borne on the ridges ; sometimes prostrate or trail-
ing, sometimes erect, columnar, and 60 or 60 ft. high. Flowers
usually showy, borne on the sides of the stem, generally with
a rather long perianth tube, which is covered outside with scale-
like sepals, usually with tufts of wool in their axils. Petals
many, mostly long and spreading.
1.	C. speciosus Iv. Sell. Stems 2-3 ft. high, with 3-4 broad-winged
and sinuate ridges. Flowers open in the daytime and lasting several
days, red or crimson, very showy. Petals longer than the tube, stamens
white, drooping, very numerous. Commonly cultivated from Mexico.
2.	C. grandiflorus Mill. Night-Blooming Cereus. Stems long,
climbing by aerial roots, nearly cylindrical, but with 5 or more blunt
angles. Flowers very showy, opening only for one night, wilting early
in the morning, extremely fragrant. Sepals dull yellow'. Petals pearly
white, spreading, 6-8 in. long. Cultivated.from Mexico.168
KEY AND FLORA
71. 0NAGRACE2E. Evening Primrose Family
Herbs, rarely shrubs or trees. Leaves opposite or alternate,
without stipules. Flowers actinomorphic. Limb of the calyx
epigynous, 2-4-lobed. Petals 2-4, rarely wanting, quickly fall-
ing off. Stamens 1-8. Ovary usually 4-celled; style thread-
like ; stigma entire or 4-lobed; ovules 1 or more in the inner
angle of each cell. Fruit a capsule, berry, or drupe. Seeds
1 or more, smooth or hairy.
I. (ENOTHERA L.
Herbs, rarely shrubby. Leaves alternate. Flowers large, yel-
low, red, or purple. Calyx tube 4-angled. Petals 4. Stamens
8. Capsule usually 4-celled, many-seeded.
B. FI. species 1 (Onagra); species 2, 3 (Kneijfia) ; species 4
(Hartmannia); species 5 (Meijupti'flum.).
1.	(E. biennis L. Common Evening Primrose. Annual or bien-
nial. Erect and usually stout, 1-5 ft. high, stem usually simple,
more or less downy and hairy. Leaves lanceolate, acute or taper-
pointed, sessile or the lower ones petioled. Flowers bright yellow,
1-2 in. in diameter, opening in the evening. Pod oblong, narrowed
above, erect, nearly cylindrical. In dry soil.
2.	(E. pumila L. Small Sbndrops. Perennial. Stem erect, finely
downy, 4-24 in. high. Leaves usually smooth, entire, obtuse or nearly
so, the basal ones spatulate, those of the stem varying from oblanceo-
late to lanceolate. Spikes loose, nodding when young. Flowers -J-l
in. in diameter. Pods slightly glandular-downy, club-shaped, in.
long. In dry soil.
3.	(E. fruticosa L. Sundrops. Biennial or perennial. Stem erect,
often rather stout, 1-3 ft. high, downy or sometimes smooth. Leaves
lance-oblong, or in one variety linear or nearly so, usually minutely
toothed. Racemes often corymbed. Flowers open in the daytime,
showy, yellow, 1-2 in. in diameter. Pod nearly sessile, ellipsoidal,
with prominent ribs and strong wings. Dry soil, common.
4. (E. speciosa Nutt. Showy Primrose. Perennial. Stem downy,
erect or somewhat decumbent, 6 in.-3 ft. high. Leaves broadly
lanceolate to linear, sinuate-denticulate or sinuate-pinnatifid, 2-3 in.
long. Flowers opening in the daytime, few, 11-3J- in. in diameter,
white to pale pink. Pod strongly 8-ribbed. Prairies S.W.GIXSEXG FAMILY
169
5. CE. missouriensis Sims. Perennial. Stems low, decumbent, with
short, silky down. Leaves thick, from oval to linear, usually lanceo-
late, narrowed to a slender petiole, 2-(> in. long, entire or remotely
toothed. Flowers axillary, yellow, iS-ti in. in diameter. Capsule
orbicular, with broad wings. In dry soil SAW
II.	FUCHSIA L.
Herbs, shrubs, or trees. Leaves opposite or 3 in a whorl.
Flowers showy. Calyx colored, tubular-funnel-shaped, the
tube extending much beyond the ovary, the margin 4-lobed.
Petals 4, borne in the throat of the calyx. Stamens 8, project-
ing outside the corolla. Capsule berry-like, ellipsoidal, 4-angled.
1. F. macrostemma R. & P. Common Fuchsia, Ladies’ Ear-
drops. Smooth. Leaves slender-petioled, toothed. Flowers on long,
drooping peduncles from the axils of the leaves. Calyx tube oblong
or a short cylinder, not as long as its spreading lobes. Petals obovate
and notched, wrapped spirally around the projecting filaments and
style. Found in many varieties, sometimes the calyx white or nearly
so and the petals dark or with dark calyx and light petals. Culti-
vated from Chile.
III.	CIRC^A L.
Slender, erect herbs, with creeping rootstocks. Stem simple.
Leaves opposite, petioled. Flowers small, in terminal and
lateral racemes. Calyx tube ovoid, the limb 2-parted, reflexed,
deciduous. Petals 2, inversely heart-shaped, inserted with the
2 stamens under the margin of a disk which is borne on the
pistil. Ovary 1-2-eelled; style thread-like; stigma knobbed,
2-lobed ; ovules, 1 in each cell. Fruit ovoid, not splitting open,
covered with hooked bristles.
1. C. lutetiana L. Enchanter’s Nightshade. Stem 1-2 ft.
high, glandular-downy. Leaves ovate, faintly toothed, long-petioled.
Flowers J in. in diameter, white or pink, on slender pedicels, jointed
at the base. Damp, shaded places; very common.
72. ARALIACE2E. Ginseng Family
Herbs, shrubs, or trees. Leaves alternate, simple or com-
pound ; stipules united to the petiole or wanting. Flowers
regular, in umbels or heads. Limb of the calyx epigynous,170
KEY AND FLORA
very short. Petals 5, very deciduous. Stamens 5, filaments
bent inward, anthers versatile. Ovary 2-celled or several-
celled; styles or stigmas as many as the cells; ovules 1 in
each cell. Fruit a drupe or berry. [The English ivy, an
important member of the family, flowers too late for school
study.]
ARALIA L.
Perennial plants, with pungent or spicy roots, bark, and fruit.
Leaves once or more compound. Flowers more or less monoe-
cious, white or greenish, in umbels. Drupe, berry-like.
1.	A. hispida Vent. Bristly Sarsaparilla, Wild Elder. Stem
1-2 ft. high, rather shrubby below, with prickly bristles. Leaves
once or twice pinnate; leaflets ovate, acute, cut-serrate, and often
lobed. Peduncle bearing several umbels of cream-colored flow ers, in
a terminal corymb. Fruit blue-black. Dry fields and pastures E.
2.	A. nudicaulis L. Wild Sarsaparilla. Perennial herb. Roots
very long, somewhat fleshy, aromatic ; stem very short or none. Leaf
solitary, from a sheathing base, petioled, 6-12 in. long; compound in
threes, each division 3-5-pinnate ; leaflets oval or ovate, taper-pointed,
finely and sharply serrate, smooth above, often downy belowa Scape
nearly as long as the petiole, usually bearing 3 short, peduncled
umbels. Flow'ers greenish. Styles distinct. Fruit globose, black. In
rich woods.
73. UMBELLIFERJE. Parsley Family
Herbs, usually-with hollow, grooved stems. Flowers small,
generally in umbels. Limb of tlie calyx either wanting or
present only as a 5-toothed rim or margin around the top of
the ovary. Petals 5. Stamens 5, inserted on the disk, which
is borne by the ovary (Fig. 26). Ovary 2-celled and 2-ovuled
(Fig. 26), ripening into 2 akene-like carpels, which separate
front each other. Each carpel bears 5 longitudinal ribs, in
the furrows between which secondary ribs frequently occur.
On a cross section of the fruit oil tubes are seen, traversing
the interspaces between the ribs, and near the surface of the
fruit (Fig. 26, D). The seeds contain a small embryo, inclosed
in considerable endosperm. [The family is a difficult one,PARSLEY FAMILY
171
since the flowers are so much alike that the species are dis-
tinguished from each other mainly by minute characteristics
of the fruit.]
Annual, biennial, or perennial herbs. Stems erect or creep-
ing. Leaves simple, mostly linear and spiny-toothed. Flowers
white or blue, in dense, bracted heads or spikes, flowers brac-
teolate. Calyx teeth rigid, persistent. Petals erect, pointed.
Styles slender. Fruit top-shaped, scaly or granular; ribs
wanting; oil tubes usually 5, minute.*
A-D, Carum Carvi: A, flower; B, partly matured pistil; C, mature fruit;
D, cross section of fruit. E, fruit of parsnip; F, fruit of carrot, c, carpels;
cp, carpophore, or stalk to which ripe carpels are attached; d, disk; o, oil
tubes; oi\ ovary; s, stigmas. (A-D, after Schnizlein; E, after Bischoff)
1. E. yuccifolium Michx. Button Snakeroot, Rattlesnake
Master. Perennial. Stem erect, branched above, striate, -covered
with a bloom, 2-3 ft. high. Leaves linear, often 2 ft. or more in
I. ERYNGIUM L.
s
s.
Pig. 26. Flower and fruit of Umbelliferos172
KEY AND FLORA
length, rigid, covered with abloom, parallel-veined, fringed with white
bristles. Bracts shorter than the heads, entire; braetlets similar
but smaller. Flowers white. Fruit scaly. In damp soil.*
H. SANICULA L.
Slender, erect, perennial herbs. Rootstock short, stout,
creeping. Leaves palmately cut. Umbels small, somewhat
globular, irregularly compound ; bracts leafy ; braetlets few;
flowers bisexual or staminate, greenish or yellowish. Calyx
teeth as long as the small petals, sharp-pointed. Fruit ovoid,
covered with hooked prickles, ribless, each carpel with 5 oil
tubes.
1.	S. marilandica L. Sanicle, Black Snakeroot. Perennial.
Stem rather stout, 1-4 ft. high. Leaves 3-7-parted, the divisions
irregularly serrate or dentate and often cut. Flowers bisexual and
staminate, the latter in separate heads. Petals greenish-white, very
small. Styles slender, recurved, and longer than the prickles of the
fruit. Rich woods.
2.	S. gregaria Bicknell. Clustered Snakeroot. Stems gener-
ally clustered, 1-3 ft. high. Leaves 5-divided, obovate-wedge-shaped
to lanceolate. Some of the staminate flowers in separate heads.
Petals yellow, much longer than the calyx. Styles longer than the
prickles of the fruit. Woods and thickets.
3.	S. canadensis L. Short-Styled Snakeroot. Leaves peti-
oled, 3-5-divided. Staminate flowers never in separate heads. Styles
shorter than the prickles of the fruit. In woodlands.
III. ERIGENIA Nutt.
A little smooth plant, with a slender, unbranched stem, from
a deep, nearly globular tuber. Leaves 1 or 2, twice or thrice
compound in threes. Flowers few, small, in an imperfect
leafy-bracted umbel. Calyx teeth wanting. Petals obovate or
spatulate. Fruit smooth, roundish, notched at both ends, the
two carpels touching only at top and bottom, each with 5
slender ribs.
1. E. bulbosa Nutt. Harbinger or Spring, Turkey Pea, Pep-
per-and-Salt. Stem scape-like, with a leaf which forms an invo-
lucre to the flower cluster. Petals white, anthers brown-purple. A
pretty, though inconspicuous plant; welcomed as one of the earliest
spring flowers S.PARSLEY FAMILY
173
IV.	OSMORHIZA Raf. (WASHINGTONIA)
Perennials, springing from stout, aromatic roots. Leaves
compound in tlirees. Flowers white, in compound umbels.
Calyx teeth wanting. Fruit linear or nearly so, tapering at
the base, with 5 equal bristly ribs, without oil tubes.
1.	0. Claytoni Clarke. Hairy Sweet Cicely. Rather stout and
hairy, especially when young, lj-SJ ft. high. Lower leaves on long-
petioles, large, twice compound in threes, the divisions ovate or oval,
cut-toothed; upper leaves nearly sessile, less compound. Umbels with
long peduncles and spreading rays. Style and its enlarged base some-
what conical. Root nauseous. Rich woods.
2.	0. longistylis DC. Smooth-Leaved Sweet Cicely. Much
like No. 1 in general appearance. Smooth or nearly so. Style rather
thread-like. Root of a pleasant aromatic flavor (as is also the fruit).
Woods.
Caution. So many plants of this family have actively poisonous
roots and foliage that it is unsafe for any one but a botanist, who
can distinguish the poisonous species from the harmless ones, to taste
them.
V.	CARUM L.
Herbs, with slender, smooth stems. Leaves pinnately com-
pound, smooth. Umbels compound. Flowers white or yellow-
ish. Calyx teeth minute. Fruit smooth, oblong or ovate, with
thread-like ribs ; oil tube single in the intervals between the
ribs; base of the styles thickened into a conical mass.
1. C. CarviL. Caraway. Perennial. Leaves large, with the leaf-
lets cut into numerous thread-like divisions. Flowers white. Fruit
aromatic, used somewhat in this country and more in N. Europe for
flavoring cookies, bread, etc. Introduced from Europe.
VI.	ZIZIA Koch.
Smooth perennials. Leaves generally as in Thaspium. In-
volucre wanting; involucels of small bractlets. Umbels com-
pound. Flowers yellow. Calyx teeth prominent. Fruit more
or less ovoid, smooth, with thread-like ribs ; oil tubes large and
solitary between the ribs, and a little one in each rib ; the
central fruit of each umbellet sessile.174
KEY AND FLORA
1. Z. aurea Koch. Meadow Parsnip, Golden Alexanders.
Smooth, stem erect, 1-2 ft. high. Basal leaves mostly heart-shaped
and serrate; stem leaves usually once compound in threes. Flowers
deep yellow. Fruit between globose and ovoid, about £ in. long; all
the ribs generally winged. Woods and thickets.
VII. THASPIUM Nutt.
Perennial herbs. Stem erect. Leaves 1-2, compound in
threes. Umbels compound; involucre and involucels usually
wanting. Flowers yellow or purple. Calyx teeth small, acute.
Fruit ovoid or oblong, somewhat laterally compressed ; carpels
smooth, strongly ribbed ; oil tubes between the ribs.*
1. T. barbinode Nutt. Hairy Meadow Parsnip. Stem erect,
branching above, downy at the nodes, 2-7 ft. high. Leaves petioled,
slightly downy; leaflets mostly thin, ovate, toothed, incised or lobed
toward the apex, entire toward the base. Umbels long-peduncled,
few-rayed. Fruit oblong; lateral and central ribs strongly winged.
Along streams.*
Vm. LOMATIUM Raf.
Perennial herbs, appearing stemless. Roots thickened. Leaves
dissected. Flowers white or yellow, in compound umbels, with
no general involucre. Calyx teeth usually wanting. Fruit
orbicular, oval or oblong, much flattened dorsally, the lateral
ribs extended into broad wings ; oil tubes 1-4 on the intervals
between wings and 2-6 on the junctions of the carpels.
1.	L. orientale Coult. & Rose. White-Flowered Parsley.
Downy, with peduncles 3-8 in. high. Leaves twice pinnate, the
segments oblong or ovate, generally cut into rather obtuse linear or
nearly linear lobes. Bracts of the involucels lanceolate, with thin
membranous margins. Flowers white or pinkish. Fruit oval or
round, notched at the base, smooth; oil tubes solitary in the inter-
vals between ribs. Dry soil W.
2.	L. daucifolium Coult. & Rose. Carrot-Leaved Parsley.
Leaves finely dissected into short linear or thread-like segments.
Petals yellow. Fruit oval, with prominent dorsal ribs. Prairies W.
IX. PASTINACA L.
A tall, smooth biennial, with a stout, grooved stem. Leaves
pinnate. Flowers yellow, in large umbels, with hardly anyDOGWOOD FAMILY
175
involucre. Calyx teeth wanting. Fruit oval, very flat, with a
thin wing; oil tubes single, running the whole length.
1. P. sativa L. Common Parsnip. Cultivated from Europe for
its large, conical, sweet and edible roots. Also introduced in waste
places.
X. HERACLEUM L.
A stout perennial, with the very large leaves compound in
threes. Umbels large, compound, with the involucels many-
leaved. Petals white, inversely heart-shaped, the outer ones
usually 2-cleft and larger. Calyx with 5 small teeth. Fruit
tipped with a thick, conical enlargement of the style, with
three blunt ribs on the outer surface of each carpel and a large
oil tube in each interval between the ribs. Seeds flat.
1. H. lanatum Miefcx. Cow Parsnip. Stem grooved and woolly,
4-8 ft. high. Leaflets petioled, broad, deeply and irregularly toothed.
XI. DAUCUS L.
Annual or biennial, bristly-hairy herbs. Leaves pinnately
twice or more compound, the divisions slender. Umbels com-
pound, many-rayed. Flowers small, white. Calyx teeth slen-
der or wanting. Petals notched, the point bent inward, often
unequal. Fruit ovoid or ellipsoid, with rows of spines.
1. D. Carota L. Common Carrot. Erect, 1—3 ft. high, with a
conical, fleshy, orange-colored root. Lower and basal leaves 2-3-
pinnate. Central flower of each umbel and sometimes of each um-
bellet larger and very dark purple, with the corolla irregular. Cul-
tivated from Europe for the edible roots; also introduced in pastures
and meadows and along roadsides E.
74. CORNACEiE. Dogwood Family
Shrubs or trees, rarely herbs. Leaves opposite or alternate,
without stipules. Flowers small, actinomorphic, variously
clustered. Limb of the calyx epigynous, very short. Petals
4-5, borne on the margin of a disk on top of the ovary.
Stamens 4-5, inserted with the petals. Ovary 1-4-celled, with
one ovule in each cell; style 1. Fruit (in our species) a 1-2-
celled and 1-2-seeded drupe.176
KEY AND FLORA
I. CORNUS L.
Trees, shrubs, or herbs. Leaves usually opposite. Flowers
in forking cymes, or in umbels or heads, each with an invo-
lucre, white or yellow. Calyx teeth 4. Petals 4. Stamens 4.
Ovary 2-celled. Drupe ovoidal or ellipsoidal, the stone
2-celled.
1.	C- canadensis L. Dwarf Cornel, Bunchberry, Pudding
Berry. Stem herbaceous, excepting at the base, low (3-9 in.), and
unbranclied. Rootstock rather woody, slender, and creeping. Leaves
in wliat appears to be a whorl of 4 or 6 at the summit of the stem,
sessile, ovate, oval or nearly so, acute at each end, entire, smooth or
very slightly downy. Flower stalk slender, ^-1| in. long, with a
whorl of 1-li large, white, petal-like bracts, forming an involucre
round the small head of greenish flowers; the head with its invo-
lucre appearing to others than botanists like a single flower. Fruit
nearly spherical, scarlet, about } in. in diameter, in “a close cluster,
sweet and eatable, though rather insipid. Damp woods, especially If.
2.	C. florida L. Flowering Dogwood. Small trees; bark rough,
black. Leaves opposite, petioled, ovate to ovate-lanceolate, entire,
green and shining above, paler and often downy beneath. Flowers
small, greenish, Jn heads which are subtended by 4 large, white or
pink, inversely heart-shaped bracts, thickened and greenish at the
notch. Fruit ovoid, bright red. In rich woods S. and E.*
3.	C. circinata L’Her. Round-Leaved Dogwood. A shrub 3-10
ft. high, with green, warty twigs. Leaves petioled, roundish-oval,
contracted to an abrupt point, entire, usually rounded or truncate
at the base, pale and soft-downy beneath. Elowers in flat cymes,
11-2.1 in. in diameter. Fruit globose, light blue, ^ in. or less in
diameter. Thickets often in rocky soil X. and along Allegheny
Mountains.
4.	C. Amomum Mill. Kinnikixnik. A shrub 6-10 ft. high; twigs
purple, downy when young. Leaves opposite, petioled, ovate or ob-
long, taper-pointed, smooth above, silky-downy below. Flowers white,
in rather close cymes. Fruit blue, stone somewhat oblique. In low
woods.*
5.	C. asperifolia Michx. IIougii-Leayed Dogwood. A shrub
H-12 ft. high; twigs slender, reddish-brown, often warty, densely
downy when young. Leaves opposite, short-petioled, lance-ovate or
oblong, acute or taper-pointed, with rough down above, downy-woolly
below. Cymes flat, spreading, the peduncle and branches covered
with rough down. Flowers white. Fruit white or pale blue, stone
depressed-globose. In dry woods.*PYROLA FAMILY
177
6.	C. stolonifera Michx. Red Osier Dogwood. A shrub 3-15 ft.
high, with smooth, reddish-purple bark on all the younger twigs;
spreading by suckers from the base and therefore the stems usually
clustered. Leaves on rather slender petioles, acute or taper-pointed,
rounded or tapered at the base ; covered, at least beneath, by very fine,
closely appressed hairs. Fruit white or nearly so, globose, J in. or
more in diameter. Common in wet ground, especially X.
7.	C. alternifolia L. f. Alternate-Leaved Dogwood. A shrub or
small tree; twigs greenish, striped. Leaves alternate, often clustered
at the ends of the twigs, long-petioled, oval, acute at the apex and
often at the base, minutely toothed, pale and covered with fine, ap-
pressed hairs beneath. Cymes loose and open; flowers white. Fruit
deep blue. Banks of streams.*
II. NYSSA L.
Trees or shrubs. Leaves alternate, petioled* entire or few-
toothed. Flowers somewhat monoecious or dioecious, the
staminate in many-flowered heads or cymes, the pistillate in
small clusters or solitary. Calyx tube 5-toothed or truncate.
Petals minute or wanting. Stamens 5-10. Ovary 1-celled,
1-ovuled; style long and recurved. Fruit a 1-seeded drupe.
1.	N. sylvatica Marsh. Black Gum. A tree with widely spread-
ing branches and dark, rough bark ; wood light-colored, very tough ;
base of trunk often enlarged. Leaves often clustered at the ends of
the twigs, oval or obovate, taper-pointed or obtuse at the apex, entire,
smooth and shining above, downy beneath, becoming bright red in
autumn. Staminate flowers in heads; pistillate flowers 3-10, in a
long-peduncled cluster. Fruit ovoid, dark blue or nearly black, I in.
long; stone slightly ridged. In rich, wet soil S. and E.*
2.	N. aquatica L. Tupelo. A large tree, similar to the preceding.
Leaves long-petioled, oval or ovate, acute at each end, entire or
coarsely toothed, the lower sometimes heart-shaped, smooth above,
downy beneath, 1-8 in. long. Staminate flowers in heads; pistillate
flowers on long peduncles, solitary. Fruit ovoid, dark blue; stone
sharply ridged. In swamps S. and E.*
75. PYROLACEiE. Pyrola Family
Perennial herbs, evergreen or else pale and without chlo-
rophyll. Petals usually free from each other and falling off
separately after flowering. Stamens hypogynous, the anthers178
KEY AND FLORA
without appendages and opening by pores or by a transverse
slit. Fruit a capsule containing a great number of very small
seeds.
I. CHIMAPHILA Pursh.
Low plants, nearly herbaceous, with reclining stems, from
long, horizontal, underground shoots. Leaves opposite or
whorled, leathery, shining, evergreen, on short petioles.
Flowers fragrant, white or purplish, on a corymb or umbel
which terminates the stem. Calyx 5-cleft or 5-parted, per-
sistent. Petals 5, concave, roundish, spreading. Stamens 10,
the filaments enlarged and downy in the middle, the anthers
somewhat 4-celled, opening when mature by pores at the
outer end. Style top-shaped, nearly buried in the top of the
globular ovary^ Capsule erect, 5-celled.
1.	C. umbellata Nutt. Prince’s Pine, Pipsissewa. Branches
leafy, 4-12 in. high. Leaves spatulate or wedge-oblanceolate, obtuse
or nearly so, sharply serrate, very green and glossy. Flowers sev-
eral, umbeled or somewhat corymbed, white or pinkish, the anthers
violet. Dry woods, especially under pine trees.
2.	C. maculata Pursh. Spotted Wintergkeen. Much resem-
bles No. 1, but has only scattered teeth on the leaves, which are
mottled with white on the upper surface and are often broad or
rounded at the base. Dry woods.
II PYROLA L.
Biennial or perennial, almost woody herbs; rootstocks slen-
der and creeping. Leaves mostly basal, with broad petioles,
evergreen. Flowers in racemes, nodding, on a bracted scape.
Sepals 5. Corolla usually globose, of 5 free or nearly free,
roundish petals. Stamens 10, in pairs opposite the petals,
hypogynous; anthers as in Chimaphila. Capsule globose,
5-	celled, splitting into 5 valves, the latter usually with downy
edges.
1.	P. elliptica Nutt. Shin Leaf. Scape 5-10 in. high. Leaf blades
obovate-oval or elliptical, rather thin, dark green, faintly scalloped,
almost always longer than their margined petioles. Flowers greenish-
white, very fragrant. Rich, usually dry, woods, especially N.
2.	P. americana Sweet. Round-Leaved Wintergrf.en. Scape
6-	20 in. high. Leaf blades roundish or oval, leathery, shining above,HEATH FAMILY
179
faintly scalloped, often rounded at the base or almost heart-shaped,
usually shorter than the slightly margined petioles. Flowers white,
very fragrant. Varies greatly. Usually in dry woods X.
m. MONOTROPA L.
Leafless, simple, erect, white, brown, or red root parasites
or saprophytes or fed by slender fungus threads which cluster
on the roots. Stem scaly, the upper scales often passing into
bracts. Flowers solitary or in spikes or racemes. .Sepals or
bracts 2-5, erect, deciduous. Petals 4 or 5, erect or spreading.
Stamens 8or 10,hypogynous,the filaments awl-shaped; anthers
kidney-shaped. Ovary 4-5-celled; style simple ; stigma disk-
like, with 4-5 rays.
B.F1. species 2 (Hypopitys).
1.	M. uniflora L. Indian- Pipe. Stem smooth, fleshy, 4-6 in. high.
Bracts ovate or lanceolate. Flower single, tubular, J-l in. long, inodor-
ous. Stamens a little shorter than the petals. Capsule angled, I-f in.
long. Whole plant waxy-white, turning black in drying. In moist,
shady woods N. and E.*
2.	M. Hypopitys L. Pinesap. Stems single or clustered, white
or reddish, 4-8 in. high. Bracts ovate-lanceolate. Flowers several,
in a scaly raceme, fragrant, |-j in. long. Capsule oval, \ in. long.
In dry, shady woods, especially under oaks or pines.*
76. ERICACE.2E. Heath Family
LTsually shrubs or slightly shrubby plants. Leaves simple,
generally alternate. Corolla commonly aetinomorpkic, 4-5-
cleft, sometimes choripetalous. Stamens hypogynous, distinct,
as many or twice as many as the petals; the anthers mostly
opening by a hole at the end. Ovary usually with as many
cells as there are corolla lobes ; style 1. Seeds small, with
endosperm.
A
Shrubs or small trees. Calyx free from the ovary. Corolla hypogymatu,
usually sympetalous.
Shrubs or small trees, with showy flowers. Anthers not held
down in pockets in the corolla.	Rhododendron, I180
KEY AND FLORA
Shrubs with showy flowers. Anthers at first held in pocket-
like depressions in the corolla.	Kalmia, II
Shrubs with small, mostly white, urn-shaped flowers.
Lyonia, III
A prostrate plant, hardly at all shrubby. Leaves rather large,
often 1J- in. wide, and veiny.	Epigaea, IV
A trailing plant with small (about J in. wide), thick, evergreen
leaves.	Arctostaphylos, V
B
Shrubs. Flowers epigynous; corolla sympetalous. Fruit a true berry or
resemblbxj one.
Fruit a berry-like drupe, with 10 nutlets which resemble seeds.
Gaylussacia, VI
Fruit a berry with many small seeds.	Vaccinium, VII
I. RHODODENDRON L.
Shrubs, often much branched. Leaves alternate, thin,
deciduous. Flowers very showy, in terminal umbels, from
scaly buds which became well developed the previous season.
Calyx very small, 5-parted. Corolla bell-shaped, the tube
long and slender, the limb spreading and somewhat one-sided.
Stamens 5 or 10, declined; anthers awnless. Style long and
slender, declined ; stigma knobbed. Capsule oblong or linear,
5-celled, many-seeded; seeds very small, scale-like.
1.	R. viscosum Torr. Swamp Honeysuckle, Swamp Pink. A
shrub, 4-6 ft. high; branches hairy. Leaves obovate, leathery,
mucronate at the apex, mostly smooth above, downy on the veins
beneath; petioles very short. Flowers appearing later than the
leaves, white, fragrant, 11-2 in. long; tube long, glandular-viscid.
Capsule erect, in. long, bristly. In swamps.*
2.	R. nudiflorum Torr. Wild Honeysuckle, Election Pink.
A branching shrub, 4-6 ft. high ; twigs smooth or with a few coarse
hairs. Leaves obovate or oblong, ciliate-serrate, dow ny, becoming
smooth above; petioles short. Flowers appearing with or before the
leaves, pink or white, sometimes yellowish, fragrant, 1-2 in. wide,
tube downy but not glandular. Capsule erect, linear-oblong, |-} in.
long. Swamps and banks of streams; flowers extremely variable in
size and color.*HEATH FAMILY
181
H. KALMIA L.
Erect and branching shrubs. Leaves alternate, opposite
or in threes, entire, leathery, evergreen. Flowers showy, in
corymbs, or 1-3 in the axils. Calyx 5-parted. Corolla flat-
bell-shaped or wheel-shaped, 5-lobed. Stamens 10, the anthers
placed in pouches in the corolla, filaments straightening elas-
tically at maturity and so bringing the anthers in contact with
any large insect-visitor. Style long and slender. Capsule glo-
bose, 5-celled, many-seeded.
1.	K. latifolia L. Calico Bush, Mountain Laurel. A shrub,
4-10 ft. high. Branches stout, smooth. Leaves mostly alternate,
petioled, elliptical or oval, acute at each end, smooth and green on
both sides. Corymbs terminal, compound. Flowers white to rose
color, showy, 1 in. broad. Calyx and corolla glandular; pedicels
long, slender, sticky-glandular, erect in fruit; calyx and style per-
sistent. Shady banks on rocky or sandy soil.*
2.	K. angustifolia L. Sheep Laurel. Lambkill. A shrub, 1-3 ft.
high, with smooth, nearly erect branches. Leaves petioled, opposite
or in threes, oblong, obtuse at both ends, dark green above, paler
beneath. Corymbs lateral, glandular. Flowers purple or crimson,
4-y in. broad. Pedicels slender, recurved in fruit. Calyx downy, per-
sistent. Style persistent; capsule depressed-globose. On hillsides;
abundant northward.*
IE. LYONIA Nutt.
Shrubs or small trees. Leaves alternate, persistent or fall-
ing late. Flowers mostly white, in panicles, racemes, or umbels.
Calyx 5-parted; corolla urn-shaped. Stamens 10; filaments
hairy, often with teeth or appendages ; anthers oblong or ovoid.
Capsule globose or nearly so, 5-angled. Seeds sawdust-like,
with a loose outer coat.
B. FI. species 1 (Pieris) ; species 2 (Xolisma).
1.	L. mariana I). Don. Staggerbush. A smooth shrub, '20-40
in. high. Leaves oval or oblong, smooth above, slightly downy on
the veins beneath. Flowers nodding, on leafless shoots. Filaments
with 2 teeth near the apex. Capsule ovoid-pyramidal, truncate at its
apex. Low, sandy soil. Foliage said to be poisonous.
2.	L. ligustrina DC. Male Berry. A minutely downy shrub, 11-10
ft. high. Leaves varying from obovate to ovate, finely serrate or entire.
Bacemes usually leatless, crowded in terminal panicles. Filaments flat,
without appendages. Capsule globose. Moist thickets and swamps.182
KEY AND FLORA
iv. epiga:a l.
Prostrate or trailing shrubs. Stems rusty-downy, 6-12 in.
long. Leaves alternate, leathery, evergreen. Flowers in
bracted, terminal, close racemes or clusters. Calyx 5-parted,
persistent. Corolla salver-shaped, 5-lobed. Stamens 10, about
the length of the corolla tube. Ovary 5-lobed; style colum-
nar ; stigma 5-lobed. Fruit a globose, hairy, 5-celled, many-
seeded capsule.*
1. E. repens L. Ground Laurel, Trailing Arbutus, May-
flower. Stems creeping, the young twigs ascending. Leaves oval
or somewhat heart-shaped, entire, netted-veined, smooth above,
rough-hairy beneath; petioles short, rough-hairy. Racemes shorter
than the leaves. Flowers white to bright pink, J in. broad, very
fragrant. In dry woods, often covering considerable areas.*
V. ARCTOSTAPHYLOS Adans.
Shrubs. Leaves alternate, evergreen. Flowers pinkish or
nearly white, in terminal, bracted racemes. Calyx 4-5-parted,
persistent. Corolla 4-5-lobed, the lobes recurved. Ovary 5-
10-celled, each cell containing 1 ovule. Fruit a berry-like
drupe, witli 5-10 nutlets.
1. A. Uva-ursi Spreng. Bearberry. In trailing clumps, the
branches 1-2 ft. high. Leaves evergreen, finely woolly, obovate or
spatulate, entire, very leathery. Racemes few-flowered, very short.
Corolla urn-shaped, the teeth hairy within. Berry red, ^ in. in
diameter. Rocks and dry hilltops, especially N.
VI. GAYLUSSACIA HBK.
Low, branching shrubs, mostly resinous-dotted. Leaves
serrate or entire. Flowers small, white or pink, in lateral,
bracted racemes, nodding; pedicels usually 2-bracteolate.
Calyx tube short, obconic, the lobes persistent. Corolla ovoid
to bell-shaped, 5-lobed, the lobes erect or recurved. Stamens
equal, usually included; anthers awnless. Fruit a 10-seeded,
berry-like drupe.*
1. G. frondosa T. & G. Tangleberry, Dangle berry. An erect
shrub, 1-fl ft. high; branches spreading, slender, gray, slightly downy.
Leaves entire, oblong or obovate, obtuse, thin, smooth and green
above ; paler, downy, and with resinous dots, beneath; petioles short.HEATH FAMILY
183
Racemes few-flowered. Corolla small, greenish-pink, short-bell-shaped;
bracts small, oblong, shorter than the pedicels. Berry depressed-
globose, dark blue, with bloom, sweet, about } in. in diameter. On
low ground.*
2. G. baccata K. Koch. Huckleberry. A much-branched, stiff
shrub, 1-3 ft. high, slightly downy when young. Leaves oval or
oblong, rarely obovate, obtuse or nearly so, entire, covered when
young with little resinous particles. Flowers in short, one-sided
racemes. Corolla at first conical-ovoid, becoming afterward nearly
cylindrical, pink or reddish. Fruit (in the typical form) black, with
no bloom, sweet; the seed-like nutlets rather large. Woods and
pastures in sandy soil.
VH. VACCINIUM L.
Shrubs or small trees. Leaves entire or serrulate, often
leathery and evergreen. Flowers terminal or lateral, clus-
tered or solitary, nodding. Pedicels 2-bracteolate. Calyx tube
globose or hemispherical, 4-5-lobed, persistent. Corolla urn-
shaped, cylindrical or bell-shaped, 4-5-lobed. Stamens twice
as many as the lobes of the corolla; anthers awned or awnless.
Ovary 4-5-celled, each cell partially divided by a partition,
which makes the ovary appear S-10-eelled; style slender ;
stigma simple. Fruit a many-seeded berry.*
B. FI. species 1 (Batodendrori) ; species 2 (Poly cod ium);
species 6 (Oxycoccus).
1.	V. arboreum Marsh. Farki.eberry. Tree-like, sometimes 30 ft.
high; bark gray; twigs slender, smooth or downy. Leaves decidu-
ous, ovate or oval, mucronate, entire or glandular-dentate, leathery,
green above, often slightly downy beneath. Racemes with leaf-like
bracts; pedicels slender, drooping. Corolla campanulate, white.
Anthers included; style projecting. Berry globose, black, mealy,
ripening in winter. Common in dry, open woods.*
2.	V. stamineum L. Deerberry, Squaw Huckleberry. An
erect shrub, 3-10 ft. high ; branches widely spreading, twigs smooth
or minutely downy. Leaves deciduous, oval or oblong, acute or
taper-pointed, at the apex, obtuse or slightly heart-shaped at the
base, firm, smooth, and green above, pale and slightly downy be-
neath, petioled. Racemes with leaf-like bracts. Flowers numerous,
drooping, on jointed, slender pedicels. Corolla bell-shaped, purplish-
green, 2-awned anthers and style projecting. Berry globose or pear-
shaped, inedible. Dry woods.*
3.	V.pennsylvanicumLam. Dwarf Blueberry,Low Blueberry.
Low (usually 6-12 in. high, sometimes 2 ft. high) and smooth, with184
KEY AND FLORA
warty green branches. Leaves oblong or oblong-lanceolate, sharply
serrate, with little bristle-pointed teeth, both sides smooth and shin-
ing except for down occasionally on the midrib and veins below,
pointed at both ends. Flowers few in a cluster, longer than their
minute pedicels. Corolla oblong, bell-shaped, a little narrovred at
the throat, white or pinkish. Berry blue, with much bloom, ripening-
earlier than the other eatable species, sweeter than No. 5 but not so
high-flavored. In dry or sandy soil, especially N.
4.	V. vacillans Kalm. Late Low Blueberry. Alow, stiff, smooth
shrub, 1-3 ft. high; branches yellowish-green. Leaves obovate or oval,
pale or dull green, smooth beneath, entire or nearly so. Flowers green-
ish-yellow or somewhat pink. Berries late-ripening, blue, with some
bloom, sweet. Dry, especially sandy,jsoil.
5.	V. corymbosum L. High-Bush Blueberry. An erect shrub,
6-12 ft. high; branches stiff, young twigs minutely warty. Leaves
deciduous, oval to ovate-lanceolate, acute, margins bristly, serrulate,
smooth or downy, short-petioled. Racemes numerous, appearing with
or before the leaves. Bracts oval or oblong, deciduous. Flowers white
or pink. Corolla almost as long as the pedicel, cylindrical. Berry
globose, blue or black, flavor slightly acid, pleasant. Common in
woods and thickets. Whole plant extremely variable.*
6.	V. macrocarpon Ait. Cranberry. Stems creeping, thread-like,
1-3 ft. or more in length, the branches not quite erect, sometimes
8 in. high. Leaves usually oval or oblong, obtuse, thickish, ever-
green, the younger ones with the margins somewhat rolled under.
Flowers nodding. Petals strongly reflexed, deep rose-red inside at
the base, pale pinkish or almost white at the tips. Stamens with
the filaments hardly as long as the anthers. Fruit red or reddish-
purple, ellipsoidal or nearly globose, very acid, much valued for sauce,
pies, and jellies. Common in peat bogs and wet meadows N.
77. PRIMULACEAi. Primrose Family
Herbs, with simple leaves, often most or all of them basal.
Flowers bisexual and actinomorphic, generally sympetalous.
Stamens commonly 5, inserted on the corolla, opposite its
lobes. Pistil consisting of a single stigma and style and a
(generally free) 1-celled ovary, with a free central placenta.
A
Leaves all basal.
(a) Segments of corolla not reflexed, throat open. Stamens in-
cluded.	Primula, IPRIMROSE FAMILY
185
(i) As in (a), but throat of corolla narrowed. Androsace, II
(c) Segments of corolla much reflexed. Stamens protruding.
Dodecatheon, YIII
B
Stems leafy, at least near the summit.
(a) Corolla yellow. Xo sterile appendages alternating with the
stamens.	Lysimachia.	Ill
(i) Corolla yellow. Sterile appendages alternating with the
stamens.	Steironema,	IV
(c) Corolla white. Stems with leaves mostly whorled near the
summit.	Trientalis, V
(rf) Corolla scarlet (sometimes white or blue). Stems low, leafy
throughout.	Anagallis,	VI
(e) Corolla inconspicuous, pink. Stems leafy, very short.
Centunculus, YII
I. PRIMULA L.
Low, perennial herbs, with much-veined basal leaves ; scapes
each bearing an umbel of flowers, which are often showy. Calyx
tubular, decidedly angled, 5-cleft. Corolla more or less salver-
shaped, with the tube widened above the insertion of the sta-
mens ; the 5 lobes of the limb often notched or cleft. Stamens
5, not protruding outside the corolla tube. Capsule egg-shaped,
splitting at the top into 5 valves, each of which may divide
in halves.
1.	P. grandiflora Lam. True Primrose. Leaves spatulate or
obovate-oblong. Flowers rising on separate slender pedicels from
the leaf axils. Corolla originally pale yellow, but varying to white,
red, and many intermediate shades, with a broad, flat limb. Culti-
vated from Europe.
2.	P. sinensis Sabine. Chinese Primrose. A rather coarse,
downy plant. Leaves round-heart-shaped, more or less lobed and
cut, long-petioled. Flowers large, in umbels, usually rose color or
white. Calyx large, inflated and conical. Cultivated as a house
plant from China.
II. ANDROSACE L.
.Small herbs, with clustered basal leaves. Flowers very small,
solitary or umbeled. Calyx 5-cleft, with a short tube. Corolla
salver- or funnel-shaped, contracted at the throat, its tube186
KEY AND FLORA
shorter than the calyx. Stamens 5, perigynous, not protrud-
ing from the tube of the corolla. Capsule 5-valved, few-many-
seeded.
1. A. occidentalis Pursh. Annual, smooth or nearly so. Scapes
usually clustered, 1-3 in. high, erect or ascending. Lobes of the
calyx becoming leafy. Corolla white, shorter than the calyx. In dry
soil W.
IU. LYSIMACHIA L.
Perennials, with opposite or whorled entire leaves, which
are often dotted. Calyx 5-6-parted. Corolla wheel-shaped,
with its divisions commonly nearly separate. Stamens gener-
ally somewhat monadelphous at the base.
B. FI. species 4 (' Naumburgia).
1.	L. quadrifolia L. Four-Leaved Loosestrife. Stem erect and
simple, 1-2 ft. high, hairy. Leaves whorled, most frequently in fours,
broadly lanceolate. Flowers small, axillary, and solitary, on long and
slender peduncles. Damp or sandy soil.
2.	L. terrestris BSP. Bulb-Bearing Loosestrife. Stems 1-2 ft.
high, finally branching, frequently producing bulblets in the leaf
axils after flowering. Leaves abundant, generally opposite, narrowly
lanceolate. Flowers small, pediceled, in a long, terminal raceme.
Low or swampy ground.
3.	L. Nummularia L. Moneywort. Stems creeping, smooth.
Leaves small, round or nearly so. Flowers solitary in the leaf axils,
yellow, J-l in. in diameter. Cultivated and escaping into moist
ground. Introduced from Europe.
4.	L. thyrsiflora L. Tufted Loosestrife. Stem simple, erect,
1-2 ft. high. Leaves all opposite and lanceolate except the lower
ones. Racemes spike-like, 1 in. or less long, borne in the leaf axils
near the middle of the stem. Flowers small, light yellow with black
spots. In swamps.
IV. STEIRONEMA Eat'.
Perennial herbs. Leaves opposite or whorled, simple, entire.
Flowers yellow, axillary or racemose, on slender peduncles.
Calyx tube 5-parted, persistent. Corolla 5-parted, wheel-shaped,
tube very short or none, the lobes denticulate at the apex, and
in the bud each one inclosing a stamen. Stamens 5, distinct
or slightly united at the base; sterile rudiments often alter-
nating with them. Ovary globose; style slender. Fruit a glo-
bose, 5-valved, few- or many-seeded capsule.*PRIMROSE FAMILY
187
1.	S. ciliatum Raf. Fringed Loosestrife. Stems erect, slender,
simple or branched, 1-3 ft. high. Leaves opposite^ ovate to ovate-
lanceolate, acute at the apex, rounded at the base; margins and
petioles hairy-fringed. Flowers solitary on axillary peduncles, f-1 in.
broad; petals broadly ovate or roundish, denticulate; calyx shorter
than the capsule. Woods and thickets.*
2.	S. lanceolatum Gray. Lance-Leaved Loosestrife. Steih
erect, 6-21 in. high. Leaves varying from lanceolate to oblong and
linear, petioled or almost sessile, acute or taper-pointed. Flowers
f-f in. in diameter. Capsule nearly as long as the segments of the
calyx. In moist ground and thickets.
3.	S. quadriflorum Hitchc. Linear-Leaved Loosestrife. Stem
erect, 1-sided, slender, 1-3 ft. high. Basal leaves oblong or linear-
oblong, on slender petioles; stem leaves, all but the lowest, nearly
or quite sessile, narrowly linear, 2-1 in. long, smooth and shining.
Flowers about J in. in diameter, often clustered in fours at the ends of
the branches. Corolla lobes pointed. Along streams, especially X.W
V.	TRIENTALIS L.
Low, smooth, perennial herbs, with slender, erect, un-
branched stems. Leaves lanceolate, ovate, or oblong, mostly
in a whorl at the summit of the stem. Flowers one or few,
terminal, on slender peduncles, small, white or pink. Sepals
narrow and spreading. Corolla wheel-shaped, with usually
7 taper-pointed segments. Ovary globose; style thread-like.
Capsule globose, many-seeded.
1. T. americana Pursh. Star Flower, Chickweed Winter-
green. Spreading by long and slender rootstocks; branches erect,
stem-like, 3-9 in. high. Leaves very thin, pale greeD, pointed at both
ends. Flow’ers white. Capsules white, marked off into polygonal
sections, each corresponding to 1 seed. Cold woods; common N.
VI.	ANAGALLIS L.
Annual or perennial herbs. Stems erect or diffuse. Leaves
opposite or whorled. Flowers axillary, peduncled. Calyx tube
5-parted, persistent. Corolla wheel-shaped, 5-parted, longer
than the calyx. Stamens 5, inserted on the base of the corolla;
filaments bearded. Ovary globose; style slender; stigma
knobbed. Fruit a many-seeded capsule, the top coming off
like a lid.*188
KEY AND FLORA
1. A. arvensis L. Poor Man’s Weatherglass, Pimpernel.
Annual; stem spreading, widely branched, 4-angled, smooth, 4-12
in. long. Leaves opposite, sessile, ovate, black-dotted beneath.
Flowers on peduncles longer than the leaves, nodding in fruit. Co-
rolla fringed with glandular hairs, longer than the acute calyx lobes,
bright red (sometimes white or blue), opening in sunshine. Capsule
globose, tipped by the persistent style. Introduced, and common in
fields and gardens.*
VII.	CENTUNCULUS L.
Small annuals, with alternate entire leaves. Flowers axil-
lary and solitary, inconspicuous. Calyx 4-5-parted. Corolla
4-5-cleft, shorter than the calyx, the tube urn-shaped. Stamens
4-5, perigynous, with short filaments. Capsule globose, many-
seeded, the top falling off as a lid.
1. C. minimus L. Chaffweed, False Pimpernel. Stems 1-G
in. high. Leaves spatulate or obovate, with short petioles. Flowers
small, pink, nearly sessile, parts of the perianth usually in fours.
Moist soil W.
VIII.	DODECATHEON L.
A smooth, perennial herb, with a cluster of oblong or spatu-
late basal leaves, fibrous roots, and an unbranched scape, leaf-
less except for an involucre of small bracts at the summit, with
a large umbel of showy, nodding flowers. Calyx deeply 5-cleft,
with reflexed, lanceolate divisions. Tube of the corolla very
short, the divisions of the 5-parted limb strongly reflexed.
Filaments short, somewhat united at the base; anthers long,
acute, and combining to form a conspicuous cone.
1. D. Meadia L. Shooting Star, Indian Chief. Corolla vary-
ing from rose color to white. In rich woods in most of the Middle
and Southern states. Often cultivated.
78. EBENACEiE. Ebony Family
Trees or shrubs. Leaves alternate, entire, pinnately veined,
without stipules. Flowers often dioecious. Calyx free from
the ovary, persistent. Stamens 2-4 times as many as the divi-
sions of the corolla. Ovary 3-12-celled; ovules 1 or 2 in each
cell. Fruit a berry. Mostly tropical plants.OLIVE FAMILY
189
DIOSPYROS L.
Flowers dioecious or somewhat monoecious, the staminate
ones in cymes, the pistillate ones axillary and solitary. Calyx
4-6-lobed. Corolla 4-6-lobed. Stamens in the staminate flowers
usually 16, in the pistillate ones 8, imperfect. Fruit large,
with the persistent calyx attached to its base, 4-8-seeded.
1. D. virginiana L. Persimmon. Trees, with rough, black bark, and
very hard wood. Leaves oval or ovate-oblong, acute or acuminate
at the apex, rounded or slightly cordate at the base, entire and dark
green, smooth above, pale and often downy beneath, short-petioled,
deciduous. Flowers yellowish-white, the parts mostly in fours. Fruit
globose, edible when ripe, very astringent when green; seeds large,
compressed, often wanting. Fruit ripening late in the fall. Common
in old fields and along roadsides S. and S.W.*
79. OLEACEIE. Olive Family
Shrubs or trees. Leaves opposite, simple or odd-pinnate,
without stipules. Flowers usually in forking cymes, small,
white, greenish or yellow, bisexual or unisexual. Calyx free
from the ovary, 4-lobed or wanting. Corolla hypogynous, regu-
lar, 4-parted or of 4 separate petals, sometimes wanting. Sta-
mens 2, borne on the petals or hypogynous. Ovary 2-celled.
Fruit 1-2-celled, each cell 1-seeded, rarely 2-seeded (in For-
sythia many-seeded).
I. FRAXINUS Tourn.
Deciduous trees. Flowers dioecious. Petals wanting (in our
species). Stamens 2, hypogynous. Fruit a 1-2-celled key, each
cell 1-seeded.
1.	F. americana L. White Ash. A large tree; bark rough, gray;
wood hard, strong, elastic; twigs and petioles smooth. Leaflets usu-
ally 7, ovate to ovate-lanceolate, taper-pointed at the apex, rounded
or obtuse at the base, entire or slightly serrate, smooth above, often
downy beneath, short-stalked. Flowers mostly dioecious. Calyx of the
pistillate flowers persistent. Key l)-2 in. long, winged only at the
apex; wing spatulate or oblanceolate. In rich woods and swamps.*
2.	F. pennsylvanica Marsh. Red Ash. A small tree ; bark rough,
dark gray; twigs and petioles densely velvety-downy. Leaflets 5-9,
oblong-ovate to ovate-lanceolate, taper-pointed at the apex, narrowed190
KEY AND FLORA
into a short stalk at the base, finely serrate, smooth above, velvety-
downy beneath. Calyx of the pistillate flowers persistent. Key lj-
2 in. long, the wing' somewhat extended along the sides, oblanceolate
or spatulate, often notched. Swamps and moist soil.*
3.	F. caroliniana Mill. Wateji Ash. A small tree; wood soft,
light, and weak; twig's smooth or downy. Leaflets 5-7, ovate or ellip-
tical, acute at the apex, acute or obtuse at the base, entire or slightly
serrate, smooth or slightly downy, stalked. Flowers dioecious. Calyx
persistent. Key often 3-angled or 3-winged, wings running nearly to
the base, oblong or oval, pinnat.ely veined. In swamps and wet soil.*
4.	F. quadrangulata Michx. Blue Ash. A large tree, with wood
heavy, but not as tough as No. 1; the most vigorous twigs usually
square. Leaflets 7-9, with short stalks, somewhat ovate or lanceolate,
acute, sharply serrate. Fruit winged to the base, of nearly the same
width throughout, narrowly oblong. Rich woods, especially W.
II. FORSYTHIA Vahl.
Shrubs. Leaves opposite or in threes, appearing later than
the flowers, serrate. Calyx very short, deciduous. Corolla yel-
low, bell-shaped, its lobes long and slender. Stamens inserted
on the base of the corolla tube. Pod 2-celled, many-seeded.
1.	F. viridissima Lindl. A hardy shrub, with branches erect or
nearly so. Leaves all simple, lance-oblong. Calyx lobes half as long as
the tube of the corolla. Lobes of the corolla spreading, narrow-oblong.
Style equal in length to the tube of the corolla. Cultivated from Asia.
2.	F. suspensa Vahl. A hardy shrub, with drooping branches.
Leaves broadly ovate, often some of them with 3 leaflets, the lateral
leaflets small. Lobes of the corolla longer, broader, and more spread-
ing than in No. 1. Style shorter than the tube of the corolla. Culti-
vated from Asia. Less common than No. 1; often trained over porches
and arbors.
III. SYRINGA L.
Tall shrubs, forking frequently, from the failure of the ter-
minal buds on most branches. Leaves simple, entire. Flowers
in close, compound panicles. Calyx 4-tootlied. Corolla salver-
shaped, the tube long, the limb 4-lobed. Pod dry, flattened at
right angles to the partition, 4-seeded.
1. S. vulgaris L. Common Lilac. A strong-growing, hardy bush.
Leaves ovate, somewhat heart-shaped. Flowers sweet-scented, in very
close, large clusters, lilac or white. Corolla lobes concave. Very com-
monly cultivated from eastern Europe.GENT]AX FAMILY
191
2. S. persica L. Persian Lilac. A more slender and less
branched shrub than No. 1. Leaves lance-ovate, somewhat nar-
rowed or tapering at the base. Flowers in rather loose clusters, not
very sweet-scented, pale lilac or white. Corolla lobes ovate, some-
what bent inward. Pods linear. Cultivated from western Asia, less
common than No. 1.
IV. CHIONANTHUS L.
Shrubs or small trees. Leaves simple, opposite, entire,
petioled, deciduous. Flowers in panicles borne on wood of
the previous season. Calyx small, 4-cleft, persistent. Corolla
wheel-shaped, 4-parted, the lobes long and linear. Stamens
2-4, included, inserted on the base of the corolla. Style short;
stigma 2-lobed. Fruit a 1-seeded drupe.*
1. C. virginica L. Fringe Tree, Old Man's Beard. A small
tree, with smooth, light gray Lark and spreading branches. Leaves
oval to oblong, acute or obtuse at each end, smooth or slightly
downy. Panicles large and loose, leafy-bracted, appearing' with the
leaves. Flowers on slender, drooping pedicels. Petals 1 in. or more
in length. Fruit ovoid, purple, 1-f in. long. Along streams, usually
on light soil.*
V. LIGUSTRUM L.
Shrubs. Leaves simple, opposite, entire, deciduous or some-
times persistent. Flowers in terminal panicles or similar,
clusters, white, small. Calyx minutely 4-toothed or truncate.
Corolla funnel form, 4-lobed. Stamens 2, short, inserted in the
tube of the corolla. Ovary free, 2-celled, 2 ovules in each cell;
style short. Fruit a 1-4-seeded, globose berry.*
1. L. vulgare L. Privet. A branching shrub, 4-10 ft. high;
branches long and slender. Leaves somewhat leathery, lanceolate to
obovate, short-petioled, tardily deciduous. Panicles dense, minutely
downy. Flowers | in. wide, fragrant. Stamens included. Berries
black. Introduced from Europe and used largely for hedges.*
80. GENTIANACEjE. Gentian Fajiily
Annual or perennial herbs. Leaves entire, usually opposite,
sometimes alternate, without stipules. Flowers actinomor-
phic, solitary or in cymes. Calyx hypogynous, 4-8-toothed
or lobed. Corolla hypogynous, wheel-, bell-, or funnel-shaped,19’2
KEY AND FLORA
4-8-lobed. Stamens 4-8, inserted on the corolla tube; fila-
ments thread-shaped; anthers facing inwards. Ovary 1-2-
celled ; ovules many, on 2 opposite placentas. Capsule 1-celled
or partially 2-celled, 2-valved, many-seeded. [The best known
genus, Gentiana, consists mainly of autumn-flowering species.]
I. OBOLARIA L.
A low, smooth, purplish-green perennial. Flowers axillary
and terminal. Calyx of 2 distinct, spatulate, bract-like sepals.
Corolla tubular-bell-shaped, 4-lobed. Stamens short, inserted
at the notches of the corolla. Style short; stigma 2-lipped.
Capsule ovoid, more or less 2-4-celled; seeds very minute
and numerous.
1. 0. virginica L. Pennywort. Stem 3-8 in. high, often several
from the same root. Leaves somewhat fleshy, wedge-obovate or
somewhat diamond-shaped, often truncate, sessile. Flowers opposite
or terminal in threes, nearly sessile. Corolla pale purple or nearly
white. Rich woodlands, among dead leaves.
II. MENYANTHES L.
Perennial, scape-bearing marsh herbs. Rootstock creeping.
Leaves of 3 leaflets. Flowers racemed. Calyx 5-parted.
Corolla fleshy, funnel-shaped, the limb 5-parted. Stamens 5,
inserted on the corolla tube. Disk of 5 liypogynous glands.
Ovary 1-celled ; style thread-shaped ; stigma 2-lobed. Capsule
globose, many-seeded.
1. M. trifoliata L. Buck Bean, Marsh Trefoil. Rootstocks
stout and matted. Leaflets obtuse, entire. Flowers f in. in diameter,
white or pinkish. Bogs, especially N.
81. APOCYNACEAi. Dogbane Family
Trees, shrubs, or herbs, with milky juice, often climbing.
Leaves usually opposite, rarely whorled, entire, nearly or
rpiite without stipules. Flowers actinomorpliic, solitary or in
cymes. Calyx 4-5-ch'ft. Corolla hypogynous, funnel-, salver-,
or bell-shaped, sometimes with scales in the throat. Stamens
4-5, borne on the corolla tube or throat; filaments very short;DOGBANE FAMILY
193
anthers somewhat attached to the stigma. Ovary of 2 carpels,
free or somewhat united ; style short; stigma entire or 2-cleft.
Fruit of 2 many-seeded pods (in the genera here described).
I.	AMSONIA Walt.
Perennial herbs. Stems erect, branched. Leaves alternate.
Flowers in terminal panicles. Calj'x small, 5-parted. Corolla
small, pale blue, funnel- or salver-form, downy within. Sta-
mens inserted above the middle of the tube, included. < Wary
of 2 carpels, united at the top by the slender style ; stigma
globose, surrounded by a cup-shaped appendage. Fruit 2 slen-
der, erect, many-seeded follicles ; seeds without tufts of hairs.*
1. A. Tabernaemontana Walt. Amsoxia. Stem smooth and gla-
brous, branched above, 2-3 ft. high. Leaves lanceolate, entire,
acuminate at the apex, acute at the base, smooth above, with a
bloom or slightly downy beneath, short-petioled. Flowers numer-
ous, on bracted pedicels. Corolla tube slender, smooth or sometimes
downy above; the lobes narrow, as long as the tube. Follicles
slender, spreading, 4-6 in. long; seeds downy. Swamps and wet
ground S.*
II.	VINCA L.
Perennial herbs or small, slender shrubs; juice not per-
ceptibly milky. Leaves evergreen. Flowers solitary, white,
blue, or purple. Calyx 5-parted; lobes taper-pointed, glandu-
lar inside at the base. Corolla salver-shaped, thickened at the
throat, 5-lobed. Stamens 5, inserted on the upper or middle
part of the corolla tube. Ovary of 2 carpels. Pods 2, slender,
cylindrical, many-seeded.
1. V. minor L. Periwinkle. Stem slender, trailing, often rooting
at the nodes, 1-3 ft. long. Leaves ovate, acute at the apex, short-
petioled, bright green.* Flowers axillary, solitary, 1 in. wide. Calyx
with linear lobes nearly as long as the inflated tube of the blue
corolla. Matured pods slender, slightly divergent. Introduced from
Europe and common in gardens.*
III.	APOCYNUM L.
Perennial herbs. Stems with very tough bark, branched
above. Leaves opposite, entire. Flowers in terminal and
axillary bracted cymes. Calyx small, 5-parted, lobes acute.194
KEY AND FLORA
Corolla bell-shaped, 5-lobed, with a small, scale-like appendage
at the base of each lobe. Stamens 5, distinct, inserted on the
base of the corolla tube. Ovaries 2, distinct, united by the
styles; stigma obtuse, 2-lobed. Pods long, slender, many-
seeded ; seeds with a tuft of hairs.*
1.	A. androsaemifolium L. Dogbane. Plant 2—3 ft. high, usually
smooth, purplish, the branches spreading and forking. Leaves 2-3
in. long, acute, mucronate ; petioles about \ in. long. Cymes mostly
terminal, few-flowered. Calyx teeth lance-ovate, about half as long
as the corolla tube. Corolla pale red or whitish, its lobes recurved.
Pods stouter than in No. 2. Roadsides and clearings ; common.
2.	A. cannabinum L. Indian Hemp. Stem erect, smooth, with
numerous erect or ascending branches. Leaves oval to oblong,
mucronate at the apex, rounded at the base, downy beneath,
short-petioled. Cymes terminal, compact, shorter than the leaves.
Flowers are on short, bracted pedicels, greenish-white, about J in.
broad. Calyx lobes lanceolate, nearly as long as the tube of the
corolla. Corolla lobes erect. Pods very slender, tapering, 3-1 in.
long. Along fences and in thickets.*
IV. NERIUM L.
Shrubs. Leaves mostly whorled in threes. Flowers in termi-
nal cymes. Calyx small, lobes acute. Corolla salverform, the
throat of the tube crowned with cleft or cut-fringed scales.
Stamens 5, short, included; anthers tipped with a hairy
bristle. Ovary of 2 carpels; style short. Pods erect; seeds
with a tuft of hairs.*
1. N. Oleander L. Oleander. Stem erect, diffusely branched
from below, 4-10 ft. high. Leaves narrowly elliptical, acute at each
end, thick and leathery, short-petioled. Flowers showy, in large
clusters, red or white, often double; scales of the crown 3- l-pointed
unequal teeth. Pods spindle-shaped, 3-4 in. long. Introduced from
Palestine. Common in cultivation.*
82. ASCLEPIADACEjE. Milk weed Family
Shrubs or herbs, often twining; juice usually milky.
Leaves generally opposite or whorled, entire, without stipules.
Flowers regular. Calyx 5-parted. Corolla 5-parted. Stamens
5: the filaments usually united around the styles, often withMILKWEED FAMILY
lflo
hood-like appendages, each with an incurved horn borne on
the stamen tube and forming a crown around the stigma
(Fig. 27, A); anthers pressing against the lobes of the stigma;
the pollen clinging together in tough, waxy or fine-grained
Fig. 27. Flower of Asclepias syriaca
A, entire flower; B, vertical section; C, diagram; D, details of pollen-masses
and glands, ca, calyx; c, corolla; hd, hood; hn, horn: a, anther; s, stig-
ma; o, ovary; g, gland; p, pollen-mass. (All considerably enlarged.)
masses. Ovary free from the calyx tube, of 2 carpels, more
or less united below but unconnected above ; styles 2 ; stigmas
5-angled; ovules several-many. Fruit consisting of 1 or 2
pods. The flowers are very highly specialized for pollination
by insects (see below, under Asclepias).196
KEY AND FLORA
I. ASCLEPIODORA Gray.
Plants much like Asclepias, hut the hoods without horns.
Lobes of the corolla ascending or spreading.
1. A. viridis Gray. Green Milkweed. Stems about 1 ft. high,
nearly smooth. Leaves alternate, short-petioled, oblong to ovate-
lanceolate. Umbels clustered. Flowers about 1 in. in diameter,
green with a purplish crown. In dry soil W. and S.
II. ASCLEPIAS L.
Perennial herbs. Flowers in simple (usually many-flowered)
umbels. Calyx small, 5-parted, its lobes reflexed. Corolla deeply
5-parted, with reflexed lobes ; crown of hoods and horns con-
spicuous (Fig. 27, A, B). Stamens with their filaments united
into a tube around the pistil and anthers attached to the stigma
(Fig. 27, D, E); anther cells 2, each cell containing an elon-
gated, pear-shaped, tough mass of pollen, a mass from one
anther always paired with one from the adjoining anther and
each two together suspended from one of the 5 split glands
on the angles of the stigma (Fig. 27, D, E). Ovaries 2 ; styles
very short. Pods 2 or sometimes 1 and the other undeveloped.
Seeds flat, each with a tuft of long, silky hairs. The flowers
are pollinated by insects, which get their feet entangled in
the clefts of the glands (Fig. 27, g) and then carry off the
pollen masses.
1.	A. tuberosa L. Butterfly IYeed, Pleurisy Root. Stems
roughish-hairy, 1-2 ft. high. Juice not milky. Leaves abundant,
linear to lanceolate-oblong. Flowers showy, usually bright orange,
in terminal cymose umbels. Horns nearly erect and slender. Pods
nearly erect, covered with fine down. In dry fields.
2.	A. decumbens L. Reclining Butterfly AVeed. Much resem-
bling A. tuberosa, but the stems reclining with the ends erect. Leaves
elliptic or oblong. Umbels racemed along the branches. In dry soil.
3.	A. purpurascens L. Purple Milkweed. Stem 1-3 ft. high,
somewhat branched above. Leaves 4-6 in. long, elliptical or nearly
so, the upper ones taper-pointed, slightly velvety beneath, short-
petioled. Umbels terminal. Flowers J in. long, dark purple; pedi-
cels shorter than the peduncle ; horn broadly scythe-shaped, with the
point bent sharply inward. Dry soil.MORNING-GLORY FAMILY
197
4.	A. syriaca L. Common Milkweed. Stem stout, 3-1 ft. high,
finely downy. Leaves -1-8 in. long, oblong or nearly so, downy be-
neath. Umbels terminal or nearly so. Flowers varying from purple
or greenish-purple to whitish, numerous, with a strong, sweet but
sickening odor; hoods with a tooth on each side of the stout horn.
Common in rich soil.
5.	A. phytolaccoides Pursli. Poke-Lf.aved Milkweed. Stem
rather slender, 3-5 ft. high. Leaves 6-9 in. long, ovate or oval-
lanceolate, taper-pointed, short-petioled. Umbels several, mostly lat-
eral; pedicels slender and drooping. Lobes of the corolla greenish;
hoods white, with 2 teeth; horns with an awl-shaped point extending
far out of the hoods. Damp thickets N. and E.
6.	A. variegata L. White Milkweed. Stem stout, leafless and
smooth below, leafy and downy in lines above. Leaves opposite, the
middle ones sometimes in fours, petioled, ovate to obovate, cuspidate,
smooth on both sides, pale beneath, edges slightly crenate. LTmbels
I-	5, compact, downy, 1-2 in. long; pedicels erect, as long as the
peduncles. Corolla white, often purple at the base; hoods roundish,
spreading, a little longer than the thick, awl-pointed, incurved horn.
Dry, open woods E. and S.*
7.	A. quadrifolia L. Four-Leaved Milkweed. Stem slender,
II—	2 ft. or more high, usually leafless below. Leaves in 1 or 2 whorls of
4 each, near the middle of the stem, and a pair or two opposite, thin,
slender-petioled, 2-4 in. long, ovate-lanceolate, taper-pointed. Umbels
usually 2, sometimes 1, with slender pedicels. Corolla lobes very pale
pink or whitish ; hoods white ; horn short, stout, and bent inward. Dry
woods and fence rows.
III. HOYA R.Br.
Shrubby, more or less climbing, smooth, tropical plants.
Leaves fleshy. Calyx 5-cleft; corolla o-lobed, wheel-shaped,
its divisions thick and with a waxy look; crown of 5 spread-
ing segments ; pollen masses fastened by the bases.
1. H. carnosa R. Br. Wax Plant. Stems long and slender, root-
ing and trailing. Leaves oval or nearly so, thick, dark green.
Flowers in close umbels, pink or whitish, the corolla lobes covered
on the upper surface with minute projections. Cultivated from
India as a house plant and in conservatories.
83. CONVOLVULACE4E. Morning-Glory Fa mil y
Usually twining herbs or shrubs, often with milky juice.
Leaves alternate (wanting in Cuscuta), without stipules.198
KEY AND FLORA
Flowers variously clustered, rarely solitary, often large and
showy. Sepals 5. Corolla hypogynous, regular, tubular, bell-
shaped or funnel-shaped; its limb more or less 5-lobed or
angled. Stamens 5, inserted on the corolla tube. Ovary usu-
ally 2-4-celled; style slender, 2-4-cleft; ovules 1 or 2 in each
cell. Capsule 1-4-celled, 2-4-valved, or bursting open across
the base.
I. IMPOMCEA L.
Annuals or perennials ; stems often twining. Flowers showy.
Calyx not bracted at the base, of 5 sepals. Corolla bell-shaped
or funnel-shaped, twisted in the bud. Stamens not projecting
from the corolla. Style slender; stigma knobbed, 2-lobed.
Fruit a 2-3-celled capsule. [/. purpurea, the common morn-
ing-glory, blossoms too late for school study. I. Batatas, the
sweet potato, seldom flowers.]
B. FI. species 1 (Quamlocit).
1.	I. Quamlocit I.. Cypress Vine. Stem slender, smooth, twin-
ing high. Leaves dark green, pinnately cut, the divisions linear,
smooth. Peduncles slender, as long as the leaves, 1-5-flowered;
pedicels thickened upward. Sepals ovate or oblong, mucronate.
Corolla bright scarlet, or sometimes yellowish-white, salverform;
the tube 1-11 in. long; the limb flat and spreading, $—| in. wide.
Capsule ovoid, twice the length of the sepals. Common in gardens.*
2.	I. hederacea Jacq. Wild Morning-Glory. Stems hairy, twin-
ing. Leaves heart-shaped, 3-lobed. Peduncles 1-3-flowered. Calyx
very hairy below. Corolla showy, bluish-purple or white. Pod usu-
ally 3-celled, with 2 seeds in each cell. A weed in fields and about
dwellings. Introduced from tropical America.
3.	I. pandurata G. F. W. Mey. Wild Potato Vine. Perennial,
from a very large, tuberous root; stem trailing or twining, smooth
or slightly downy, 5-10 ft. long. Leaves broadly heart-shaped, with
the apex slender and obtuse, sometimes fiddle-shaped or 3-lobed;
petioles slender. Peduncles longer than the petioles, 1-5-flowered.
Sepals oblong, obtuse, smooth, mucronate, the 2 outer ones shorter.
Corolla white with a purple throat, 2-3 in. wide, lobes pointed. Cap-
sule globose, 2-3-seeded, the seeds woolly on the angles. On dry or
damp sandy soil, along fences, railroad embankments, etc.; common
S. and W-*
4.	I. leptophylla Torrey. Bush Morning-Glory. Perennial.
Stems smooth, much branched, erect, ascending or reclining, 2-1 ft.PHLOX FAMILY
199
long, from a huge root. Leaves 2-5 in. long, short-petioled, linear,
acute. Peduncles short, 1-4-flowered. Sepals broadly ovate, obtuse.
Corolla pink or purple, funnel-shaped, about 3 in. long. Pod ovoid,
2-eelled. Plains W. and S.W.
II. CONVOLVULUS L.
Herbs or shrubs, with stems twining or nearly erect. Calyx
not bracted, or inclosed in 2 large, leaf-like bracts. Corolla
broadly funnelform or bell-shaped. Stamens not projecting
from the corolla. Style 1; stigmas 2; ovary and pod 1-2-
celled, 4-seeded.
1.	C. spithamseus L. Downy, stem 6-12 in. high, erect or reclin-
ing. Leaves oblong, sometimes heart-shaped or eared at the base.
Flowers white. Calyx inclosed by 2 large, oval, acutish bracts. Stig-
mas stout. In sandy soil.
2.	C. repens L. Trailing Bindweed. Stems downy, 1-3 ft.
long, trailing or twining. Leaves sometimes heart-shaped, often nar-
rowly arrow-shaped, with the lobes at the base obtuse or rounded.
Peduncles 1-flowered. Corolla white, or sometimes pink. Stigma
ellipsoidal. Bracts beneath the calyx 2, ovate. In fields.
3.	C. sepium L. Cheepers, Rutland Beauty. Stem twining or
sometimes extensively trailing. Leaves heart-arrow-shaped or some-
what halberd-shaped, the lobes at the base truncate. Flowers numer-
ous and showy, white or tinged with rose color. Bracts at the base
of the flower large, ovate, hearbshaped. Thickets and banks of
streams, often cultivated.
4.	C. arvensis L. Bindweed. A perennial, prostrate or climbing
herb, with many stems, from a long, slender rootstock. Leaves very
variable, more or less arrow-shaped, 1-3 in. long. Peduncles mostly
1-flowered; flowers white or pinkish, about f in. long. Calyx not
bracted. Stigmas linear. A weed in fields E.; adventive from
Europe.
84. P0LEM0NIACE2E. Phlox Family
Annual or perennial herbs, rarely shrubs. Leaves alternate
or the lower opposite, without stipules. Flowers in terminal,
forking cymes. Calyx hypogynous, 5-lobed. Corolla regular
or nearly so, 5-parted. Stamens 5, inserted on the corolla tube,
usually unequal. Ovary 3-celled ; style simple; stigmas 3,
linear ; capsule 3-celled, the cells 1-many-seeded.200
KEY AND FLORA
I. PHLOX L.
Perennial or rarely annual herbs ; stems erect or diffuse.
Leaves opposite, or the upper alternate, entire, without
stipules. Flowers showy, white or purple, in terminal cymes
or panicles. Calyx cylindrical or funnelform, 5-cleft, the
lobes acute. Corolla salver-form, the tube long and slender,
the limb 5-parted, the lobes spreading, entire or obcordate.
Stamens included, unequal. Ovary 3-celled, style slender.
Capsule ovoid, 3-celled, 1-few-seeded ; seeds wingless or nar-
row-winged.*
1.	P. paniculata L. Garden Phlox. Perennial; stems in clumps,
stout, erect, simple or branched above, 2-4 ft. high. Leaves ovate-
lanceolate to oblong, taper-pointed at the apex, rounded or cordate at
the base, thin, smooth; veins prominent beneath. Cymes numerous
and compact, forming a pyramidal panicle; pedicels short. Calyx
teeth long, bristle-pointed. Corolla purple to white; lobes round-
obovate, shorter than the tube. Capsule longer than the calyx tube.
In rich woods; often cultivated.*
2.	P. maculata L. Wild Sweet William. Stem erect, smooth
or nearly so, rather slender, purple-spotted, 1-2 ft. high. Lower
leaves lanceolate, the upper ones broader, taper-pointed, roundish
or heart-shaped at the base. Panicle many-flowered, narrow, ellip-
soidal. Calyx teeth lanceolate, hardly acute. Flowers purple, occa-
sionally white. Damp woods and fields.
3.	P. glaberrima L. Smooth Phlox. Stems smooth, slender,
erect, 1-3 ft. high. Leaves narrowly lanceolate or linear, 11-4 in.
long, smooth except the rough and sometimes recurved margins.
Cymes few-flowered, grouped in loose corymbs. Calyx teeth very
narrow and sharp-pointed. Corolla pink or whitish, lobes longer than
the tube. Prairies and open woods.
4.	P. pilosa L. Downy Phlox. Perennial; stem erect, slender,
simple or branched, 1-2 ft. high. Leaves linear-lanceolate to linear,
distant,spreading, long, taper-pointed, sessile; stem and leaves downy.
Cymes corymbose, loose. Flowers short-pediceled. Calyx glandular-
viscid, the teeth shorter than the tube of the purple corolla, bristle-
pointed. Corolla tube downy, lobes obovatl, Capsule twice the
length of the calyx tube. In dry, open woods.*
5.	P. divaricata L. Wild Blue Piilox. Perennial; stems erect
or ascending from a decumbent base, sticky-downy, 1 ft. high.
Leaves distant, lanceolate to oblong, acute at the apex, rounded at
the base, sessile, downy. Cymes coryinbed, loosely flowered. Calyx
teeth awl-shaped, longer than the tube. Corolla bluish-purple, A-fWATERLEAF FAMILY
201
ill. long; lobes notched at the apex, as long as the tube. Capsule
oval, shorter than the calyx teeth. In moist, open woods.*
6.	P. Drummondii Hook. Drummond’s Phlox. Annual; stem
erect or ascending, slender, weak, branching, glandular-downy, 0—1 ^
in. high. Leaves mostly alternate, lanceolate to oblong, downy, the
upper clasping by a heart-shaped base. Corymbs loose. Flowers
rather long-pediceled. Calyx tube short, the teeth lanceolate, bristle-
pointed, soon recurved. Corolla purple to crimson or white; orifice
of the tube usually with a white or yellowish star-like ring; lobes
rounded at the apex. Ovary 3-seeded; angles of the seeds winged.
Introduced from Texas and common everywhere in gardens.*
7.	P. subulata L. Ground Pink, Moss Pink, Flowering Moss.
Stems perennial, prostrate, 8-18 in. long, with many short, somewhat
upright branches, 2-4 in. high. Leaves linear-awl-sliaped, stiff, about
1 in. long, crowded, with clusters of smaller ones in their axils. Flower
clusters 3-6-flowered. Corolla pink-purple, with a darker center, or some-
times white. Forms dense mats on rocky or sandy hillsides. S. and W.
and often cultivated.
II. POLEMONIUM L.
Perennial herbs. Leaves alternate, pinnate. Flowers in
corymbs. Calyx bell-shaped, 5-lobed. Corolla wheel-shaped,
the limb with 5 obovate lobes. Stamens borne on the throat
of the corolla, the filaments enlarged and hairy below. Cap-
sule ovoid, 3-celled, many-seeded.
1. P. reptans L. Jacob’s Ladder, Blue Valerian, Bluebell.
Stems smooth, branched, and leaning over, 6-12 in. high. Leaflets
usually 7 or 9, about an inch long. Corolla blue, about o times as
long as the calyx. Capsule 3-seeded, borne on a short stalk in the
persistent calyx. Damp, open woods, sometimes cultivated.
85. HYDROPHYLLACEJE. W ATERLEAF FAMILY
Herbs, usually hairy. Leaves commonly'- alternate and alter-
nate-lobed. Flowers with their parts in fives, in appearance
not unlike those of the following family, in one-sided cymes,
which are coiled up at first. Calyx free from the ovary, usually
with appendages at the notches. Corolla often with scales or
nectar-bearing folds inside. Stamens borne by the corolla tube.
Style 2-cleft, or styles 2. Ovary’ entire and usually 1-celled.
Fruit a capsule, 2-valved, 4-many-seeded.202
KEY AND FLORA
I. HYDROPHYLLUM L.
Coarse perennials. Leaves large, petioled. Flowers white
or pale blue, inconspicuous. Calyx 5-parted, sometimes ap-
pendaged at the notches. Corolla bell-shaped, 5-cleft, with
5 double, nectar-bearing folds inside. Stamens projecting,
the filaments bearded. Style projecting; ovary covered with
bristly hairs, the placentae very broad and fleshy, inclosing
the ovules. Capsule globular, 1-4-seeded.
1.	H. macrophyllum Nutt. A coarse, rough-hairy plant, about 1 ft.
high, from scaly-toothed rootstocks. Leaves oblong, pinnate and pin-
nately cut, the divisions mucronate, obtuse, coarsely toothed. Flower
cluster dense, globular, long-peduncled. Flowers about 1 in. long.
Calyx little or not at all appendaged, its lobes broad at the base,
but with slender, tapering points. Corolla white. Rich, rocky woods
W. and S.
2.	H. virginianum L. Nearly smooth, 1-2 ft. high, stem often fork-
ing at the base. Leaves of the stem mostly near the top, pinnately
cut into 5-7 division s; lobes oval-lanceolate, deeply serrate, the
lowest ones distinct; petioles of the basal and lower leaves 4-8 in.
long. Flower clusters on peduncles longer than the petioles of the
upper leaves, from the axils of which or opposite which they arise.
Flowers about | in. long. Calyx not appendaged, its lobes narrowly
linear, bristly-margined. Corolla whitish, with purplish veins. Moist
woods.
3.	H. appendiculatum Michx. Hairy, 1-1 ft. high. Stem leaves pal-
mately 5-lobed, the lobes acute, toothed, lowest ones pinnately divided.
Flower cluster rather loose. Calyx appendaged at the notches. Corolla
blue. Stamens projecting from the corolla little or not at all. Moist
woods.
II. ELLISIA L. (MACROCALYX)
Delicate, branching annuals. Leaves pinnately lobed or
divided. Flowers small, whitish. Calyx without appendages,
5-parted, enlarged and leafy in fruit. Corolla bell-shaped or
cylindrical, little if any longer than the calyx, 5-lobed, with
5 minute appendages within the tube. Placentae, fruit, and
seeds nearly as in Ili/dm/i/ii/I/um.
1. E. Nyctelea L. Plant somewhat roughish-hairy, 6-12 in. high.
Leaves pinnately parted or divided. Peduncles 1-flowered, opposite
the leaves. Corolla whitish. Pod globose, finally pendulous. In damp,
shady places.BORAGE FAMILY
203
III. PHACELIA Juss.
Herbs, mostly annual. Leaves alternate, sometimes simple,
but in most species lobed or divided. Flowers in one-sided
clusters, often showy. Calyx 5-parted, without appendages.
Corolla with 5 spreading lobes. Ovary 1-celled, with narrow
placenta;.
1.	P. bipinnatifida Miehx. A hairy biennial. Stem upright, 1-2 ft.
high. Leaves on long- petioles, pinnately divided or deeply out into
3-7 toothed or eat segments. Racemes long, loose, many-flowered.
Flowers blue or violet, the spreading or recurved pedicels about as
long as the calyx. Calyx segments linear. Corolla broadly bell-
shaped, its appendages in pairs between the stamens. Rich soil in
thickets and along streams.
2.	P. tanacetifolia Benth. A tall, hairy annual. Leaves pinnately
cut. Spikes long, densely flowered. Flowers showy, blue. Stamens
projecting. Capsule 4-seeded. Cultivated from California.
3.	P. Whitlavia Gray. Whitlavia. A rather coarse, sticky annual.
Leaves broad, ovate, coarsely toothed, petioled. Flower clusters a
loose raceme. Flowers showy, about 1 in. long, blue or sometimes
white. Corolla bell-shaped. Stamens and style projecting. Capsule
many-seeded. Cultivated from California.
4.	P. linearis Holz. Eutoca. A much-branched, somewhat rough
or rough-hairy plant, 3-12 in. high. Leaves linear or lanceolate, en-
tire or nearly so. Flow-ers showy, violet or white, loosely panicled.
Capsule many-seeded. Cultivated from California.
86. BORAGINACE7E. Borage Family
Mostly herbs, with stems and foliage roughened with stiff
hairs. Leaves alternate and entire, not aromatic. Flowers gen-
erally in. a coiled inflorescence. Calyx 5-parted. Corolla hypogy-
nous, generally 5-lobed and regular. Stamens 5, inserted on the
corolla tube. Style 1 ; ovary commonly 4-lobed, ripening into
4 1-seeded nutlets.
I. HELIOTROPIUM L.
Herbs or low shrubs. Leaves petioled. Flowers white,
blue, or lilac, in one-sided, curved spikes. Calyx 5-parted.
Corolla salver-shaped, the throat open. Anthers almost ses-
sile. Style short; stigma conical or knobbed. Fruit sepa-
rating into 2 or 4 nutlets.204
KEY AND FLORA
1. H. peruvianum L. Common Heliotrope. Somewhat shrubby,
much branched. Leaves lance-ovate or somewhat oblong, veined
and much wrinkled, short-petioled. Flowers numerous, in a cluster
of terminal spikes, bluish-purple or lavender, very sweet-scented, the
odor not unlike that of vanilla. Cultivated from Peru.
II. CYNOGLOSSUM L.
Coarse, rough-hairy or silky biennials. Flowers small,
bluish-purple or white, in forked and usually bractless cymes.
Calyx 5-parted. Corolla funnel-shaped, the mouth closed by
prominent scales, its lobes obtuse. Stamens not projecting.
Styles stiff, persistent. Nutlets 4, covered with hooked or
barbed bristles, attached to a thickened, conical receptacle.
1.	C. officinale L. Hound's-Tongue, Sheep Lice, Dog Bur, Stick-
Tigiits. Stem 1-2 ft. high, soft-downy, panicled above. Basal
leaves 8-10 in. long, long-petioled, oblong or oblong-lanceolate ;
stem leaves sessile, linear-oblong' or lanceolate, rounded or heart-
shaped at the base. Corolla 4 in. in diameter, reddish-purple. Nut-
lets j- in. long, with a thickened border. Whole plant witli a strong
smell like that of mice. A troublesome weed; along roadsides and
in pastures; naturalized from Europe.
2.	C. virginianum L. Wild Comfrey. Perennial. Stem stout,
simple, erect, leafless above, 2-3 ft. high. Leaves oval or oblong, the
upper clasping by a heart-shaped base. Racemes bractless; flowers
pale blue, on short pedicels, which are recurved in fruit. Nutlets not
margined, separating and falling away at maturity. On dry soil.
III. LAPPULA Moeneh.
Annual or biennial herbs, grayish, witli rough hairs. Flowers
small, blue or whitish, racemed or spiked. Corolla salver-
shaped, its throat closed with 5 concave scales. Nutlets more
or less covered with prickles, which are barbed at the tip,
attached by their sides to the base of the style.
1. L. virginiana Greene. Beggar’s Lice. A coarse, biennial, 2-4
ft. high, the stem much branched above. Basal leaves roundish-
ovate or heart-shaped, on slender petioles; stem leaves 3-4 in. long,
pointed at both ends. Racemes 1-3 in. long, terminating the slender,
spreading branches; flowers small, bluish-white. Fruit forming a
troublesome bur. Fence rows and thickets.BORAGE FAMILY
205
IV. MYOSOTIS L.
Low, annual, biennial, or perennial herbs ; stems branching,
erect, or diffuse. Leaves alternate, entire. Flowers small,
blue, pink, or white, in elongated, bractless racemes. Calyx
5-cleft, the lobes erect or spreading in fruit. Corolla salver-
form, 5-lobed, the tube as long as the calyx, the throat with
5 small appendages. Stamens 5, inserted in the tube of the
corolla, included. Ovary 4-parted; style slender. Nutlets
smooth or downy, elliptical, compressed.*'
1.	M. scorpioides L. Forget-Me-Not. Perennial, from slender
rootstocks; sterns slender, downy, rooting at the nodes, 6-15 in.
long. Leaves oblong to oblong-lanceolate, obtuse, nan’owed to the
sessile base, appressed-downy. Racemes nrany-flowered; pedicels
becoming elongated in fruit. Lobes of the calyx shorter than the
tube, spreading in fruit. Corolla blue, with a yellow eye. Nutlets
angled, smooth. In gardens and often naturalized from Europe.*
2.	M. laxa Lehm. Small Forget-Me-Not. Annual or perennial;
whole plant downy; stem slender, weak, decumbent and rooting at
the base, 1-2 ft. long. Lower leaves spatulate, the upper lanceolate.
Racemes loosely flowered, becoming elongated in fruit; pedicels
spreading. Calyx rough-hairy, the lobes as long as the tube. Corolla
pale blue, with a yellow eye, Nutlets convex on all sides. On low
ground and in brooks and ponds.*
V. MERTENSIA Roth.
Perennial herbs. Leaves generally pale, smooth, and entire.
Calyx short, deeply 5-cleft or 5-parted. Corolla somewhat
trumpet-shaped or funnel-shaped, often with 5 small folds or
ridges in the throat, between the points of insertion of the
stamens. Style long and slender. Nutlets smooth, or at length
becoming wrinkled.
1. M. virginica Link. Lungwort, Bluebells. Smooth, nearly
erect, 1-1J- ft. high. Basal leaves large, obovate or nearly so, and
petioled; stern leaves smaller, sessile. Flowers clustered. Corolla
nearly trumpet-shaped, varying with age from lilac to blue (or occa-
sionally white). Stamens with slender filaments projecting beyond
the corolla tube. Damp, open woods, and banks of streams; some-
times cultivated.206
KEY AND FLORA
VI. LITHOSPERMUM L.
Herbs, with stout, usually reddish roots. Flowers appearing
axillary and solitary or else in leafy-bracted spikes. Corolla
funnel-shaped or salver-shaped, with or without folds or
appendages at the mouth of the tube ; the limb 5-cleft, its
divisions rounded. Stamens included in the corolla tube, the
anthers nearly sessile. Nutlets either smooth or wrinkled,
generally very hard and bony.
1.	L. arvense L. Corn Gromwell. A rough weed, about 1 ft.
high. Leaves narrowly lanceolate. Flow-ers inconspicuous, whitish,
in the upper leaf axils. Corolla hardly extending beyond the calyx,
without appendages in the throat. Nutlets rough or wrinkled and
dull. Sandy banks and roadsides ; naturalized from Europe.
2.	L. Gmelini Hitchc. Hairy Puccoon. Rough-hairy, perennial,
1-2 ft. high. Corolla deep orange-yellow, with appendages in the
throat and clad with wool within at the bottom; flowers handsome,
peduncled, in a crowded cluster. Dry, open pine woods, in sandy soil.
3.	L. canescens Lehm. Puccoon, Indian Paint. Perennial;
clothed with soft hairs, 8-12 in. high. Flowers axillary and sessile.
Corolla appendaged, not woolly within, showy, orange-yellow. Banks
and open woods.
4.	L. angustifolium Michx. Narrow-Lkaved Puccoon. Peren-
nial; rough, 0-18 in. high, from a deep root. Leaves linear, sessile,
acute or nearly so. Flowers pediceled in terminal leafy racemes of
two kinds, the earlier showy, bright yellow’, with a corolla tube an
inch or more long ; the latter much smaller, pale yellow, cleistoga-
mous, fruiting abundantly. Pedicels of the cleistogamous flowers at
length recurved. Nutlets ovoid, white, very smooth, slightly pitted.
In dry soil \V.
VII. ONOSMODIUM Michx.
Mostly rough-hairy perennial herbs. Leaves sessile, entire,
with prominent veins. Flowers rather small, white, greenish
or yellowish, in leafy one-sided spikes or racemes. Calyx 5-
parted into linear divisions. Corolla tubular or tubular-funnel-
form, with 5 acute erect lobes. Stamens 5, perigynous, not
projecting from the corolla tube. Style thread-like, decidedly
projecting. Nutlets usually only 1 or 2, white, smooth and
shining.
1. 0. virginianum A.DC. Steins rather slender, 1-3 ft. high, cov-
ered with rough, stiff bristles. Leaves oblong or oblong-lanceolate,VERBENA FAMILY
207
the lower ones narrowed at the base. Corolla narrow, its lobes lance-
awl-shaped, slightly bearded outside with long bristles. In dry
thickets or on hillsides.
2. 0. hispidissimum Mackenzie. Stem stout, upright, 1-4 ft. high,
shaggy with long bristly hairs. Leaves from lanceolate to oblong,
acute, 2-11- in. long. Corolla rather broad, its lobes ovate-triangular
or triangular-lanceolate, thickly hairy outside. Nutlets with a very
short neck at the base. Rich soil along river banks and bottom lands.
Vm. ECHIUM L.
Herbs or sometimes shrubs, usually stout, coarse, and hairy.
Leaves entire. Flowers white, reddish-purple or blue, in spiked
or panicled racemes. Calyx 5-parted. Corolla tube cylindrical
or funnel-shaped; the throat dilated; the limb with 5 unequal
lobes. Filaments unequal, attached to the corolla below, pro-
jecting from the corolla. Style thread-like; stigma 2-lobed.
Nutlets 4, ovoid or top-shaped, wrinkled.
1. E. vulgare L. Blue Thistle, Blue M’f.ed. Blue Devils.
Stems 1-3 ft. high, more or less erect, leafy, covered with stinging
hairs. Root leaves lanceolate or oblong, petioled, 4-8 in. long;
stem leaves sessile, acute, rounded at the base. Flowers showy,
reddish-purple in the bud, changing to bright blue. A very trouble-
some weed, especially iu fallow fields. Naturalized from Europe.
87. VERBENACE7E. Veebexa Family
Herbs, shrubs, or trees. Leaves opposite or whorled, with-
out stipules. Flowers zygomorphic, in bracted cymes. Calyx
hypogynous, cleft or toothed. Corolla hypogynous, tubular,
usually more or less 2-lipped. Stamens usually 4 (2 long and
2 short), inserted on the corolla tube. Ovary usually 2—4-celled
(in Phryma 1-celled), with the style springing from its summit.
I. VERBENA L.
Annual or perennial herbs. Leaves simple, opposite, ser-
rate or pinnately lobed. Flowers in terminal spikes which
become much elongated in fruit. Calyx tubular, 5-ribbed, 5-
toothed. Corolla salverform or funnelform, the tube often
curved, bearded in the throat, limb spreading, 5-lobed, often208
KEY AND FLORA
somewhat 2-lipped. Stamens 4 (2 long and 2 short), rarely
only 2, included. Ovary 2-4-celled, 2-4-ovuled; style slen-
der, 2-lobed. Fruit 2-4 smooth or roughened, 1-seeded nut-
lets. [Several of the commonest species are tall, coarse herbs,
which blossom too late for school study.]*
1.	V. officinalis L. European Vervain. Annual; stem erect,
slender, nearly or quite smooth, branching, 1-3 ft. high. Leaves
ovate to obovate in outline, pinnately lobed or divided, narrowed and
entire toward the base, downy beneath; petioles margined. Spikes
several, very slender; flowers small, purple; bracts shorter than the
calyx. In fields and waste places. Naturalized from Europe.*
2.	V. angustifolia Miclix. Narrow-Leaved Vervain. Peren-
nial, rough-hairy; stem simple, or branched below, from a creeping
base, 1-2 ft. high. Leaves lanceolate to spatulate, obtuse and toothed
at the apex, tapering to a sessile base. Spike peduncled, slender,
close-flowered; bracts about the length of the calyx. Corolla purple,
tube slightly curved, J in. long. In dry, open woods.*
3.	V. bracteosa Michx. Perennial; widely spreading or decumbent,
hairy; stems 6-15 in. long, 4-sided, branching from the base. Leaves
wedge-lanceolate, 3-cleft or pinnately cut, short-petioled. Sjoikes ses-
sile, stout, with large bracts, the lower ones pinnately cut and longer
than the flowers. Flowers small, purple. On prairies and waste ground.
4.	V. bipinnatifida Nutt. Perennial; plant rough-hairy, producing
suckers, erect, 6-18 in. high. Leaves with petioles, or the upper ones
sessile, once or twice pinnately parted into oblong or linear divisions.
Spikes stout, dense and solitary at the ends of the branches; bracts
usually longer than the calyx. Corolla bluish-purple or lilac, less
than l in. in diameter. Dry plains and prairies W. and S.
5.	V. canadensis Britton. Wild Verbena. A slender-stemmed,
somewhat reclining annual, 1 ft. or less in height. Leaves ovate or
nearly so, wedge-shaped at the base, lobed and toothed or 3-cleft.
Flowers showy, reddish-purple or lilac (seldom white), in a peduncled
spike. Calyx teeth as long as or longer than the bracts. Corolla very
slightly bearded in the throat. In dry prairie soil and open woods;
also cultivated. [Other somewhat similar cultivated species are from
Brazil.]
II. CALLICARPA L.
Shrubs. Leaves simple, petioled, opposite or whorled, glan-
dular-dotted. Flowers in axillary cymes. Calyx 4-toothed or
entire. Corolla funnelform, 4-cleft, actinomorphic. Stamens
4, equal, projecting. Ovary 4-ovuled; style slender; stigma
knobbed. Fruit a 1-4-seeded berry.*MINT FAMILY
209
1. C. americana L. French Mulberry, Mexican Mulberry.
Shrubs, with star-shaped glandular or scurfy down, widely branched,
3-8 ft. high. Leaves ovate to oblong, acute at each end, crenate-
serrate, rough above, downy beneath, glandular-dotted ; petioles slen-
der. Cymes many-flowered, the peduncle as long as the petiole;
pedicels short. Calyx cup-shaped, the teeth short. Corolla double
the length of the calyx, blue. Fruit violet-purple, very conspicuous
in autumn. Common in fields and thickets S.*
88. LABIATiE. Mint Family
Mostly herbs, with square stems and opposite, mere or less
aromatic, leaves, without stipules. Flowers generally in cyme-
like axillary clusters, which are often grouped into terminal
spikes or racemes. Calyx tubular, usually 2-lipped, persistent.
Corolla usually 2-lipped. Stamens 4 (2 long and 2 short) or
only 2. Ovary free, with 4 deep lobes, which surround the
base of the style. Fruit consisting of 4 nutlets, ripening
inside the base of the calyx.
Stamens 4.	^
(a) Calyx 2-lipped.
Lips entire.	Scutellaria,	I
Lips toothed and cleft. Plants not aromatic. Prunella, IV
Lips toothed and cleft. Plants aromatic. Leaves extremely
small.	Thymus, IX
(?)) Calyx not 2-lipped, or not much so.
Calyx tubular, 5-10-toothed. Stamens not projecting from
tube of corolla.	Marrubium, II
Calyx tubular, with 5 equal teeth. Stamens under upper
lip of corolla.	Nepeta,	III
Ctlyx tubular, bell-shaped, with 5 awl-shaped teeth. Stamens
not turned down after maturing.	Lamium,	V
Calyx top-shaped, with spreading spiny teeth. Leonurus, VI
Calyx as in V. Stamens turned down after maturing.
Staehys, VII
Stamens 2.
B
Salvia, VIII210
KEY AND FLORA
I.	SCUTELLARIA L.
Mostly slender herbs, not aromatic. Flowers solitary or in
pairs, axillary or in terminal spikes or racemes. Calyx bell-
shaped, 2-lipped, the upper part swollen into a helmet-shaped
pouch; mouth of the calyx closed after flowering. Corolla
tube long, naked inside. Stamens 4, the anthers meeting in
pairs, hairy-fringed. Style with a very short upper lobe.
[The species here described are not the commonest ones, but
most of the others grow in damp soil and bloom later.]
1.	S. serrata Andr. Skullcap. Stem not much branched, 1-3 ft.
high. Stem leaves serrate, taper-pointed at both ends, ovate or nearly
so. Racemes single, loose. Calyx rather hairy. Corolla 1 in. long,
the lips of equal length. Woods.
2.	S. pilosa Michx. Hairy Skullcap. Stem more or less hairy,
not much if at all branched, 1-3 ft. high. Leaves a few distant pairs,
diamond-ovate, oblong-ovate, or roundish-ovate, scalloped, obtuse,
the lower heart-shaped or nearly truncate at the base, with long
petioles. Racemes short, few-flowered. Corolla in. long; tube
whitish, lips blue, the lower one rather shorter. Open woodlands
and dry soil.
3.	S. integrifolia L. Large-Flowered Skullcap. Stem covered
with fine, grayish down, usually unbranched, 1-2 ft. high. Leaves
lance-oblong or nearly linear, mostly entire, obtuse, with very short
petioles. Corolla 1 in. long, tube pale, lips large and spreading, blue.
Dry ground.
4.	S. parvula Michx. Small Skullcap. Perennial with necklace-
like tuber-hearing rootstocks. Stems slender, minutely downy, 3-12
in. long, erect or spreading. Leaves varying from ovate to lanceo-
late, or the lower nearly round. Flowers solitary in the axils of the
upper leaves. Corolla in. long, violet, downy. In moist, sandy soil.
II.	MARRUBIUM L.
Perennial, downy, or woolly herbs. Whorls of flowers axil-
lary; flowers small; bracts leaf-like. Calyx tubular, 5-10-
toothed ; teeth somewhat spiny. Corolla short; upper lip erect,
lower spreading, 3-cleft, the middle lobe broadest. Stamens 4,
not projecting. Lobes of the stigma short and blunt.
1. M. vulgare L. IIorehound. Steins somewhat reclining, stout,
branching, leafy, 1-1 | ft. high. Leaves broadly ovate, heart-shaped
or wedge-shaped at the base, scalloped, leathery and wrinkled. WhorlsMINT FAMILY
211
of flowers dense. Calyx teeth hooked at the tip. Corolla 1 in. long,
white. Cultivated from Europe as an herb (used in preparation of
horehound candy) and somewhat naturalized.
III.	NEPETA L.
Erect or prostrate herbs. Whorls of flowers axillary or ter-
minal ; flowers blue or white. Calyx tubular, 15-ribbed, 5-
toothed. Corolla tube slender below, dilated at the throat,
naked; upper lip notched or 2-cleft; lower lip 3-cleft, middle
lobe large. Stamens 4, ascending under the upper lip, the
upper pair longer. Lobes of the stigma awl-shaped.
B. FI. species 2 (Glecoma).
1.	N. Cataria L. Catnip. Stem grayish, downy, 2-4 ft. high,
branched, very leafy. Leaves large, ovate-heart-shaped, deeply scal-
loped, serrate, white and downy beneath. Corolla about .1 in. long,
whitish with purple dots. Naturalized from Europe; a common weed
about dooryards.
2.	N. hederacea Trevisan. Ground Ivy, Gill-over-the-Ground,
Creeping Charley, Crow Victuals, Robin Runaway. Creep-
ing. Leaves roundish, kidney-shaped, and crenate. Corolla bluish-
purple, three times as long as the calyx. Common in damp places
about houses and gardens. Naturalized from Europe.
IV.	PRUNELLA L.
Perennials, with stems simple or nearly so, and sessile, 3-
flowered flower clusters in the axils of kidney-shaped bracts,
the whole forming a spike or head. Calyx tubular-bell-shaped,
somewhat 10-ribbed; upper lip broad, 3-toothed, the teeth short;
lower lip with 2 longer teeth. Upper lip of the corolla upright,
arched, and entire; the lower spreading, reflexed, fringed, and
3-cleft. Stamens 4, reaching up under the upper lip, with the
tips of the filaments 2-tootlied; only one tooth anther-bearing.
1. P. vulgaris L. Self-Heal, Healall, Carpenter Weed.
Leaves with petioles, ovate-oblong, either entire or toothed, often
somewhat hairy. Corolla usually blue or bluish, somewhat longer
than the brown-purple calyx. Open woods and fields everywhere.
V.	LAMIUM L.
Annual or perennial hairy herbs. Calyx tubular-bell-shaped,
5-veined, with 5 awl-pointed teeth of nearly equal length.212
KEY AND FLORA
Corolla with, dilated throat, upper lip arched, middle lobe of
the lower lip notched, the lateral lobes small, close to the
throat of the corolla. Stamens 4, rising beneath the upper lip.
1.	L. amplexicaule L. LIenbit, Dead Nettle. An annual or
biennial weed. Leaves roundish, deeply scalloped, the lower ones
petioled, the upper sessile and clasping. Corolla sometimes f in.
long, downy, rose-colored or purplish. Not uncommon about gardens
and dooryards. Naturalized from Europe.
2.	L. purpureum L. Stem 6-18 in. high, silky-hairy or nearly
smooth, reclining below, branched from the base. Leaves long-peti-
oled, obtuse, heart-shaped, scalloped. Whorls of flowers mostly
terminal, crowded. Corolla J—§ in. long, purple (rarely white). Nat-
uralized from Europe.
VI. LEONURUS L.
Erect herbs. Leaves lobed. Whorls of flowers axillary,
densely flowered, scattered; bractlets awl-shaped; flowers
small, pink or white. Calyx 5-nerved, top-shaped, with 5
rather spiny, spreading teeth. Corolla with' upper lip erect
and entire, lower 3-cleft. Stamens 4 ; anthers joined in pairs.
Nutlets with 3 projecting angles, their sides channeled.
1. L. cardiaca L. Motherwort. Stem 2-4 ft. high, prominently
angled, stiff, stout, upright, very leafy. Leaves palmately lobed or
cleft; basal ones long-petioled; lower stem leaves many-cleft, the
upper ones 3-cleft, prominently nerved, the divisions acute. Corolla
J in. long, pale rose color, the upper lip and outside of the tube
densely soft-bearded. Common about dooryards and fence rows.
Naturalized from Europe.
VII. STACHYS L.
Herbs, rarely shrubs. Leaves scalloped or serrate. Whorls
of flowers 2 or more flowered, usually in terminal racemes.
Calyx nearly bell-shaped, 5-toothed. Corolla tube cylindrical,
usually with a ring of hairs inside, not dilated at the throat;
upper lip erect or spreading; lower spreading, 3-lobed, the
middle lobe largest. Stamens 4, the 2 lower longest.
1. S. palustris L. Perennial; stem erect, 4-angled, 2-3 ft. high,
haii-y, especially on the angles, with projecting or reflexed hairs,
leafy. Stem leaves short-petioled or sessile, ovate-lanceolate or ob-
long-lanceolate, scalloped-serrate, coarsely or finely downy, roundishMINT FAMILY
213
at the base, rather obtuse at the tip. Calyx bristly, the lance-awl-
shaped teeth rather spiny. Upper lip of the corolla downy. In wet
soil, especially X.
2. S. tenuifolia Willd., var. aspera. Taller than No. 1; angles of
the stem covered with stiff reflexed bristles, but the sides often
smooth. Leaves serrate, nearly all w'ith distinct petioles. Calyx
usually smooth. Corolla smooth throughout. Damp thickets and
along streams.
VIII.	SALVIA L.
Annual, biennial, or perennial herbs, or sometimes shrubby.
Flowers in spikes, racemes, or panicles, usually showy. Calyx
tubular or bell-shaped, not bearded in the throat, 2-lipped,
the upper lip entire or 3-toothed, the lower 2-cleft. Corolla
2-lipped; the upper lip entire or notched, the lower spread-
ing, 3-lobed, with the middle lobe longer. Stamens 2, short;
anthers 2-celled, the upper cell fertile, the lower imperfect.
Style 2-cleft. Nutlets smooth.*
1.	S. lyrata L. Lyre-Leaved Salvia. Biennial or perennial;
stem erect, sparingly branched above, rough-hairy, 1-2 ft. high.
Leaves mostly basal, spreading, lyrate-pinnatifid, usually purple;
stem leaves small, sessile or short-petioled. Racemes many-flowered,
whorls about 6-flowered. Calyx teeth short on the upper lip, long
and awl-shaped on the lower. Corolla blue or purple; the tube about
1 in. long, dilated upward. On dry soil.*
2.	S. officinalis L. Garden- Sage. Stem shrubby, slender, much
branched below, 1 ft. high. Leaves grayish-green, lance-oblong, cre-
nate, wrinkled. Flowers in terminal spikes, w'horls several-flowered.
Corolla blue, upper lip strongly arched, about equaling the lower.
A common garden herb. Cultivated from Europe.*
IX.	THYMUS L.
Small, much-branched shrubs, very aromatic. Leaves small,
entire, margins often rolled under. Whorls of flowers few-
flowered, in loose or close spikes ; bracts very small; flowers
usually purple. Calyx ovoid, 2-lipped; upper lip 3-toothed;
lower 2-cleft, woolly in the throat. Corolla slightly 2-lipped.
Stamens 4, usually projecting from the flower, straight; lower
pair longer.
1. T. Serpyllum L. Creeping Thyme. Smooth or hairy, stem
prostrate, the flowering branches somewhat ascending. Leaves214
KEY AND FLORA
in. long, flat, ovate or oliovate-lanceolate, obtuse. Flowers crowded
in spikes at the end of the branches. Corolla rose-purple, j-f in.
long. Naturalized from Europe.
2. T. vulgaris L. Garden Thyme. More erect than No. 1.
Leaves somewhat curled under at the edges. Flower clusters shorter
and not all terminal. Corolla pale purple. Cultivated from Europe
as an herb.
89. SOLANACE®. Nightshade Family
Mostly tropical herbs or shrubs (rarely trees). Leaves usu-
ally alternate, without stipules. Flowers actinomorphic, borne
on bractless pedicels at or above the leaf axils, or in cymes.
Calyx hypogynous, 5-cleft, usually persistent. Corolla hypogy-
nous, wheel-shaped, bell-shaped, or salver-shaped, 5-lobed. Sta-
mens 5, short, inserted on the corolla tube. Ovary 2-celled or
imperfectly 4-celled; style simple; stigma simple or lobed.
Fruit a many-seeded capsule or berry.
I. SOLANUM L.
Herbs or shrubs ; stems often prickly, sometimes climbing.
Leaves alternate, often nearly or quite opposite. Flowers clus-
tered, the peduncles often opposite or above the axils. Calyx
spreading, 5-toothed or 5-cleft, persistent. Corolla wheel-shaped,
5-lobed. Stamens 5, projecting, the filaments very short, the
anthers long and meeting about the style. Ovary 2-celled;
style slender. Fruit a many-seeded, juicy berry.*
1.	S. Dulcamara L. Bittersweet. Perennial; stems rather
shrubby, long, and climbing. Leaves heart-shaped, or some of them
with irregular lobes, or ear-like leaflets at the base. Flowers blue or
purple, somewhat cymose. Berries showy, of many shades of orange
and red in the same cluster, according to their maturity. Naturalized
from Europe.
2.	S. nigrum L. Nightshade. Annual; stem smooth, or downy
with simple hairs, erect, diffusely branched; branches wing-angled,
1-3 ft. high. Leaves ovate, irregularly toothed or entire, somewhat
inequilateral, petioled. Flowers in lateral, peduncled umbels, small,
white, drooping. Calyx lobes obtuse; corolla ■’—) in. wide; filaments
downy; berries globose, smooth, black when ripe. Common in culti-
vated fields and waste places*NIGHTSHADE FAMILY
215
3.	S. carolinense L. Horse Nettle. Perennial; stem erect,
branched, downy with star-shaped hairs, armed wTith straight yel-
low prickles, 1-3 ft. high. Leaves ovate-oblong, deeply toothed or
lobed, acute at the apex, abruptly contracted to the short petiole,
prickly on the veins. Ilacemes lateral, few-flowered; pedicels re-
curved in fruit. Calyx lobes taper-pointed. Corolla deeply angular-
lobed, blue or white; berry globose, smooth, yellow. A common
weed.*
4.	S. rostratum Dunal. Sand Bur, Buffalo Bur. Annual; the
whole plant beset with yellow prickles; stem erect, diffusely branched,
1-2 ft. high. Leaves broadly oval or ovate in outline, deeply pin-
nately lobed or parted, petioled, downy with star-shaped hairs.
Racemes few-flowered; pedicels erect in fruit. Calyx very prickly,
becoming enlarged and inclosing the fruit. Corolla bright yellow,
5-angled, about 1 in. broad. From the West, becoming a troublesome
weed in some places.*
5.	S. tuberosum L. Irish Potato. Annual; stem diffusely
branched, downy, underground branches numerous and tuber-bear-
ing. Leaves irregularly pinnatifid and divided. Flowers in cyniose
clusters, white or purple, with prominent yellow anthers; pedicels
jointed. Corolla 5-angled, j-1 in. broad. Fruit a globose, greenish-
yellow, many-seeded berry, about f in. in diameter. Cultivated from
Chile.*
n. LYCOPERSICUM Hill.
Annual; stem diffusely branched. Leaves pinnately divided.
Flowers in raceme-like clusters on peduncles opposite the
leaves. Calyx 5-many-parted, persistent. Corolla wheel-
shaped, 5-6-parted. Stamens 5-6, inserted in the short tube
of the corolla; filaments short, anthers elongated. Ovary 2-
several-celled; style and stigma simple. Fruit a many-seeded
berry.*
1. L. esculentum Mill. Tomato. Stem diffusely branched, at
length leaning over, furrowed and angled below, sticky-hairy, 3-5
ft. long. Leaves irregularly lobed and pinnatifid, petioled. Calyx
lobes linear, about as long as the yellow corolla. Fruit (in the wild
state) globose or ovoid, red or yellow, i-J in. in diameter, but greatly
enlarged in cultivation. Common in cultivation from tropical
America.*
m. LYCIUM L.
Shrubs or woody vines, often spiny. Leaves entire, alter-
nate, often fascicled. Flowers solitary or clustered, terminal216
KEY AND FLORA
or axillary. Calyx persistent, 4-5-lobed or toothed, not en-
larged in fruit. Corolla funnelform or bell-shaped, the limb 4-5-
lobed, the lobes obtuse. Stamens 4-5, projecting. Ovary 2-celled ;
style single ; stigma obtuse. Fruit a many-seeded berry.*
1. L. halimifolium Mill. Matrimony Vine. Stem slender, branch-
ing, twining or trailing, G-15 ft. long; branches angled, spiny. Leaves
elliptical, smooth, entire, sessile or short-petioled. Flowers solitary
or few in the axils; peduncles long and slender. Corolla spreading,
greenish-purple, J-J in. wide. Berry oval, orange-red. Introduced
from Africa, and often planted for covering trellises.*
IV. DATURA L.
Annual or perennial, strong-scented herbs; stems tall and
branching. Leaves petioled, entire or lobed. Flowers large, soli-
tary in the forks of the branches. Calyx tubular, 5-tootlied or
lobed, the upper part deciduous and the lower persistent. Corolla
funnelform, 5-angled. Stamens 5, inserted in the corolla tube.
Ovary 2-celled or imperfectly 4-celled; style filiform ; stigma
2-lobed. Fruit a spiny, 4-valved, many-seeded capsule.*
1.	D. Stramonium L. Jimson Weed. Annual; stem smooth, green,
stout, forking above, 1-4 ft. high. Leaves ovate to oblong-ovate,
acute at the apex, narrowed at the base, sinuate-toothed, petioled.
Calyx 5-angled. Corolla white, about 4 in. long. Capsule ovoid, erect,
*2 in. long. A common weed; poisonous. Naturalized from Asia (?).*
2.	D. Tatula L. Taller, with a purple stem; flowers rather later
than No. 1. Corolla violet-tinged. Naturalized from tropical America.
V. PETUNIA Juss.
Herbs; leaves alternate and entire. Divisions of the calyx
oblong-spatulate. Corolla showy, spreading, funnel-shaped,
not perfectly actinomorphic. Stamens 5, somewhat unequal
in length, inserted in the middle of the corolla tube and not
projecting beyond it. Capsule 2-celled, containing many very
small seeds.
1. P. violacea LindL Common Petunia. Stems rather weak and
reclining. Leaves covered with clammy down. Corolla varying from
pale pink to bright purplish-red, often variegated, with a broad,
inflated tube, which is hardly twice as long as the calyx. Cultivated
annual from South America.FIGWORT FAMILY
217
2. P. nyctaginiflora Juss. White Petunia. Leaves somewhat
petioled. Tube of corolla long and slender. Flowers white. Culti-
vated from South America. This and the preceding species much
mixed by hybridization.
90. SCR0PHULARIACE2E. Figwort Family
Mostly herbs, with flowers not actinomorphic. Calyx free
from the ovary and persistent. Corolla often 2-lipped. Sta-
mens usually 2 long and 2 short, or only 2 in all, inserted on
the corolla tube, often 1 or 3 of them imperfectly developed.
Pistil consisting of a 2-celled and usually many-ovuled ovary,
with a single style aud an entire or 2-lobed stigma.
Corolla wheel-shaped, stamens 5.	Verbascum, I
Corolla wheel-shaped or salver-shaped, nearly actinomorphic,
stamens 2.	Veronica, VI
Corolla 2-lipped, the mouth closed by a palate, tubular below, a
spur at the base.	Linaria, II
Corolla 2-lipped, the mouth closed by a palate, tubular below, a
short, broad pouch at the base.
Corolla decidedly 2-lipped.
Stamens with anthers 2.
Stamens 4, with a fifth antherless filament.
Stamens 4, the anther cells unequal.
Stamens 4, the anther cells equal.
Antirrhinum, III
Gratiola, V
Pentstemon, IAT
Castilleja, VII
Pedicularis, VIII
I. VERBASCUM L.
Biennial; stem tall, erect. Leaves alternate. Flowers in
spikes, racemes, or panicles. Calyx deeply 5-cleft. Corolla
wheel-shaped, 5-lobed, the lobes nearly equal. Stamens 5,
unequal, declined; some or all of the filaments bearded.
Style flattened at the apex. Fruit a globose capsule; seeds
roughened.*
1. V. Blattaria L. Moth Mullein. Stem erect, slender, simple
or sparingly branched, smooth below, downy above, 2-4 ft. high.
Leaves oblong to lanceolate, acute at the apex, obtuse or truncate at
the base, dentate to pinnately lobed, the lower petioled, the upper218
KEY AND FLORA
sessile and clasping. Raceme long and loose, glandular-downy; pedi-
cels bracted. Corolla white or yellow, marked with brown on the back,
about 1 in. wide. Filaments all bearded with purple hairs. Capsule
longer than the calyx. Common in fields and waste places. Natural-
ized from Europe.*
II. LIN ARIA Hill
Herbs, rarely shrubby. Lower leaves opposite, whorled or
alternate. Flowers in bracted racemes or spikes, or axillary and
solitary. Calyx 5-parted. Corolla 2-lipped, the tube spurred.
Stamens 4, with sometimes a rudiment of a fifth. Stigma notched
or 2-lobed. Capsule ovoid or globose; cells nearly equal.
1.	L. vulgaris Hill. Butter and Eggs, Jacob’s Ladder, Wild
Flax. A perennial, erect, smooth herb, with a bloom; stem 1-2 ft.
high. Leaves linear or lanceolate, 1—3 in. long, often whorled. Ra-
cemes densely flowered. Sepals shorter than the spur. Corolla yel-
low, |-1 in. long; spur parallel to and as long as the tube; throat
closed by a palate-like fold. Common in dry fields and pastures and
along roadsides. Naturalized from Europe.
2.	L. canadensis Dumont. Toadflax. Biennial; flowering stems
erect, slender, rarely branched, smooth, 1-2 ft. high; sterile stems
prostrate, with opposite or whorled leaves, 2-6 in. long. Leaves
linear, entire, sessile. Racemes erect, slender; pedicels erect, as
long as the calyx. Corolla small, blue and white, the spur thread-
like, curved, longer than the pedicels. Capsule 2-valved, the valves
3-toothed. On dry or cultivated ground E.
III. ANTIRRHINUM L.
Annual or perennial herbs. Leaves entire, rarely lobed, the
lower ones opposite, the upper alternate. Flowers axillary and
solitary, or racemed and bracted. Calyx 5-parted. Corolla 2-
lipped; the tube with a sac, the broad-bearded palate closing
the throat. Stamens 4. Stigma with 2 short lobes. Capsule
2-celled, the upper cell opening by 1 pore, the lower by 2.
1. A. majus L. Snapdragon. Perennial; stem erect, smooth
below, glandular-downy above, 1-2 ft. high. Leaves linear to
oblong-lanceolate, entire, smooth, sometimes fleshy, sessile "or short-
petioled. Flowers in a terminal raceme; pedicels short, stout, erect
in fruit. Corolla 1.1-2 in. long, of many colors. Capsule oblique, the
persistent base of the style bent forward. Common in gardens; cul-
tivated from Europe, and often escaped.*FIGWORT FAMILY
219
IV. PENTSTEMON Mitchell
Perennials, the stems branching from the base, unbranched
above. Leaves opposite. Flowers usually showy, in a ter-
minal panicle. Calyx of 5 nearly distinct sepals. Corolla
tubular, the tube wide above and narrowed below; 2-lipped.
Stamens 4 (2 long and 2 short), with a fifth antherless fila-
ment as long as the others, its upper half bearded. Capsule
ovoid, acute.
1.	P. hirsutus Willd. Stem somewhat sticky-downy, 1-2 ft. high.
Leaves varying from oblong to lanceolate, 2-4 in. long, usually with
small teeth. Flower cluster narrow. Corolla dingy violet, purplish,
or whitish; the tube not much widened above, its throat nearly closed
by a hairy palate. Sterile filament much bearded. Dry hillsides or
stony ground.
2.	P. gracilis Xutt. Slender Beardtoxgue. Stem 6-18 in.
high, smooth below but the flower cluster covered with glandular,
sticky hairs. Basal leaves spatulate or oblong; stem leaves most of
them linear-lanceolate. Corolla purple or whitish, ;]-l in. long, the
tube enlarged above and its throat entirely open. Sterile filament
bearded above along half its length. On moist prairies IV.
3.	P. laevigatus Ait. Stem usually smooth except the flower cluster,
2-4 ft. high. Leaves shining, those of the stem ovate-lanceolate or
broadly lanceolate, 2-5 in. long, with a somewhat heart-shaped, clasp-
ing base. Flower cluster broader than in Xo. 1. Corolla white or
oftener purplish, suddenly widened above, the throat not closed.
Sterile filament slightly bearded toward the top. In rich soil.
4.	P. Digitalis Xutt. Much resembling Xo. 3, but taller, sometimes
5 ft. high. Corolla white, the tube abruptly widened. In fields and
thickets; sometimes cultivated.
5.	P. barbatus Roth. Stems slender and rod-like, 3-4 ft. high.
Leaves lanceolate, entire. Flower cluster long and loosely flowered.
Flowers showy, drooping. Corolla tube slender, scarlet, somewhat
bearded in the throat. Sterile filament beardless. Cultivated from
Mexico.
V. GRATIOLA L.
Low herbs, growing in wet- or damp ground. Leaves oppo-
site, sessile. Flowers axillary and solitary, peduncled. Calyx
5-parted, usually with 2 bractlets at the base. Corolla some-
what 2-lipped. Perfect stamens 2. Stigma enlarged or 2-lipped.
Pod 4-valved, many-seeded.220
KEY AND FLORA
1. G. virginiana L. Stem cylindrical, 4-10 in. long, branching from
the base. Leaves f-lj in. long, varying from lance-oblong to spatu-
late. Corolla pale yellow, tinged with red. Common in muddy soil,
along brooksides, etc.
VI. VERONICA L.
Herbs or shrubs. Lower leaves or all the leaves opposite,
rarely whorled. Flowers in axillary or terminal racemes, rarely
solitary. Calyx usually 4-parted. Corolla wheel-shaped or some-
what bell-shaped ; limb usually 4-cleft, spreading, the side lobes
commonly narrower. Stamens 2, inserted on the corolla tube
at the sides of the upper lobe, projecting. Stigma somewhat
knobbed. Capsule generally flattened, often notched at the
apex, 2-celled, few-many-seeded.
1.	V. americana Schwein. Brooklime. A perennial, smooth herb,
somewhat prostrate below but the upper parts of the stem erect,
8-15 in. high. Leaves 1-2 in. long, lance-ovate or oblong, serrate,
short-petioled. Racemes 2-4 in. long, axillary and opposite. Corolla
wheel-shaped, blue. Capsule swollen, roundish. Muddy soil about
springs and brooks.
2.	V. officinalis L. Common Speedwell, Gypsy Weed. Peren-
nial. Eoughish-downy, with the prostrate stems spreading and root-
ing. Leaves wedge-oblong- or nearly so, obtuse, serrate, somewhat
petioled. Racemes dense, of many pale bluish flowers. Capsule
rather large, inversely heart-shaped and somewhat triangular. Dry
hillsides, open woods and fields.
3.	V. serpyllifolia L. Thyme-Leaved Speedwell. Perennial;
smooth or nearly so; branching and creeping below, but with nearly
simple ascending shoots, 2-4 in. high. Leaves slightly crenate, the
lowest ones petioled and roundish, those farther up ovate or oblong,
the uppermost ones mere bracts. Raceme loosely flowered. Corolla
nearly white or pale blue, beautifully striped with darker lines. Cap-
sule inversely heart-shaped, its width greater than its length. Damp,
grassy ground; a common weed in lawns.
4.	V. peregrina L. Purslane Speedwell. A homely, rather
fleshy, somewhat erect-branched annual weed, 4-9 in. high. Lowest
leaves petioled, oblong, somewhat toothed ; those above them sessile,
the uppermost ones broadly linear and entire. Flowers solitary, in-
conspicuous, whitish, barely pediceled, appearing to spring from
the axils of the small floral leaves. Corolla shorter than the. calyx.
Capsule roundish, barely notched, many-seeded. Common in damp
ground, in fields and gardens.FIGWORT FAMILY
221
VII. CASTILLEJA Mutis.
Herbs parasitic on tlie roots of other plants. Leaves alter-
nate ; the floral ones usually colored at the tip and more showy
than the flowers. Flowers yellow or purplish in terminal leafy
spikes. Calyx tubular, flattened, 2-4-cleft. Corolla tube in-
cluded within the calyx; upper lip of the corolla very long,
linear, arched, and inclosing the stamens, 2 of which are long
and 2 short. Ovary many-ovuled.
1.	C. coccinea Sprengel. Scarlet Painted Cup, Paint Brush,
Indian Pink, Prairie Fire, Wickakee. A hairy, simple-stemmed
herb, annual or biennial. Root leaves clustered, obovate or oblong;
stem leaves cut; floral leaves 3-5-cleft and bright scarlet (occasion-
ally yellow) toward the tips, as though dipped in a scarlet dye. Calyx
nearly as long as the pale yellow corolla, 2-cleft. The spikes are often
very broad, making this one of the most conspicuous of our native
flowers. Damp, sandy ground, or on bluffs near streams ; sometimes
in marshes.
2.	C. sessiliflora Pursh. Downy Painted Cup. Perennial; stem
leafy, 6-15 in. high, covered with ash-colored down. Lowest leaves
linear and entire, upper ones usually deeply cleft into narrow seg-
ments; floral leaves green, like the upper stem leaves. Calyx lobes
more deeply cleft on the lower than on the upper side, linear-lanceo-
late. Corolla yellowish, nearly 2 in. long; upper lip about twice the
length of the lower one. On prairies AV. and S.AV.
VIII. PEDICULARIS L.
Perennial herbs, with the lower leaves pinnately cut and
the floral ones reduced to bracts. Flowers spiked. Corolla
markedly 2-lipped; the upper lip much flattened laterally and
arched, the lower lip spreading, 3-lobed. Stamens 4, beneath
the upper lip. Capsule 2-celled, tipped with an abrupt point,
several-seeded.
1. P. canadensis L. Common Lousewort. Hairy, with clustered
simple stems, 1 ft. high or less. Leaves petioled, the lowermost ones
pinnately parted, the others somewhat pinnately cut. Spike short,
closely flowered, and leafy-bracted. Calyx split down the front.
Corolla greenish-yellow and purplish, with its upper lip hood-like,
curved under, and with 2 awl-like teeth near the end. Capsule flat,
broadly sword-shaped. Knolls and openings among thickets.222
KEY AND FLORA
91. BIGNONIACEAE. Bignonia Family
Trees or slirubs, often twining or climbing, rarely herbs.
Leaves 'usually opposite, without stipules. Flowers showy,
zygomorphic. Corolla tubular, with a widened throat and a
5-lobed limb. Stamens usually 2 long and 2 short, or only 2.
Ovary free from the calyx, 2-celled or rarely 1-celled, with
many ovules. Fruit a capsule ; seeds large, winged.
I. TECOMA Juss.
Woody vines, climbing by aerial rootlets. Leaves compound,
odd-pinnate. Flowers large, in terminal clusters. Calyx bell-
shaped, unequally 5-toothed. Corolla funnelform, enlarged
above the calyx, 5-lobed, slightly 2-lipped. Stamens 4, 2 long
and 2 short. Capsule slender, spindle-shaped, slightly com-
pressed contrary to the partition, 2-valved, dehiscent. Seeds
winged.*
1. T. radicans Juss. Trumpet Flower, Trumpet Creeper.
Stems climbing high by numerous rootlets; bark shreddy. Leaves
deciduous, petioled; leaflets 9-11, ovate to ovate-lanceolate, ser-
rate, short -stalked, smooth or slightly downy. Flowers in short,
terminal racemes or corymbs. Calyx tubular, f in. long. Corolla 2-3
in. long, scarlet without, yellow within, the lobes spreading. Capsule
5-6 in. long, curved, often persistent through the winter. Seeds
broadly winged. On borders of fields and in woods S.; often cul-
tivated.*
II. CATALPA Scop.
Small trees. Leaves large, opposite, simple, petioled, decid-
uous. Flowers large and showy, in terminal panicles. Calyx
irregularly 2-lipped. Corolla tubular-bell-shaped, oblique, 5-
lobed, 2-lipped. Fertile stamens 2, sterile stamens 3, short.
Fruit a linear, 2-valved, many-seeded capsule. Seeds winged.*
1. C. bignonioides Walt. Catalpa. A small tree with thin,
rough gray balk, and light, soft but exceedingly durable wood.
Leaves long-petioled, heart-shaped, entire or palmately 3-lobed,
taper-pointed at the apex, palmately veined, downy. Branches of
the panicle in threes; flowers large, 1-lf in. long, white, variegated
with yellow and purple. Corolla lobes undulate or crisped. CapsuleBROOM RAPE FAMILY
223
very slender, 1 ft. or more in length, pendulous. Seeds with long
fringed wings. On margins of rivers and swamps S.; often cultivated.*
2. C. speciosa Warder. Catalpa. A tall tx-ee with very durable
wood. Leaves large, heart-shaped, taper-pointed. Corolla about 2 in.
long, almost white, but slightly spotted ; tube inversely conical; limb
somewhat oblique, its lower lobe notched. Pod rather stout. Rich,
damp woods, especially S. W.; often cultivated.
HI. BIGNONIA L.
Woody vines. Leaves opposite, compound, usually tendril-
bearing. Flowers large, in axillary clusters. Calyx cup-shaped,
truncate, or undulate-toothed. Corolla spreading-tubular, some-
what 2-lipped, the lobes rounded. Stamens 4, 2 long and 2 short.
Capsule linear, flattened parallel with the partition, the two
valves separating from the partition at maturity; seeds flat,
broadly winged.*
1. B. capreolata L. Cross Vink. Stem climbing high, a trans-
verse section of the older stems showing a conspicuous cross formed
by the 4 medullary rays; branches smooth. Leaves evergreen, petr-
oled; leaflets 2, ovate, taper-pointed with a blunt apex, heart-shaped
at the base, entire, stalked; upper leaflets transformed into branching
tendrils. Flowers numerous, short-peduncled. Corolla 2 in. long, red-
dish-brown without, yellow within. Capsule 6 in. long, flat, the valves
with a prominent central nerve; seeds broadly winged on the sides,
short-winged on the ends. Common in woods S.*
92. OROBANCHACE2E. Broom Rape Family
Leafless brownish root parasites ; rootstock often tuberous,
naked or scaly ; stem usually stout, solitary, scaly. Flowers
spiked or racemed. Sepals 4-5, free from the ovary. Corolla
hypogynous, not actinomorphic, the tube curved, the limb 2-
lipped. Stamens 4 (2 long and 2 short), inserted on the corolla
tube; anthers 2-celled, the cells spurred at the base. Ovary
1-celled, of 2 carpels j style simple; stigma 2-lobed; ovules
many. Capsule 1-celled, 2-valved, few-many-seeded; seeds
very small.
I. CONOPHOLIS Wailr.
Stems often clustered, stout, covered with scales which
overlap, the uppermost ones each with an axillary flower,224
KEY AND FLORA
thus forming a spike. Calyx irregularly 4-5-cleft, split down
the lower side. Corolla swollen below, decidedly 2-lipped, the
upper lip arched. Stamens projecting.
1. C. americana Wallr. Squawroot, Cancer Root. Stems 3-6
in. high, yellowish or yellowish-brown. Flowers numerous, incon-
spicuous. Corolla dirty white or pale brown. In oak woods; not very
common.
II. OROBANCHE L. (THALESIA)
Brownish or whitish plants, with naked scapes borne on
scaly, mostly underground, stems. Calyx regular, 5-cleft.
Corolla 5-lobed, slightly irregular. Stamens not projecting
from the corolla tube.
1.	0. uniflora L. One-Flowered Cancer Root. Slightly cov-
ered with clammy down. Stems very short-branched, each with 1-3
1-	flowered scapes 3-5 in. high. Calyx lobes lance-awl-shaped, half
as long as the corolla. Corolla yellowish-white, veiny, purple-tinged;
palate with 2 yellow bearded ridges. Damp woods.
2.	0. fasciculata Nutt. Stem scaly, upright, 3-4 in. high above
ground and generally longer than the numerous 1-flowered peduncles.
Calyx lobes short, triangular. Parasitic on wild species of Artemisia,
etc., in sandy and loamy soil NAY. and AY.
93. ACANTHACEiE. Acanthus Family
Herbs or shrubs. Leaves opposite or whorled, without
stipules. Flowers zygomorphic, usually with large bracts.
Calyx of 4 or 5 unequal segments which considerably over-
lap each other. Corolla 4-5-parted and usually more or less
2-	lipped. Stamens usually 2 long and 2 short, sometimes only
2. Ovary free from the calyx. Fruit usually a capsule. Seeds
not winged. A large family, mostly tropical, with only a few
insignificant wild species in the northern United States.
I. DIANTHERA L.'
Perennial herbs ; stem smooth. Leaves opposite, entire or
toothed. Flowers axillary, solitary or'clustered, zygomorphic.
Calyx 5-parted. Corolla 2-lipped ; upper lip erect, concave,
entire or notched; the lower prominently veined, spreading,PLAXTAIX FAMILY
225
3-lobed. Stamens 2, inserted in the throat of the corolla.
Ovary 2-celled, 4-ovuled; style simple, acute. Capsule flat-
tened, narrowed below into a little stalk.*
1. D. americana L. Water Willow. Stem erect, slender, 2-3 ft.
high. Leaves lanceolate to linear-lanceolate, taper-pointed at the
apex, narrowed below to the sessile or short-petioled base. Flowers
bracted, in short spikes, on peduncles as long as the leaves. Corolla
pale blue or purple, the tube as long as the lips, lower lip wrinkled.
Capsule about the length of the calyx. In water, S.*
n. RUELLIA L.
Perennial herbs; stems swollen at the joints and often
between them, somewhat 4-angled. Leaves sessile or short-
petioled, mostly entire. Flowers axillary, solitary or clustered,
showy, white, blue, or purple. Calyx 2-bracted, 5-parted, the
divisions linear and awl-shaped. Corolla tube slender, often
much elongated, the limb spreading, nearly equally 5-lobed.
Stamens 4 (2 long and 2 short), included or slightly projecting.
Style slender. Capsule slender, narrowed below, 4-12-seeded.*
1.	R. ciliosa Pursh. Hairy Ruellia. Stem erect, rather stout,
often few-branched above, covered with white hairs, 4-30 in. high.
Leaves oblong to ovate, acute or obtuse at the apex, narrowed and
mostly sessile at the base, hairy-fringed. Flowers pale blue, solitary
or 2-3 together. Calyx lobes bristle-shaped, half the length of the
corolla tube. Tube of the corolla 2 in. long. Capsule shorter than
the calyx, smooth, 8-12-seeded. A very variable species, the flowers
often without a corolla. In dry woods and fields S.*
2.	R. strepens L. Smooth Ruellia. Stem erect, slender, usually
simple, smooth or hairy, 1-3 ft. high. Leaves ovate to obloug, acute
at the apex, narrowed below into a short petiole. Flowers solitary or
in small clusters, sessile or short-peduncled. Calyx lobes shorter than
the tube of the corolla, downy oi^fringed. Corolla blue, the tube 11—2
in. long, the limb 1-1^ in. wide. Capsule usually longer than the
calyx, smooth, 8-12-seeded. The later flowers often without a corolla.
On rich, dry soil.*
94. PLANTAGINACEJE. Plantain Family
Annual or perennial scape-bearing herbs. Leaves usually
all basal, with parallel ribs. Flowers small, green, usually226
KEY AND FLORA
spiked, regular and bisexual (Fig. 28). Sepals 4, persistent.
Corolla hypogynous, salver-shaped, thin and dry; lobes 4,
spreading. Stamens 4, usually
inserted on the corolla tube;
filaments thread-like; anthers
large and versatile. Ovary free,
usually 2-4-celled ; style thread-
like. Fruit a 1-4-celled, 1 or
more seeded membranous cap-
sule, which splits open trans-
versely, the top coming off
like a lid.
PLANTAGO L.
Characteristics of the genus
as given above for the family.
1. P. major L. Plantaix. Per-
ennial, from a very short rootstock.
Leaves ovate to oval, strongly 5-9-
ribbed, acute or obtuse at the apex,
rounded at the base into a long,
concave petiole, entire or toothed,
smooth or slightly downy. Scape
taller than the leaves, downy, spike
densely hoovered; bracts short, ovate. Flowers perfect. Stamens 4,
projecting. Capsule ovoid, about twice the length of the calyx, 5-16-
seeded; seeds angled and with a netted outer coat. Common in
dooryards*
Fig. '28. Flowers of plantain (Plan-
tago lanceolata), six times natural
size
A, earlier stage, pistil mature, sta-
mens not yet appearing outside tlie
corolla; B, later stage, pistil with-
ered, stamens mature
2.	P. Rugelii Decaisne. Leaves as in P. major, but smaller and
thinner. Spikes less dense, usually drawn out to a slender point.
Capsule 4-10-seeded ; seeds oval, the outer coat not netted. In fields,
woods, and waste ground.
3.	P. lanceolata L. Rib Grass. Biennial or perennial; soft-hairy
or nearly smooth. Leaves numerous, lanceolate to elliptical, acute,
long-petioled, strongly 4—5-ribbed, entire or toothed. Scapes much
longer than the leaves, striate-angled, 1-2 ft. high; spike short and
dense. Bracts and sepals ovate. Corolla smooth. Capsule longer
than the calyx, 2-seeded. Naturalized from Europe; common in
meadows.*MADDER FAMILY
227
4.	P. Purshii R. & S. Annual. White-woolly or silky. Scapes
slender; leaves linear, usually 3-nerved; spikes dense, cylindrical, and
very woolly ; bracts stiff, as long as the flowers or slightly longer.
Capsule 2-4-seeded, somewhat longer than the calyx. On dry prairies
and plains W. and S.W.
5.	P. aristata Michx. Large-Bracted Plantain. Annual.
Leaves broadly linear, entire or sparingly and finely toothed, nar-
rowed below into a margined petiole, smooth or silky-downy. Scape
longer than the leaves, G-10 in. high; spike dense. Bracts linear,
1-1 in. long. Stamens 4. Capsule 2-seeded, longer than the calyx.
Common on dry soil *
6.	P. heterophylla Nutt. Many-Seeded Plantain. Annual.
Leaves linear, fleshy, entire or with a few spreading teeth, smooth
or slightly downy. Scapes slender, 3-0 in. high; spike very slender,
many-flowered, the lower flowers often scattered. Bracts ovate, longer
than the sepals. Stamens 2. Capsule twice the length of the calyx,
many-seeded. Common in cultivated ground, especially S.*
95. RUBIACEAI. Madder Family
Herbs, shrubs, or trees. Leaves opposite and entire, with
stipules between them, or appearing whorled since the stipules
resemble the leaves. Flowers epigynous, always bisexual, fre-
quently dimorphous (as in Houstonia, Mitchella, and Bou-
vardia). Limb of the calyx 3-6-toothed. Corolla regular,
inserted on the calyx-tube, as many-lobed as the calyx. Sta-
mens equal in number to the divisions of the corolla. Ovary 2
or more celled. A very large and important family, of which
many of the noteworthy species, for instance the coffee shrub
and the cinchona tree, are natives of warm or tropical climates.
I. GALIUM L.
Annual or perennial herbs ; stems slender, 4-angled. Leaves
appearing whorled. Flowers small, in axillary or terminal
cymes or panicles, bisexual or rarely dioecious. Calyx tube
short, the teeth minute or wanting. Corolla wheel-shaped, 3-
4-lobed. Stamens 3-4, short. Ovary 2-celled ; styles 2, short,
united below. Fruit 2 united, sometimes fleshy, 1-seeded car-
pels, which do not split open.*228
KEY AND FLORA
1.	G. Aparine L. Goose Grass. Annual; stem weak, decumbent,
sharply 4-angled and with backward-pointing prickly hairs, widely
branched, 2-4 ft. long. Leaves 6-8 in a whorl, oblanceolate, prickly-
hairy on the margins and midrib. Peduncles axillary, longer than
the leaves, 1-3-flowered; flowers white. Fruiting pedicels erect;
fruit dry, covered with hooked bristles. In waste places.*
2.	G. circaezans Miehx. Wild Licorice. Perennial; stems sev-
eral, erect, smooth or downy, 12-18 in. high. Leaves 4 in a whorl,
oval to ovate, obtuse at the apex, strongly 3-nerved, downy. Cymes
long-peduncled, repeatedly branched. Flowers nearly sessile, greenish-
purple; pedicels at length recurved. Fruit with hooked bristles. In
dry, open woods S. Easily recognized by the sweet, licorice-like taste
of the leaves.*
3.	G.borealeL. Northern Bedstraw. Perennial; stem smooth,
erect, 1-2 ft. high. Leaves in fours, linear-lanceolate, 3-nerved.
Flowers bright white, in compact cymes, grouped in a dense panicle.
Fruit usually with minute bristles. In rocky soil along banks of
streams, especially N.
4.	G. concinnum T. & G. Shining Bedstraw. Stems slender,
smooth, shining, commonly much branched, 6-12 in. high, often
with the angles minutely roughened. Leaves usually in sixes, linear
or nearly so, often slightly cuspidate. Flowers small, white, in open
cymes. Fruit small, smooth. Dry hills and woodlands.
5.	G. asprellum Miehx. Rough Bedstraw. Perennial; stem
branching, weak, 3-5 ft. long, often reclining on bushes, with many
hooked prickles directed backwards. Leaves usually in sixes, or on the
branches in fours or fives, narrowly oval to lanceolate or oblanceolate,
cuspidate, with midribs and margins almost prickly. Flowers white,
in several-many-flowered cymes. Fruit smooth. In rich, moist soil.
6.	G. triflorum Miehx. Perennial; stems reclining or prostrate,
angles rough-bristly. Leaves mostly in sixes, lance-oblong, mucro-
nate. Flowers usually in threes, on slender peduncles. Woodlands,
especially N.
7.	G. hispidulum Miehx. Bedstraw. Perennial, from yellow
roots; stems diffusely branched, smooth or slightly roughened,
downy at the joints, erect or decumbent, 1-2 ft. long. Leaves 4 in
a whorl, narrowly oval, acute, rough on the margins and mid-vein.
Peduncles 1-3-flowered; flowers white; pedicels becoming reflexed.
Fruit a bluish-black, roughened berry. On dry, sandy soil.*
II. MITCHELLA L.
A pretty, trailing, evergreen herb. Leaves roundish-ovate,
petioled. Flowers fragrant, white or pinkish, dimorphous,MADDER FAMILY
229
growing in pairs, joined by their ovaries. Calyx 4-toothed.
Corolla funnel-shaped, with the lobes bearded within. Sta-
mens 4, short. Style 1; stigmas 4, slender. Fruit double,
composed of the united ovaries; really a drupe, containing
8 seed-like, bony nutlets, ripening into tasteless scarlet berries,
which cling to the plant through the winter.
1. M. repens L. Partridge Berry, Squaw Vine, Two-Eye
Berry. Common in dry woods, especially under evergreen conif-
erous trees.
III. BOUVARDIA Salisb.
Smooth perennials. Leaves lanceolate, thiekish. Calyx 4-
lobed, the divisions slender. Corolla with a long and narrow
or rather trumpet-shaped tube, and spreading, 4-lobed limb.
Anthers 4, inserted in the throat of the corolla, almost ses-
sile. Stigmas 2, flat. Capsule globular, 2-celled, many-seeded.
Flowers dimorphous.
1.	B. triphylla Salisb. Three-Leavf.d Bouvardia. Somewhat
shrubby. Leaves nearly smooth, ovate or oblong-ovate; the lower
ones in threes, the upper ones sometimes in pairs. Corolla scarlet
and slightly downy outside.
2.	B. leiantha Benth. Downy-Leaved Bouvardia. Leaves rather
downy. Corolla deep scarlet, smooth outside.
Both species cultivated from Mexico; in greenhouses.
IV. HOUSTONIA L.
Annual, biennial, or perennial herbs; stems erect or dif-
fuse. Leaves entire; stipules often only a line connecting the
bases of opposite leaves. Flowers small, solitary or clustered,
dimorphous, the stamens projecting and the style short in
one form, while in the other the stamens are short and the
style projecting. Calyx 4-toothed, persistent. Corolla wheel-
shaped to funnelform, 4-lobed. Stamens 4. Ovary 2-celled;
style slender; stigmas 2. Fruit a 2-celled, few-many-seeded
capsule, opening at the apex, free from the calyx.#
1. H. cffirulea L. Bluets, Innocence, Quaker Ladies, Eye-
bright. Perennial, from very slender rootstocks; stems tufted,
erect, smooth, forking, 3-6 in. high. Leaves sessile, often hairv-
fringed, the lower spatulate, the upper lanceolate. Flowers solitary,230
KEY AND FLORA
on slender axillary peduncles. Calyx small. Corolla salverform,
blue or white, yellow in the throat, smooth. Capsule laterally com-
pressed, 2-lobed, shorter than the calyx. Common on open ground.*
2.	H. patens Ell. Small Bluets. Annual; stem erect, branched
at the base, forking above, smooth, 2-4 in. high. Lower leaves oval
to ovate, petioled, the upper narrower and sessile. Flowers solitary,
on slender, axillary peduncles, blue or white. Calyx small. Lobes
of the corolla about as long as the tube. Stamens and style project-
ing or included. Capsule compressed, as long as the calyx. Common
on dry, open ground.*
3.	H. purpurea L. Large Bluets. Perennial; stem stout, erect,
simple or branched, smooth or downy, 4-angled, G-12 in. high. Leaves
ovate to ovate-lanceolate, sessile or short-petioled, 3-5-nerved, often
hairy-fringed on the margins. Flowers in terminal cymes, purple to
nearly white. Corolla funnelform, the tube longer than the limb,
hairy within. Stamens and style projecting or included. Capsule
compressed-globose, much shorter than the calyx. . In dry, open
woods.*
4.	H. longifolia Gaertn. Long-Leaved Bluets. Perennial; stem
erect, branched, smooth, 4-angled, 8-12 in. high. Leaves sessile, the
lower oblanceolate or spatulate, the upper linear, 1-nerved. Corymbs
terminal, few-flowered. Corolla light purple to white, the lobes much
shorter than the tube. Capsule compressed-globose, nearly as long as
the calyx. In dry, open woods.*
96. CAPRIFOLIACEAL Honeysuckle Family
Mostly shrubs. Leaves opposite, without true stipules.
Flowers epigynous, often zygomorphic. Corolla tubular or
wheel-shaped. Stamens usually as many as the corolla lobes
and inserted on the corolla tube. Fruit a berry, drupe, or
capsule.
I. DIERVILLA Mill.
Low, upright shrubs. Leaves taper-pointed, serrate. Flowers
in loose terminal or axillary clusters or cymes. Calyx with a
limb of 5 linear divisions. Corolla funnel-shaped, almost regu-
larly 5-lobed. Stamens f>. Ovary slender, 2-celled, ripening
into a 2-valved, many-seeded pod.
1. D. Lonicera Mill. Common Bush Honeysuckle. Bushy, 1-4
ft. high. Leaves ovate or oblong-ovate, petioled. Peduncles 1-3-
flowered. Pods tapering to a slender point. Rocks, especially N.HONEYSUCKLE FAMILY
231
2. D. japonica DC. Weigela. A stout, branching shrub, 3-6 ft.
high. Leaves broadly oval, acute at the apex, rounded at the base,
coarsely serrate, rough above, downy beneath, short-petioled. Flowers
spreading, funnelform, rose color, 1-1J in. long. Calyx lobes de-
ciduous. Corolla downy without,'the lobes spreading. Capsule oblong
or spindle-shaped. Seeds with netted wings. Introduced from Japan;
common in cultivation.*
II. LONICERA L.
Shrubs or woody vines. Leaves simple, usually entire, those
of a pair often appearing as if joined together at the base, so
that the stem seems to rise through them. Calyx tube ovoid,
5-toothed. Corolla tubular to bell-shaped, often knobbed at
the base or 2-lipped. Stamens -5. Ovary 2-3-celled, ovules
several in each cell; style slender; stigma knobbed. Fruit a
1-3-celled, 1-few-seeded berry.*
A
More or less upright hushes, not climbing.
1.	L. tatarica L. Tartarian Honeysuckle. A branching shrub,
5-8 ft. high. Leaves oval or ovate, heart-shaped, shining. Flowers
many, showy, rose-colored. Fruit consisting of 2 red berries ; some-
what united below' at maturity. Cultivated from Asia.
2.	L. canadensis Marsh. Early Fly Honeysuckle. A straggling
bush, 3-5 ft. high. Leaves ovate or oval, slightly heart-shaped, thin,
at first downy beneath. Flowers straw-yellow, on short, slender
peduncles. Corolla lobes nearly equal; tube pouched at the base.
Fruit 2 separate red berries.
B
Stems twining.
3.	L. japonica Thunb. Japan Honeysuckle. Stem twining
high; young branches downy. Leaves ovate to oblong, entire,
smooth above, pale and downy beneath, all short-petioled. Pedun-
cles axillary, 2-bracted, 2-flowered. Flowers white or pink, fading to
yellow', 2-lipped, the lips nearly as long as the downy tube. Stamens
and style projecting. Fruit black. Common in cultivation; intro-
duced from Japan.*
4.	L. sempervirens L. Coral Honeysuckle, Trumpet Honey-
suckle. Stem twining high. Leaves evergreen (in the South), oval
to oblong, obtuse, entire, smooth above, pale and often downy232
KEY AND FLORA
beneath ; the lower petioled, the upper pair nearly semi-orbicular and
joined at the base. Flowering spikes terminal, bearing several whorls.
Corolla about 2 in. long, slender, smooth; the limb short, nearly equally
5-lobed, scarlet without, bright yellow within. Stamens slightly pro-
jecting; fruit red. On low ground;'often cultivated.*
5.	L. Caprifolium L. European Honeysuckle. A moderately
high-climbing shrub. Leaves smooth and deciduous, several of the
upper pairs united at their bases to form a flattish disk or somewhat
cup-shaped leaf. Flowers in a single terminal whorl, very sweet-
scented. Corolla whitish, red, or yellow, 2-lipped, with the lips re-
curved. Cultivated from Europe.
6.	L. Sullivantii Gray. Yellow Honeysuckle. Stem somewhat
twining. Leaves oval to obovate, obtuse, entire, green above, with a
bloom beneath, the lower short-petioled, the upper sessile or joined
at the base. Flowers in crowded, terminal whorls, bright yellow, fra-
grant. Corolla tube slender, 1-1J in. long, bilabiate, 4-lobed, pubes-
cent within. Stamens and style projecting. On river banks and
hillsides; often cultivated.*
III. SYMPHORICARPOS Ludwig
Shrubs, Leaves sliort-petioled, deciduous. Flowers in axil-
lary clusters. Calyx tube globose, 4-5-toothed. Corolla bell-
shaped, 4-5-lobed, sometimes knobbed at the base, smooth or
hairy within. Stamens 4-5. Ovary 4-celled ; 2 of the cells with
a single fertile ovule in each, the other cells with several abor-
tive ovules; style slender; stigma knobbed or 2-lobed. Fruit
a 4-celled, 2-seeded berry.*
1. S. racemosus Michx., Var. laevigatus. Snoweerry. An orna-
mental shrub, 2-3 ft. high. Flowers iir loose terminal racemes, which
are often leafy. Corolla bell-shaped, much bearded inside, pinkish-
white. Stamens and style not projecting. Berries rather large, snow-
white, remaining long on the branches. Rocky banks, often cultivated.
IV. LINNJEA L.
A very small, slender, creeping evergreen shrub; branches
inclined, ending in a slender, erect, 2-flowered peduncle.
Leaves opposite, without stipules. Flowers nodding, on slen-
der pedicels, with 2 bractlets. Calyx tube ovoid ; limb 5-lobed.
Corolla nearly bell-shaped, 5-lobed. Stamens 4, inserted near
the base of the corolla; 2 of them longer than the other 2.HONEYSUCKLE FAMILY
233
Ovary 3-celled ; style thread-like ; stigma knobbed ; ovules
many in 1 cell, solitary in the 2 others. Fruit nearly globose,
1-seeded.
1. L. borealis L. Twin Flower. A beautiful, delicate plant.
Corolla pale pink, very fragrant. Moist woods, in moss and cold
bogs N.
V.	TRIOSTEUM L.
Coarse, hairy, perennial herbs. Leaves large, those of each
pair somewhat joined at the base, so that the stem appears to
rise through them. Calyx tube ovoid; divisions of the limb
leaf-like, lance-linear, persistent. Corolla knobbed at the base,
nearly equally 5-lobed. Ovary usually 3-celled, ripening into
a drupe with 3 nutlets.
1. T. perfoliatum L. Tinker Weed, Wild Coffee, Fevf.rwort,
House Gentian. Stem unbranched, soft-hairy, 2-4 ft. high. Leaves
spatulate-ovate, abruptly narrowed at the base, 4-7 in. long and 2-4
in. wide, bordered with a fringe of hairs. Flowers dark brownish-
purple. Corolla about ^ in. long, sticky-downy. Fruit ellipsoidal,
orange-colored when ripe. Common along fence rows and in rocky
woods.
VI.	VIBURNUM L.
Shrubs or small trees. Leaves simple, entire, dentate or
lobed, with or without stipules. Flowers small, white, in ter-
minal cymes ; the outer flowers of the cyifle sometimes greatly
enlarged and sterile. Calyx tube very small, 5-toothed. Corolla
wheel-shaped or bell-shaped, 5-lobed. Stamens 5, inserted in
the tube of the corolla. Ovary 1-3-celled, 1-3-ovuled, but only
1 ovule maturing ; style short, 3-lobed. Fruit a 1-seeded drupe,
with soft pulp.*
A
Flowers around the margin of the cyme without stamens or pistils,
large anil showy.
1. V. alnifolium Marsh. Hobblf.busii, Witch Hobble. A shrub
about 5 ft. high, with the branches reclining and often rooting and
forming loops (whence the popular names). Leaves very large,
roundish, abruptly taper-pointed, serrate, with a rusty down on the
petioles and veinlets. Cymes very broad and showy. Fruit red, not
eatable.284
KEY AND FLORA
2.	V. Opulus L., var. americanum. Cranberry Tree, IIigh-
Bush Cranberry. A handsome, upright shrub. Leaves 3-5-ribbed
and 3-lobed. Fruit bright red, juicy, very acid, and used as a sub-
stitute for cranberries. Common N. The form known as “ snow-
ball,” with all the flowers showy and sterile, is cultivated from Europe.
B
Flowers all small and bisexual.
3.	V. acerifolium L. Maple-Leaved Arrow'wood. A slender
shrub, 3-0 ft. high. Leaves broadly ovate to heart-shaped, palmately
veined and 3-lobed, serrate or nearly entire, petioled, downy, becom-
ing smooth above. Cymes peduncled, about 7-rayed, 2-3 in. wide;
sterile flowers none. Fruit oval, black; stone flat, 2-ridged on the
edges. In dry, open woods.*
4.	V. dentatum L. Arruwwood. A shrub 8-15 ft. high. Leaves
broadly ovate to oval, acute at the apex, rounded or heart-shaped
at the base, coarsely dentate, smooth above, hairy in the axils of the
veins beneath, short-petioled. Cymes long-peduncled, 7-rayed, 2-3
in. wide; sterile flowers none. Calyx smooth. Fruit globose, dark
blue ; stone compressed, grooved on one side. In rich, damp soil.*
5.	V. nudum L. Withe-Rod. A shrub 8-12 ft. high. Leaves
ovate to lanceolate, entire or slightly toothed, acute at both ends,
thick, smooth above, the veins prominent beneath; petiole short.
Cymes short-peduncled, 5-rayed; sterile flowers none. Fruit ovoid,
blue. Common in swamps.*
6.	V. Lentago L. Nannyberry, Sheepberry. A shrub or small
tree, sometimes 30 ff. high. Leaves ovate, sharply serrate, taper-
pointed, usually smooth on both sides. Flower clusters large com-
pound cymes. Fruit oval, 1 in. or more long, bluish-black, with a
bloom, eatable. In woods and on banks of streams.
7.	V. prunifolium L. Black Haw. A small tree, 15-20 ft. high.
Leaves oval to ovate, acute or obtuse at each end, finely and sharply
serrate, smooth and shining above, often slightly downy beneath;
petioles dilated and rusty-downy. Cymes sessile, large, 4-5-rayed;
sterile flowers none. Fruit oval, bluish-black, eatable. In rich, moist
woods.*
VII. SAMBUCUS L.
Shrubs with odd-pinnate leaves. Calyx limb minute or want-
ing. Flowers very many, small, white, in compound cymes.
Corolla with a small, somewhat urn-shaped tube, and a flattish,
spreading, 5-cleft limb. Stamens 5. Stigmas 3, sessile. Fruit
a globular, pulpy drupe, 3-seeded, appearing like a berry.YALE RIAN FAMILY
235
1.	S. canadensis L. Common Elder. Stems 5-10 ft. high, with
a thin cylinder of wood surrounding abundant white pith. Leaflets
o-ll, oblong, taper-pointed, smooth. Cymes flat and often very
large. Fruit purplish-black, insipid or almost nauseous, but some-
what used in cookery.
2.	S. racemosa L. Rf.d-Berried Elder. More woody, with
brown pith. Leaflets fewer, downy beneath, especially when young.
Cymes panicled and somewhat pyramidal. Fruit scarlet.
97. VALERLANACE2E. Valerian Family
Herbs, rarely shrubs. Leaves opposite, without stipules.
Flowers epigynous, small, usually not actinomorpbic, in fork-
ing cymes. Corolla funnel-shaped, the base often with a sac
or spur. Stamens 1-3 or 5, inserted at the base of the corolla
tube ; filaments slender, anthers versatile. Ovary cells 3 ; two
of them not ovule-bearing, the third with a single ovule hang-
ing from the top; style thread-like ; stigma blunt or 2-3-lobed.
Fruit small, not splitting open.
I. VALERIANA L.
Perennial, rarely annual, herbs. Basal leaves crowded ; stem
leaves opposite or whorled, entire or pinnately cut. Flowers
in eorymbed, headed, or panicled cymes. Limb of the calyx
consisting of several plumy bristles. Lobes of the corolla 5
or rarely 3-4, unequal. Stamens 3. Stigma knobbed. Fruit
flattened, ribbed, 1-celled, 1-seeded.
1.	V. edulis Nutt. An upright, straight-stemmed plant, 1-1 ft.
high. Leaves all thickish and closely fringed with short hairs; root
leaves linear-spatulate or lanceolate-spatulate. entire; stem leaves
pinnately parted, the 3-7 divisions long and narrow. Flowers almost
dicecious in a long, interrupted panicle. Corolla whitish. Root long
and stout, eaten by Indians. Low ground and wet prairies, especiallv
N.W.
2.	V. officinalis L. Garden Valerian. Plant smooth or hairy
below, strong smelling. Rootstock short. Leaves all pinnate ; basal
leaves long-petioled, soon withering; stem leaves 2—5 in. long, sessile,
the leaflets lanceolate, entire or serrate. Corolla pale pink. Root-
stocks strong-scented, used in medicine. Cultivated from Europe.236
KEY AND FLORA
II. VALERIANELLA Hill
Annual herbs; stem forking regularly. Leaves opposite, entire
or dentate. Flowers in crowded, terminal, bracted cymes. Calyx
limb toothed or wanting. Corolla white or purplish, funnelform,
5-lobed. Stamens 3. Style 3-lobed. Fruit 3-celled, 1-seeded.*
1.	V. Locusta Betcke. Lamb Lettuce. Stem erect, smooth, or
downy at the nodes, many times forked, 9-12 in. high. Basal leaves
tufted, spatulate to obovate, entire; the upper lanceolate, dentate,
sessile. Cymes short-peduncled, bracts linear. Flowers pale blue.
Fruit compressed, oblique. On rich soil in waste places. Some-
times cultivated for salad. Introduced from Europe.*
2.	V. radiata Dufr. Corn Salad. Stem erect, smooth above,
downy below, 2-4 times forked, 8-12 in. high. Lower leaves spatu-
late, entire; the upper lanceolate, clasping at the base, dentate.
Cymes compact; bracts lanceolate. Flowers white. Fruit ovoid,
downy, furrowed. On damp soil.*
98. CUCURBITACEiE. Gourd Family
Somewhat succulent, tendril-bearing, prostrate or climbing,
herbaceous plants. Leaves alternate, with stipules. Flowers
epigynous, dioecious or monoecious, often sympetalous. Calyx
limb (if present) 5-lobed. Corolla usually 5-lobed and with its
tube more or less united with the calyx tube. Stamens perigy-
nous or borne upon the corolla; the anthers usually joined in
long, serpentine ridges. Ovary 3-celled ; stigmas 2 or 3. Fruit
generally a pepo (like the melon, squash, and pumpkin), but
sometimes dry. Seeds commonly large and flat. A large family,
mostly of tropical plants, many with eatable fruit, but some
species poisonous.
I. CUCURBITA L.
Annual or perennial herbs ; stem trailing or climbing, 2-20
ft. long. Leaves angular-lobed; tendrils branching. Flowers
monoecious, solitary or in small clusters. Calyx 5-toothed, the
limb deciduous. Corolla bell-shaped, 5-lobed. Staminate flowers
with 3 stamens and no pistil; pistillate flowers with 1 pistil and
3 imperfect stamens. Style short; stigmas 3-5, each 2-lobed.
Fruit 1-celled, with numerous seeds on the 3 parietal placentae.*CAMPANULA FAMILY
237
1.	C. foetidissima LIBK. Missouri Gourd. Stem stout, rough
and hairy. Root very large, carrot-shaped. Leaves thick, triangular
heart-shaped. Flowers 3-4 in. long. Fruit globose or somewhat
obovoid, 2-3 in. in diameter. Dry soil W. and S.W.
2.	C. Melopepo L. Summer Squash. Stem rough-hairy, angled,
2-5 ft. long. Leaves broadly heart-shaped, angularly 3-5-lobed,
rough. Flowers yellow, short-peduncled. Fruit roundish, longitudi-
nally compressed, the margin smooth, wavy, or tubercular. Com-
mon in cultivation.*
3.	C. verrucosa L. Crookneck Squash. Stem rough-hairy, angled
and striate, 5-10 ft. long. Leaves cordate, deeply 5-lobed, very rough,
long-petioled. Flowers light yellow, long-peduncled. Fruit clavate,
the base often slender and curved, smooth or tuberculate, very variable.
Common in cultivation.*
II. CUCUMIS L.
Annual herbs; steins trailing, usually shorter and more
slender than in the preceding genus; tendrils not forked.
Leaves varying from entire or nearly so to deeply cut. Sterile
llowers in clusters, fertile ones solitary in the leaf axils.
Corolla of 5 acute petals, which are but little joined at the
base. Stamens not evidently united. Style short; stigmas 3,
each 2-lobed. Fruit rather long. Seeds not large, lance-oblong,
not margined.
1. C.sativusL. Cucumber. Leases somewhat lobed, the middle
lobe largest. Fruit more or less covered when young with rather
brittle, blackish prickles, which fall off as it ripens. Cultivated from
S. Asia. [Other varieties of the genus Cucumis are the muskmelon,
cantaloupe, and nutmeg melon. Other commonly cultivated genera
are Citrullus, the watermelon, and Lagenaria, the bottle gourd. Two
wild genera, Ecliinocyslis, the wild cucumber, and Sicyos, the star
cucumber, which blossom through the summer and autumn, are
common in the northern states and the Middle "West.]
99. CAMPANULACE1E. Campanula Family
Herbs, with milky juice. Leaves alternate, without stipules.
Flowers epigynous, actinomorphic, not clustered. Calj'x 5-
lobed. Corolla regular, bell-shaped, 5-lobed. Stamens 5, usu-
'ally free from the corolla and not united. Style 1, usually
hairy above; stigmas 2 or more. Fruit a capsule, 2 or more
celled, many-seeded.238
KEY AND FLORA
I. SPECULARIA Fabricius
Annual; stems slender, angled. Leaves entire or toothed.
Flowers axillary, regular, solitary or in small clusters, ses-
sile, bracted. Calyx tube slender, 3-5-parted. Corolla wheel-
shaped, 5-lobed. Stamens with the filaments flattened and
shorter than the anthers. Ovary 3-celled, many-ovuled; stig-
mas 3. Fruit a prismatic, 3-celled, many-seeded capsule.*
1. S. perfoliata A. DC. Specularia. Stem erect, simple or
branched from the base, angles roughened, 10-20 in. high. Leaves
ovate to lanceolate, acute at the apex, sessile, crenate or entire, the
upper bract-like. Flowers solitary or in pairs. Corolla blue, often
wanting. Capsule cylindrical, smaller above. In waste places.*
II. CAMPANULA L.
Annual, biennial, or perennial herbs. Flowers solitary,
racemed or spiked, regular, blue or white. Calyx 5-lobed or
parted. Corolla wheel-shaped to bell-shaped, 5-lobed. Stamens
5, free from the corolla, distinct; filaments dilated at the base.
Ovary 3-5-eelled, many-ovuled; style 3-parted. Capsule short,
bearing the persistent calyx lobes at its apex, many-seeded,
splitting open on the sides.*
1.	C. americana L. Tall Bellflower. Annual or biennial.
Stem erect, usually unbranched, 3-6 ft. high. Leaves varying from
ovate to lanceolate, serrate, 2',-6 in. long. Spike 1-2 ft. long. Corolla
wheel-shaped, light blue, about 1 in. in diameter. Moist, rich soil,
especially in thickets.
2.	C. rotundifolia L. Harebell. A slender, smooth, branching
perennial, 5-12 in. high. Root leaves broadly ovate-heart-shaped,
generally somewhat crenate, soon withering ; stem leaves varying
from linear to narrowly lanceolate, entire. Pedicels slender; flow-
ers solitary or somewhat racemed, the buds erect but the fully
opened flower drooping. Calyx teeth erect, awl-shaped. Corolla
bell-shaped, 1-1 in. long, its lobes short and recurved. Rocky hill-
sides, especially N.
3.	C. aparinoides Pursh. Marsh Bellflower. Stem angular,
unhranchfd, slender, weak, and leaning on the grass among which it
usually grows, the angles clothed with minute, backward-pointing
prickles. Leaves lance-linear, nearly entire. Flowers terminal, about
-J- in. long, white. Corolla bell-shaped. AYet meadows, in tall grass.COMPOSITE FAMILY
239
100. COMPOSITE. Composite Family
Flowers epigynous, in a dense head, on a common recepta-
cle, surrounded by an involucre composed of many bracts
(Fig. 29), with usually 5 stamens inserted on the corolla,
the anthers united into a tube which surrounds tjie style.
Fig. 29. Flower cluster and flowers of yarrow
A, flower cluster; B, section of flower cluster; C, a ray flower; D, a disk
flower, a, anthers; ch, chaff of disk; cl, disk flowers; o, ovary; rc, corollas
of ray flowers; s, stigmas; tc, corolla of tubular flower. (A, B, C, 7 times
natural size; D, 18 times natural size)
Calyx with its limb sometimes wanting; when present taking
the form of scales, bristles, etc., known as pappus (Fig. 30).
Corolla either strap-shaped (Fig. 29, rc) or tubular (Fig. 29, tc);
in the former case often 5-toothed, in the latter usually 5-
lobed. Style 2-cleft above. Fruit an akene, often provided
with means of transportation. This is the largest family of
flowering plants and among the most specialized for insect240
KEY AND FLORA
pollination. The genera of the northern United States are
divided into two suborders: I. Tubuliflor.e, corolla of
the bisexual flowers tubular and 5-lobed; II. Lig-uliflorje,
corollas all strap-shaped and flowers all bisexual.
Fig. 30. Akenes with various types of pappus
A, Rudbeckia, pappus wanting; B, Cichorium, pappus a crown of fine scales;
G', Coreopsis, pappus of 2 small scales; D, Helenium, pappus a crown of
conspicuous scales; E, Cirsiurn, pappus a tuft of plumose hairs; F, Lac-
tuca, pappus borne on a long beak
I. TUBULIFLORAJ 1
Corollas some or all of them tubular.
Rays white, pink, or purplish.
Rays many ; akenes flat; pappus wanting; low herbs. Beilis, I
Rays many; akenes cylindrical or winged, grooved; pappus
wanting; tall herbs or shrubby.	Chrysanthemum, X
Rays many; akenes flat; pappus of an outer row of minute
scales and an inner row of delicate bristles. Erigeron, II
Rays many; akenes cylindrical or ribbed; pappus wanting;
strong-scented, branching herbs.	Anthemis, IX
Rays few.	Achillea, VIII
1 The characters in this key are not necessarily true of all species in the
genera referred to, but only of those described below.COMPOSITE FAMILY
241
Rays yellow.
Disk purplish-brown.	Rudbeokia, IV
Disk gray.	Lepaehys, V
Disk yellow.
Involucre of 2 rows of bracts, the outer rather leaf-like.
Coreopsis, IT
Involucre of reflexed scales ; pappus of 3-8 scales.
Ilelenium, VII
Involucre of erect scales; pappus of abundant soft hairs.
Senecio, XI
Rays none, but the marginal flowers sterile and their tubular
corollas partly flattened like rays.	Centaurea, XIII
Rays none, and marginal flowers like the others; scales of the in-
volucre not prickly.	Antennaria, III
Rays none and marginal flowers like the others; scales of the in-
volucre overlapping in many rows, prickly-pointed.
Cirsium, XII
II. LIGULIFLOR-E
Corollas all strap-shaped.
Corollas blue (rarely pinkish);
akenes not beaked.
Cichorium, XIV
Corollas blue; akenes beaked.
Lactuca, XIX
Corollas yellow.
(a) Akenes truncate; pappus double,
of chaff and bristles.
Ivrigia, XV
(&) Akenes columnar; pappus of
tawny, rough bristles ; stem
scape-like.
Hieracium, XXII
(c) Akenes spindle-shaped, not
beaked; pappus of plumed
bristles. Leontodon, XVI
Fig. 31. Types of pappus hairs
A, smooth hair of dandelion; B,
plumose hair of fall dandelion;
C, rough or barbed hair of
hawkweed. (7 times natural
size)242
KEY AND FLORA
(d)	Akenes ovoid to spindle-shaped, long-beaked, 4—5-ribbed;
pappus white, soft, and abundant. Taraxacum, XVII
(e)	Akenes nearly as in XVII; pappus tawny.
Pyrrhopappus, XXI
(/) Akenes not flattened, with or without beak, 10-ribbed ; pappus
of abundant stiff, hair-like white bristles. Agoseris, XX
(7/) Akenes flattened, beaked; pappus soft, white, the hairs soon
falling off ; leafy-stemmed herbs.	Lactuca, XIX
(h) Akenes flattened, not beaked; pappus abundant, soft, white;
leafy-stemmed, spiny-leaved herbs.	Sonchus, XVIII
I. TUBULIFLORAi
I. BELLIS L.
Small herbs. Leaves usually all basal, petioled. Heads
solitary, disk yellow, ray flowers white or pink; involucre
bell-shaped; bracts in 1 or 2 rows, green ; receptacle conical.
Ray flowers many, in a single row, pistillate ; disk flowers
tubular, bisexual, 4-5-toothed; forks of the style short, thick,
tipped by roughened cones. Fruit flattened, obovate; pappus
wanting.
1.	B. integrifolia Michx. American Daisy. A branching annual
or biennial herb, 4-12 in. high. Upper leaves lanceolate or oblong,
the lower ones obovate-spatulate. Heads borne on slender peduncles;
rays violet-purple. Prairies, especially S.W.
2.	B. perennis L. English Daisy, Scotch Daisy. An apparently
stemless perennial. Leaves obovate-spatulate, smooth or hairy. Heads
J-l in. in diameter, very pretty, the rays delicate. Cultivated from
Europe.
II. ERIGERON L.
Herbs. Leaves usually sessile. Heads many-flowered, flat
or nearly hemispherical, the rays numerous, narrow, pistillate.
Scales of the involucre narrow and overlapping but little.
Akenes flattish, crowned with a single row of liair-like bristles,
or sometimes with shorter bristles or scales outside these.
Disk yellow, rays white, pinkish, or purple.
B. FI. species 5 (Leptilon).COMPOSITE FAMILY
243
1.	E. pulchellus Michx. Robin's Plantain. Perennial; soft-
hairy; stems sometimes throwing out offsets from the base; simple,
erect, 1-2 ft. high. Basal leaves obovate-obtuse, somewhat serrate ;
stem leaves few, lance-oblong, acute, clasping. Heads rather large,
1-9, on long peduncles, with 50-60 long, rather broad, bluish-purple
or reddish-purple rays. Thickets and moist banks.
2.	E. philadelphicus L. Perennial; rather hairy; stems slender,
about 2 ft. high. . Basal leaves spatulate and toothed; stem leaves
usually entire and strongly clasping, sometimes with a heart-shaped
or eared base. Heads several, small, long-petioled; rays exceedingly
numerous, thread-like, reddish-purple or flesh color. In damp soil.
3.	E. annuus Pers. Common Fleabane. Annual or biennial.
Stem grooved and stout, branching, 2-5 ft. high, with scattered
hairs. Lowest leaves petioled, ovate, coarsely toothed; those higher
up the stem successively narrower, sessile. Heads in a large, loose
corymb; rays short, white or purplish. Fields and waste ground.
4.	E. ramosus BSP. Daisy Fleabane. Annual or biennial.
Considerably resembling the preceding species, but with entire
leaves, smaller and less branched stem, smaller heads, and longer
rays. Fields and pastures.
5.	E. canadensis L. IIorsewekd, Botterweed, Colt’s Tail.
Annual; stem erect, 1-5 ft. high. Leaves linear, those of the stem
entire. Heads very numerous and small, panicled; the white rays
hardly longer than the pappus. A common and troublesome weed.
m. ANTENNARIA Gaertn.
Perennial woolly herbs. Leaves partly basal, the stem leaves
alternate. Heads small, many-flowered, dioecious; the flowers
all tubular. Involucre of thin, dry’, white or colored bracts,
imbricated in several series. Receptacle convex or flat, with-
out chaff. Pistillate flowers with very slender tubular corollas
and abundant pappus of hair-like, naked bristles, somewhat
united at the base; pappus of the sterile flowers thickened
and club-shaped at the tips. Akenes small, cylindrical or
flattish.
1. A. Parlinii Fernald. Stolons ascending, leafy throughout; stems
rather stout, at length 12-20 in. high, they and the stem leaves more
or less downy with purplish glandular hairs. Basal leaves and those
at the tips of the stolons at length smooth and bright green above;
lower stem leaves abundant, oblong or narrower, obtuse or nearly so.
Heads corymbed. Style at length crimson. Rich soil, frequently in
open woods.244
KEY AND FLORA
2.	A. plantaginifolia Richards. Common Everlasting, Pussy’s
Toes. Stolons ascending, leafy throughout; stems slender, 4-20 in.
high. Basal leaves and those at the tips of the stolons pale and very
downy or covered with cobweb-like hairs above; stem leaves scat-
tered, lanceolate, taper-pointed. Heads more or less closely corymbed.
Styles crimson. In dry soil, very common.
3.	A. solitaria Rydb. Stolons when well developed procumbent,
leafy only at the tip; stems 2-8 in. high. Basal leaves obovate-
spatulate, densely downy beneath, covered with cobweb-like hairs
above, but becoming smoothish; stem leaves few, small, lying close
to the stem. Heads solitary. Styles crimson. Rich wooded hillsides,
central and south central states.
IV. RUDBECKIA L.
Perennial or biennial. Leaves alternate, entire or lobed.
Heads radiate, long-peduncled. many-flowered; bracts imbri-
cated in 2-3 series, spreading; receptacle convex or long-con-
ical, with concave, chaffy scales. Ray flowers yellow, neutral;
disk flowers purple to brown, bisexual. Akenes smooth, 4-
angled, truncate. Pappus a few short teeth or wanting.*
1. R. hirta L. Cone Flower, Black-Eyed Susan. Annual or
biennial; stem erect, rough-hairy, simple or branched, 2-3 ft. high.
Leaves lanceolate to oblong, thick, obscurely serrate, rough-hairy,
3-ribbed; the lower petioled, the upper sessile. Heads few, long-
peduncled; bracts rough-hairy, spreading. Ray flowers 10-20, orange-
yellow; disk flowers purplish-brown. Chaff acute, hairy at the apex.
Pappus none. On dry, open ground.
V. LEPACHYS Raf. (RATIBIDA)
Perennial herbs. Leaves alternate, pinnately divided. Heads
radiate, long-peduncled, many-flowered; bracts few, small,
spreading. Receptacle columnar or slender, the chaff of con-
cave truncate scales. Ray flowers yellow or with brown at
the base, neutral; disk usually grayish.
1. L. pinnata T. & G. Gray Cone Flower. Stem slender, branch-
ing, often 4 i't. or more high, gray with minute close-lying hairs.
Leaves mostly large, pinnately 3-7-divided ; the basal ones with long
petioles, stem leaves sessile, the uppermost small. Disk oblong, gray
or at length brown. Rays 4-10, light yellow, drooping, often 2 in.
long. In dry prairie soil and borders of thickets.COMPOSITE FAMILY
245
2. L. columnaris T. & G. Prairie Cone Flower. Stem rough-
hairy, slender, usually branching from the base, 1-2 ft. high. Leaves
pinnately divided into oblong to narrowly linear segments. Disk
columnar, sometimes more than 1 in. long. Rays 4-10, drooping,
yellow or partly or entirely brownish-purple, as long as or somewhat
shorter than the disk. On dry prairies, especially W. and S.W.
VI. COREOPSIS L.
Annual or perennial herbs. Leaves opposite or the upper
alternate, entire or pinnately divided. Heads radiate, solitary
or eorymbed, many-flowered ; bracts in 2 rows of about 8 each,
the inner membranaceous and appressed, the outer narrower
and spreading; receptacle chaffy. Ray flowers neutral; disk
flowers tubular, bisexual. Akenes compressed, oval to oblong,
often winged. Pappus of 2 scales or bristles, or wanting.*
1.	C. tinctoria Rutt. Gakde.v Coreopsis. Annual; stem erect,
smooth, branched, 2-3 ft. high. Leaves 2-3 times pinnately divided,
the divisions linear; lower leaves petioled, the upper often sessile and
entire. Heads 1-1J in. wide, on slender peduncles; inner bracts
brown with scarious margins, outer bracts very short. Ray flowers
about 8, yellow with a brown base, 3-lobed at the apex. Akenes
linear. Pappus minute or none. Common in gardens.*
2.	C. lanceolata L. Tickseed. Perennial; stem slender, erect or
ascending, smooth or slightly downy below, simple, 9-15 in. high.
Leaves opposite, the lower spatulate to elliptical, sometimes lobed, on
long, hairy-fringed petioles; the upper lanceolate, sessile. Heads few,
on long peduncles ; bracts ovate-lanceolate, the outer narrower. Ray
flowers 6-10; rays 3-5-lobed, bright yellow. Akenes oval, broadly
winged, warty. Pappus of 2 teeth. On rich, dry soil, S. and E.*
3.	C. grandiflora Hogg. Large-Flowered Tickseed. Usually
perennial; stem smooth, commonly branched above, 1—3 ft. high.
Most of the leaves once or twice pinnately parted, the lower some-
times entire, on slender petioles; segments of most of the stem leaves
linear or thread-like. Heads usually several, 1J-2 in. in diameter, on
long peduncles; outer bracts lanceolate, narrower and shorter than
the inner ones. Rays 6-10, yellow. Akenes oblong, with broad wings
when ripe. In moist soil, especially S.W.
4.	C. auriculata L. Running Tickseed. Perennial; stem ascend-
ing or decumbent, weak, smooth, nearly simple, 6-15 in. long.
Leaves ovate to oval, entire or with 2-4 small and rounded lobes at
the base, downy, long petioled. Heads 1-11 in. wide, few or single;
outer bracts narrower than the inner. Rays 6-10, mostly 4-toothed246
KEY AND FLORA
at the apex; chaff as long as the flowers. Akenes oblong, the wings
narrow and thickened; pappus of 2 minute teeth. In rich woods.*
5.	C. palmata Nutt. Stiff Tickseed. Perennial; stem stiff,
smooth, little or not at all branched, very leafy, 1-3 ft. high. Leaves
3-cleft, broadly wedge-shaped, stiff; the lobes linear-oblong, middle
one often 3-lobed. Heads on short peduncles, few or solitary, 1J—2 in.
in diameter; bracts of the outer series narrower than the inner ones,
slightly shorter. Rays 6-10, bright yellow, broad, usually 3-toothed.
Akenes oblong, with narrow wings. Dry prairies and thickets W.
6.	C. verticillata L. Perennial; stem smooth, stiff, slender, branch-
ing freely, leafy, 1-2 ft. high. Leaves divided into 3 sessile leaflets,
the latter once or twice pinnately parted into narrowly linear or thread-
like divisions. Heads 1J-1J in. in diameter; outer bracts much nar-
rower than the inner ones. Rays 6-10, yellow. Akenes oblong, with
narrow wings. In dry or moist soil, sometimes cultivated.
VII.	HELENIUM L.
Annual or perennial. Leaves alternate, forming wings on
the stem. Heads radiate, peduncled, many-flowered; bracts in
2 series, the outer linear and spreading, the inner few and
scale-like ; receptacle naked, convex or oblong. Ray flowers pis-
tillate and fertile, or neutral, the rays wedge-shaped, 3-5-lobed;
disk flowers bisexual, tubular, 4-5-lobed. Akenes top-shaped,
hairy, ribbed; pappus of 4—5 entire, toothed or awned scales.*
1. H. nudiflorum Nutt. Sneezeweed. Perennial; stem slender,
erect, downy, branched above, 1-2 ft. high. Leaves lanceolate, entire
or slightly toothed, the lower petioled, the upper sessile. Heads nu-
merous. Ray flowers 10-15, neutral, yellow or yellow and brown;
disk flowers purple. Akenes hairy on the ribs; pappus of ovate,
minutely toothed, awned scales. Common on river banks S.*
VIII.	ACHILLEA L.
Perennial. Leaves alternate, pinnately divided. Heads with
ray flowers in a terminal corymb ; involucral bracts imbricated
in several series, the outer shorter; receptacle chaffy. Ray
flowers white or pink, pistillate and fertile; disk flowers bi-
sexual, tubular, 5-lobed. Akenes oblong, compressed, slightly
margined; pappus none.*
1. A. Millefolium L. Yarrow. Stems often clustered, erect from
a creeping rootstock, simple, downy or woolly, 1-2 ft. high. LeavesCOMPOSITE FAMILY
•247
lanceolate or oblong, the segments finely cut and divided,- smooth or
downy, the lower petioled, the upper sessile. Heads small, numerous,
in flat-topped corymbs; bracts downy. Ray flowers 4-5, white or
pink, rays 3-lobed at the apex. Common in old fields.*
IX.	ANTHEMIS L.
Aromatic or ill-scented herbs. Leaves finely pinnately
divided. Heads many-flowered, with ray flowers. Rays pistil-
late or neutral. Involucre of many small, dry, close-pressed
scales. Akenes nearly cylindrical, generally ribbed, barely
crowned or naked at the summit.
1.	A. Cotula L. Mayweed, Dog Fennel. Leaves irregularly cut
into very many narrow segments. Heads small, produced all summer.
Disk yellow. Rays rather short, white, neutral. A low, offensive-
smelling annual weed, by roadsides and in barnyards.
2.	A. arvensis L. Field Chamomile. Annual or biennial. Re-
sembling A. Cotula, but without offensive smell. Leaves less finely
once or twice pinnately parted. In fields and waste ground. Natu-
ralized from Europe.
X.	CHRYSANTHEMUM L.
Perennials, with toothed, pinnately cut or divided leaves.
Heads nearly as in Anthemis, except that the ray flowers are
pistillate.
1.	C. Leucanthemum L. Oxeye Daisy, Whiteweed, Bull's-Eye,
Sheriff Pink. Stem erect, unbranehed or nearly so, 1-2 ft. high.
Basal leaves oblong-spatulate, petioled, deeply and irregularly toothed ;
stem leaves sessile and clasping, toothed and cut, the uppermost ones
shading off into bracts. Heads terminal and solitary, large and showy,
with a yellow disk and many white rays. A troublesome but hand-
some perennial weed. Naturalized from Europe, chiefly E.
2.	C. frutescens L. Marguerite. Erect, branching, perennial,
woody below, smooth, and with a pale bloom. Divisions of the leaves
linear, with the uppermost leaves often merely 3-cleft bracts. Heads
long-pednneled, showy, with a yellow disk and large, spreading white
rays. Cultivated in greenhouses. From the Canary Islands.
XI.	SENECIO L.
Annual or perennial; stems often' hollow. Leaves alternate,
entire or pinnately divided. Heads with or without rays, in
terminal corymbs; bracts mostly in a single row, often with a248
KEY AND FLORA
few shorter ones at the base; receptacle naked or pitted. Ray
flowers yellow or orange, pistillate and fertile when present;
disk flowers tubular, bisexual. Akenes cylindrical or com-
pressed, not beaked or winged, 5-10-ribbed, downy; pappus
of numerous slender white hairs.*
1.	S. glabellus Poir. Butterwf.ed. Annual; stem erect, ridged,
hollow, often woolly when young and becoming smooth with age,
branched above, 1-3 ft. high. Leaves lyrate-pinnatifid, thin, the lower
petioled, the upper sessile. Heads radiate in a terminal corymb; bracts
linear, acute. Ray flowers about 12, yellow. Akenes slightly rough-
hairy on the angles; pappus rough, longer than the involucre. Com-
mon on low ground.*'
2.	S. aureus L. Golden Ragweed. Perennial; stems often
tufted, erect, slender, -woolly when young, branched above, 18-30 in.
high. Lower leaves broadly ovate, obtuse at the apex, heart-shaped
at the base, crenate, long-petioled; stem leaves lanceolate and often
pinnatifid, the upper small and sessile. Heads radiate, corymbed, on
slender peduncles. Ray flowers 8-12, bright yellow. Akenes smooth.
In wet soil; very variable.*
3.	S. tomentosus Michx. Woolly Ragweed. Perennial; woolly
throughout; stem stout, erect, mostly simple, 2-3 ft. high. Lower
leaves ovate to oblong, crenate or entire, obtuse, long-petioled; stem
leaves few, elliptical to oblanceolate, serrate or toothed, acute, sessile.
Heads radiate, J in. wide, on slender peduncles; bracts narrow, be-
coming smooth. Ray flowers 12-15, yellow. Akenes hairy. In damp
soil.*
XII. CIRSIUM Hill. (CARDUUS)
Biennial or perennial; stem erect, simple or branched.
Leaves alternate, prickly, often forming wings on the stem.
Heads discoid, terminal and solitary or corymbed, many-flow-
ered ; bracts overlapping in many series, the outer shorter,
usually spine-pointed; receptacle bristly. Corollas purplish
or nearly white, the tube slender, deeply 5-cleft. Akenes
oblong, 4-angled, smooth or ribbed; pappus of numerous
simple or plumose bristles. [Most of our commoner species
blossom in the late summer and autumn.]*
1. C. spinosissimum Scop. Yellow Thistle. Biennial or perennial;
stem erect, stout, woolly when young, becoming smooth, often purple,
branched, 1-3 ft. high. Leaves pinnately cut, with very spiny teeth,
mostly sessile and clasping, smooth and green on both sides. HeadsCOMPOSITE FAMILY
249
large, surrounded by a whorl of linear-oblong, comb-like leaves; in-
volucral bracts linear, ciliate, not spine-tipped. Flowers purple or
yellowish. On sandy soil E. and S.*
2. C. virginianum Michx. Early Wood Thistle. Stem woolly,
slender, little or not at all branched, 1-3 ft. high. Leaves lanceolate,
green above, covered beneath with dense white wool, the margins
beset with prickly bristles, entire or sinuate-lobed, the lower ones
sometimes pinnately cut into triangular-lanceolate lobes. Heads
small, purple, on long leafless peduncles; outer scales of the involucre
merely bristle-pointed. In dry woods and thickets.
XIII. CENTAUREA L.
Herbs. Leaves entire or cut, often spiny-toothed. Heads
single; involucre ovoid or globose; bracts closely overlap-
ping, often fringed, dry and membranaceous. Corollas all tubu-
lar^ oblique or 2-lipped, inflated above ; the outer ones usually
larger and neutral, the inner flowers bisexual; lobes 5, slender.
Akenes flattened; pappus hairs short, slender, rough.
1.	Cyanus L. Bachelor’s Button-. Stem erect, slender, grooved,
1-2 ft. high, somewhat branched. Leaves acute, sessile, narrow, entire
or few-lobed. Peduncles covered with cottony wool. Heads i-1 in.
in diameter, cobwebby. Ray-like flowers few, large, bright blue or
pink; those of the disk smaller. Cultivated from Europe and escaped
from gardens.
2.	C. americana Nutt. Prairie Star Thistle. Annual; stem
stout, little or not at all branched, 2-6 ft. high. Leaves entire or
minutely toothed, the basal and lower ones spatulate or oblong,
petioled, the upper narrower, sessile and mucronate. Heads solitary
at the summit of the stem or tips of the branches; involucre nearly
hemispherical, the bracts ovate or lanceolate, with comb-like ap-
pendages. Flowers pink or purple, the marginal ones ray-like. In dry
plains, especially SAY.
n. LIGULIFL0R2E
XIV. CICHORIUM L.
Perennial herbs with spreading branches; juice milky.
Leaves radical and alternate, toothed or pinnately cut. Heads
axillary; involucre cylindrical; bracts in 2 rows, the inner
row erect, united at the base, the outer shorter; receptacle
flattish. Corollas blue, pale pink, or yellow. Upper part of
the style and its slender arms hairy. Akenes crowded on the250
KEY AND FLORA
hardened receptacle, firmly covered by the stiff involucre,
obovoid or top-shaped, not beaked; pappus 1 or 2 rows of
short scales.
1. C. Intybus L. Chicory, Blue Dandelion, Blue Sailors.
Root very long, stout, and fleshy; stem 1-8 ft. high, angled and
grooved; branches straight and stiff. Basal leaves and lower stem
leaves runcinate ; upper stem leaves oblong or lanceolate, clasping,
those of the branches reduced to bracts. Flowers very showy, usually
bright blue, rarely pinkish-white. Introduced from Europe ; a trouble-
some weed in grass lands and common in waste places, particularly
in New England.
XV. KRIGIA Sehreber. (ADOPOGON)
Small, annual or perennial herbs. Leaves mostly basal,
toothed or lyrate. Heads several-many-flowered; scales of
the involucre about 2-rowed, thin. Akenes short, truncate ;
pappus in 2 rows, the outer one of thin, blunt, chaffy scales,
the inner one of slender bristles. Corollas yellow.
1.	K. virginica Willd. Annual; scapes usually 2-5 from one root,
slender. Leaves mostly lyrate, smooth and with a bloom, the earlier
ones rounded or spatulate. Scales of the involucre linear-lanceolate,
nearly equal, spreading. Akenes top-shaped, reddish-brown, crowned
with 5 wedge-obovate scales and 5 rough white bristles.
2.	K. Dandelion Nutt. Perennial, from slender tuber-bearing
roots; scapes leafless, 6-18 in. high. Leaves entire or nearly so,
varying from spatulate-oblong to linear-lanceolate. Akenes more
slender than in No. 1; pappus consisting of 10-15 small, oblong,
chaffy scales, and 15-20 bristles. In moist ground, especially S.
3.	K. amplexicaulis Nutt. Stem 12-18 in. high, often 2-3 from the
same root, mostly 2-forked or 3-forked at the summit. Basal leaves
3-6 in. long, lanceolate, entire, toothed or rarely pinnately cut, clasp-
ing at the base; stem leaves 1-3. Akenes and pappus about as in
No. 2. Moist banks.
XVI. LE0NT0D0N L.
Perennial, scape-bearing herbs ; juice milky. Leaves all
basal, toothed or pinnatifid, often runcinate. Heads on simple
or branched scapes, yellow ; bracts of the involucre many, in
several rows, the anther smaller ; receptacle flat, naked. Arms
of the style linear, obtuse, hairy. Akenes cylindrical, grooved,
transversely wrinkled; beak short; pappus hairs stiff, in 1
or 2 rows.COMPOSITE FAMILY
251
1. L. autumnalis L. Scape usually branching, 5-15 in. high,
bracted; peduncles enlarged above. Rootstock truncate. Heads
11—1 in. or more in diameter; involucre top-shaped or bell-shaped.
Pappus of a single row of tawny hairs. Fields and roadsides,
especially X.E. Naturalized from Europe.
XVII. TARAXACUM Haller
Stemless perennial or biennial herbs. Leaves in a flatfish
tuft, pinnately cut or runcinate. Head many-flowered, large,
solitary, yellow, borne on a hollow scape, which is short at
first but lengthens after flowering. Involucre composed of a
single row of long, erect inner scales, and a set of much shorter
ones outside and at the base of the former ones. Akenes cylin-
drical or spindle-shaped, with 4-5 rough ribs, the apex taper-
ing into a bristle-like beak which bears a short, broadly conical
tuft of soft white hairs.
1. T. officinale Weber. Dandelion'. Outer involucre reflexed:
inner involucre closing over the head, after the flowers are withered,
and remaining shut for some days, then opening and allowing the
akenes to form a globular head. Root stout, bitter, medicinal. Young
leaves eaten as a pot-herb (— greens ") in spring — the plant often cul-
tivated for the leaves by market-gardeners.
XVUI. SONCHUS L.
Annual or perennial. Leaves mostly toothed or pinnately
cut, prickly margined. Heads in corymbs or panicles ; bracts
in several series, the outer shorter ; receptacle naked. Flowers
yellow, rays truncate. 5-toothed at the apex. Akenes oval to
oblong, compressed, ribbed, truncate at the apex; pappus of
numerous soft white hairs.*
1.	S. oleraceus L. Sow Thistle. Annual: stem erect, branched,
smooth, 2-6 ft. high. Leaves spiny-toothed, the lower long-petioled,
very irregularly cut or pinnatifld, the upper clasping by an eared
base. Involucre downy when young. Akenes channeled and trans-
versely wrinkled. In waste places on very rich soil.*
2.	S. asper Till. Spiny Sow Thistle. Annual ; stem erect,
smooth, branched but little, 2-6 ft. high. Leaves undivided, spatu-
late to oblauceolate, fringed with spiny teeth; the lower narrowed
into a petiole, the upper clasping by an eared base, the ears rounded.252
KEY AND FLORA
Ileacls numerous; involucre glabrous. Akenes flattened, margined,
3-nerved on each side, smooth. In waste places.*
XIX. LACTUCA L.
Annual, biennial, or perennial; stems leafy. Leaves entire
to pinnately cut. Heads panicled ; involucre cylindrical ; bracts
unequal, overlapping in 2 or more rows, the outer shorter;
receptacle naked. Flowers blue, yellow, or white; rays trun-
cate, 5-toothed at the apex. Akenes compressed, ribbed, the
apex contracted into a slender beak, which is enlarged into a
disk bearing the soft, hairy, white or tawny pappus.*
1.	L. canadensis L. Wild Lettuce. Biennial; stem erect,
smooth, hollow, branched above, 3-10 ft. high. Leaves lanceolate
to spatulate, pale beneath, the lower petioled and pinnately cut, the
upper sessile, clasping, and nearly entire. Heads numerous, about
20-flowered ; flowers yellow. Akenes oval, flat, 1-ribbed on each side,
minutely roughened, about as long as the beak; pappus white. In
waste places.*
2.	L. acuminata Gray. Blue Lettuce. Stem very leafy, smooth,
panieulately branched above, 3-6 ft. high. Leaves ovate to lanceo-
late, taper-pointed, often hairy beneath; the lower on winged petioles
and often sinuate-lobed, the upper sessile. Heads racemed, oil diver-
gent and bracted peduncles ; flowers blue. Akenes slightly com-
pressed, beak very short; pappus white. In waste places.*
XX. AGOSERIS Raf.
Herbs, usually appearing stemless. Basal leaves tufted,
usually sessile. Head solitary, large, yellow or rarely purple,
on a naked or bracted scape ; bracts of the involucre overlap-
ping in 2 or 3 rows ; receptacle flat, naked or pitted. Akenes
smooth, 10-ribbed, with or without a beak; pappus of abundant
slender white bristles.
B. FI. species 1 (Nothocalais).
1.	A. cuspidata Steud. Scape 1 ft. or more high. Leaves lanceolate,
taper-pointed, woolly-margined. Involucral scales lanceolate, sharp-
pointed. Akenes beakless. Prairies and plains W.
2.	A. glauca Steud. Scape stout, 1-2 ft. high. Leaves varying
from linear to oblong', entire, dentate or pinnately cut. Heads 1-2
in. in diameter. Akenes beaked. Plains W.COMPOSITE FAMILY
253
XXI. PYRRHOPAPPUS DC. (SITILIAS)
Annual or biennial; stem erect, leafy below, nearly naked
above, smooth. Leaves oblong, toothed or pinnatifid. Heads
large, long-peduncled; involucre cylindrical or spreading, the
inner row of bracts erect, united at the base, the outer rows
shorter and spreading; receptacle naked. Flowers yellow;
rays truncate, 5-toothed at the apex. Akenes oblong, 5-ribbed,
narrowed above into a long and slender beak; pappus soft,
tawny, with a short, soft-hairy ring at the base.*
1. P. carolinianus DC. False Dandelion. Annual or biennial;
stem glabrous, furrowed, branched above, 2-3 ft. high. Lower leaves
lanceolate to oblong, entire, toothed or pinnatifid, narrowed into a
margined petiole ; the upper sessile, bract-like, entire. Heads few,
long-peduncled; peduncles and involucre sometimes finely downy;
inner bracts calloused at the apex, the outer awl-shaped and spread-
ing. Akenes much shorter than the thread-like beak. Common in
fields.*
xxn. HIERACIUM L.
Perennial herbs, often covered with glandular or star-shaped
hairs ; juice milky. Leaves alternate. Heads solitary, or in
corymbs or panicles; bracts of the involucre many, overlap-
ping, unequal; receptacle flatfish, naked, pitted. Corollas
yellow, rarely orange. Arms of the style slender and upper
part of the style hairy ; akenes angled or grooved, not beaked.
Pappus hairs in a single row, simple, stiff, tawny or brownish,
brittle. [Most of our commoner species bloom in the late
summer or autumn.]
1.	H. aurantiacum L. Orange Hieracium, Devil's Paint Brush.
Stem leafless or occasionally with 1 or 2 small sessile leaves, clothed
with long hairs. Basal leaves oblanceolate, hairy, 21-6 in. long.
Scapes S-24 in. high. Heads corymbed, about f in. in diameter,
orange-red. A common weed, naturalized from Europe.
2.	H. venosum L. Rattlesnake Weed. Stem scape-like, usually
leafless or nearly so, smooth, 1-2 ft. high. Basal leaves 2—5 in. long,
obovate or ovate-oblong, generally purple-veined. Heads rather large,
yellow, in a loose panicled corymb. Dry hills and roadsides, and in
pine woods E.GLOSSARY
OF TECHNICAL TERMS USED MAINLY IN THE FLORA
Abortive, imperfectly developed.
Actinomorphic, having radial sym-
metry.
Adventive, partially naturalized.
Appressed, lying flat throughout its
length, used of such parts as
bracts.
Awl-shaped, narrow and tapering
to a point.
Awned, having a bristle-like ap-
pendage.
Awnless, not awned.
Bisexual, having both stamens and
pistils in the same flower.
Caducous, falling away very early.
Capitate : (1) having a round head
like the stigma of a primrose;
(2) growing in heads.
Carpellary, relating to a carpel.
Chaff, small membranous scales,
such as are found on disks of
Composite.
Ciliate, having the margins fringed
with hairs or bristles.
Clasping, partly surroupding the
stem; said of the bases of leaves.
Claw, the narrowed base of a petal.
Cleft, cut halfway down.
Coated (bulbs), those with scales
whieh completely cover them, as
in the onion.
Cone, the fruit of pines, etc., with
ovule-bearing scales.
Connate, united; said of opposite
leaves which appear as if grown
together at their
bases.
Convolute, rolled up
lengthwise.
Cordate, heart-shaped.
Corm, a bulb-like,
fleshy stem or base Convolute
of a stem.
Crown, an inner appendage to a
petal or to the throat of the co-
rolla.
Deciduous, falling as petals do after
blossoming, or as leaves of most
trees except evergreens do.
Declined, directed obliquely.
Decumbent, reclining, but with the
summit somewhat erect.
Dehiscent, splitting into definite
parts.
Diffuse, spreading widely or loosely.
Dimorphous, occurring under two
forms, as in flowers with long
and with short styles.
Disk : (1) an outgrowth of the re-
ceptacle within the calyx or
within the corolla and stamens ;
(2) the central part of the head
(all but the rays) in Composites.
255256
KEY AND FLORA
Dissected, deeply divided or cut
into many segments.
Drupe, a stone fruit such as a peach
or a plum.
Equitant, leaves astride of those
within them, thus appearing in a
cross section like the diagram,
<«.
Even-pinnate, abruptly pinnate,
i.e. with no leaflet at the end.
Fascicle, a close cluster or bundle
of flowers, leaves, stems, or roots.
Fertile, capable of producing fruit;
fertile flowers, those which have
pistils.
Filiform, thread-shaped.
Fleshy, succulent, thick and full of
sap.
Funiculus, the little stalk which
connects a seed or ovule with the
placenta.
Gland : (1) a structure which secretes
something, as the knobs on the
hairs of sundew ; (2) any knob
or swelling.
Glume, one of the two sterile,
chaffy bracts at the base of a
grass spikelet.
Herbaceous, with no stem above-
ground which lives through the
winter, not woody
or shrubby.
Imbricate, overlap-
ping, as the seg-
ments of some
perianths in the Imbricate
bud. At least one segment must
be wholly outside and one wholly
inside.
Indefinite, too many to be easily
counted.
Indehiscent, not splitting open reg-
ularly.
Introduced, term applied to plants
purposely brought into a region
by man.
Involucrate, provided with an in-
volucre.
Keel, the two anterior and united
petals of a papilionaceous corolla.
Key, a winged fruit like that of the
ash or maple.
Limb, the border or spreading part
of a gamopetalous calyx or co-
rolla.
Lobed, having divisions, especially
rounded ones.
Lodicule, one of the very minute
scales immediately beneath each
flower in a grass spikelet.
Naturalized, term applied to plants
not natives of a region but thor-
oughly established there in a
wild condition.
Nerved, having simple or un-
branched veins or slender ribs.
Ob- (in composition), signifies in-
versely; as, obcordate, inversely
heart-shaped.
Odd-pinnate, pinnate with a sin-
gle leaflet at the end of the
midrib.GLOSSARY
257
Palate, a projection in the throat
of a corolla.
Palet, one of the bracts which
subtend the flowers in a grass
spikelet.
Papilionaceous, butterfly-shaped,
like the corolla of the sweet pea.
Papillose, covered with papillae or
minute projections, like the
human tongue.
Pappus, tufts of hair or other ob-
jects, representing the limb of the
calyx in Composites (Fig. 30).
Peltate, shield-shaped, that is with
the stalk attached somewhere
within the circumference of the
leaf or other organ.
Perfoliate, with the stem appar-
ently growing up through a leaf,
as in some honeysuckles.
Persistent, not deciduous.
Pinnatifid, pinnately cleft.
Pistillate, having pistils but not
stamens.
Plumose, feathered, as the pappus
of thistles (Fig. 31).
Pubescent, clothed with soft hair,
downy.
Punctate, marked with dots, de-
pressions, or translucent glands.
Reflexed, bent or turned abruptly
downward or backward.
Root parasite, a plant parasitic on
the roots of another.
Sagittate, arrow-shaped.
Scape, a leafless flower stalk aris-
ing from the ground, as in the
dandelion and cyclamen.
Scarious, thin, dry, and membra-
nous, not green.
Sessile, without a stalk.
Simple (stem), unbranched.
Spadix, a spike with a fleshy axis,
like that of the Indian turnip or
the “calla.”
Spathe, a large bract which incloses
a flower cluster, often a spadix.
Staminate, having stamens only.
Standard, the posterior petal of a
papilionaceous corolla.
Sterile: (1) barren, as a flower with-
out a pistil or an antherless sta-
men ; (2) staminate or male, said
of flowers.
Striate, marked with fine longitudi-
nal parallel lines.
Sub- (in composition), somewhat,
as subglobose.
Subtend, to extend beneath as a
bract in the axil of which a
flower is borne.
Succulent, fleshy or juicy.258
KEY AND FLORA
Three-ranked, with three vertical
rows on a stem or axis.
Throat, the top of
the tubular part
of a sympetalous
corolla.
Truncate, appearing
as if cut squarely
off, as the leaves
of the tulip tree.
Tubercled, covered
with warty
growths.
Tubercular, having
like
Two-lipped,
the limb
Utricle
Two-lipped
tubercles, or
a tubercle.
having
of the
calyx or corolla
divided into two
lip-like portions,
as in the Labiates.
Two - ranked, with
two vertical rows
on a stem or axis.
Utricle, a small bladdery ovary
wall.
Versatile, turning freely on its
support, as an anther on its
filament.
Whorled, arranged in a circle
around an axis, as the leaves of
some lilies.
Wings, the side petals of a papilio-
naceous flower.
Unisexual, having in each flower
only stamens or only pistils, not
both.
Zygomorphic, having bilateral sym-
metry, as the corollas of many
Leguminosce.INDEX
All names in italics are syuonyms. —the preferred names are in Roman type
Abies, 17
Abutilon, 158
Acanthaceae, 224
Acanthus Family, 224
Acer, 151, 152
Aceracese, 151
Achillea, 240
Aconitum, 90
Acorus. 25
Actaea, 90
Acuan, 129
Adder's-Tongue, 37
Adlumia, 98
Adopogon, 250
-Eseulus, 153
Agrostemma, 79
Aizoaceae, 70
Alder, 58
Alfalfa, 135
Alisma, 21
Alismaceae. 21
Allegheny Vine, 98
Allium. 34
Alnus, 58
Alsine, 78
Alum Root, 110
Alyssum, 101
Amaranth. 74
Amaranth Family, 74
Amaranthaceae, 74
Amaryllidaceae, 43
Amaryllis Family, 43
Amelanchier, 117
Amianthium. 33
Amorpha, 136
Amsonia, 193
Anacardiaceae, 148
Anagallis, 187
Androsace, 185
Anemone, 87
Anemone, Rue, 80
Anemonella. MS
Angiosperms, 20
Anonaceae, 94
Anthemis, 247
Antirrhinum, 218
Apocynaeeae, 192
Apocynum, 193
Apple, 117
Aquifoliaceae, 149
Aquilegia, 89
Arabia, 106
Araceae 24.
Aralia, 170
Araliaceae, 169
Arbor Vitae, 18
Arbutus, Trailing, 182
Arctostaphylos, 182
Argentina, 119
Arisaema, 25
Aristolochia, 69
Aristolochiaceae, 68
Aronia, 116
Arrowhead, 21
Arrowwood. 234
Arum Family, 24
Asarum, 68
Asclepiadacese, 194
Asclepias, 195, 196
Asclepiodora. 195
Ash, 189, 190
Ash, Mountain, 117
Asimina, 93
Asp, Quaking, 51
Asparagus, 39
Aspen, American, 51
Astragalus. 137
Atamasco Lily, 44
Atamosco, 44
Avens, 121
259
Babies’ Toes, 145
Bachelor’s Button, 249
Bald Cypress, 18
Balsam, 153, 154
Balsam Family, 153
Balsam Fir, 17
Balsaminaceae, 153
Bamboo Vine, 43
Baneberry, 90
Baptisia, 131
Barbarea, 105
Barberry, 92
Barberry Family. 91
Barren Strawberry. 119
Basswood, 158
Bastard Toadflax, 67
Batodendron, 183
Bayberry, 52
Bayberry Family, 51
Beach Pea, 139
Beaked Hazelnut, 55
Bean, 140
Bear Grass. 39
Bearberry, 182
Bedstraw, 228
Beech. 59
Beech Family, 58
Beggar’s Lice, 204
Begonia, 104-166
Begonia Family, 164
Begoniaceae, 164
Bell Flower, 238
Beilis. 242
Bellwort. 34
Benjamin, 42
Benzoin, 95
Berberidaceae, 91
Berberis. 92
Berchemia. 1-54
Betula, 56260
KEY AND FLORA
Betulaceae, 54
Bicuculla, 98
Bignonia, 223
Bignonia Family, 222
Bignoniaeese, 222
Bindweed, 199
Bircli, 56, 57
Birch Family, 54
Bird’s Pepper, 102
Bishop’s Cap, 111
Bitter Cress, 106
Bittersweet, 150, 214
Black Alder, 149
Black Gum, 177
Black Haw, 234
Black Locust, 137
Black Walnut, 53
Bladder Nut, 151
Bladder Nut Family, 151
Blackberry, 122, 123
Bladder Pod, 102
Bleeding Heart, 99
Bloodroot, 96
Blue Beech, 56
Blue Cohosh, 91
Blue Dandelion, 250
Blue Devils, 207
Blue Flag, 45, 47
Blue Sailors, 250
Blue Thistle, 207
Blue Valerian, 201
Bluebell, 201, 205
Blueberry, 183, 184
Blue-Eyed Grass, 47
Bluets, 229, 230
Blueweed, 207
Borage Family, 203
Boraginacese, 203
Boston Ivy, 156
Bouvardia, 229
Box Elder, 152
Bradleya, 137
Brassica, 103
Breeches Flower, 99
Bridal Wreath, 115
Brooklime, 220
Broom Rape Family, 223
Broussonetia, 65
Buck Bean, 192
Buckeye, 153
Buckeye Family, 152
Buckthorn, 155
Buckthorn Family, 154
Buckwheat, 72
Buckwheat Family, 69
Buffalo Apple, 138
Buffalo Bur, 215
Buffalo Pea, 139
Bull Nut, 53
Bull’s-Eye, 247
Bulrush, 24
Bunchberry, 176
Bur, Sand, 215
Bursa, 103
Butneria, 94
Butter and Eggs, 218
Buttercup, 84, 85
Buttercup Family, 83
Butterfly Weed, 195, 196
Butternut, 53
Butterweed, 243
Button Snakeroot, 171
Buttonwood, 113
Cactacese, 166
Cactus, 166. 107
Cactus Family, 166
Calamus, 26
Calico Bush, 181
Callicarpa, 208
Callirhoe, 159
Caltha, 88
Calycanthacete, 94
Calycanthus, 94
Calycanthus Family, 94
Camassia, 38
Campanula, 238
Campanula Family, 237
Campanulace®, 237
Cancer Root, 224
Cannabis, 66
Cantaloupe, 237
Caper Family, 107
Capnoides, 99
Capparidacete, 107
Caprifoliacete, 230
Capsella, 103
Caraway, 173
Cardamine, 106
Card a us, 248
Carnation, 81
Carpenter Weed, 211
Carpet Weed, 76
Carpinus, 55
Carrion Flower, 43
Carrot, 175
Carum, 173
Carya, 53
Caryophyllacese, 77
Castalia, 82
Castanea, 59
Castilleja, 221
Catalpa, 222, 223
Cat-Brier, 43
Catchfly, 80
Catnip, 211
Cat-Tail, 20
Cat-Tail Family, 20
Caulophyllum, 91
Ceanothus, 155
Cedar, 18
Celandine, 97
Celastracete, 150
Celastrus, 150
Celtis, 64
Centaurea, 249
Centunculus. 188
Cerastium, 78
Cercis, 130
Cereus, 167
Chaffweed, 188
Chamfelirium, 32
Charlock, 103, 104
Cheeses, 159
Chelidonimn, 97
Chenopodiacete, 72
Chenopodium, 73
Cherry, 124, 125
Chestnut, 59
Chicktveed, 78, 79
Chickweed Wintergreen,
187
Chicory, 250
Chimaphila, 178
Chinese Sacred Lily, 44
Chinquapin, 59
Chinquapin, Water, 83
Chionanthus, 191
Chocolate Root, 121
Choke Pear, 117INDEX
261
Chokeberry, 117
Chokeckerry, 125
Chrosperrna, 33
Chrysanthemum, 247
Cichorium, 249
Cinquefoil, 119, 120
Circaea, 169
Cirsium, 248
Citrullus, 237	_
Citrus, 144
Cladrastis, 131
Claytonia, 76
Clematis, 88
Cleome, 107
Clove Pink, 81
Clover, 133, 134
Coffee Tree, 130
Cohosh, 91
Columbine, 89
Comandra, 67
Comfrey, 204
Commelina, 27
Commelinacese, 26
Composite, 239
Composite Family, 239
Cone Flower, 244
Conopholis, 223
Convallaria, 41
Convolvulacete, 197
Convolvulus, 199
Convolvulus Family,
197
Coptis, 89
Coreopsis, 245
Corn Cockle, 79
Corn Grom well, 206
Corn Salad, 236
Cornace*. 175
Cornel, 176
Cornus, 176
Corydalis, 99
Corylus, 54
Cottonwood, 51
Cow Lily, 82
Cow Parsnip, 175
Cowslip, 88
Crab Apple, 117
Cranberry, 184
Cranberry Tree, 234
Cranesbill, 141
Crattegus, 118
Creepers, 199
Creeping Charley, 211
Cress, 102, 105, 106
Crinkle Root, 106
Crocus, 45
Cross Vine, 223
Crow Victuals, 211
Crowfoot, 84
Crown Imperial, 37
Crown of Thorns, 147
Crow’s-Foot, 106
Cruciferse, 99
Cucumber, 237
Cucumber Tree, 93
Cucumis, 237
Cucurbita, 236
Cucurbitaceae, 236
Currant, 112
Cydonia, 116
Cynoglossum, 204
Cyperaceae, 23
Cypress, 18
Cypress Spurge, 148
Cypress Vine, 198
Cypripedium, 48
Cytisus, 133
Daffodil, 44
Daffy, 44
Daisy, 242
Dakota Turnip, 136
Dandelion, 251
Dangleberry, 182
Datura, 216
Daucus, 175
Day Lily, 36
Dayflower, Virginia, 28
Dead Nettle, 212
Deerberry, 183
Delphinium, 89
Dentaria, 105
Deptford Pink, 81
Desmanthus, 129
Desmodium, 138
Deutzia, 111
Devil’s Bit, 33
Dewberry, 123
Dianthera, 224
Dianthus, 81
Dicentra, 98
Diervilla, 230
Diospyros, 189
Dock, 70
Dodecatheon, 188
Dog Bur, 204
Dog Fennel, 247
Dogbane, 194
Dogbane Family, 192
Dogberry, 117
Dog-Brier, 43
Dogtooth Violet, 37
Dogwood, 176, 177
Dogwood, Poison, 148
Dogwood Family, 175
Dragon Root, 25
Dutchman’s Breeches, 99
Dutchman’s Pipe, 69
Dutchman’s Pipe Family,
68
Ear Drops, 99
Easter Flower, 44
Ebenacese, 188
Ebony Family, 188
Echinocystis, 237
Echium, 207
Elder, 235
Ellisia, 202
Elm, 62-64
Elm Family, 62
Enchanter’s Nightshade,
169
English Ivy, 170
English Walnut, 53
Epigtea, 182
Ericaceae, 179
Erigenia, 172
Erigeron, 242
Eryngium, 171
Erythronium, 37
Eschscholtzia, 96
Euphorbia, 146-148
Euphorbiacese, 145
Eutoca, 203
Evening Primrose, 168
Evening Primrose Fam-
ily, 168
Evonymus, 150
Eyebright, 229262
Fagacese, 58
Fagopyrum, 72
Fagus, 59
Fairy Cup, 111
False Buckwheat, 72
False Dandelion, 253
False Indigo, 136
False Miterwort, 110
False Spikenard, 40
Farkleberry, 183
Feverwort, 233
Field Cress, 102
Figwort Family, 217
Filipendula, 120
Fir, 17
Fire Pink, 81
Flag, 26, 45-47
Flax, 143
Flax Family, 143
Fleabane, 243
Fleur-de-Lis, 47
Flowering Maple, 158
Flowering Moss, 201
Fly Poison, 33
Forget-Me-Not, 205
Forsythia, 190
Fragaria, 118
Fraxinus, 189
French Mulberry, 209
Fringe Cup, 111
Fringe Tree, 191
Fritillaria, 36
Fuchsia, 169
Galium, 227
Garget Root, 76
Garlic, 35
Gaylussacia, 182
Gentian Family, 191
Gentianacese, 191
Geraniacese, 140
Geranium, 140. 141
Geranium Family, 140
Geum, 121
Gill-over-the-Ground, 211
Gillyflower, 102
Ginseng Family, 169
Gleditsia, 130
Gold Thread. 89
Golden Alexanders, 174
KEY AND FLORA
Golden Chain, 133
Goose Grass, 228
Gooseberry, 112
Goosefoot, 73
Goosefoot Family, 72
Gourd Family, 236
Graminese, 22
Grape, 156, 157
Grape Family, 155
Grass Family, 22
Grass Pink, 81
Gratiola, 219
Graveyard Moss, 148
Green-Brier, 43
Green Dragon, 25
Gromwell, Corn, 206
Ground Ivy, 211
Ground Pink, 201
Ground Plum, 138
Guinea-Hen Flower, 37
Gum, Black, 177
Gymnocladus, 129
Gymnosperms, 13-19
Gypsy Weed, 220
Hackberry, 64
Hackmatack, 18
Harbinger of Spring, 172
Hardback, 115
Harebell, 238
Hartmannia, 168
Haw, 234
Hazelnut, 55, 56
Healall, 211
Heath Family, 179
Hedge Mustard, 104
Helenium, 246
Heliotrope, 204
Heliotropium, 203
Hellebore, White, 33
Hemerocallis, 35
Hemlock, 17
Hemp, 66
Henbit, 212
Hepatica, 86
Heracleum, 175
Herb Robert, 141
Heuchera, 110
Hickory, 53
Hicoria, 53
Hieracium, 253
High-Bush Cranberry,
234
Hippocastanacese, 152
Hobblebush, 233
Holly, 149
Holly Family, 149
Honey Locust, 130
Honeysuckle, 180, 230-
232
HoneysuckleFamily, 230
Hop Clover, 134
Hop Tree, 144
Horehound, 210
Hornbeam, 56
Horse Gentian, 233
Horse Nettle, 215
Horse-Brier, 43
Horse-Chestnut, 153
Horse-Radish, 105
Hound’s-Tongue, 204
Houstonia, 229
Hoya, 197
Huckleberry, 182
Hyacinth, 38
Hyacinthus, 38
Hydrophyllaceae, 201
Ilydrophyllum, 202
Ilypericaceae, 160
Hypericum, 160
Hypopitys, 179
Hypoxis, 44
Ice Plant, 76
Ice Plant Family, 76
Ilex, 149
Impatiens, 153
Indian Chief, 188
Indian Cress Family, 142
Indian Hemp, 194
Indian Paint, 206
Indian Pink, 221
Indian Pipe, 179
Indian Poke, 33
Indian Turnip, 25
Indigo, 131
Indigo, False, 136
Innocence, 229
Ipomoea, 198
Iridacete, 45Iris, 45
Iris Family, 45
Irish Potato, 215
Ironwood, 55
Isopyrum, 88
Ivy, 156
Jaek-in-the-Pulpit, 25
Jacob’s Ladder, 201
Japanese Ivy, 156
Jatropha, 146
Jerusalem Oak, 73
Jewelweed, 154
Jimson Weed, 216
Jointed Charlock, 103
Juglandacete, 52
Juglans, 52
Juncacese, 30
Juneberry, 118
Juniper, 19
Juniperus, 19
Kalmia, 181
Kicking Colt, 154
King Nut, 53
Kinnikinnik, 176
Kneiffia, 108
Knotgrass, 71
Koniga, 101
Krigia, 250
Labiatse, 209
Laburnum, 132, 133
Lactuca, 252
Lady’s Slipper, 153,
154
Lady’s Thumb, 71
Lady’s Tresses, 48
Lagenaria, 237
Lamb Lettuce, 236
Lamb’s Quarters, 73
Lambkill, 181
Lam in m, 211
Lappula, 204
Larch, 18
Larix, 17
Larkspur, 90
Lathyrus, 139
Lauraceee, 95
Laurel, 181, 182
INDEX
Laurel Family, 95
Lead Plant, 136
Leather Flower, 88
Leguminosse, 126
Lemon, 144
Leontodon, 250
Leonurus, 212
Lepidium, 102
Leptilon, 242
Lesquerella, 102
Lettuce, 252
Leverwood, 55
Ligustrum, 191
Lilac, 190, 191
Liliacete, 30
Lilium, 36
Lily, 36
Lily Family,r30
Lily of the Valley, 41
Lime, 158
Linaceae, 143
Linaria, 218
Linden, 158
Linden Family, 157
Linn tea, 232
Linum, 143
Liriodendron, 93
Lithospermurn, 200
Liver Berry, 40
Liverleaf, 86
Liverwort, 86
Lobularia, 101
Locust, 137
Lomatium, 174
London Pride, 80
Lonieera, 231
Loosestrife, 186, 187
Lorantbacese, 68
Lotus, 83
Lousewort, 221
Lungwort, 205
Lupinus, 132
Lychnis, 79
Lycium, 215
Lycopersicum, 215
Lyonia, 181
Lysimachia, 186
Maclura, 65
Macrocalyx, 202
263
Madder Family, 227
Magnolia, 92
Magnolia Family, 92
Magnoliacese, 92
Maianthemum, 40
Male Berry, 181
Mallow, 159
Mallow Family, 158
Malus, 116
Malva, 159
Malvaceae, 158
Malvastrum, 159
Maple, 151, 152
Maple Family, 151
Marguerite, 247
Marigold, Marsh, 88
Marrubium, 210
Marsh Bellflower, 238
Marsh Marigold, 88
Marsh Trefoil, 192
Matrimony Vine, 216
Matthiola, 102
May Apple, 91
May Wings, 145
Mayflower, 110, 182
Mayweed, 247
Meadow Parsnip, 174
Meadow Rue, 86
Meadowsweet, 120
Medicago, 135
Medick, 135
Megapterium, 168
Meibomia, 138
Melilotus, 134
Melon, 237
Menyanthes, 192
Mercury, 149
Mertensia, 205
Mignonette, 108
Mignonette Family, 108
Milkweed, 196, 197
Milkweed Family, 194
Mint Family, 209
Mistletoe, 68
Mistletoe Family, 68
Mitchella, 228
Mitella, 111
Miterwort, 110
Mollugo, 76
Moneywort, 186264
KEY AND FLORA
Monkshood, 90
Monotropa, 179
Moracese, 64
Morning-Glory, 198
Morning-Glory Family,
197
Morongia, 129
Morns, 64
Moss Pink, 201
Motherwort, 212
Mountain Ash. 117
Mountain Fringe, 98
Mouse-Ear Chickweed,
79
Mulberry, 65
Mulberry, French, 209
Mulberry, Mexican, 209
Mulberry Family, 64
Mullein, Moth, 217
Mullein Pink, 79
Muskmelon, 237
Mustard, 104
Mustard Family, 99
Myosotis, 205
Myriea, 51
Myricace®, 51
Narcissus, 44
Nasturtium, 143
Nelumbo, 83
Nepeta, 211
Nerium, 194
Nettle, 67
Nettle Family, 66
New Jersey Tea, 155
Nightshade, 214
Nightshade Family, 214
Ninebark, 115
Noble Liverwort, 86
None-so-Pretty, 80
Nonesuch, 135
Nothocalais, 252
Nothoscordurn, 35
Nutmeg Melon, 237
Nymphsea, 82
Nymphseace®, 82
Nyssa, 177
Oak, 60-62
Oakesia, 34
Obolaria, 192
CEnothera, 168
Oleace®, 189
Oleander, 194
Olive Family, 189
Onagra, 168
Onagrace®, 168
Onion, 35
Onosmodium, 206
Opulaster, 115
Opuntia, 166
Orange, 144
Orange, Osage, 65
Orange Grass, 160
Orchidace®, 47
Orchis Family, 47
Ornithogalum, 38
Orobanchace®, 223
Osage Orange, 65
Osmorhiza, 173
Ostrya, 55
Oxalidace®, 142
Oxalis, 142
Oxy coccus, 183
P®onia, 89
Paint Brush, 221, 253
Painted Cup, 221
Pansy, 163
Papaver, 97
Papaverace®, 96
Papaw,94
Papaw Family, 93
Paper Mulberry, 66
l’appoose Root, 91
Parsley, 174
Parsley Family, 170
Parsnip, 175
Parthenocissus, 156
Partridge Berry, 229
Pasque Flower, 87
Passiflora, 164
Passiflorace®, 163
Passion Flower, 164
Passion Flower Family,
163
Pastinaca, 175
Pea, 139, 140
Pea Family, 126
Peach,126
Pear, 116
Pecan, 53
Pedicularis, 221
Pelargonium, 141
Pennywort, 192
Pentstemon, 219
Peony, 89
Pepper Root, 106
Pepper-and-Salt, 172
Peppergrass, 102
Periwinkle, 193
Persimmon, 189	"
Petunia, 217
Phacelia, 203
Phaseolus, 140
Philadelphus, 111
Phlox, 200, 201
Phlox Family, 199
Phoradendron, 68
Phyllocactus, 167
Physocarpus, 115
Phytolacca, 75
Phytolaccace®, 75
Picea, 16
Pickerel Weed, 30
Pickerel-Weed Family,
28
Pieris, 181
Pignut, 54
Pigtveed, 73, 75
Pimpernel, 188
Pine, 14
Pine Family, 13
Pinesap, 179
Pineweed, 160
Pink, 81, 180
Pink Family, 77
Pinus, 14
Pipe Vine, 69
Pipsissewa, 178
Pisum, 139
Pitcher Plant Family,
108
Plantaginace®, 225
Plantago, 226
Plantain, 226
Plantain, Water, 22
Plantain Family, 225
Platanacefe, 113
Platanus, 113INDEX
265
Pleurisy Root, 195
Plum, 125
Podophyllum, 91
Poet’s Narcissus, 44
Poison Dogwood, 148
Poison Ivy, 149
Poison Vine, 149
Poke, Indian, 33
Pokeweed, 75
Pokeweed Family, 75
Polanisia, 107
Polemoniacese, 199
Polemonium, 201
Polycodium, 183
Poly gala, 145
Polygala Family, 145
Polygalaceae, 145
Polygonaceae, 69
Polygonatum, 40
Polygonum, 70
Pomme Blanche, 136
Pontederia, 28
Pontederiaceae, 28
Poor Man’s Weather-
glass, 188
Poplar, 50, 51, 93
Poppy, 97
Poppy Family, 96
Poppy Mallow, 159, 100
Populus, 50
l’ortulaca, 77
Portulaca Family, 76
Portulac.acese, 76
Potato, 215
Potato Vine, 198
Potentilla, 119
Prairie Apple, 138
Prairie Fire, 221
Prickly Ash, 144
Prickly Pear, 166
Primrose, 185
Primrose Family, 184
Primula, 185
Primulace®, 184
Prince’s Pine, 178
Privet, 191
Prunella, 211
Prunus, 124
Psedera, 156
Psoralea, 135
Ptelea, 144
Puccoon, 206
Pudding Berry, 176
Pulse Family, 126
Purslane, 77
Purslane Family, 76
Pyrola, 178
Pyrola Family, 177
Pyrolace®, 177
Pyrrhopappus, 253
Pyrus, 116
Quaker Ladies, 229
Quaking Asp, 51
Quamasia, 38
Quamoclit, 198
Queen of the Prairie,
120
Quercus, 60
Quince, 116
Radicula, 104
Radish, 103
Radish, Wild, 103
Ragweed, 248
Rammculacefe, 83
Ranunculus, 84
Raphanus, 103
Raspberry, 122
Ratibida, 244
Rattan Vine, 154
Rattlebox, 81
Rattlesnake Master, 171
Rattlesnake Weed, 253
Red Cedar, 19
Red Root, 155
Redbud, 130
Reseda, 108
Resedacese, 108
Rhamnacese, 154
Rhamnus, 154
Rhododendron, 180
Rhus, 148
Rib Grass, 226
Ribes, 112
Robin Runaway, 211
Robinia, 136
Robin’s Plantain, 243
Rocky Mountain Bee
Plant, 108
Roripa, 104
Rosa, 123
Rosace*, 113
Rose, 123, 124
Rose Family, 113
Rowan Tree, 117
Rubiacete, 227
Rubus, 121
Rudbeckia, 244
Rue Anemone, 86
Rue Family, 144
Ruellia, 225
Rumex, 70
Rush Family, 30
Rutacete, 144
Rutland Beauty, 199
Sage, 213
Sagittaria, 21
St. John’s-wort, 160
St. John’s-wort Family,
160
Salicaceae, 48
Salix, 48
Salomonia, 40
Salvia, 213
Sambucus, 234
Sand Bur, 215
Sandalwood Family, 67
Sanguinaria, 96
Sanicle, 172
Sanicula, 172
Santalacete, 67
Sarothra, 160
Sarracenia, 109
Sarraceniacese, 108
Sarsaparilla, 170
Sassafras, 95
Savin, 19
Saxifraga, 109
Saxifragaceae, 109
Saxifrage, 109, 110
Saxifrage Family, 109
Schrankia, 129
Scilla, 37
Scrophulariace®, 217
Scutellaria, 210
Sedge Family, 23
Self-Heal, 211
Seneca Snakeroot, 145266
KEY AND FLORA
Senecio, 247
Sensitive Brier, 129
Sensitive Rose, 129
Service Berry, 118
Shad Bush, 118
Shame Vine, 129
Sheep Lice, 204
Sheep Sorrel, 70
Shellbark, 53
Shepherd’s l’urse, 103
Sheriff Pink, 247
Shin Leaf, 178
Shoe Strings, 136
Shooting Star, 188
Shrub, 94
Sickle Pod, 107
Sicyos, 237
Sidesaddle Flower, 109
Sieversitt, 121
Silene, 80
Silverweed, 120
Sisymbrium, 104
Sisyrinchium, 47
Sitilias, 253
Skullcap, 210
Skunk Cabbage, 25
Smartweed, 71
Smilacese, 32
Smilacina, 39
Smilax, 42
Snakeroot, Black, 173
Snakeroot, Samson’s,
135
Snakeroot, Seneca, 145
Snapdragon, 218
Snappers, 81
Snapweed, 154
Sneezeweed, 246
Snow on the Mountain,
147
Snowball, 234
Snowberry, 232
Solanaceas, 214
Solanum, 214
Solomon’s Seal, 41
Sonchus, 251
Sophora, 132
Sorbus, 116
Sorrel, Sheep, 70
Spanish Dagger, 39
Spathyema, 25
Spatter-Dock, 82
Spearwort, 84
Specularia, 238
Speedwell, 220
Spice Bush, 96
Spiderwort, 27
Spiderwort Family, 26
Spikenard, False, 40
Spinach, 73
Spinacia, 73
Spirtea, 115
Spiranthes, 48
Spring Beauty, 77
Spruce, 16, 17
Spurge, 147, 148
Spurge Family, 145
Spurge Nettle, 146
Squash, 237
Squaw Vine, 229
Squawroot, 42
Squill, 37
Squirrel Corn, 99
Stachys, 212
Staggerbush, 181
Staphylea, 151
Staphyleacete, 151
Star Flower, 187
Star Grass, 45
Star of Bethlehem, 38
Steironema, 186
Stellaria, 78
Stick-Tights, 204
Stitchwort, 78
Stock, 102
Straw Lilies, 34
Strawberry, 118, 119
Strawberry Bush, 94,
150
Streptopus, 40
Sugar Pear, 118
Sumac, 148
Sumac Family, 148
Sundrops, 168
Supple Jack, 154
Sweet Alyssum, 101
Sweet Bay, 92
Sweet Cicely, 173
Sweet Clover, 135
Sweet Fern, 52
Sweet Flag, 26
Sweet Pea, 139
Sweet Potato, 198
Sweet William, 81
Sweetbrier, 124
Sweet-Scented Shrub, 94
Sycamore, 113
Sycamore Family, 113
Symphoricarpus, 232
Symplocarpus, 25
Sypdesmon, 86
Syringa, 111, 190
Tamarack, 18
Tangleberry, 182
Tansy Mustard, 104
Taraxacum, 251
Tassel Tree, 158
Taxodium, 18
Tecoma, 222
Thalesia, 224
Thalietrum, 85
Thaspium. 174
Thistle, 248, 249, 251
Thuja, 18
Thyme, 213
Thymus, 213
Tiarella, 110
Tickseed, 245, 246
Tilia, 157
Tiliacese, 157
Tinker Weed, 233
Tipsin, 130
Toadflax, 218
Toadflax, Bastard, 67
Tomato, 215
Tongue Grass, 102
Toothache Tree, 144
Toothwort, 106
Toxylon, 65
Tradescantia, 27
Trailing Arbutus, 182
Trefoil, Marsh, 192
Trientalis, 187
Trifolium, 133
Trillium, 41
Triosteum, 233
Tropteolace®, 142
Tropteolum, 143
Tropseolum Family, 142INDEX
267
Trumpet Creeper, 222
Trumpet Flower, 222
Tsuga, 17
Tulip, 37
Tulip Tree, 93
Tulipa, 37
Tumbleweed, 74
Tupelo, 177
Turkey Pea, 172
Twin Flower, 233
Two-Eye Berry, 229
Typha, 20
Typhacese, 20
Ulmaee*, 02
Ulmaria, 120
Ulmus, 62
Umbellifera?, 170
Umbrella Tree, 93
Unicorn Root, 33
Urtica, 66
Urticacete, 66
Uvular ia, 33
Vaccinium, 183
Vagner a, 39
Valerian, 235
Valerian Family, 235
Valeriana, 235
Valerianaceae, 235
Valerianella, 236
Veratrum, 33
Verbascum, 217
Verbena, 207, 208
Verbena Family, 207
Verbenacese, 207
Veronica, 220
Vervain, 208
Vetch, 139
Viburnum, 233
Vicia, 138
Vinca, 193
Vine Family, 155
Viola, 161
Violace®, 161
Violet, 161-163
Violet Family, 161
Virginia Creeper, 156
Virginia Dayflower, 28
Vitaeeae, 155
Vitis, 156
'Wafer Ash, 144
Wahoo, 150
Wait-a-Bit, 43
Wake-Robin, 42
Waldsteinia, 119
Walnut, 53
Walnut Family, 52
Wandering Jew, 28
IVashingtonia, 173
Water Chinquapin, 83
Water Lily, 82
Water Lily Family, 82
Water Pepper, 71
Water Plantain, 22
Water Plantain Family,
21
Water Willow, 225
Watercress, 105
Waterleaf Family, 201
Was Plant, 197
Waxberry, 52
Waxwork, 150
Weigela, 231
White Hellebore, 33
Whiteweed, 247
Whitewood, 93, 158
Whitlavia, 203
Wickakee, 221
Wild Coffee, 233
Wild Flax, 218
Wild Ginger, 69
Wild Hyacinth, 38
Wild Licorice, 228
Wild Lily of the Valley,
40
Wild Oats, 34
Wild Pear, 118
Wild Pink, 81
Wild Potato Vine, 198
Wild Sweet William, 200
Willow, 49, 50
Willow Family, 48
Wind Flower, 87
Winter Cress, 105
Winterberry, 149
Wintergreen, 178
Wisteria, 137
Witch Hobble, 233
Withe-Rod, 234
Wood Sorrel, 142
Wood Sorrel Family, 142
Woodbine, 156
Xanthoxylum, 144
Xolisma, 181
Yarrow, 246
Yellow Cress, 105
Yellow Flag, 47
Yellow Pond Lily, 82
Yellow Street Clover, 135
Yellow Wood, 132
Yucca, 39 •
Zebrina, 28
Zephyranthes, 44
Zizia, 173