r Digitized by tine Internet Arcliive in 2010 witli funding from Open Knowledge Commons (for the Medical Heritage Library project) http://www.archive.org/details/physiologypatholOOnorr THE PHYSIOLOGY AND PATHOLOGY OF THE BLOOD. THE PHYSIOLOGY AND PATHOLOGY OF THE BLOOD: COMPKISINCt THE OEIOIN, MODE OF DEViSLOl^MENT, PATHOLOGICAL AND POST-MOKTJCM CH.ANH1'> OF ITS MORPHOLOGICAL ELEMENTS IN MAMMALIAN AND OVIPAROUS VERTEBRATES. RICHARD NORRIS, M.D., F.R.S.E. PROFESSOP> OF PHYSIOLOGY, QUEEN's COLLEGE, BIRMINGHAM ; VICE-PRESIDENT OF THE BIRMINGHAM PHILOSOPHICAL SOCIETY. WITH MICRO-PHOTOGRAPHIC ILLUSTRATIONS. Truth is one : Error is manifold. LONDON : SMITH, ELDEE, & CO., 16. WATERLOO PLACE. 1882. [Al,l. rif/lils reaerved.] hi^ PRINTED BY WEIGHT, DAIN, PEYTON, AND CO., AT THE HEKALD PRESS, BIKMINGHAJI. ®o t)^t P^tmorji of WILLIAM HEWSON, ONE 01<- THK EARLIEST AND MOST ACUTE MICKOSCOPICAL INVESTIGATOIIS OF THE PHYSIOLOGY AND PATHOLOGY OF THE BLOOD, THIS WO 1! K |s (irakfuUg J^bttatftf BY THE AUTHOR. TABLE OF CONTENTS. Title, Dedication, etc. Contents of Sections and of Appendix, etc. . List of Micro-Photogbaphs and Illustrations Pbeface Introduction Sections Plates and Desceipt: Appendix Index Page. i-iv. v-xvi. xvii-xxi. xxii-xxxv. xxxvi-xlv. 1-198 199-230 231-255 256-274 SECTION I. on the existence in the blood of a previously unknown corpuscle which explains the origin of the red disc and the formation of fibrin. Part I. — Existence in the blood of an invisible, colourless disc — How discovered — Various methods by which it can be rendered obvious — By impact — By packing — -By altering the refractive index of the liquor sanguinis^By isolation — By osmic acid vapour and cold — By absolute alcohol and solution of osmic acid — By spreading and drying — By tinting the liquor san- guinis — By staining. . . . . . . . . . . , . 1-13 Part II. — Origin of colourless biconcave discs — Three conceptions possible: 1. May be decolourised red discs; 2. May represent a stage in the dissolution of the red disc ; 3. May be discs destined to acquire colour and to become red discs — Nature of lymphatic and splenic corpuscles — Rarely seen in their normal condition — Changes which they undergo — Enlargement, aggregation, fibrillation, spreading and lamination — Normal form not globular but discoid — Often biconcave in young animals — Biconcavity a physical property — -Comparison of the lymph and splenic corpuscles with the white blood corpuscle — Opinions as to their identity — Reasons why they cannot be regarded as identical . . . . . . . . . . . . . . 13-20 Part III. — The granule sphere of Semnier (Kcirnerkugeln) — Found in horse's plasma at ice cold temperature — Coloured and larger than white corpuscles — Behaviour with reagents — Supposed VI Conientx. by Semmer to be intermediate bodies between the ordinary Page white corpuscle and the red blood disc — Must exist therefore in perfectly fresh blood — Blood kept from coagulating by cold assumed to be fresh blood — What eif ect has cold upon the cor- puscular elements? Blood can be examined much earlier than by Semmer's method — No bodies present of the nature of granule balls — How and from what they are formed— Cause of nucleated appearance — Relations of the granule corpuscles to fibrin — Semmer's facts do not support the view that the red disc is developed from the white corpuscles — Summary of the author's views of the mode in which the red disc is developed 20-24 Part IV. — Cause of the biconcave form of the blood disc — Views of Rindfleisch — Mechanical modelling inconsistent with elasti- city — John Hunter believed the red corpuscles to be liquid bodies — Hewson held the corpuscles to be solid, on the ground that they were " flat bodies," and " because every fluid swim- ming in another, which is in larger quantity, if it be not soluble in that other fluid, becomes globular " — This reasoning deemed conclusive — Views of the cause of the biconcave form — Capsule — Rollett's skeleton framework or stroma — Thudicum's defini- tion of this so-called stroma — Insuj)erable difficulties of this conception from a physical point of view — Interpretation of its chemical aspects — The idea of a capsular membrane or a stroma unnecessary — Hunter's view of the liquid nature of the corpuscles still tenable — Liquid globules and liquid bicon- cave discs can be produced artificially — Hewson's view th at every liquid immiscible in another must necessarily be globular based upon insufiicient experimental data — Methods by which colloid globules and elastic biconcave discs can be artificially produced — General principles upon which their production appears to depend — Phenomena of osmosis ; how explained. 'JI-SGc Part V. — On fibrin formation and coagulation — Has been regarded as a physical and chemical question — Little attention paid to its microscopical aspect — The element or elements yielding fibrin supposed to be in sohttioji — In reality a morphological problem — llie younf/er or fufjitive discs of the blood undergo actual transformation into fibrinous networks, films, layers, and masses (emboli) — The colourless and slightly-coloured discs are the true fibrin stroma (numerous proofs of this in Section IV.) — What occurs when blood is kept fluid at 0° C. — Real action of solid neutral salt upon plasma — Effect of weak saline upon plasmine precipitates — Subsequent act of hardening .S(jc-36d SECTION IL FURTHER RESEARCHES ON THE THIRD CORPUSCULAR ELEMENT OF MAMMALIAN BLOOD. Advance in the physiologj', pathology, and coagulation of the blood impossible without a knowledge of this element — Review of the position — Do these colourless discs exist in normal unshed blood — All objectors now admit the existence of these colourless discs in sJied blood — Discussion hinges altogether on the point as to whether they are decolourised red discs — All the facts, without exception, are against this view^ — 1. Their presence can be demonstrated without reagents of any kind, that is by simple mechanical ai'rangements — 2. They Contents, vii ^^ can be seen immediately the blood is shed — 3. They have not Page the properties of coloured or decolourised blood discs, but of lymph corpuscles — 4. Like white corpuscles, they are adhesive to the slide and cover — 5. They uuderj^o transformation into fibrin —6. They are absent in completely defibrinated blood — 7. The better the blood is preserved, t'.//., by dry osmic acid vapour, ice-cold temperature, etc., the more perfectly they are seen — 8. They are well seen when all solution of the haemo- globin in the serum is prevented by the use of colloids — 9. They are equally well seen when the blood is purposely saturated with haemoglobin from an independent source at the moment it leaves the vessels — 10. With saline aniline blue they stain deeply and appear as full, plump bodies, while decolourised discs stain very faintly with this agent — 11. They undergo transformation into rosette and granule forms, which is not the case with decolourised red discs — 12. The slightly coloured forms of these corpuscles give rise by their disinte- grations to the so-called luematoblasts of Hayem — 13. These delicately tinted ones are visible in the circulating blood — 14. The notion that the invisible and partially coloured discs are the products of compression or violence is entirely without foundation — 15. No conditions which involve compression or violence necessary, nor can these corpuscles be intentionally pro- duced by the adoption of such methods — 16. The only condi- tion necessary is to draw the corpuscles together in single layer, but their biconcavities need not be interfered with in the slightest degree by compression — Thin flexible mica covers, about ljx§ of an inch, produce these conditions perfectly — Large numbers of disc-shaped corpuscles pass continualh into the blood from the lymphatics — These are not seen under ordmary conditions because they become the invisible colourless discs — Explanation and reply to Professor Gulliver, showing the difficulties which arise from confusing the ordinary white and the true lymph corpuscles — The bodies which Hewson saw in the blood were the ordinary white corpuscles, not the true lymph discs — Views as to the origin of the colourless discs — Modified lymph nuclei — Biconcave disc divisible into three sets or gi-oups, primary, secondary, and tertiary — Corpuscles of primary group are in the main invisible, landergo fusion, granulation, and fibril- lation when the blood is slied — Secondary group comprises corpuscles slightly more coloured than the liquor sanguinis, and therefore visible if carefully looked for — Permanent or tertiary group consists of ordinary red discs — Properties of the corpuscles of the fuyitive yroup — Relation to stains — Hayem's haematoblasts — Summary .. .. .. .. .. .. 36d-65 SECTION III. ON THE MOST SUCCESSFUL METHOD OF STAINIXG THE COHPUSCLES OF THE FUGITIVE GROUP. Difficulties connected with staining — No sharp line of demai'cation owing to the corpuscles being a graduated series — Power to' stain diminishes with assumption of haemoglobin — Invisible or colourless discs stain blue, those containing a little haemo- viii Contents. globin green — Processes divisible into wet and dry, or of stain- Page ing in or after removal from the liquor sanguinis — Power of the liquor sanguinis to oppose staining and to discharge the colour renders it necessary to use a strong staining fluid — Difficulties of strong stains — Preparation of staining fluid— Mode of use — Granulating property of this fluid when used in other ways — Effects of colloids and crystalloids — Property of cane- sugar — Best mode of using — Conditions required — Accessory arrangements— Strength of aniline blue — Dry method — Liquor sanguinis removed by the method of isolation — Impossibility of adding liquids again to dried corpuscles, even liquor san- guinis, without dissolving the red ones — Must be fixed by exposure to moist vapour of osmic acid — Blood must not be allowed to dry after isolation before being subjected to the osmic acid vapour — Two per cent, aniline blue applied for two minutes — Colour not to be washed off, but removed by capillary method — Most primary discs, although stained of a very deep blue, and now very palpable to the eye, cannot be photographed while those containing a slight amount of haemoglobin are easily photographed — This shows them to be devoid of haemoglobin — So delicate is this test that many corpuscles can be photographed which are entirely incapable -of producing visual impressions. . . . . . . 65-70 SECTION IV. AN EXAMINATION OF THE RESEARCHES OF H. HAYEM ON THE DEVELOP- MENT OF MAMMALIAN BLOOD. Title and date of Hayem's papers — Statement of his views and examination of his methods — Small elements exist which are neither red nor white corpuscles — These are the germs of the red corpuscles and maybe called hcematoblasts — Avoids discus- sing the origin of these elements — Seeks to ascertain the exact anatomical constitution of the blood at birth — The so-called haematoblasts are visible elements of the blood, and have colour — Are seen best in fresh blood — Method of observing these elements — High powers required — Very small bodies like delicate, pale red corpuscles — Grow paler by loss of haemo- globin— Change their form — Adhere to the slide and to tlie red discs — Unite with each other and form wreaths or groups — May be preserved for examination by cold (0° C.) — So preserved, show themselves as thin, discoid, biconcave, slightly coloured bodies — Osmic acid and bichloride of mercury preserve them — Full description — Bear no resemblance to white corpuscles — Present two parts or constituents — One portion exudes, is viscous, and is the cause of their adhesive- ness — Identification of these elements — Summary of the various morphological elements contained in nJied blood — Easy to identify among these the elements mistaken by Hayem for the germs of the red corpuscles — Modified and altered forms of the younger blood discs — Comparison of the general pro- perties of these elements with those of the discs of the fugitive group — The discs of this group must be followed through their transformations — Photograph 61 shows in one group the entire series of blood discs — Characters of the youngest discs — Power of retaining form in the ratio of colour — The younger (Jontent-s. ix corpuscles have a disposition to flatten and spread, hence their Page diameter is greater than the more coloured — Relative age of the corpuscles easily ascertained — So-called hsematoblasts disinte- grations of the intermediary discs — Apparent granule groups and isolated granules, what they are, and how formed — Easily seen by raising cover (isolation) — Adhering corpuscles under- going rosette and granule forms of disintegration — Rosette forms more perfect, with the use of warm stage — This change occurs in corpuscles having considerable colour — The coloured fibres arise from the coloured central parts — Portions of corpuscles behave precisely like entire ones, hence the centres of radiating fibrin are of variable size — Changes in green lus- trous corpuscles — Mode in which the rosette form is produced — Appearance of fragments or granules undergoing the rosette change — White border of rosette all but invisible in liquor sanguinis — Cause of angular distortion of the coloured centres — These centres called by Hayem " isolated angular colloid hsematoblasts " — These centres, sometimes large, being pro- duced by the fusion of several corpuscles — ^First step in formation of radiating fibres from rosette corpuscles — Power of contracting fibres to cut red discs into fragments — Converse arrangement of the corpuscular material to that in rosette — Younger blood discs have two constituents — Coloured material external, and masks the colourless — Probable cause of this — Corpuscles colour throughout their mass before they become strongly tinted — Analogy to zooid and oekoid — What becomes of white interior part when the corpuscles disintegrate — Both materials concerned in fibrin formation — These materials are chemically different, as shown by staining — Corpuscles coloured throughout may become wholly resolved into fibrin — Corpuscles partially exhausted by the pulling out of fibres have been styled hsematoblasts — Coagulation preceded by physical changes in the young corpuscles — The colourless discs yield white fibrin and the intermediate corpuscles the slightly coloured — Groups of corpuscles may lose their exterior coloured part and become white masses — The two modes of disintegration — passes often fuse into sheets — Granule form of dis'integration — All the corpuscles of the fugitive group can undergo this change — These groups of granules have been mistaken for adhering hsematoblasts — Corpuscles often seen in ' the act of breaking up — These form the circlets, chaplets, and beaded rolls of M. Hayem — Fragmentary parts of discs often biconcave in form — The cutting up of corpuscles by fibrin threads a source of so-called hsematoblasts — All granules and fragments of the fugitive group of discs extensible into fibres — Ordinary white corpuscles undergo granulation, but their granules are easily distinguished from those of the colourless discs, never form fibrin threads — So-called hsemato- blasts entirely accidental and extravascular formations — Methods of preventing their formation — Temperature — Osmic acid, cane-sugar — Blood subjected to ice-cold temperature not to be regarded as fresh blood — Cold causes discs to granulate — Normal temperature gives fewer fragments — Cold prevents coagulation by suspending adhesiveness and viscidity and therefore fibrillation — Effects of osmic acid — No preservative equal to white sugar — Renders the corpuscles non-adhesive — Manner of using the sugar important — Effects of different proportions of sugar — When added in sufficient quantity the X ('u7itents. formation of the granules and fragments which are called Page hseniatoblasts is entirely prevented — Due to the preservation of the corpuscles of the fufjitive firoup — Contrast of M. Hayeni"s and the author's views of the development of mammalian blood . . . . . . . . . . . . . . 70-99 SECTION V. ox THE MOKPHOLOGIC.iL PRODUCTS OF THE BLOOD GLANDS. Essential to reinvestigate the products of the blood-glands — This question has received comparatively little attention — No important advance since Hewson — Lymph corpuscles still regarded as identical with the white blood corpuscle — This view is opposed by an eminent minority — Opinions of Gulliver, Gray, Bennett, and Virchow — Virchow believes some of the gland elements develop into white blood corpuscles — Offers no opinion as to the origin of the red corpuscles, but leans to the view of Hewson — No further light thrown on this point bj' modern investigators — Confusion of the products of the blood- glands and the white corpuscles of the blood erroneous and perplexing — White blood corpuscles not even identical with each other — Certain white corpuscles have a close affinitj' to the products of the blood-glands — Uninuclear cells and free nuclei alone found in the blood-glands — These two kinds may be advantageously designated the primary and advanced lymph corpuscles — Between these extreme kinds all intermediate developments maybe found — Lymph corpuscles not one body but a graduated series — Most advanced corpuscles approximate closely to the invisible or colourless discs of the blood — State in which the advanced lymph discs usually present themseh'es for examination — Description of the primary lymph corpuscle — Different manner in which the primary and advanced lymph discs photograph — This pigment not to be confounded with haemoglobin — Tendency of advanced lymph coi-puscles to extend or spread — Spreading action can be restrained by salt and the corpuscular character be better preserved— Intermediate lymph discs well seen in thyroid of calf — Power of cane-sugar to preserve advanced lymph corpuscles — The lyinph discs become unstable in the ratio of their development — The more advanced the more susceptible to swelling and staining — Action of saline aniline blue on the most advanced lymph discs— Primary lymph corpuscles neither stain nor swell, but become contracted and distorted — Proportions of the two kinds vary in different glands — Iiitermediate lymph discs also distinguishable by the extent to which they swell and stain — Advanced lymph discs often detectable only by the graimles which adhere to them — Power of the ice-cold temperature to preserve the advanced lymph discs — Method of determining the source of the granules present — Saline aniline blue distinguishes the primary, advanced, and intermediate lymph discs from each other — Lymph corpuscles are structures undergoing continuous development which involves physical and chemical change — Reason they are so difficult to study — Advanced lymph disc the source of fibrin in lymph as the younger blood discs are in blood — To study the advanced lymph disc we must prevent it falling into fibrin — Eeason why the development of the red disc has been enshrouded in mystery — Mischief of confounding the various colourless elements — The colourless elements which Contents xi give rise to red discs — Accidents or postpoiied issues — Review Page of preceding inductions —Description of primary and advanced lymph disc — Nature of the development which the lymph corpuscles undergo — Advanced lymph discs the freed and developed nuclei— Definitions of the primary and advanced lymph corpuscles — Protean forms under which the advanced lymph disc presents itself — Method of demonstrating by osmosis the cellular character of the primary lymph corpuscle — Cell-wall of primary corpuscle probably undergoes gradual solution — No cell-wall can be made to show itself by osmosis in the case of the advanced lymph disc . . . . . . . . 99-119 SECTION VI. ON THE OKIGIX, DEVELOPMENT, AND DESTINY OF THE WHITE BLOOD CORPUSCLE. Comparison of the primary and advanced lymph corpuscles with the white blood corpuscles — Varieties of white blood corpuscles — Examples and descriptions of white blood corpuscles — Uninuclear give rise to multinuclear kind — Varying states of the protoplasm of the white corpuscle — Possesses a delicate capsule — Liquid content matter sometimes escapes — View of an intercellular network erroneous — An artificial production — Primary lymph cell the antecedent of the uninuclear white corpuscle —Photographs showing the cell-wall of the white corpuscle — Primary lymph corpuscle convertible into uninu- clear white corpuscle — White blood corpuscle can be made to take on the character of primary lymph corpuscle — Origin and meaning of the white blood corpuscle — Probable destiny of the multinuclear white corpuscle — Two processes or modes in which colourless and therefore red discs are produced — Major mode from i'reed nuclei of primary lymph corpuscles — Minor from freed nuclei of multinuclear white corpuscles . . 119-124 SECTION VII. ON THE IDENTIFICATION OF THE ADVANCED LY3IPH DISC WITH THE COLOUELESS DISC OF THE BLOOD. The kind of development which the lymph corpuscles undergo — General appearance of the primary lymph disc — Assimilation in size and form to red discs — Sometimes exhibit a tendency to biconcavity — Very difficult to obtain the advanced lymph discs in their normal shape — ^Caue-sugar best preservative yet discovered — Peculiar action of saline aniline blue on the advanced lymph discs — Corpuscles in the blood which swell and stain precisely like the advanced lymph discs — Stages between these and the red discs can be shown — Saline aniline blue enables us to bridge the gap chemically between the advanced lymph disc and the colourless disc of the blood — Begions where we may expect to find the advanced lymph disc in its most developed state — When introduced into liquor sanguinis the advanced lymph disc becomes the colourless disc of the blood — General correctness of the view of Bennett — Erroneous as to the assumption of colour in the lungs — Real cause of the colourless discs not being seen — Position that the i Contents. red discs are derived from the advanced lymph discs im- Page pregnable — Colourless discs acquire colour while circulating — Probable source of this colouring inatter — Colourless discs of foetal blood approximate very closely to advanced lymph cor- puscles — Lymph aud colourless blood discs alike in their extreme mutability — Recourse to preservatives necessary with them both — Other points of similarity between the lymph and the colourless blood disc — Common source of both tlu' red and ^A\e ^Yxite corpvi^cle the primary lymfh cell .. .. . . lli-Vdl SECTION VIII. ON THE ROLE OF THE EED BONE-MARROW IN THE FORMATION OF BLOOD. Chief products of the red marrow colourless nucleated cells- Coloured nucleated forms supposed to be intermediate between the colourless and the red disc — Neumann considers the nuclei of coloured cells to undergo atrophy and absorption — The coloured cell body becomes the red disc — Transition of the colourless into the coloured cell disputed, also the conver- sion of the latter into the red disc — Eiudfleisch has failed to trace the red nucleated cells back to the colourless cells — Holds the red nucleated cells to increase by subdivision — Pro- poses for them the designation luematohlasts — Considers that their nuclei escape, and that the red protoplasm becomes modelled into the red disc — Has rarely seen the escape of the nucleus in the adult — Attributes this to the paucity of such corpuscles, and the area over which they are spread — Five natural divisions of the study — Each form of marrow requires independent examination — Variations in the blood corpuscles of the embryo at different periods — Relation of the marrow of the mammal embiyo to its blood — Colourless and intermediate nucleated cells of all shades of colour to full red in embryo blood — Origin of the clear bordered colourless cell from the analogue of the primary lymph cell of the adult mammal — These clear bordered nucleated cells acquire their colour in the blood — Same corpuscles found in the colon rlenti stak' in the embryo spleen — Numerous red discs and discs of every inter- mediate tint, including colourless discs (invisible corpuscles), in embryo blood — Comparison of blood from the aorta and the marrow of the rib of the savie embryo — What are the con- stituents proper to the bone-marrow ? — Must deduct bodies which are derived from the blood — Elements to be accounted for in the embryo blood — Source of the coloui'less nucleated corpuscles and the colourless discs of embryo blood — Ante- cedents of these bodies found readily in the spleen and lymphatics — Corpuscular constituents common to the embryo marrow and blood — Reason why coloui'ed nucleated cells cannot be regarded as blood contaminations of the marrow — If the red nucleated cells of the marrow of adult guinea-pig do not pass into the blood, neither do the cells of the marrow which are their antecedents — As red nucleated cells are plenti- ful in the marrow of the adult guinea-pig it should be easy to trace here their transformation into red discs — This process in guinea-pig a persistence of the embryonic method — Second mode of blood formation in the embryo marrow — Coiiverm'nn of eolourlesa nuclear discs into red discs — Colourless cells of the embryo marrow — Smooth pigment cells — Coarsely granular Contents. xiii '■U pigment cells — Freed nucleolated nuclei-Free, smooth nucleolus Page in marrow of advanced embryo — Pigmentary character of the primary lymph cells of the glands — What becomes of this pigment? — Original marrow corpuscle a typical ceZ/- -Changes which fit this cell to become a blood corpuscle are regressive in their character — Probable function of the pigment — How obtained in the case of the spleen and gland corpuscles — All transition stages traceable in the adult guinea-pig from the smooth, typical pigment cell to the red nucleated cell — Mode of transformation of the red nucleated cell into the red disc — Views of Rindfleisch as to the mode of transformation — Recent views of Malassez (vide Introduction) — Cells which become coloured are of very variable size — Corpuscles which adhere to each other and to the red corpuscles, and look like coloured nuclei — Blood formation from colourless discs also present . . 1:>1-143 ■ON THE EELATION OF THE MAEKOW OF THE ADULT MAMMAL TO ITS BLOOD. ■General function ascribed to the marrow — Use of the term hsemato- blast by Rindfleisch and Hayem — Formation of red discs from red nucleated cells is the only idea yet broached as to the blood-forming function of the marrow — Origination of this view — Are red nucleated cells a constituent of all bone- marrows, and, if so, do they exist in numbers sufficient to exert any important influence in corpuscle formation — Formed throughout life in guinea-pig, rabbit, etc. — In higher mammals, appear to be aborted and scant products — Ought in all mam- mals to bear a definite relation to the number of red discs produced — Their production througl|out life in the lower mammals an exceptional' fact — Process not absolutely sup- pressed in young of higher mammals — Is an embryonic mode, which gives place to the method of the glands and spleen — Marrow of adult higher mammal consists of colourless cells and free nuclei, with here and there an aborted coloured cell- All the cells found in the adult which exist in the embryo marrow, except the red nucleated ones — The function of these colourless cells is the development and liberation of nuclei — All the diversified products of the marrow have a common origin — Like the spleen and lymphatics the adult bone-marrow pro- duces colourless nuclear discs — Method of displaying these free nuclei — Two methods by which red discs are produced in the mammal: 1, From red nucleated cells; 2, from colourless naked nuclei — First or embryonic method retains its hold longer in the marrow than in the blood — Marrow of lower mam- mals yields naked nuclei to the blood — Spleen and lymphatics of embryo yield to its blood two kinds of colourless elements — The tendency is to complete uniformity of method — Admis- sion of Rindfleisch — General conclusions .. .. ..143-149 SECTION IX. NATURE OF LEUKH^EMIA. Discovered by Bennett and Virchow — Virchow first associated the condition with enlargement of spleen and glands — Red discs diminish proportionately with increase of white corpuscles — This fact has never been explained — Condition of spleen and V Contents. glands one of simple hypertrophj' — This should merely give Page rise to increase of the normal gland products — These are not white corpuscles, but pi'imary and advanced lymph discs — In perfect health a minimiim number of privmri/ lymph cor- piiscles pass from the blood glands and few white blood cor- puscles are formed — Products which leave the blood-glands mainly freed and developed nuclei — Blood-glands, not simple sites for cell production, but delay stations to afford time for the conversion of primary into advanced lymph corpuscles — Primary cells probably produced in the central portions of the pulp — Mere hyperplasia not competent alone to produce leukhaemia — Process of cell-formation intermittent — Period of quiescence devoted to cell modification — Process of cell-fonxia- tion continuous in lenkhsemia — Cells I'emain a shorter period in the glands — Fail to undergo conversion into free nuclei, pursue a cellular development, and appear in the blood as white corpuscles — Primary lymph corpuscle may either undergo conversion into a coloitrle.is disc or a irhite corpuscle — Essential fact of leukhsemia — A slow method of blood- making takes the place of a rapid one — True function of blood-glands to produce advanced lymph corpuscles or colourless discs — Leukhsemia reverses the normal order in producing white corpuscles and is an encroachment of the minor on the major process of blood-maKing — Forms of leukhsemia — How distinguishable — Many imperfectly elaborated free nuclei pass over — Saline aniline blue enables us to define the condi- tion present — Pseudo-leukhsemic products — Embolic states, etc 149-155 SECTION X. ON THE NATURE OF AN/EMIA. Conditions to which the term is applied — Broad division into hsemorrhagic and disease induced — Distinction between the two — Essential feature of anaemia arising from disease — New conceptions of anaemia rendered possible by present research — Points which specially bear upon the subject — Amount of fibrin in blood an indication of the activity of the lymphoid organs — Disproportionate decrease between red discs and haemoglobin the main fact to be accounted for in anaemia — Conditions necessary for the maintenance of the numerical status of the blood discs — Conceptions possible as to the cause of the numerical decrease of the red discs — Impossible to explain typical forms of anaemia on the view that the discs contain equal amounts of hfemoglobin — Reduction of cor- puscles in hasmoglobin follows a definite law which involves a peculiar mode of distribution of the haemoglobin — Mode in which the discs acquire haemoglobin, that of equal increments in equal times — The amount of haemoglobin will depend upon the length of time that the corpuscles are in the blood — Illus- tration of the mode in which hoDmoglobin is disposed among the corpuscles — Meaning of the terms group-figure and incre- ment number — Definition of a group — Relation of group- , Cuntents. xv figure to the average hsemoglobin increments per corpuscle — Page Definition of a set — Lymph discs enter the blood in batches — The influence of this on the distribution of the haemoglobin — Probable age of fulh^ developed blood discs — Nature of the changes which result in anemia — Explanation of Table A — Mode of applying this table to illustrate anaemic conditions — Principal object of Table A to show that a decrease in the number of corpuscles involves a disproportionate decrease in the hsemoglobin in the ratio of 2 to 3 — Condition invariably present in anaemia — Table A shows typical form of anasmia which results from diminution of corpuscles by premature death — Consideration of anaemias which deviate from the typical variety — The general cause of anaemia — Tables A and B both show effects of premature death of corpuscles — Group- figure gives the life-period of corpuscles, and from this all the other facts are ascertainable — Probable explanation of essen- tial anaemia — Malassez's observations on fowls — The cor- puscle, the haemoglobin-producing organ — Keduction of its vitality may involve three variations of function — Indepen- dence of the several powers of the corpuscles — These modified singly or together are competent to explain all the varieties of anaemia — Defects of corpuscle counting — Value of ordinary analysis — How to obtain the group-figure by analysis — Con- struction of Table B — Analysis gives a slightly higher group- figure and increment average — Perfecting of enumeration methods — Analysis of various cases of ansemia, ^nd applica- tion to them of the foregoing principles — Percentage method of estimating corpuscles and haemoglobin (Cowers) Mode of throwing these estimations into the groupal form — Table C gives percentage number for each group-figure — Relation of Table C to Table A— Eelation of Table D to Table A— Method of using these tables to interpret cases of anaemia — -Con- clusions . . . . . . . . . . . . . . . . 155-182 SECTION XI. ON THE EELATION WHICH THE PRODUCTS OF THE BONE-MAKROW AND OF THE SPLEEN OF THE ADULT OVIPARA BEAR TO ITS BLOOD. Red corpuscles of ovipara arise in part from a colourless nucleated ellipsoid — Methods by which the margins of this cell may be displayed — Intermediately coloured cells — The colourless ellipsoids are formed in the bone-marrow and spleen — These bodies are the analogue of the advanced, splenic, and bone- marrow corpuscles, and therefore of the invisible discs of the mammal — Difficult to trace these bodies, owing to the deli- cacy of their exterior margins — Origin of these bodies — Photographs and descriptions of the products of the oviparous bone-marrow and spleen — The production of these colourless ellipsoids constitutes the major process of blood-making in ovipara — Method of development in the blood from white corpuscle — Various stages of the process — Distinct from former method — In one stage these bodies are the so-called haematoblasts of Hayem — This is the minor process of blood- making in the ovipara — Observations of M. Pouchet — Com- parison of the views of M. Pouchet with those of the Author 182-190 ContenU. SECTION XII. ■ON THE ANALOGY AND RELATION WHICH SUBSIST BETWEEN THE DEVELOPMENT OF MAMMALIAN AND OVIPAROUS BLOOD. Two processes of blood-making in the adult mammal, viz., the Page production of colourless nuclear discs from the primary lymph disc, and from the white corpuscles — The former, the process carried on in the blood-glands and bone-marrow, the latter in the blood itself — Two processes of blood-making also in the adult ovipara, viz., the production of colourless nucleated ellipsoids from the spleen, lymphatics, and bone-marrow, and also from the white corpuscle in the blood itself — Bodies liberated in the latter case, not simple nuclei, but nucleolated nuclei — The growth and development of these occurs in the blood — These bodies at a certain stage of growth and colour are the hsematoblasts of Hayem — Object of Table E — Hayem considers the white and red corpuscles both in mammals and ovipara to be independent of each other — The lymphoid elements from all sources are in reality the direct or indirect progenitors of the red corputich's — General conclusions . . 190-198 MIGRO-PHOTOGEAPHS AND THEIR DESCRIPTION . . 198-230 APPENDIX. Original communication of Prof. Bizzozero (Jan. 14th, 1882) — Leader in the "Lancet" "On a New Blood Corpftscle" (Jan. 21st, 1882) — Author's Letter to " Lancet '' (Jan. 23rd, 1882) — Action of the Birmingham Philosophical Society (Feb. 9th, 1882) — Second Communication of Prof. Bizzozero (March 11th, 1882) — Second Leader in the " Lancet," " Norris and Bizzozero" (March 18th, 1882) — Author's Letter to the " Lancet" (April 8th, 1882) 230-255 INDEX 256-274 LIST OF MICEO-PHOTOGRAPHS AND ILLUSTRATIONS. Fig. 1. Barrier of Newton's rings to show colourless discs, 200. „ 2. Arrangement for viewing adhering inatters after removal of liquor sanguinis, 200. ,, 3. Arrangement for submitting adhering corpuscles, &c., to the action of fixing vapours, 200. ,, 4. Arrangement for removing surplus blood by means of air or other gases, 200. Photo 1. Ordinary red biconcave discs, 201. ,, 2. Ordinary white blood corpuscles, 201. ,, 3. Curvilinear indentations of red discs by invisible discs, 201. ,, 4. Invisible or colourless discs packed round by red discs, 201. ,, 5. Example of less complete packing of colourless discs by red discs, 201. ,, 6. Invisible discs as seen in liquor sanguinis, the refractive index of which is altered, 201. ,, 7. Contracting effects of long continued action of saline and staining of invisible discs by haemoglobin, 202. „ 8.] ,, 9. > Mosaic groups of young discs isolated from the blood, 202. „ 10. J ,, 11. Colourless discs undergoing fusion and granulation, 202. ,, 12. Isolated colourless discs in smooth and granular state, 202. ,, 13. Isolated colourless and faintly-coloured discs, 203. „ 14. Intermediate and fully-coloured discs, with colourless discs lying as liquid in the interstices between them keeping them asunder, 203. „ 15. 1 Intermediate and colourless discs preserved with osmic acid, 16. ) 203. ,, 17. Corpuscles submitted to dry osmic acid vapour at the ice-cold temperature, which preserves more or less perfectly the biconcave form of the colourless discs, 203. ,, 18. Bo-called hsematoblasts, resulting from granulation of some of the intermediate discs, 203. ,, 19. Mosaic group of coloured, surrounded by colourless corpuscles, 204. ,, 20. Background of invisible discs brought into view by the penetration of aniline brown into the interstices between them, 204. ,, 21. ) Invisible and slightly-coloured discs fusing into liquid ,, 22. J masses or pools, 204. ,, 23. 1 Difference in the appearance of spread blood when dried ,, 24. [ spontaneously or rapidly, 204. ,, 25. Invisible discs brought into view in the liquor sanguinis by staining with carmine, 205. ,, 26. Debris of red discs undergoing disintegration {vide also Photograph 23), 205. 27 1 " 28* ' Lymph and splenic discs obtained quickly after death, 205. ,, 29. ) Changes which occur in the lymph and splenic discs by ,, 30. 1" the time these organs are cold, 205. XVlll List of Mkro-PJiotograjihs, etc. Photo 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70. 71. Lymph discs extended by water, 206. Enlargement of lymph discs by fusion and aggi'egation, 206. Appeax-ance presented by fused lymph discs, 206. Lymph discs undergoing fibrillation, 206. Lymph fibrin produced by coalescence and spreading of lymph discs, 206. Primary lymph discs showing cell wall by osmosis, 206. Lymph corpuscles coalescing to form a thick liquid, 207. Lymph discs rendered irregularly spherical by 2 per cent. saline, 207. Lymph discs taking on the biconcave form, 207. Artificially produced biconcave discs, 207. Mvelin masses from lymph corpuscles taking a biconcave 'form, 207. A white corpuscle from which the pellicle has disappeared, 207. White corpuscles contracting and discharging liquid proto- plasmic contents, 208. White corpuscles in which the nuclei also appear much contracted, 208. Granules formed by breaking up of young colourless blood discs, 208. Semmer's corpuscles on surface of coagulum, 208. Coloured and colourless constituents of young blood discs, 208. Micrometer scale for measuring objects in micro-photo- graphs, 208. Photograph showing contrast of colour of liquor sanguinis and air spaces, 209. Contrast of liquor sanguinis, air spaces, and invisible discs in a case in which a colloid has been added to the blood, 209. Specimen near to the barrier, red discs thinned and liquor sanguinis tinted with haemoglobin, 209. Specimen near to the barrier in which red discs have been prevented giving up their hasmoglobin by the use of a colloid, 209. I Photographs of the same spot near to the barrier, at an I" interval from each other of 18 hours, no colloid used, 209. Invisible corpuscles in spherical state, 210. \ Invisible corpuscles fusing into groups or masses, 210. Masses formed of fused invisible corpuscles undergoing annulation, 210. Diffused edged corpuscle. It divides the permanent from the fugitive group of discs, 210. Transition of colourless discs into fibrin, 210. Group showing the entire series of mammal blood discs, 211. Isolated colourless discs, 211. Isolated colourless discs in corrugated state, 211. Granules from disintegration of colourless discs, 211. Granules from colourless discs forming fibrin, 211. Incipient rosette corpuscles from diffused edged ones, 211. Fully-formed rosette corpuscles, 212. Rosette granules, 212. Rosette corpuscles on warm stage, 212. I Granules from partly-coloured discs, so-called hasmatoblasts j of Hayem, 212. List of Micro-Photographs, etc. xix Photo 72. Groups of rosette granules, so-called groups of hsematoblasts, 212. ,, 73. ) Groups formed by the fusion of the colourless portion of ,, 74. j" partly coloured discs, 213. ,, 75. Granules yielded by young corpuscles, forming fibrin, 213. ,, 76. Cutting up of discs into fragments by contracting fibrin threads, source of so-called hasmatoblasts, 213. ,, 77. Granules of white corpuscles. Fibrin threads always absent. 213. ,, 78. Entire corpuscles breaking up into fibrin, 213. 79.] ,, 80. r Rosette corpuscles giving rise to radiating fibrin, 214. „ 81.) ,, 82. Discs yielding fibrin without previous separation of con- stituents, 214. , 83. Group of oviparous blood corpuscles showing all stages from colourless to full red, 214. ,, 84. Nucleated corpuscles of ovipara with invisible margins, analogue of colourless discs of mammal, 214. ,, 85. 1 Formation of fibrin from the coloured substance of young ,, 86. j corpuscles and their granules, 215. „ 87. Mass of granules from advanced lymph corpuscles and colourless discs, 215. ,, 88. A similar mass fused into a skin of fibrin, 215. ,, 89. Young corpuscles exhibiting the tendency to swell and spread, 215. ,, 90. Masses of so-called hsematoblasts due to disintegration of voung coloured corpuscles, 215. 91. 1 " qo' I Young corpuscles breaking up into so-called hsematoblasts, :; 93:} 215. Fig. 6 and Photographs 94 to 100 illustrate, in contrast with the author's, M. Hayem's view of the development of the blood, 216. Photo 101. Primary lymph discs, 217. „ 102. Primary lymph discs flattened by compression, 217. ,, 103. Primary and advanced lymph discs isolated from the liquor lymphae, 217. Specimens exhibiting the remarkable tendency of advanced lymph discs to spread upon the slide when submitted to examination. It is in this way that fibrin films are formed in lymph, 217. Light and dark granules due to the disintegration of primary and advanced lymph corpuscles, 218. 110. Primary and advanced lymph discs from the thyroid gland of the calf, 218. 111. Thyroid gland discs from the calf preserved from spreading by cane-sugar, 218. 112. Advanced lymph discs after the action of aniline blue, 218. 113. Effects of saline aniline blue on lymph discs of the sheep, 219. ^^. \ Same specimen before and after adding aniline blue. The , , ^' [ granules only which belong to the advanced discs swell ^^^- ) and stain, 219. 116. Contraction of the primary and the extension of the advanced discs under the influence of saline aniline blue, 219. 117. Lymph discs of the pig, showing intermediate stages between primary and advanced corpuscles, 219. XX List of Micro-Photof/raphs, etc. Photo 118. Advanced discs with granular debris attached, having the same chemical reactions as the capsules of the pi'imary disc, 219. 119. Primary lymph discs which have escaped into bubble-spaces and spread down upon the slide. Their dark appearance must be noted, 219. 120. Primary and advanced lymph discs imperfectly preserved^ 220. 121. Specimen better preserved by cane-sugar, 220. 122. ) J23' I Primary lymph corpuscles, the cellular character of which 124' [ ^^ shown by osmosis, 220. 125. Spherical white blood corpuscles, 221. 126. Primary lymph corpuscles swollen bodily by alteration of the environment, 221. 127. White corpuscles reduced in size by J per cent, solution of salt, 221. 128. Uninuclear stage of the white blood corpuscle, 221. 129. Nuclei of white blood corpuscle in the process of division,, 221. 130. Binuclear white corpuscles in the process of division, 221. 131. Multinuclear white corpuscles, 221. 132. Nuclei swollen by stains and capsule dissipated, 221. 133. Specimen showing capsules of white corpuscles, 221. 184. White corpuscles with pellicle intact, 222. 135. White corpuscles and their nuclei contracted and ruptured with emission of contents, 222. 136. Protoplasm of white corpuscle, granular and stained, 222. 137. ) Annulatiug masses of fused colourless discs eventuating in 138. j" ring forms, 223. 139. ) 140. I Conversion of single discs into ring forms, 223. 141.) 142. Fibres formed by splitting of rings, 223. 143. ) Aunulation as seen in fat or oil on the surface of water,. 145. I 223. 144. 1 Annulation occurring in myelin submerged in saline solu- 146. [ tion, leading to the production of rings and biconcave 147. ) discs, 223. 148. Blood shapes comparable with myelin shapes, 224. 149. Colourless clear-bordered nucleated cell of embryo, 224. -.g-i' [Nucleated intermediate corpuscles of embryo blood, 224. 152. Development of colourless nucleated corpuscle of embryo in blood, 224. 153 Development of nucleated colourless corpuscle of embryo in the spleen, 224. 154. Development of colourless nucleated corpuscles in bone- marrow, 224. 155. Formation in bone-marrow of red discs from colourless nuclei, 224. 156. Coarsely granular pigment cells of the embryo bone-marrow^ 224. 157. Freed nucleus of bone-marrow corpuscle, 224. 158. ) Transitions from the coarsely granular pigment cell to the 159. 1 red nucleated corpuscle, 225. 160. Groups of coloured nuclei from the bone-marrow of the adult guinea-pig, 225. TJf^ Tntrodnction. xliii lie assumed its identity with the inland corpuscles, he committed the error which Avas repeated seventy-nine years later, when, in 1852, pathologists, having discovered that hypertrophy of the glands was associated with increase of white blood corpuscles, came to the conclusion that the function of the blood glands was to produce white blood corpuscles. I have shown that the function of the blood-glands is not to produce Jeucoci/tes, such as we see in the blood, but, on the contrary, free nuclei, which become its colourless discs. Our misfortune has consisted in failing to recognise that a progres- sive development continually goes on in the blood glands by which young and immature cells are deprived of their capsules and their nuclear discs set free. This process has a certain per centage of failure which may be regarded as normal to it, and which within certain limits is quite consistent with health. The number of leucocytes in any specimen of blood indicates the extent of this failure, because they represent the cells which. that these colourless ellipsoidal cells are derived thus perfected from the lymphatics, bone-marrow, and spleen. As a matter of fact, my work may be regarded from beginning to end as a demonstration that these corpuscles are not decolourised discs, but youuf/ discs wliieJi (ire paasinij from the colourless towards the fully coloured condition. As to the new names proposed, I am bound to say I regard them as both inaccurate and inadequate. In the first place, blood discs are not cells ; and in the second, discs possessing every shade of colour exist between achromac.ytes and chlorocytes and these remain undesignated. The green corpuscles are those which I frequently refer to as the "green, lustrous, or diffused-edged corpuscles," and the most coloured of which photogi-aph nearly as dark as the red discs [vide Photograph 59). These mark the limit of the fugitive yroup of discs which is constituted of those colourless and partially coloured discs which in their degenerations form fibrin and determine coagulation. The term achromacyte would be better applied to the colourless stage of the red nucleated corpuscle of the ovipara, because this is a true cell ; but on the whole it seems to be undesirable to coin designations, however satisfactory they may seem, until we are agreed among ourselves upon the facts, for such terms are catching, become current, and, not bcin<^ held tentatively, often in the end prove stumbling-blocks to scientific progress. No better example could be found than the confused use of the temi hcemntnblast, which is now applied by different authors to widely-diverse elenaents, xliv Introduction. having escaped capsular degeneration, become developed in the large lymphatics and thoracic duct and in the blood into uni- nuclear and multinuclear cells, and are there seen as the white corpuscles. At this point we get a glimpse of the nature of the defective function of the glands which gives rise to leukhfemia. The production of leucocytes by the glands in the place of nuclear discs is not to be regarded as an absolute failure of their blood-forming function, but rather the reduction of it to a lower and more sluggish type, for there are strong reasons for thinking that the leucocytes of the blood shed their nuclei, and that these pass through the stage of colourless discs and become ultimately red corpuscles. To the uninuclear lymph cell, as found in the blood-glands, I have given the name of the primnrij lymph cor- puscle, and to its liberated nuclear disc that of the advanced lymph corpuscle. Such few of the primary ones as escape capsular degeneration become the white corpmscles, while the main body which have undergone this change go to form the colourless discs of the blood. In a restricted sense the conjecture of Professor Grulliver was quite correct when he said: " That the lymph globule is an immature cell which may change in the blood, or even in the thoracic duct or lymphatic vessels, into the larger and more perfect pale cell of the blood is very probable." (Note cxlvi., p. 282, Hewson's Works.) This of course could only happen with the primary lymph corpuscle. It will naturally be anticipated that in the event of correct views as to the mode of the development of the blood having been obtained by these researches, new light will be thrown iipon those abnormal departures which we recognise as disease, and this has proved to be the case, not only in leiikhfemia, but also in the more frequent derangement, anaemia. It transpires that the mode of arrangement of the haemoglobin in the individual corpuscles is such as to be consistent only Avith a view wliicli considers the corpuscles to begin their career in a colourless state, and to assume equal increments of haemoglobin in equal times, we are thus enabled to explain how it comes about that corpuscular deficiency is associated with a greatly disproportionate loss of --" Introduction. xlv haemoglobin, and to show that this rests in a definite law, to which, with certain reservations, all cases of anaemia may be referred. In the concluding sections I have sought to point out the part which the spleen and the bone-marrow play in the production of the blood of the ovipara, and have explained the close analogy which subsists between the development of mammalian and oviparous blood corpuscles. SECTION I. Part I. On the existence in Mammalian Blood of a i)t'6vioushj unknown Corpuscle, ivhich explains the orirjin of the Pied Disc and the formation of Fibrin. The discovery which forms the babis of this research was made dm'ing a protracted attempt to render photography available for the preservation of observations made with the high j)owers of the microscope.* In order to carry out this object it was necessary to materially advance the existing state of micro-photography, and in the nmneroiis preliminary experiments which this involved, a little blood drawn fi'om the finger was commonly used as a test specimen. This led to the accumulation of a large number of photographs of human blood. In some of these photographs corpuscles were observed which, although obviously in the same plane, were barely visible, and it was found that they could not be seen at all in the original specimens, however carefully looked for. Photography had therefore detected the existence of corpuscles which differed so little in refractive power and colour from the liquor sanguinis as to be invisible to the eye. * It was desired to do this for the following reasons : — 1. It removes the doubt and distrust which are inseparable from hand drawing and engraving, however carefully and conscientiously performed, by furnishing illustrations which are as indisputable in the shape of evidence as the original specimens from which the photographs are taken. 2. It preserves perishable results so perfectly as to allow extensive comparisons of specimens to be made with a minimum amount of labour and fatigue. 3. Its well-known power to make apparent minute differences of structure and colour, which baffle the most trained eye, give it a claim to be regarded as a new and valuable iiietliod of research in Histology and Pathology. 2 Dr. Noeris un Mammalian Blood. Eefiection on this curious fact gave rise to the opinion that possibly other corpuscles might exist, having precisely the same refractive index and actinic value as the liquor sanguinis, and that such would not only be invisible, but also incapable of being photographed. Such a suspicion being aroused fi-esh specimens of blood were submitted in extremely thin layers to the most careful scrutiny, in the hope that such corpuscles might in some indirect manner betray their existence. Under this neiv condition it was observed that the red corpuscles, as they moved about in the liquor sanguinis, occasionally became indented in outline, apparently in conse- quence of impinging against some unseen circular bodies less yielding than themselves.* By this observation the previous inference was materially strengthened, and a method was ulti- mately devised which rendered the presence of such corpuscles absolutely certain. This method was based upon the idea that the spaces which these corpuscles occupied could not be otherwise filled, and hence if the liquor sanguinis could be drawn off in a great measure from a very thin layer of blood the red corpuscles would become applied to these bodies, and so form a new surrounding, which would ren- der their presence obvious. This plan, when properly carried out in detail, as explained below under the heading of " The packing method," is most successful, for it displays both the size and number of these hidden corpuscles by a simple mechanical arrangement, which involves no alteration of the blood or addi- tion of any foreign substance or re-agent to it, and allows of its examination within a few seconds of being shed. By the * Ordinarily these corpuscles are more limpid than the red ones, and are indented by them, as seen in Photographs 9 and 12, Plate III. : sometimes they even rmi in finger-like processes between the red cor- puscles as a liquid might do. Examples of this may be seen in Photographs 15 and 16, Plate IV. When they retain their circular outline and indent the red corpuscles it is probably owing to their having effected adhesion to the slide or cover glass. De. Noeeis on Mammalian Blood. 8 methods which follow the existence of these corpuscles may be fully demonstrated.* METHODS OF EXAMINATION. BY PACKING. From a number of thin cover-glasses a slightly convex one is selected by ascertaining that one surface (the convex) gives by reflected light a sharp image of the window bars, or gas-light, and the other a blurred and indistinct one. This cover is strapped, with its convex- surface downwards, upon a microscopic slide, so firmly as to produce a series of Newton's rings of an elongated form {vide Plate I., Fig. 1). Two objects are gained by this arrangement. 1. The glasses are everywhere in such close proximity as to admit the corpuscles flatways, and in single layer only. 2. In the part occupied by Newton's rings the proximity is much less than jo.o-oo^^ ^^ ^^ inch, and thus presents a barrier to the passage of the corpuscles, whilst allowing free passage to the liquor sanguinis. By this means the corpuscles are kept in the part marked A, whilst the liquor sanguinis is filtered ofl' into B. This packing of the red corpuscles in part A causes them to mould themselves around the invisible bodies present. On Plate II., Photograph 3, is represented a specimen of blood from which the liquor sanguinis has been partially withdrawn by the method just described. The dark masses in this specimen consist in some cases of single deformed or indented red corpuscles, and in others of several such corpuscles fused together. Many of these masses will be seen to be bounded by concave dejiressions and if some of these concavities are * The photographs illustrating Parts I., II., and III., Section I., are from specimens magnified 476 diameters, and those of Part IV. 500 diameters. The true relative sizes are therefore preserved. The actual size of any object may be obtained by measurement with the micrometer, Plate IX., Fig. 48, which is divided into 10 and 20,000th3 of an inch. 4 Dr. Norris on Mammalian Blood, carefully examined it will be observed that they are due to the presence and influence of certain circular bodies, which are either pressing into the red corpuscular masses, or forming a basis around which these masses are applying and adapting themselves. The latter view is probably the correct one, inasmuch as the red corpuscular masses may often be seen to swim freely about in the liquor sanguinis, still retaining the curved outlines, and fitting into these curved outlines delicate and nearly invisible corpuscles may be sometimes detected. This being so, it is fair to consider that the concavities in the cases where no corpuscles can be seen are also produced by the presence of others which are still less visible. The photograph just described represents, as stated, partial with- drawal of the liquor sanguinis. If this liquid is more perfectly removed we get such specimens as are represented in Plate II., Photographs 4 and 5. Here the whole of the dark part seen between the invisible corpuscles is formed of red corpuscles closely massed together, and by this means the spaces in which the invisible corpuscles lie are rendered obvious, and although the blood may be said to swarm with these corpuscles they escape observation, because their colour and refractive index coincide exactly with that of the liquor sanguinis. In Plate II., Photograph 5, the packing is less complete, and the individual red corpuscles forming the dark background can be detected. BY ALTERING THE REFRACTIVE INDEX OF THE LIQUOR SANGUINIS. If we place upon the tip of the finger a minute drop of saturated solution of salt, and prick through it, so that the blood may flow directly into the saline solution, the refractive power of the liquor sanguinis is modified, and it is found that if we run this mixture of salt and blood between glasses pre- pared according to the packing method before described, we can then see the outlines of these colourless, circular bodies where they lie in contact with each other, and we find that many of the clear spaces which have hitherto been supposed to consist Dr. Nokris on Mammalian Blood. 5 of liquor sanguinis only, are really occupied by these colourless discs, as seen in Plate II., Photograph 6. After a time speci- mens thus prepared become tinted with haemoglobin, and this stains the edges of the colomless discs, and renders them still more apparent, as in Plate III., Photograph 7. BY ISOLATION. From what has been said, it is obvious that these corpuscles cannot be properly examined so long as they remain submerged in the normal liquor sanguinis ; it is therefore necessary to devise some means by which they can be h'eed from this liquid, and at the same time isolated as much as possible fi-om other corpuscles. Numerous observations having pointed to the fact that the adhesiveness of the blood corpuscles to foreign sub- stances, e.g., glass, was inversely as their degree of colour, this was taken advantage of as a means of separating them from the liquor sanguinis and from each other. The kind and character of the corpuscles withdi-awn will in great measure depend upon the length of time the blood is in contact with the glass. Capillarity is the principal means that has been employed to get rid of the main body of the blood. Thus cover-glasses of various and often considerable sizes were used, and these, in some cases, were firmly strapped down at both ends, with good adhesive plaster, to a slide ha%dng a hole drilled in the point of intersection of its diagonals. The blood could then be intro- duced at the central hole, or at the circumference of the cover- glass near to the hole ; then, by carefully springing up the cover- glass, by introducing a tightly-fitting wooden plug into the hole, the blood can be made to recede by capillarity into another part of the arrangement, leaving the adhering corpuscles fi-ee for examination. Instead of the plug, a fine screw working in a bush was sometimes used, for by this means the blood can be removed more gently, and also be allowed to return again over the adhering corpuscles, permitting an opinion to be formed as to their degree of visibility, etc., when so submerged. This plan has the decided advantage of being perfectly under control, and 6 Dr. Norris on Mammalian Blood. therefore more gentle and gradual in its operation. {Vide Plate I., Fig. 2.) On other occasions cover-glasses were strapped down at one end only, forming a kind of hinge, which permitted them to be raised by the screw, or otherwise, from the opposite end, and the excess of blood would then flow by capillarity to the other, fi-om whence it could be removed by blotting paper, and the adhering corpuscles retained for examination. [Vide Plate I., Fig. 3.) Another method of getting rid of the main quantity of blood was, to insert a straw or quill into a hole drilled in the glass slide, and either to forcibly blow the redundant blood into another part of the covered space, or suck it from the circum- ference towards the centre. In some cases, when it was sought to isolate corpuscles that had as yet attained little or no colour, and which are apt to spread themselves down almost immediately on the glass and become lost to observation, air that had first passed through dilute solution of osmic acid, and subse- quently through chloride of calcium was used. When displacement of the blood was effected by blowing, the arrangement depicted in Plate I., Fig. 4, was adopted, but when by suction, the rubber ball was replaced by the mouth. When such methods are employed in their simplest form groups of corpuscles are found to be adhering to the cover glass and slide, of the character seen in Plate III., Photograph 8. These mosaic groups appear to form while the coi-puscles are still submerged in the liquor sanguinis. They, result from cohesive attraction, operatmg in a progressive manner, as explamed by the Author in his papers on the formation of rouleaux and on the passage of the corpuscles through the vessel walls.* * A consideration of the causes of various phenomena of attraction and adhesion in solid bodies, films, vesicles, liquid globules, and blood corpuscles. — Proceedings of the Eoyal Society, London, 1862. Aggregation of the blood corpuscles both within and without the vessels (rouleaux). — Proceedings of Royal Society, London, 1869. Principles concerned in the extrusion (without rupture of the vessels) of the morphological elements of the blood (so-called emigration of corpuscles). — Proceedings of Royal Society, London, 1871 ; Transactions of St. Andrews Graduates' Association, 1871. Dr. Norris 011 Mammalian Blood. 7 The action may readily be imitated by smearing a little soap solution upon a glass plate, and producing minute bubbles with the aid of a capillary tube. The bubbles will be seen to arrange themselves in groups, with flattened facets, just as the corpuscles do. In the case of the latter the actioti is due to direct cohesion, while in the former it is owing to capillarity (double or indirect cohesion). It will be noticed that when one of the minute bubbles burst the others are immediately drawn up, and the whole group undergoes rearrangement, so that no vacant space is allowed to remain. It has been observed that a precisely similar thing occurs with these blood groups, and that the invisible corpuscle is the one which by falling into a liquid state, and spreading itself on the glass slide, yields up its place to the more stable ones. This sinking down of' some of the more delicate corpuscles and the rearrangement of the more stable ones, occm-s with such rapidity, that it is only by having the groups under the eye at the moment that the liquor san- guinis is removed from over and around them, that it can be seen. A moment later all is quiet, and there is nothing to excite the least suspicion that such an important modifica- tion has occurred. The first corpuscles to attach themselves to foreign bodies such as glass, are the uncoloured, and very slightly coloured, smooth corpuscles, the invisible corpuscles of the blood. But these are easily overlooked ; for they are so delicate and fragile, that when they do not melt down, so to speak, they almost invariably break up into molecules or spheroidal granules, however gently the main quantity of blood may be withdrawn by capillarity from off and around them, i.e., however carefully the glasses may be separated from each other. Another mode in which they frequently elude observation is by adhering and fusing together so as to form delicate films upon the slide and cover-glass, and they often seem in this way to furnish a basis of adhesion for the more coloured corpuscles ; for mosaic groups of these are constantly found to have a delicate layer formed of the uncoloured corpuscles beneath and around them. 8 De. Nokeis on Mammalian Blood. Ou Plate III., Photograplis 9, 10, 11, 12, and 13, show groups of corpuscles which have been withdrawn from the blood by means of their adhesiveness to sohds. Among them, the corpuscles in question may be seeu. In Photograph 9, five such may be counted, and in Photograph 10 there are three which are blending into a smooth mass, and five others which possess some colour. Photograph 11 is a group in which four corpuscles have ah-eady blended into a smooth mass, and in the upper part of the specimen a similar mass shows a tendency to granulation. Photograph 12 shows the new corpuscle in an isolated state, and also masses resulting fi'om their fusion, some of which have become granular. Photograph 13 shows numerous isolated invisible corpuscles, some of which exhibit faint traces of coloiu-. All these specimens were obtained by the plan of separating the glasses gently by the use of the fine screw, as depicted in Plate I., Fig. 3. BY OSMIC ACID VAPOUR AND COLD. As in some of the examples yielded by the previous methods there appeared to be indications that the normal form of the transparent colourless corpuscles was that of the un- altered red corpuscles, viz., a biconcave disc, it was decided to attempt the preservation of then- true form by separating the glasses over a shallow pan filled with the vapour* of osmic acid, it being well known, as pointed out by Schultze, that this vapour possessed the property of preventing change in the form of the red corpuscle. The series of Photographs 14, 15, and 16 on Plate IV. were obtained by this method, and are remarkable groups for displaying the fact that corpuscles exist of every gradation of tint, from those which are perfectly colom-less to the fully coloured red disc. In Photograph 16 we have also evidence that the coi-puscles which are freest fi'om colour possess in then' original state a biconcave foi-m. The most decisive results, however, as to the biconcave form of the new corpuscle have been obtained by the use of cold and osmic Dk. Norris on Mammalian Blvod. 9 acid vapour in conjunctiou. The slide witli the hinged cover glass {vide Plate I., Fig. 3) is wrapped up in blotting paper, and placed between two blocks of ice, and allowed to remain till it has attained the ice cold temperature. It is then un- wrapped, and the finger having been previously pricked, the blood is allowed to run in imder the cover-glass before any condensation of moistiu'e upon the slide has had time to take place. The slide is immediately placed face downwards over the osmic acid pan, and the glasses gently separated by the screw. The form of the new corpuscle can thus be perfectly preserved, as seen in Plate IV., Photographs 17 and 18. BY AJLCOHOL AND SOLUTION OF OSMIC ACID. The use of the vapour of osmic acid having proved so valu- able as a coagulant in securing the presence of, and arresting the changes in, the invisible corpuscle, other vapours and substances were used, and among the rest, alcohol. Some very successful specimens were obtained by means of this agent. The method consisted in the use of one of the hinged cover- glasses before referred to. Absolute alcohol was introduced between the cover-glass and slide till the space was filled, then a drop of blood fi'om the end of the finger being placed at the edge of the cover-glass readily finds its way between the glasses, and mixes with the alcohol. After a short time, the glasses being separated by means of a screw, groups of corpuscles are found attached to their surfaces, and in and around these groups numbers of the invisible corpuscles were to be seen. Such groups are seen in Plate V., Photograph 19. A keen sight may detect in every part of the background of the photographs of such specimens faint dark lines : these indicate the existence of a layer of phantom corpuscles which have become fused, and have spread themselves out in a delicate fibrin-like layer upon the glass. By using a two per cent, solution of osmic acid in the same manner as alcohol in the previous case, they may be much more fully preserved, and then by protracted staining they can be brought into view, as in plate V., Photo- graph 20. This specimen underwent prolonged staining 10 Dr. Noeeis on Mammalian Blood. witli alcoholic solution of aniline brown, and a complete background of corpuscles whicb were previously invisible was thus brought into view. The coi-puscles themselves have not taken the stain, but it appears to have pene- trated into the interstices between them. Plate V., Photograph 21, is from a similar specimen, but shows, in addition, that prior to the arresting action of the osmic acid many of the invisible corpuscles had become already fused into liquid masses, which appear to adhere to and surround the more coloiu'ed corpuscles. In many cases the invisible corpuscles are still sufficiently distinct and intact to show that these " fibrin or plasmine pools" originate^ fi'om then- fusion. There is reason to thmk that every part of the background of this specimen is covered with hquid of corpuscular origin. Plate v., Photograph 22, shows invisible and slightly coloured corpuscles in the act of spreading, fusion, and disintegration. It represents a still more advanced stage in plasmine formation. It will be noted that while the invisible corpuscles have refused the aniline brow^n the partially coloui'cd ones among them have become deeply stained by it, BY SPEEADING AND DRYING. Mammalian blood can be readily spread out upon a glass slide, so that the corpuscles shall exist in a single layer only. The best method of doing this is to take a strip of fiat glass about three inches in length, and a quarter of an inch in width. The drop of blood being placed between the strip and the slide, at one end of the latter, the former is smoothly and slowly moved along the glass to the opposite end. It is interesting to observe the diiference between the specimens of blood simply spread by the above method and allowed to dry spontaneously, and others in which the drying is accomplished artificially, as the spreading proceeds, by blowing large quantities of air upon it fi'om a small blast-fan, or hand bellows. In the former the spaces between the corpuscles which represent the dried liquor sanguinis are clear and transparent, while in the latter case they are comparatively Dg. NoREis on Mammalian Bloud. 11 opaque and turbid, owing to the presence of the invisible and faintly coloured corpuscles. Some distortion of the corpuscles is produced by this method, but it has the advantage of allowing their relative number to be approximately estimated. Plate v., Photograph 23, shows the appearance when drying is allowed to take place spontaneously, and Photograph 24 when it is expedited by blowing. In the latter case the fugitive corpuscles are prevented from melting down mto a film of fibrin upon the surface of the slide. There are two general principles by which these cor- puscles may be made visible while floating in the liquid of the blood. When we reflect that they have the same colour as the liquor sanguinis, it is obvious that substances having the power of tinting this liquid, but incapable of staining the cor- puscles, should render the latter visible. This is actually the case. The second principle is that of staining the corpuscles themselves more deejAy than the liquor sanguinis. The corpuscles must, therefore, in this case have an affinity for the stain. BY TINTING THE LIQUOR SANGUINIS. Three-quarter per cent, solutions of sodium chloride charged with such substances as hemoglobin, caramel, and saffron, have been found most successful. In all these cases the invisible corpuscles appear, and remain as delicate, colourless bodies, contrasting strongly with the ordinary red discs. In this method, and also in that of actual staining, there should be no depth of liquid above or below the corpuscles, as this entu-ely obscures them. They are best seen when the glasses are so closely approximated as to actually compress them, and to increase their diameter when lying flatways, and as in such cases the layer of stained liquor sanguinis is less than l-10,000th of an inch in thickness, the staining fluid requires to have in the first instance the utmost intensity : if this is not the case, sufficient difierence fails to be created. The slides should be prepared as for " the packing method." In obtaining the specimens of blood for examination the following method should be adopted : — Place upon the 12 Dk. Nokris on Mammalian Blood. end of the finger a small drop of the stainhag fluid, and with a needle prick the finger through this drop, so that the blood may, when the finger is squeezed, flow directly into the liquid, which has the double property of both preserving and tinting or stainimj, as the case may be. After mixing well with the needle on the end of the finger, the blood may be allowed to flow by capillarity between the cover-glass and slide for examination. BY STAINING THE INVISIBLE CORPUSCLE. The utmost caution is of course demanded in drawing conclusions after the addition of reagents of any kind to the blood. Such a method is always open to the objection that the reagent may produce that which is simply sought to be distinguished. This objection is met by the adoption of methods which show unequivocally that the corpuscles which take the stain are the self-same corpuscles as those which occupy the spaces that appear in the ' packing method.' Having once satisfied ourselves that such cor- puscles — and such alone — take the stain, while the ordinary red discs refuse it, we have no difficulty in displaying and distinguishing the fugitive group of discs, and in demonstrating that essential chemical differences exist between these and the hcBmoglobin group, but that in this respect they gradually merge into each other. When a staining fluid is added to blood its first action is to bring into view the invisible corpuscles as delicate white bodies, which contrast strongly with the ordinary biconcave discs ; these, then, become rapidly stained in the inverse order of their colour till a limit is reached, when no fm-ther staining occm-s. As the corpuscles take up the dye they of course become again invisible, because they assume the same colour as the tinted liquor sanguinis. After some time has elapsed they, however, reappear, having acquired a stronger tint than the liquid which surrounds them. The subject of staining is one of such great importance both as to differentiating these corpuscles from the red ones, De. Norris on Mammalian Blood. 18 and also in tracing their origin, that it has been deemed desirable to devote Section III. specially to its consideration. From the observations I have here recorded I consider that two conclusions are justifiable, — 1st, That there exist in the blood of mammalia, in addition to the well-known red and white corpuscles {lide Plate II., Photographs 1 and 2), colourless, transparent, biconcave discs of the same size as the red ones ; 2nd, That between these two kinds of biconcave discs others are demonstrable, having every intermediate gradation of colour. The origin of these new corpuscles is treated of in the second part of this Section. Part II. On the Origin of the Colourless Biconcave Discs of Mammalian Blood. The existence of these colourless biconcave discs having been demonstrated by a variety of methods, and their number shown to be considerable, it becomes important to ascertain their source. Three conjectures appear to be admissible. 1st, They may be regarded as red corpuscles which have become decolourised during the mere act of shedding the blood. 2nd, They may be considered as representing stages in the dissolution of the red disc. 3rd, They may be biconcave corpuscles which are destined by acquiring colour to become converted into the red discs. Against the view that they are corpuscles which have lost their haemoglobin in the brief interval (a few seconds) between the shedding of the blood and its examination, it may be urged, — 1st, That they are obtained in greatest perfection when those measures are adopted which tend to preserve the blood from change, i.e., cold or osmic acid. 2nd, They may be seen imme- diately the preparation is made (packing method) and before the liquor sanguinis has become stained, and they do not increase in number as time elapses. 3rd, Assuming the red corpuscles 14 Dr. Norris on Mammalian Blnnd. to lose haemoglobin, the loss must occur in such a manner as to furnish corpuscles exhibiting all gradations between a colourless and a full red biconcave disc. If, therefore, we start with the idea that the corpuscles originally are all coloured, their decolourisation in this (jraduated manner would of itself indicate a difference in nature. 4th, If a three-quarter per cent, solution of salt be saturated with haemoglobin, and a drop of this be placed upon the end of the finger, and the latter be pricked through the drop so that the blood may come at once into con- tact with fluid saturated with hcemoglohin, the colourless discs are still present as usual. It is obvious that these are not conditions favourable to the yielding up of the colouring matter. 5th, When first brought into view by the method of altering the refractive index of the liquor sanguinis, many of these cor- puscles are of a pure white colour, but they gradually become stained by the haemoglobin discharged by the red corpuscles. {Vide Plate II., Photograph 6, and Plate III., Photograph 7.) It is impossible to suppose that they first yield up the whole of their colouring matter, and then subsequently take it up again. 6th, Finally, the general behaviour of these corpuscles after the blood is shed, their tendency to break up into granules, to lay themselves down as delicate films, to form networks ; in a word, their fibrin-forming property is totally opposed to the con- ception that tliey were once red discs.* The second conjecture, that they are red discs which have lost their colour as a preliminary step towards dissolution, has no facts to lend it support, while it is easy to show the existence in the blood of dark red granules, to which it is difficult to attach a meaning, unless we regard them as red corpuscles undergoing disintegration. These often occur in masses as in Plate VI., Photograph 26 ; but the same disin- tegrating action may be traced in single corpuscles. The third supposition, that they may be biconcave discs which are gradually assuming colour, and which, therefore, exhibit every gradation of tint during their transition stages, * Vide Section II., Page 41, Dr. Norris on Mammalian Blood, 15 necessarily involves the consideration of the existence of (t source, internal or external, from which the blood can be continually supplied with the large numbers of colourless biconcave discs which are seen to be present in it. We are thus naturally brought to the consideration of the morphological elements found in and derived from the lymphatic glands and spleen. LYMPH AND SPLENIC CORPUSCLES. It is desirable, in the first place, to state that all observations made on the corpuscles of the glands and spleen are untrust- worthy and comparatively worthless unless made almost imme- diately after the removal of these organs from the body, and while they are still warm and fresli ; for typical and unchanged examples of splenic and lymph corpuscles can only be obtained directly after death, or by the method of immediate and rapid freezing. This fact has not to my knowledge been previously urged, and it will, I believe, account for many of the contradictory state- ments made by different investigators respecting the nature of the glandular and splenic pulp. The changes of which these bodies are susceptible may be described as Enlargement, Aggregation, Fibrillation, Spreading, or Lamination. Enlargement. — Soon after death the lymph and splenic corpuscles undergo change both inform and size. The average diameter of the lymph and splenic corpuscles of the bullock, pig, and sheep, when obtained from warm glands or spleen, or glands and pieces of spleen which have been frozen, is 4-20,000ths of an inch. These measurements were always made upon examples which were free from the disposition to aggregate or spread — vide Plate VI., Photographs 27 (lymph) and 28 (splenic). As the organs cool (especially is this the case with the spleen), the corpuscles undergo change of form and mcrease in size, attaining diameters of 5, 6, 7, and 8-20,000ths of an inch, the average being about 6-20,000ths of an inch. What this spontaneous increase of size is due to is not very apparent, but we know 16 Dr. Norris on Mammalian Blood. that any alteration made in the envii'onmeut of these bodies is attended with important changes of this kind. If, for example, we add one per cent, solution of sodimn chloride to the fresh splenic corpuscles of the pig they swell up, and appear to gain greater smoothness, and to display considerable body. The behaviour of the lymph corpuscles when treated with water is also remarkable. They often swell up into globular masses, having diameters of 15-20,000ths of an inch. , This property was well known to Hewson. Plate VI., Photograph 29, shows spontaneous enlargement; Plate VI., Photograph 30, after addition of one per cent, saline solution ; and Plate VII., Photograph 31, after addition of water. The highly swollen coi-puscles in this specimen were so faint that it was necessary to stain them, hence their dark colour in the photograph. Aggregation. — These corpuscles readily coalesce with each other, forming larger masses. These may be distmguished from merely swollen states by their superior density or opacity ; some- times they coalesce to such an extent as to form a thick liquid, which will stream down the slide. Examples of their aggre- gated states may be seen in Plate VII., Photographs 32 and 33. Fibrillation. — The corpuscles frequently adhere to each other and become extended into fibres, as in Plate VII., Photograph 34. Spreading and LAinNATiON. — Some of the corpuscles frequently spread, coalesce, and melt down upon the glass into a continuous soft film, to which others, less susceptible to this action, adhere. Plate VII., Photograph 35, represents this condition. The singular manner in which these simple structures behave, both in relation to each other and to the surfaces with which they are necessarily brought into contact, when submitted to microscopic examination, indicates that they are very little removed in their essential nature from liquids. They appear, in fact, to occupy an intermediate position between limpid liquids and j)asty solids, and may, according to their surroundings, exhibit plienomena which belong to either one or the other Dr. Noeris on Mcnnmalian BJood. 17 condition, and hence they sometimes lose all differentiation of parts and act precisely like liquid substances. It is this behaviour which renders it so difficult to arrive at their true form and constitution. The general Hquid character of these coi-puscles may be judged of by the disposition which they display to coalesce, to spread, or lay themselves down into soft films, which sometimes run like a treacley liquid. ( Vide Plate YIII., Photograph 37.) Varying degrees of liquidity, however, exist among them, for some have a much greater power of retaining their shape than others. The same variation in behaviom- is also seen with reagents. The corpuscles most prone to change are the oldest or most developed. This, it will be noted, is precisely opposite to what occurs with the blood corpuscles. The lymph and splenic corpuscles are constantly spoken of as globules, and are generally held to be sjjherical in form. This has arisen fi'om the difficulty connected with ascertaining their real form, and from their proneuess like the blood disc to change and assume the globular shape. In then- normal state they are discoid bodies, with numerous slight irregular depressions upon their plane surfaces, which give to them their granular or cor- rugated appearance. Having a specific gravity slightly less than the liquid in which they exist they invariably float, as cork discs would do, with their plane surfaces uppermost. Occasionally, by dexteroiis pressm*e upon the cover-glass, they may be made to turn over, and then- true form is revealed. This can rarely be done. Their discoid form can, however, be determined by indirect methods, one of which is as follows : — Ascertain by the micrometer the average diameter of a number of these bodies, to be as usual from 4 to 5-20,000ths of an inch, and then take a slide arranged as in the method for packing, which will only allow blood corpuscles to pass in Jiativays. If the lymph corpuscles pass between these glasses without material increase of diameter they must be regarded as discs. 18 Dk. Norris on Mamnuilian Blood. They may also be rendered irreg-ularly spherical by means of a two per cent, solution of salt. They then become smaller in diameter, and roll over easily, and appear very like blood cor- puscles which have taken on irregular cup-sliaped forms. {Vide Plate VIII., Photograph 38.) As before stated, these corpuscles when unaltered are discoid bodies, with numerous slight irregular depressions, which give a granulated appearance to their plane surfaces. These depressions appear to be the commencement of the process or operation by which the disc is eventually rendered biconcave ; for if the specimens of lymph are preserved for a time under sealed cover glasses they may be seen to undergo conversion into biconcave discs, and the transition stages of the process may be watched. This property of becoming biconcave appears to belong to the corpuscle as a physical substance, rather than as an anatomical structure, because part of the corpuscle will become smooth and regularly biconcave, while the other part still retains the character and appearance of a lymph corpuscle ; hence we have the instructive spectacle of one part of the same corpuscle having the character of a colourless biconcave disc, and the other that of a comparatively unaltered lymph corpuscle. [Vide Plate VIII., Photograph 39.) The fact, too, that biconcave discs can be artificially produced by placing certain colloid substances in the proper relation to each other is a further argument in favour of this view. [Vide Plate VIII., Photograph 40.)* This capacity of the lymph and splenic discs to undergo conversion into smooth colourless biconcave discs seems to point definitely to the source of the colourless biconcave discs found in the blood. The reader will, however, find this aspect of the subject treated in much greater detail in Sections V. and VII. * For further information on the causes of biconcavity the reader is referred to Part IV. of this Section, Diu NoRRis on Mammalian Blood. 19 Comparison of the Lymph, Splenic, and White Blood Corpuscle. — A great deal of conflicting statement exists as to the relation which these bodies bear to each other. Many writers speak very loosely of the identity of the lymph and splenic corpuscles with the white blood corpuscle. Others are more critical, and claim that important distinctions exist between these bodies. Professor Gulliver is among the latter, and says : " The globules of the chyle, of the thymus fluid, and of lymph, are smaller, and differ in structure from the pale globules of the blood. In these last there are two, three, or four nuclei, easily seen when the envelope is made more or less transparent or invisible by acetic, sulphurous, citric, or tartaric acid. But the globules of chyle, of lymph, and of the thymus fluid, like the nuclei of the red corpuscles of the blood,* are only rendered more distinct and slightly smaller by any of these acids, so that the central part presents no regular nuclei, or divided nucleus, such as are contained in the pale globules of the blood. In short, these last named globules have the characters of perfect elementary cells, while the former globules resemble and probably are nuclei or immature cells." Grray also speaks of the splenic corpuscle as a nucleus. No one can compare Photographs 27 and 28, Plate VI., with Photograph 2, Plate II., without being astonished that bodies so essentially unlike in size, form,, and colour, should have been so confounded. 1st. The lymph and splenic corpuscles are discs, having a diameter varying from 4-20,000ths to 5-20,000tlis, and a thick- ness of about l-10,000th of an inch. 2nd, The white blood corpuscles are spheres, having a diameter varying from 5 to 10-20,000ths of an inch. 3rd, The lymph and splenic corpuscles consist of small uni- nuclear corpuscles, and of free disc shaped nuclei, and it is the latter only which enter the blood to any extent in health. * The nucleated corpuscle of the lower vertebrates is here referred to. 20 Dr. Norris but not twice this. In some of my best specimens the corpuBcles have undergone no compression, as can readily be known from the fact that they have not increased in diameter beyond that of the normal biconcave disc. (Compare Photo- graphs 1 and 4, Plate II.) Again, local causes act locally, and if these colourless corpuscles were produced by compression due to the proximity of the glasses, they would occupy invariably the part nearest to the rings, but the fact is, fewer of these corpuscles can be seen near to the barrier, because they have formed adhesions to the glass before reaching this point. They are distributed over the entire space, often right up to the edge of the specimen — in fact the peculiar adhesive- ness of the corpuscle constantly causes it to be filtered out or held back before the rings are reached, and if the rings are sufficiently distant from the point of ingress of the blood, this will always be the case. The power of these colourless discs to adhere in this manner, (like the white corpuscle,) while the red ones remain unaltered and sail freely about and among them, is itself an evidence that they are something different in kind. Again, any point of arrest in any part of a specimen gives rise to packing, and displays these corpuscles — hence they are constantly seen in the little patches of packing which occur about air-bubbles, in parts of the specimen, where great fi-eedom of movement without modification of for))} is possible. Side by side with these corpuscles are others which have obviously undergone no change of colour. All are subjected to the same conditions. Is it possible that some should be absolutely pressed white, while others in immediate contiguity undergo no change? Photography is an excellent test for minute shades of yellow colour, and as it renders the extremes of these corpuscles, black and white, we know that the amount of haemoglobin present in the first case is exceedingly great in comparison with that in the other. Dr. Noeeis on Mammalian Blood. "49 The afifirmation made by this writer of having repeatedly *' watched the transformation of red corpuscles into colourless ones" while using this method demands more than a passing notice. It is quite true that as the corpuscles pass within the outermost system of rings they become paler, and this because they become thinner, a fact which is known by the increase of their diameter. As the Liquor Sanguinis becomes more charged with haemoglobin (derived from the mass of corpuscles, and not from one more than another) the flattened corpuscles will become more and more obscured, indistinct, and faint, because the contrast between them and their surroundings becomes less and less. Under such circumstances they may become barely visible, and, perhaps, quite invisible, and this not because they have become colourless, but because the Liquor Sanguinis has become coloured up to a like intensity with themselves. For the determination of matters of such delicacj^ the average human eye is an inadequate colour instrument, and requires to be supplemented by photo- chemical tests. It is also impossible to observe these differences properly without a standard of colour. By means of photography we can transmute with extreme precision these shades of yellow colour into degrees of black and white, which every eye can estimate with equal correctness. The air bubbles present in specimens being absolutely free from colour, constitute an excellent standard of comparison for the iuconstants, viz., the corpuscles and the Liquor Sanguinis. The 2iormal tint of the new corpuscles is closely that of the air bubble, and precisely that of the normal Liquor Sanguinis. The normal Liquor Sanguinis is not quite as colour- less as the spaces of the air bubbles, for as soon as blood is shed hemoglobin begins to diffuse slowly into the Liquor Sanguinis, and, as time goes on, this liquid becomes deeply tinted, and if at the same time the red cor- puscles become flattened by any means, they are lost to view in it. 50 De. Nokris on Mammalian Blood. The new corpuscle stains slightly with the Liquor Sanguinis, so that it is seen at its best when the tint of the plasma is nearest to that of the air bubble, i.e., when it is fi-eest from haemoglobin. These statements apply to blood, under the usual conditions in which it is examined ; but it is quite possible to prevent the staining of the Liquor Sanguinis altogether. I have ascertained that colloids, such as gum acacia and albumen, entirely prevent the exosmose of the hasmoglobin into the Liquor Sanguinis. They are therefore of the greatest use in testing for the presence of this corpuscle, and for the intermediates, for they j^reserre all the colour in the corpuscles^ and therefore prevent the delicately-tinted intermediates from fading away into invisibility, by the combined eiiects of loss of colour" on their own part and its gain on the part of the surrounding medium. Colloid Method. — Eeduce a little diy soluble albumen to''' the state of fine powder, and having pricked the finger, stir up well with the blood, as it lies on the finger, a small portion of the powder ; run the blood beneath mica or glasses prepared for the packmg method. When the colouring matter is thus prevented from leaving the corpuscles, there is no fading away of the red corpuscles at the barrier ; or, to speak more properly, they do not become hidden in the stained Liquor Sanguinis ; and this is the case even after the specimens have been kept for eighteen hours. This experiment, it must be borne in mind, is of a crucial character, for the colom'ed corpuscles do not yield up any of their haBmoglobin, yet the invisible corpuscle is present as usual. It cannot, therefore, be a decolourised red corpuscle. Plate X., Photograph 49, is intended to show the contrast of colour between the air spaces and Liquor Sanguinis soon after the blood is shed. It will be observed that the Liquor Sanguinis is of a darker tint, owing to the presence in it of haemoglobin, derived from the corpuscles. * Soluble albumen may be obtained of R, W. Thomas, 10, Pall Mall, London. Dk. Nokeis on Manuualian Blood. 51 Plate X., Photograph 50, is an example m which the colouring- matter has been prevented from exuding from the corpuscles by the use of a colloid — in this case albumen. The air-spaces and the Liquor Sanguinis are here seen to be very nearly of the same tint, [ride upper left-hand corner in the intervals between the unpacked corpuscles.) The invisible and intermediate corpuscles are brought into view in the packed part of the specimen, and thus a demonstration is afforded that such corpuscles are not decoloiirised red ones, for no colour has passed into the serum from am/ of the corpuscles. Plate X., Photograph 51, represents the appearance imme- diately contiguous to the rings of Newton. The Liquor Sanguinis, as compared with the air-spaces, is of a very dark tint, indicating the presence of much haemoglobin. Tlie red corpuscles have also increased in diameter, and have a fainter appearance. This faintness of the corpuscles is due to two causes ; firstly, they are flattened, owing to the proximity of the glasses ; and, secondly, the contrast between them and the Liquor Sanguinis is diminished, owing to the colourisation of the latter. Plate X., Photograph 52, also represents a portion of a speci- men near to the rings of Newton, but in this case the integrity of the red discs has been preserved by means of a colloid (albumen.) The Liquor Sanguinis is seen in this case to be very nearly as colourless as the air-spaces. The discs have lost no colour, and the serum has, therefore, gained none ; and, consequently, the corpuscles appear with their usual distinctness, and not as in Photograph 51. The great preservative power of the colloid is distinctly brought out by the fact that the specimen seen in Photograph 52 had been kept for eighteen hours, while that shown by Photograph 51 was taken within an hour of its preparation. Plate X., Photographs 53 and 54, represent precisely the same spot, near to the barrier or rings of Newton, taken at an interval from each other of eighteen hours. Li these cases no preservative was used. In Photograph 53, packed among the red corpuscles, may be seen here and there a few of the colourless discs ; 52 Dr. Noreis on Mammalian liloud. and it will be noticed that Avhile nearly all the red corpuscles have in Photograph 64 disappeared in situ, the colourless ones, that lay amongst them, have remained in position, and are still visible as phantom forms in the Liquor Sanguinis among the now invisible partly decolourised corpuscles around them. By the colloid method all the corpuscles of the fugitive group can be preserved, including the colourless discs, which, however, as before, are still invisible under ordinary conditions. This method alone affords a complete answer to the objections which refer the invisible corpuscles — I. — To pressure. II. — To violence. III. — To the action of saline solutions — in fact to any view which ascribes their existence to loss of colour on the part of red, or slightly coloured corpuscles. It demonstrates, in the most absolute manner, that they are corpuscles which have never possessed enough hemoglobin to make them visible in the normal Liquor Sanguinis. The question of the effects of direct pressure upon the mammal corpuscle, i.e., of intermittent repeated compressions applied with great force from above, has also been carefully investigated, with the result of showing that corpuscles can be made in this way to give up some ol their haemoglobin, as evidenced by their becoming paler, and by the liquid becoming stained. These corpuscles, however, never iinder any circum- stances become less coloured, i.e., whiter than the liquid which surrounds them. They simply become less visible, because their own intensity of yellowness is diminished, while that of the Liquor Sanguinis is increased, and when run into clear, i.e., unstained Liquor Sanguinis, they are not invisible, as is the case with the primary disc, but much more visible, as might a j^rion be readily imagined. By no amount of pressure or manipulation can corpuscles be produced in any way corresponding to those I have designated the invisible colourless discs. All that can be done is to produce a dead level of colour between the corpuscles and the Liquor Sanguinis. ,JDr. Nokeis on Mammalian Blood. 53 I have recently discovered a very simple method by which these corpiiscles may be displayed, and which has the advantage of not requiring the cover to be strapped down, or, in fact, any plan adopted different to that by which blood is usually examined. It consists in using flexible covers in the place of the glass ones, such as thin pieces of mica or films of collodion. These covers adapt themselves sufficiently close in parts to di-aw off' the Liquor Sanguinis fi'om the corpuscles, and this induces packing in other parts, in which the colom-less disc is readily detected. Under these large flexible covers, in some parts, currents are maintained for a considerable time, and ample opj)ortunity is afforded to witness the j)henomenon of the impact of the red corpuscles against slightly visible and wholly invisible coi-puscles which have become attached to the slide. This phenomenon is, I think, one of the most impressive, for we see the effect of cui'vilinear indentation produced upon the red corpuscles, while, in the majority of cases, the most searching scrutiny fails to reveal the adhering corpuscle which is giving rise to it. It is obvious fi-om what has been said, that the detection by this investigator in one instance of haemoglobin by the aid of the micro-spectroscope is not of the least moment, for as we know that, after a time, in all cases the serum of shed blood becomes perceptibly coloured with haemoglobin ; we may readily infer that an action of this kind commences to set in immediately the blood is shed, but we may also fairly conclude that all the colom-ed corpuscles contribute their proper quota to this result. If it be true, as stated by this wi'iter, that some corpuscles yield up all their colour, while others are not perceptibly affected, this is at once an evidence of a remarkable difference among the corpuscles themselves, a point by no means to be overlooked. The experiments with the colloid appear, however, to negative such a view. Again, it must be remembered that, until I pointed out this method of filtering the serum from the corpuscular elements, such an observation was impossible, and 54 De. Noeeis on Mammalian Blood. we had no means of ascertaining whether hemoglobin was or was not a normal constituent of the Liquor Sanguinis. There exists an unknown colouring matter in the Liquor Sanguinis which gives rise to its pale yellow tint. This normal pale yellow tint must not be taken as evidence of haemoglobin. As methods can now be devised for preventing the passage of hemoglobin fi'om the corpuscles, and also of removing these bodies from the Liquor Sanguinis, we may confidently hope to be able before long to make out the nature of this colouring matter.* " Objection II. Method by Raising the Coverr — Under this head my critic writes — "By the method of raising the cover I was enabled, without the use of salt, to make some very good preparations of colourless corpuscles. After fixing with osmic acid, I also stained them. It struck me, however, that as a possible cause of this appearance of these forms of the red corpuscle, the force required to overcome the capillary attraction of the two glass surfaces, with the thin layer of fluid between * My friend, Dr. McMiinn, so well and favourably known by his researches on the animal colouring principles, has recently made this matter a subject of investigation, and has favoured me with the following note : — " The points which I have made out about the absorption band of serum are the following : The serum examined was that of the sheep, it gave a band at F. If this were due to luteine, it should have been accompanied by another in violet — it should occupy the position (m the spectram) of the luteine band — it should be rather intensified by ammonia, or by caustic soda. If, on the other hand, it were due to unoxidised bile pigment, it should be intensified by acids, it should disappear with ammonia, and it should occupy a position in the spectrum nearer to red than the luteine band ; the latter is the case, as one can easily prove, therefore the baud is not due to luteine. The band seen in serous fluids — e.g., peritoneal fluid, pericardial fluid, and that removed by a blister is probably due to luteine ; at all events, it does not appear to me at present to be due to an altered bile pigment." Further informa- tion may be found on this head in the Author's paper, Poc. Eoyal Society^ No. 208, 1880. * Cover-glasses are strapped down at one end, forming a kind of hinge, which permits them to be raised by a screw, or otherwise, from the opposite end, and the excess of blood then flows by capillarity to the other, from whence it can be removed by blotting paper, and the adhering corpuscles retained for examination. Dr Nokris on Mammalian Blood. 55 them, bad not been sufficiently taken mto consideration, nor also tbe probable effect on the more imstable red corpuscles of the sudden withdrawal of the serum." It is necessary to state, in the first place, that I have never used, nor recommended the use of solution of salt in connection with this method ; indeed, it would be impracticable, on account of crystallisation, but I have employed the method without, and with osmic acid, both in solution and in vapour. The concluding paragraph of this criticism renders it unneces- sary for me to defend this method, or, in fact, any of my methods, for the wi'iter says : — "I may be permitted to say that, after going with care through a series of observations on this subject, I am disposed to believe that the colora*less coi*puscles, which are undoubtedly seen when the blood is examined by the method of ' isolation ' are red corpuscles which have undergone post- mortem changes, prior to taking part in the formation of fibrin. ' Here is a free admission that colourless discs can be found by one of my methods, and their presence is not refeiTed to the method, but to post-mortem change in the blood. If these corpuscles are the result of post-mortem change, it is obvious that they cannot be the product of any of the methods employed. This method of "isolation" is a very important one, because it enables us to understand the relations which various corpuscles hold to the Liquor Sanguinis, and also how they behave when it is withdrawn h'om them. By employing it in its simplest form, that is without the use of re-agents, and separating the glasses in the most gentle manner possible, we may obtain groups, such as are seen in the Photographs 9, 10, 11, 12, and 13, Plates III. and IV. As a rule, however, we get only groups of coloui'ed corpuscles, without any of the colourless ones among them. As I have stated, the corpuscles of the "fugitive group" cannot weU bear the withdrawal of the Liquor Sanguinis. They owe the integrity of their form entirely to its presence, and spread down upon 56 Dr. Norris nn Martjuialian Blood. the glass surface, and are lost, just as oil globules would be, the spherical shape of which had been maintained by sub- mergence in water. The water being removed, the globules spread upon the surface with which they are in contact. There are certain corpuscles which we may obtain in addition to the mosaic groups of red ones, providing we have our glasses very clean and the right kind of siu^face, and separate them with the greatest possible care. This is the corpuscle seen in Plate XI., Photograph 59. It is a corpuscle with considerable colour, of a glistening, lustrous, or flickering character ; it has some disposition to spread, and one of its edges may frequently be seen to be laid down. This corpuscle stands between the permanent and fugitive groups, both connecting and dividing them. Generally, when the glasses are separated, these corpuscles are broken up into minute granules. A glimpse of the primary corpuscles is very rarely obtained by this method without the use of osmic acid vapour. When so obtained they are generally supported among red corpuscles. I consider that I have been able to divide the biconcave discs into three sets, which may be designated the primary, secondary, and tertiary groups. This distinction is founded on the behaviour of these corpuscles upon the withdrawal from them of the sustaining influence of the Liquor Sanguinis. I. — The Primary Group embraces all those corpuscles which melt down on the removal of the Liquor Sanguinis, and, after a time, even in the Ldquor Sanguinis of shed blood. It includes the whole of the colourless discs, and such of the coloured ones as are less tinted than those of the secondary group. 11. — The Secondary Group consists of the lustrous, flickering corpuscles. They are just barely capable of maintaining them- selves in the absence of the Liquor Sanguinis. They have considerable colour, in fact, nearly as much as those of the tertiary group. HI. — The Tertiary Group includes all corpuscles which do not become lustrous, and which can maintain a distinct outline in the absence of the Liquor Sanguinis. TJjT,. NoERis (m ]shonmaUan Blood. 57 All these corpuscles occasionally form mixed mosaic groups on the glasses. Specimens of the corpuscles forming the primary group can only be obtained isolated ft'om those of the secondary and tertiary groups by adopting perfect methods of preservation. These three classes of corpuscles are all capable of imder- going similar changes, but with different degrees of facility, and, on this account, these changes are commonly seen in the primary or fugitive group only. These changes are of the nature of fmion, of granulation, and of fibrillation, and groups of each class may be shown in which these changes have occurred or are taking place. In Photographs 55, 56, 57, 58, 59, Plate XI., we have succeeded in isolating small mosaic groups of the invisible corpuscles, the corpuscles of which have passed into the spherical state. In Photograph 55 their outlines are tolerably distinct, but in Photograph 56 they have partially fused or coalesced, and in Photograph 57 still more completely. In Photograph 58 the masses formed by their coalescence have already commenced to granulate, and would shortly undergo separation into distinct granules, such as are depicted in Photograph 17, Plate IV., and Photograph 45, Plate IX. Photograph 60, Plate XI., gives an example of the direct conversion of the colourless discs into fibrin without passing- through the stage of granulation. This is a modified mode of action of the process of annulation.* Photograph 59, Plate XI., shows corpuscles of the secondary and tertiary groups in juxtaposition. It will be seen how mcap- able the former are of maintaining a distinct outline. It is corpuscles of this class which frequently become granulated, especially under the influence of cold, and thus give rise to the forms observed by Semmer. {Vide page 26.) These primary groups are often to be seen undergoing conversion into fibrin. The corpuscles of these groups are de facto fibrin, and the delicate fibres and layers which appear on glass slides are due, first, to the extension of these granu- * Vide Section on Fibrin formation. 58 Dr. Norris on Mammalian Blood. lations into fibres, or to amiiilation of the entire corpuscle, or secondly, to the spreading and laying down of these corpuscles into films. When blood is completely defibrinated these corpuscles and their granules entirely disappear, and can no longer be shown by any of my methods, though abundance of red corpuscles are still present from which the coloiu" might be discharged if the methods used could bring about this eflect. One of two things is, therefore, obvious, either coloui'less discs have been removed, or the discs which become colourless when my methods are employed. There can be no doubt that the former is the true view. The application ol a delicate photo-chemical test, such as is afforded us by photography, indubitably shows the existence of a regularly graduated series, from a colourless to a deep yellow disc. Of these, the colourless and the more faintly-tinted ones range themselves together on the unstable or fibrin side, and the more strongly-tinted on the stable or permanently corpuscular side ; in other words, the stability of the blood corpuscle is directly proportionate to its degree of cruorisation, and the flickering or diflused edged corpuscles mark the point at which the biconcave discs become converted into fibrin when the blood is shed. It must not, however, be supposed for one moment that we have in these discs to deal with a difference of colour alone. The corpuscles which constitute the "fugitive group" differ not only in colour but also in adhesiveness, in specific gravity, in liquidity, in their relation to stains, in their tendency to granulation, in their behaviour with re-agents, &c. Although, as before explanied, many of the corpuscles of the " fugitive group " possess some colour, yet on the whole the colourless disc may be taken as the type of their behaviour ; the red disc as the type of the behaviour of such as are more strongly-tinted than the diffused edged one. It will be simply necessary, therefore, to describe here the general properties of the colourless, or as I sometimes designate it, the prhiary disc. ■Dr. Noeris on Mmnmalian Blood. 59 Colour. — The primary discs are of the same tint as the ordinary white corpuscles when these have been rendered smooth and free fi'om granulation, i.e., that of the back- ground. The rosette masses, which they form by their adhesion to each other, are also of the same colour as similar masses of adhering white corpuscles. Adhesiceness. — They are more prone to coalesce with each other and with the white corpuscle, but show little tendency to associate themselves with the red. They have also a great disposition to adhere to air-bubbles and foreign matters introduced mto the blood, while the red discs have little or none. Sj)ecific Gravity.- — Like the white corpuscle, they are lighter than the red, and have a tendency constantly to rise to the surface of the blood, consequently the largest numbers are always seen to attach themselves to the upper glass, in preference to the lower, and especially if time is allowed them to rise. This, no doubt, has something to do with the huffy coat. Liquidity. — In this respect they differ much fi-om the red corpuscles. When in their natm'al state in the blood they are exceedingly liquid, and have no power to retain their form, being modified h-om moment to moment by ciuTents. It is not till they have formed adhesions to the glass, or have been hardened by re-agents, that their true form becomes obvious. So great is their natm'al liquidity, that they may be often seen to give off under the influence of capillarity, finger- like processes which lie between the more permanent corpuscles, vide Photographs 15 and 16, Plate IV. In its natural state in the blood there is reason to think that this corpuscle is far more plastic and yielding, but less elastic than the red corpuscle. Granulation. — The red corpuscles rarely undergo granula- tion, but these can scarcely be prevented doing so. In this respect they are like the ordinary white corpuscle, to which body they in fact assimilate in all their properties. These 60 Dr. Norris on Mammalian Blood. granules sometimes result from the breaking up of single corpuscles, and at others from the breaking up of groups or fused masses of them, vide Photographs 12, 17, 18, and 45, Plates III., IV., and IX., and Photograph 58, Plate XI. These are the bodies which M. Hayem has described as the hmnatoblasts of mammalian blood. The body, however, which in reality corresponds to the delicate corpuscles he has discovered in the blood of the ovipara, is the invisible colourless discr' Relation to Stains. — I have already stated in my former paper that these corpuscles when in the Liquor Sanguinis stain with carmine, and the red ones with aniline. I have found more recently that the colourless discs may be readily stained by a weak * Dr. Noel Gueneau de Miissy, the distinguislied honorary physician to the Hotel Dieu, has done me the great honour to reproduce nay work on the blood with remarkable exactness, and with a degree of lucidity which shows that he has taken considerable pains to acquaint himself thoroughly with my views. That he has much confidence in their general trustworthiness, may be inferred from the following passage : — " Cette accumulation d'inductions, d'observations, d'experiences si nombreuses et si ingenieusement variees, ne me parait guere Jpermettre de contester I'existence de ces nouveaux corpuscles ou disques incolores." There are, however, one or two points which seem to require from me some explanation. These refer to the relations which subsist between my work and that of M. Hayem, and are as follows : — " II combat I'opiuion de M. Wharton Jones, qui veut trouver dans les noyaux des leucocytes I'origin des hemoglobules. La theorie, dont il est le defenseur, et qui place cette origine dans les globules de la lymphe, avait ete deja entrevue ou soutenue par plusieurs physiologistes, entre autres par Kolliker et Huxley.* Elle est en opposition avec celle qui a ete proposee dans ces derniers temps par notre savant confrere M. Hayem, qui fait naitre les hematics de globules rudimentaires auxquels il donne le nom d'hematoblastes. Ces petits corps seraient, selon M. Norris, ceux qui ont ete decrits par Beale sous le nom de bioplustii et il les considere comme des gi'anulations produites par la rupture des disques incolores. Je me demande si M. Norris a bien compris la description de M. Hayem, qui ne me semble pas se prater a cette interpretation. " Sans doute, il y a entre les disques lymphoides de M. Norris et les hematoblastes de M. Hayem des differences essentielles de forme, de * Dr. de Mussy is in error here. Professor Huxley supports tlie views of "Wharton Jones. Dr. Norris 071 Mammalian Blood. 61 solution of aniline blue, in tliree-quarter per cent, solution of common salt. The blood should be allowed to run in by capillarity at one end of a large mica cover, and the stain should be so applied as to be drawn in after it. If the stain is not too strong it will tint the invisible corpuscles Avithout affecting the red ones.* volume, d'origine, mais la description qu'en donnent ces auteurs laisse voir aussi entre eux certaines analogies dont la plus saillante est le role que tous deux font jouer a ces corpuscles dans I'origine de la fibrine et la coagulation du sang. De nouvelles recherches me paraissent necessaires pour decider lequel de ces deux observateurs a le mieux vu, et pour ^clairer I'origine des hemoglobules, dont la theorie de M. Norris donne, iJ faut en convenir, une seduisante explication. " Quand bien meme les recherches de M. Hayem sur les hemato- blastes et sur leur role dans la genese des hematies recevraient la sanction des observations ulterieurs, I'existence des corpuscules incolores de M. Norris n'en serait pas ebranlee, leurs connexions avec la fibrine pourraient subsister." I desire, in the first place, to bear my most unreserved testimony to the originality and importance of M. Hayem's investigations. I regard them as the most profound researches which have been made in the blood for many years. Very little recognition has yet been accorded to M. Hayem by English physiologists, for the reason that very few have worked sufiiciently at the blood to enable them to form an opinion upon the merits of so obscure and difficult a research, and also because English Physiology is not yet educated up to " a morphological fibrin.'' Although M. Hayem and myself have laboured independently of each other, the main conclusions at which we have arrived are singularly in unison, naore particularly those which refer the formation of fibrin and the coagulation of the blood to such formed elements of the blood as are destined in the ordinary course of things to become the red corpuscles. Neither of us deny that the ordinary white corpuscle may contribute ill a small degree to fibrin formation, but we are both agreed that it is not the normal progenitor of the red disc. Up to this point our researches are mutually supporting. M. Hayem has very carefully described certain minute bodies long known to exist in mammahan blood, and has shown that these bodies are concerned in the formation of fibrin. He had already shown that the bodies which form fibrin in the ovipara were the early forms of the red blood corpuscle, and he has, therefore, naturally inferred that these variable elements in mammalian blood must be the early stages of the red blood disc. These bodies have some coloui', and are but a fraction of the size of the red disc, therefore the further assumption that they grow and attain more colour has to be made. On the other Vide section on staining. 62 Db. Norris on Mammalmn Blood. Objection III, By altering the refmctire index of the ' Liquor Samjuinis.-'- — The ground having been cleared by the previous discussion, we are now in a position to consider more profitably the objections which have been made to the use of a saturated solution of salt as a means of displaying the new corpuscles by altering the refractive index, I have already referred to the grave mistake made by my critic in attributing to me the use of salt in all my processes instead of in two only, (F«c?e page 42.) On this method my critic remarks — ^" As to the use of a saturated solution of chloride of sodium, I conclusively proved, by repeated experiments with the instruments used for the enumeration of the blood corpuscles, that a saturated solution of salt causes about one-third of the red corpuscles to discharge their haemoglobin, and to become clear, colom-less, ghost-like corpuscles." The fact that a certain number of the paler red discs disappeared in a concentrated saline solution was very well known to me, for when I decided to use a satm-ated solution hand, I find that the fugitive corpuscles, which are the same size as the red disc, are in various ways resolved into fibrin, and that in the process they often break up and become altered into the various minuter forms depicted bj^ M. Hayem in " The Archives of Physiology," pages 731 and 732. If this able investigator will trace these forms still further back, he will find that they are the disintegrations variously modified of partially coloured and colourless biconcave discs, and that it is these discs which are the true analogues of his oviparous hematoblasts. Vide section entitled " An Examination of the Researches of M. Hayem on the Development of Mammalian Blood." * If we place upon the tip of the finger a minute di'op of saturated solution of salt, and prick through it so that the blood may flow directly into the saline solution, the refractive power of the Liquor Sanguinis is modified, and it is found that if we run this mixture of salt and blood between glasses prepared according to the packing method before desoribed, we can then see the DiUlincs of the colourless discs, and the clear spaces which have hitherto been supposed to consist of Liquor Sanguinis only, are observed to teem with these discs. After a time specimens thus prepared become tinted with hsematiu, and this stains the edges of the colourless discs, and renders them still more apparent. Dr. Norris on 2Iammnlian Blood. 63 of salt, I first carefully went into the question of its effects upon the visible corpuscles. This solution has a certain limited power of dis- solving hagmoglobin, but it is an action that is soon satis- fied, for I have kept corpuscles in contact with it for a week in hermetically- sealed tubes without much change either in the colour of the corpuscles or of the solution. When blood is added to such a solution, there is no doubt that all the corpuscles give off a minute quantity of coloming matter. This action, while it would tend to render all the corpuscles a shade paler, also levels up the surrounding liquid to their colour, and so certain of the paler corpuscles disappear, not simply because they have lost colour, but also because the solution has gained it. Even when water has been added to blood, so as to render the corpuscles almost indistinguishable, we have only to get them out of the coloured serum to see that they have individually lost but little colour, and that the action has been mainly one of levelling up. Such ghost - like corpuscles placed again in uncoloured serum are still seen to possess a pale yellow tint. After I had satisfied myself of the existence of corpuscles that could not be seen, it did not seem to me a matter of much importance that a few pale visible corpuscles should be by this levelling-up action added to the invisible set. 1 adopted this method merely to prove what might a priori be expected, that the colourless discs would be brought into view by alteration of the refractive index of the liquid in which they lie, and also to preserve them, so that they might be stained, for after I had acquired the knowledge that these corpuscles were the fihrin factors, it occurred to me that, as neutral saline solutions prevented coagulation, they might do so by hindering physical changes in these corpuscles, and on examination I found this view to be correct. My critic proceeds : — " I therefore sought for other means of changing the refractive index of the serum, such as fixing the blood immediately it is shed, with a two per cent, solution of osmic acid, and by diluting the blood 64 Dk. Norris 0)1 ^[ammalian Blood. thus fixed by large quautities of distilled water. In such olu- tions in which the corpuscles have been preserved in eir normal condition, and the serum so diluted that its refracuve index is changed, I did not succeed in obtaining any trans- parent corpuscles, examine in thin layers, in the ordinary manner." On this I would remark that I should not expect to do much in the way of altering the refractive index by that method, because the blood liquid contains only f per cent, of chloride of sodiinn. It would not by any means produce such a difference in density as is effected by using a saturated solution of salt, and, therefore, if we did not bring into view the colourless discs by this method, we should have no right to infer that they did not exist. My critic considers that the osmic acid prevents the corpuscles losing their colour ; that, in fact, it fixes the colour, and therefore no colourless corpuscles are present, because none have been produced. I have repeated this experiment by pricking through a di'op of osmic acid on the tip of the finger, bringing the blood directly into contact with this fixing agency, mixing quickly and perfectly. I find that, if this mixture is run mider glasses prepared for the packing method, the coloui'less corpuscles are present, as usual, having, I think, a little more distinct- ness of outline. Having thus ascertained that the osmic acid so applied did not interfere with their presence, I proceeded in a second experiment to dihite with water, and here, too, I found colourless discs present in abundance. The failure of my critic to see them must probably have arisen from the fact that there was great j)aucity of corpuscles, with excess of liquid. If we run the whole of the preparation under a large mica cover, taking care that when it is laid down there is still ample space for liquid to filter off, we shall find, after a time, that the colourless discs will come into view in the free spaces between the red corpuscles. In about an hour they may be seen to greatest perfection, for by that time the layer of liquid above them has become sufficiently thin. Dk. Noeris on Mammalian Blood. 66 They may, however, be seen in some parts as soon as the preparation is made. The statement, therefore, that " if the refi-active index of the serum be changed by means which are conservative and not destructive of the integrity of the red corpuscles, the transparent or third corpuscle cannot be found by any of the ordinary methods of observation," I cannot accept as correct. In conclusion the principal reasons why the mvisihle colourless discs cannot be regarded as decolourised red discs may be thus briefly summarised :■ — 1. — In the methods of " impact," of " packing," and of "isolation," neither pressure, compression, nor violence are present, and if they were, they could not convert coloured into colourless discs. 2. — These colourless discs exist under conditions in which the decoloui'isation of red corpuscles cannot occur (colloid method. ) 3. — The colourless discs can be stained by a preparation (aniline blue) which contains that proportion of salt (f per cent.) affirmed bj^ others to be consistent with the retention of colourby the corpuscles. This preparation, when of the proper strength, does not stain the red corpuscles. 4. — They are present, as usual, when the blood is intro- duced directly fi-oin an artery into a f per cent, solution of salt fully saturated with haemoglobin. 5. — They have neither the physical nor chemical constitution of decolourised red discs, but of lijinph or gland corpuscles. 6. — The disintegrative changes which take place in these corpuscles give rise to the formation of fibrin in the blood, and the fibrin which is formed in the lymph has its origin in similar changes in the most advanced gland corpuscles. SECTION III. On the most Successful Methods of Staining the Corpuscles of the " Fugitive Gvoujk'" Difficulties of a very special character associate themselves with the attempt to bring out the colourless and the intermediate discs of the blood by means of stains. Had this not been so it is probable that these corpuscles would have been long since discovered during the study of the white blood corpuscles by these methods. The corpuscles of the "Fugitive Group" have a mode- rate affinity for certain stains, which diminishes in the ratio in which they assume colour. As the biconcave discs of the blood represent one continuous graduated series, without break, it is not to be expected that the staining will occur in any other than a graduated fashion, that is to say, there will be no sharp line of demarcation, on one side of which we may place discs which become stained, and on the other discs which do not stain at all ; but if we take the extremes, viz., on the one hand, the invisible corpuscle which takes the stain strongly, and on the other, the fully coloured red disc which refuses to take it at all, we can readily place the intermediately stained corpuscles in their proper position in the graduated series ; thus, if we use aniline blue, which is an excellent stain for this purpose, we shall find that the invisible corpuscles stain of a deep blue tint, while those corpuscles which have acquired a little haemoglobin assume a greenish tint, and those which have much, fail to stain at all. These differences in relation to the dye are found in the varying chemical composition of the corpuscles themselves. A body consisting mainly of paraglobin is undergoing gradual conversion into hsemoglobin, the former has an affinity for the stain, while the latter has none, hence the corpuscle stains in the inverse ratio of its degree of colour. Dk. Norris on Mammalian lUvod. 67 The green tint presented by some of the intermediate corpuscles is simply due to the combination of the bhie aniline, and the yellow hfemoglobin. The staining processes may be divided into the wet and the dry. In the former it is sought to stain the corpuscles as they lie in the Liquor Sanguinis, and in the latter after withdrawal fi-om this fluid. Each condition requires its own peculiar treatment. Wet Method. Staining ■ the corpuscles as they lie in the Liquor Sanguinis is rendered difficult by two circumstances, 1 The Liquor Sanguinis possesses a singular property of prevent- ing the staining of the fugitive corpuscles and also of discharging the colour from them after they have already become stained. This renders it necessary to use a strong staining fluid and sucli mechanical arrangements as will tend to bring the whole of the corpuscles into contact with the staining fluid. 2 Strong aniline blue solution breaks up the colourless discs into granules- If we take a drachm of a f per cent, solution of salt, and add to it 2 1 or 3 grains of aniline blue, dissolve and filter through flannel or lint, we have a fluid which will stain the corpuscles of the "Fugitive Group " — the invisible ones blue and the others blueish green, or greenish blue, according to their degree of colour. This preparation requires, however, to be used in a particular wa3^ Let a cover-glass be attached to the slide, and a little blood allowed to run under, sufficient to fill about a fourth part of the space, and then let the stain be introduced at the same spot. As it passes in it will sweep the mass of the corpuscles before it, but many of the yoimger corpuscles have already attached themselves to the slide and cover, and will be found to be deeply stained. When we try to iTse this stain in other ways, say by adding it to the blood, either by pricking the finger through a small drop of it, or by placing a drop of blood and a drop of staining- fluid in juxtaposition on the slide and allowing them to mix when the cover is lowered down upon them, we get quite a differ- ent state of things- — we see only large masses of stained granules. 68 Dr. Norris on Mammalian Blood. These owe their origin to the breaking up of the corpuscles, which we desire to stain and display. This is due partly to the fact that time had not been allowed them (as in the first case) to become attached to the glass, prior to their being attacked by a more limpid, that is a less colloidal liquid, than their natural plasma, and partly to the granulating action of the aniline. With a view to obviate this, staining fluids were made, con- taining different quantities of albumen, but it was found that although this substance prevented granulation it did not prevent the invisible corpuscles from adhering together in smooth masses, so that now we had corpuscular, instead of granular masses. It was clear that, for successful staining, something must be done to retain the corpuscles in the same non-adhesive state which they possess when in the blood current. Many substances were tried with this object, but the best of these proved to be ordinary white cane sugar. When this substance is used in proper quantity it completely holds in check the adhesiveness of all the coipuscles. Various ways suggest themselves for the use of this re-agent, but they are by no means equally good. The method which I advise, and which I have found to be most successful after many trials, is to reduce the sugar, in the first place, to an impalpable powder — taking a portion of this powder, place it on the tip of the finger, and prick through it, so that the blood may come in contact with the sugar immediately it leaves the vessel — ^blood may thus be converted into a syrup of any degree of consistency ; this blood syrup may be run under a cover glass at one side, and the saline aniline may be run under at the opposite side. When the blood syrup and the stain meet each other the invisible corpuscles will be seen to stain at the line of contact. In order that these corpuscles should be quickly stained, it appears to be necessary that they should come into contact with tJie staining fluid while it is at its full strength, or at least before it has become much diluted by the Liquor Sanguinis. It might be thought that to meet this difficulty it would be only Dk. Norris on McanmaUan Blood. 69 necessary to increase the strength ot the staining fluid. This is not so, for if we tinge the whole of the blood liquid deeply, the corpuscles stain, but they do not become properly visible, because they still lie in a liquid, having jpretty nearly, if not quite, the same colour as themselves. What is really wanted is that they should stain, and then leave the stained liquid for a lighter one ; besides, if we use the staining fluid too strong, there is an increasing liability to stain also the red corpuscles. The following is a very good method for getting a general idea of the varying degrees of staining power possessed by the corpuscles of the " Fugitive Group," and for shewing that the permanent group has little or no disposition to stain : run under a cover glass sufficient, f per cent., of salt solution to fill the space quite full, then place on the end of the finger a little very finely powered cane sugar, prick through it and squeeze the finger so that a small drop of blood may exude into the sugar, mix well with the needle and then add a drop of about the same volume of 10 per cent, aniline blue in J per cent, of salt solution, mix as before, and then transfer to one edge of the cover glass, and examine under the microscope the portion of blood which runs into the clear saline solution at the edge of the cover — saturated solution of cane sugar under the cover glass is an excellent variation of this experiment — in it the stained corpuscles retain their colour for a longer period. Glasses arranged as for the packing method are exceedingly useful to show the effects of staining. The blood may be mixed as usual with a small portion of sugar on the end of the finger, and to this may be added a small quantity of a f per cent, saline solution of aniline blue (10 per cent.), and after well mix- ing with the needle the preparation may be run under the cover glass. The colourless discs will first be seen in the unstained state in contrist with the deep blue surrounding, subsequently they will stain and become lost to view, and will afterwards re- appear as they become more deeply stained than the tinted Liquor Sanguinis in which they lie. This method has the advantage of proving that the corpuscles which become stained 70 De. Noekis on Mmnmalimi Blood. are the self-same corpuscles which show themselves as clear circular spaces when the packing method is employed. Mica covers may also he employed, time heiug allowed for the corpuscles to stain and pack. In all other respects we proceed as before. Dry Method. Whenever red blood corpuscles are allowed to dry upon the slide, e.g. after being picked out of the blood by the ' method of isolation,' or after being spread by means of a glass rod, it is impossible to subsequently add to them aqueous solutions of any kind, or even Liquor Sanguinis of fresh blood without causing solution of their hemoglobin. In such cases, therefore, it is necessary before applying any staining fluid to thoroughly fix the corpuscles by subjecting them, say for five minutes, to the vapours arising from a saturated solution of osmic acid. After this treatment the staining fluids may be used with impunity. All dry specimens fixed with osmic acid require that the strength of the aniline blue shall not be less than 2 per cent., and that it shall be applied for about two minutes. It is necessary to add that the coloiu- must not be washed off, bxit removed by capillarity as in the ' isolation method.' In no case must the blood be allowed to dry between the osmic acid and the application of the staining fluid, as this renders the specimen impermeable to liquid, and therefore incapable of absorbing the stain. Many of the corpuscles which stain would of course be visible in the absence of the staining, but others, i.e., the youngest ones, are neither visible or capable of being photo- graphed ; indeed, some of the corpiiscles which stain of a deep blue tint, and are therefore now exceedingly patent to the eye, are still incapable of being photographed, while others that liave stained nearly as much may be shown by pliotograi:)hy, owing to the fact that they possess a small amount of liiBmogloblin. We can, therefore, by this means, distinguish among the corpuscles which stain those which contain a little and those which are free from haemogoblin. This matter has been made the subject of special investigation. Section IY. An Examination of the Researches of M. Hay em on the Development of Mammalian Blood. In the year 1877 M. Hayem presented to the Academy of Sciences, and to the Society of Biology, a new research upon the blood, under the title of " Keclierches sur revolution des. Hematies dans le sang de I'homme et des vertebrates." This was subsequently published in detail in 1878, in the Archives of Physiology." It is the object of this paper to examine into the accuracy of these views, so far as they relate to mammalian blood, and also to point out the connections they have with my own published researches upon this question. In doing this the better plan would seem to be to begin by a careful statement of the views of M. Hayem, allowing him to give his own description of the bodies to which he specially draws attention, and subsequently to examine the methods. which he employs to display them, and finally to set forth the conclusions at which I have myself arrived after traversing the same ground. In the first place, this author affirms that there are in the blood of all vertebrate animals small elements which are neither white nor red corpuscles. These elements " may," he says, "be styled the germs of the red corpuscles, and are the youngest forms of them." He proposes to call these elements htrmatohlasts. It is freely admitted that these bodies are not new elements of the blood, and that the facts which are now adduced respecting them are not all new, and that many authors have given descriptions which may be considered with more or less, probability to refer to them. M. Hayem does not undertake to discuss the origin of these- elements, nor the different forms Avhicli they may assume * Archives de Physiologie, normale et Pathologique, publices par Messieurs. Brown Sequard, Charcot, Vulpian. 72 Dr. Noeris on Mammalian Blood. ■during the several periods of the evohition of then- being — nor the manner in which they are formed, nor the organs in which they arise. Taking the animal at birth, he devotes himself exclusively to the examination of its blood, in order to arrive at its exact anatomical constitution. It is important to remark that the bodies to which lie desires to draw attention are cisihle elements of the blood which may be seen as readily as the white and red corpuscles, without the addition of any re-agents or the adoption of any arrangements differing from those usually employed. The various methods suggested and explained are directed mainly to the preservation of these bodies for a lengthened period — to the maintenance of their true form, and to the retention of their colour. Thus, we are told, that in order to properly examine the hsematoblasts, it is absolutely requisite to take the blood as soon as and in the condition in which it leaves the vessels. The following is the method of procedure : — " Clean the glass-plates with alcohol or ether ; dry them carefully, then fix the cover-glass to the slide, by dropping at each corner of the former a spot of melted paraffin. A capillary space is thus obtained to receive the blood. " Place the slide upon the stage of the microscope, so tluut the elements of the blood may be observed immediately they penetrate by capillarity between the two glass plates. "It is necessary to employ considerable magnifying power, '■= and to cause the blood to drop upon the edge of the cover-glass at the very instant at which it is squeezed from the pulp of the finger. "As soon as the blood arrives at the capillary space, it rushes in with great velocity, and the various elements may be remarked quickly passing and rolling about. " At certain points, which are easily distinguished, the blood * Of! two or three — ob. 5 Nacbet. De. Nokkis on JSlammalian Blood. IS current is slower, and here the elements sought may be perceived. Thus, among the red and white corpuscles may be remarked other very small ones, which, at first sight, seem ta be very delicate and j^f'l^ '"^'^ corpuscles. "Almost as soon as seen they begin to change, throw out points, adhere to the glass, double up, grow pale, consequent upon the loss of the whole or a portion of their hasmoglobin,. and tend to join themselves to other corpuscles which they encounter, so as to form a mass. " Sometimes they arrest a passing red corpuscle, which adheres to a point of their circumference, whilst the cui'rent tends to drag it along, causing it to assume the shape of a pear. After some time the red corpuscle disengages itself and passes- on to coiatribute to the formation of rouleaux, and the small elements remain isolated, or form wreaths or groups with each other. " By this time they are much changed, and almost irrecog- nisable, but their presence has been now ascertained, and their transformations have been followed, and the fact established, that in addition to the red and white corpuscles, the blood con- tains some peculiar elements which change their appearance- very rapidly." In order to permit of these bodies being investigated with greater deliberation various methods are proposed, which are held to be calculated to delay or prevent the spontaneous changes to which they are so prone. Thus, the above experiment may be repeated at a tempera- ture of 0° Cent, or lower. All M. Hayem's experiments were made in the open air during the winter, so that everything was cooled doT^^l to or below the zero point. "It is easy, however, by the use of the cold stage, (as suggested by M. Hayem,) to repeat these experiments at ordinarj^ temperatures. M. Hayem has obtained the best results at -1" Cent., but good observations may be made at from 1° to l°-5 Cent. In this case the "red corpuscles 74 Dr. Norkis nn yiammalian Blood. •arrange themselves in roiileaux as at ordinary temperatures •and in the spaces between the rolls there may be seen small very delicate bodies, isolated or gathered into groups of two, three, four, or five, seldom more." " Tliese small bodies are remarkably clear in outline, although very delicate and thin ; the majority of them are obviously discoid, biconcave, and slightly colom-ed, others are •elongated, and have a kind of pedicle more or less long." Other methods have been employed, such as the use of osmic acid, of bichloride of mercury, and of spreading and and drying the blood. From the results obtained by these various methods the author feels himself able to give the following definitions of these bodies : — "Definition of so-called hmiiatohlastft (as seen at the tempera- ture of room.) — Very little corpuscles, resembling at first little red globules, very delicate and pale ; almo&t as soon as seen they begin to change, throw out spikes, adhere to the glass, double up, grow pale by loss of the whole or a portion of their haemoglobin, attach themselves to other corpuscles which they encounter to form a mass, remain isolated, cr form ^vl■eatlls or groups, and after a time fade away and become irrecogmsable. (As seen at the temperature of 1°:) — Small, very delicate bodies, in groups of two, three, four, or five, remarkably clear in outline, although very delicate and thin, the majority obviously discoid and biconcave, slightly coloured, others elongated, and liaving a kind of pedicle more or less long ; some show themselves as staffs, (batonettes,) or grains of rice. They are mostly elements seen edgeways, and have con- sequently greater refractive power, and are sm'roxinded by a deeper sliadow than those which are seen flat. They are per- fectly homogeneous, and have smooth surfaces, a colloid look, and nearly always a perceptible greenisli or yellowish tint, so that their substance resembles tliat of a red corpuscle, biit slightly coloured. The smallest, which have no granulations, are some- times colourless, but bear no resemblance to the white corpuscles. ' Dr. Noeris on Mammalian Blood. 75 In respect to size they are stated to have a diameter of 1*5 to 3-l,000ths of a millimetre /•- M. Hayem gives a fiu'ther description of these bodies, which is worthy of notice from the fact that it i-ecognises that they are composed of two distinct substances, and that they possess definite relations to fibrin formation. He says, " using a magnifying power of fi-om 500 to 800 diameters, it is easily seen that these bodies are angular, and that they present two parts, more or less clearly divided, the one being the circumference, which is greyish, or finely granulous, the other being the central part, which is corpus- cular, glossy, ovoid, and considerably refractive. Their first alteration consists of a kind of contraction, which renders them more brilliant and sparkling, and causes the exuding around them of a peculiar kind of matter." "The substance which is thus exuded by the hfematoblasts is ver}'' viscous, and this explains satisfactorily the formation of small masses. When first seen, the h^ematoblasts, which are united together, have the form of small angular grains, or little stars, and form frequently garlands, in which each grain can be picked out. Then these small corpuscles appear to attract each other strongly, and the viscous substance which surrounds them tends to form a commori mass, in which the constituent elements place themselves and become mixed. From the edge of this small mass a great number of fine prolongations may jut out."' I shall now endeavour in the light of my ovni researches to identify these corpuscles of Hayem, and to ascertain whether or not they are bodies with which I am acquamted, and if so, ask myself in what position I have already placed them in my scheme of the development of the blood, and also what histo- chemical properties I have ascribed to them. The formed elements of shed blood which can now be demonstrated to exist, in addition to the well-known red and * From about igj^f, to ■^■^ol. of an inch. 7G Dr. Norris on Mammalian Blood. white coi^puscles, and the fibrin, are : — I. — The invisible corpuscles or colourless discs. II. — The pale visible corpuscles which occupy an inter- mediate position, and fill up the gap between the former and the red disc. III. — These colourless and pale intermediate corpuscles in incipient states of granulation presenting the appearance of small groups of adhering granules. IV. — ^Masses formed by the coalescence of such granulating- corpuscles. V. — Isolated or separate granules, resulting from the complete breaking up of these corpuscles and the masses which they form. VI. — Minute granules due to the disintegration of the ordinary white corpuscles. Among these structures I have no difficulty in identifying the elements which M. Hayem has mistaken for the germs, of the red corpuscle. They are, without doubt, the modified forms of the younger discs, which I have described under the collective term of the " Fugitive Group," and they have consequently no more claim to be regarded as the germs of the red corpuscle than this derivation may confer upon them. The task of identifying these bodies has been rendered very easy, by the minute and accurate descriptions which M. Hayem has given of their size, colour, chemical and physical properties, and of the relations which they bear to fibrin. Before, however, proceeding further, it may perhaps be worth while to compare the general properties of these bodies with those which 1 have ascribed to the intermediate corpuscles of the "Fugitive ( Irroup." I. — They are described as possessing colour, but are nevertheless paler, that is, less highly coloured than the red corpuscles. II. — They exhibit adhesiveness, and by this means attach tlicmselves to the glass, and also form groups with each other. Dr. Noeeis on Mamwaliaii Blond. 77 III. — They are often described as possessing a liquid, lustrous, highly refractive appearance. IV. — They are very fragile, quickly undergo change, and suffer both in form and conspicuity. V. — They associate themselves in certain definite ways with jfibrin formation. VI. — They have certain well-marked relation to stains.* By reference to my previous papers, the reader will see that these are precisely the chemical and physical properties which my investigation has brought out in respect to the " Fugitive Group" of discs, some of which qualities are in fact implied in the designation. There is another property, on which I have laid particular stress, and which explains the varieties of form and size under which bodies possessing these properties appear in shed blood, this is the extreme tendency which the intermediate corpuscles of the "Fugitive Group " have to present themselves in modified and granulated forms. It is not, however, my inten- tion to rest on these general analogies, but to give actual examples of the disintegrations of the corpuscles of the "Fugitive Group," and to show that these are the bodies described by M. Hayem. The proof will consist, firstly, in showing that the corpuscles of this group break up into bodies, having the size, form, and colour of M. Hayem's hsematoblasts, and secondly, in demonstrating that if measures be taken which prevent the breaking up of these corpuscles no such bodies can be found in the blood, thus affording both positive and negative evidence of their fragmentary character. I shall then, in the first place, confine myself to tracking the visible corpuscles of the "Fugitive Group" through their various modifications and transformations, and, in order to do this methodically, I propose to fix the attention of the reader upon a group of corpuscles withdrawn from fresh blood, by the " method of isolation," in combination with the use of the vapour of osmic acid — vide Plate XII., Photograph 61. In this group Vidv Section on Stainiiii. 78 De. Norris on Mammalian Blood. there are to be found examples of every kind of blood disc, ranging from the colourless or invisible to the full red corpuscle . We have here, in a limited space, the means of studying some of the peculiarities of all these discs, and we observe that even here, preserved as they are by artificial means calculated to lix them at once in the condition in ^Yhich they happen to be at the moment they were withdi-a^vn fi-om the blood, great difi'er- ences exist. Thus we notice that the youngest of the series actually lie among the others very much as a simple liquid would do, sending in finger-like processes between the more stable corpuscles. From this we learn that the most primary corpuscles are not only as colourless as the Liquor Sanguinis, but that they are in the normal condition of the blood, nearly as liquid, and this, no doubt, fm-nishes another reason why they have not been earlier observed. When from these we pass to such as have a slight trace of colour, we note that with this accession of colour there is like- wise a corresponding power of retaining form ; but even these corpuscles are seen to be large in comparison with those still more colom-ed, owing to theu" greater disposition to spread out upon any surface with which they may come into contact. The most coloured have, therefore, the smallest diameter, because their disposition to do this is least. After blood is shed there appears to be also a disposition on the part of even the young coloured corpuscles to increase in size, probably from the imbibition of liquid, vide Photograph 89, Plate XIV. In groups such as those shown in Photograph 61, we have, therefore, liquidity, size, and colom- tc guide us in our conclusions as to the true position in point of age of the corpuscles which constitute them, and we are thus enabled, without difficulty, to place these corpuscles in their proper serial order, the one extreme of which is represented by a liquid colourless disc, and the other by a comparatively stable, highly coloured one. Between these two extremes lie the series of corpuscles, which, for con^■eniencc, I have termed " the Dr. Nokris on Mdmwalian Blood. 79 intermediates," and these must be also held to occupy an inter- mediate position in respect to the whole of their physical and chemical properties. Those which are more closely related to the invisible corpuscles will approximate to them in property, and those which are nearest the more highly coloured ones to them. I have stated before that the so-called hsmatoblasts of M. Hayem, so far fi-om bemg the germs of the red corpuscle, are, in reality, modifications and disintegrations of its younger forms, that, in fact, they are connected, not with the integrity and life of the corpuscle, but with the changes which accompany its dis- solution and disappearance as a corpuscular structure, changes concurrent with the shedding of the blood. It will now be my duty to show how the intermediate corpuscles give rise to these bodies, and to describe and illus- trate the various stages of the changes which these corpuscles undergo before thej^ reach that state of complete granulation which has been so frequently recognised in the blood, and from which point they have been so carefully and minutely described by M. Hayem. In every experiment where fresh blood is submitted to examination, either at ordinary temperatures, at blood heat, by means of the warm stage, or at the fi-eezing point or below, there appear, in addition to the red and white corpuscles, a number of variously coloured groups apparently formed of minute granules, and also isolated granules of the same kind as those which form the groups. Such isolated granules, and granule-groups, may be seen in Photographs 45, 64, 65, 68, 70, 71, 72, 75, 79, 80, 81, 87, 90, 91, 92, and 93. It is with the nature and origin of these granules and grantde groups (real and apparent,) that we have now to concern ourselves. M. Hayem's conception is that they are distinct bodies, which, being mutually adhesive, have become united with each other into little groups. This view is not, however, invariably correct, Im- I find that some of the smaller apparent .i^'roups, which arc seen when tlie blood is first inspected. 80 Dk. Noeeis on Mammalian Blood. are, iu reality, corpuscles in the act of undergoing granular disin- tegration. This is readily seen by removing from them the Liquor Sanguinis by the •method of raising the cover — (isolation.) These granulating corpuscles, having already adhered to the glass slide and Cover glass, are not removed with the bulk of the blood, and we are then able to ascertain clearly that they are in reality adhering corpuscles, which are undergomg two distinct forms of disintegration, which I propose to distin- guish as the rosette and granule foitn. In the first case bodies are produced having a white border, formed of smooth granules, and a centre, which has a greenish, aqueous, lustrous look, and we become aware at once, boih from their size and their general appearance, that we have under our eyes young blood discs in a modified state, and we are also aware, too, that we are witnessmg the manner in which some of the fi-ee granules seen in the blood are formed. By the use of the warm stage we appear to facilitate this change, for we find that the white borders of the specimens so prepared are more spiked and star-like. — Vide Photographs 67 and 69, Plate XII. As the green, lustrous centres photograph of a rather dark tint, we know that the change has occurred to corpuscles possessing some colour. On the other hand, when an ice-cold temperature is used, the action seems to be more confined to less advanced corpuscles, that is, to those possessing less colour, or the more primary ones. — Vide Photographs 62 and 63, Plate XTI., and their descriptions. The central, greenish-looking, lustrous part constitutes a sort of cent]'e or focus, fi-om which coloured fibres fi-equently radiate in every direction. Broken portions of these corpuscles appear to behave in the same manner as entire ones, the fragments also becoming surrounded by a white exudation border. — Vide Photograph 68, Plate XII., and description. As a consequence, these centres are very variable in size, some of them being produced by the green, lustrous J3r. Norris 1)11 Mammalian Blood, 81 portion of entire coi*piiscles ; others by that of several corpuscles fused into a mass ; and others by that of fragmentary portions only. It is by the changes which occur in the centres of these corpuscles and of their granules that the radiating kind of fibrin is produced. It must be borne in mind, however, that this is only one mode in which fibrin is formed. 1 have previously pointed out that the corpuscles of the glands and of the spleen exude, under certain circumstances, a content matter which is more colourless and liquid than their exterior. This material fi-equently arranges itself around the contracted pellicle which previously contained it, and thus a nucleated cell is simulated. At other times the content matter gets entirely free of the pellicle, and it then swims fi-eely about, presenting the appearance of a homogeneous liquid globule. This observation seems to afford the key to several similar changes which occur in connection with the " Fugitive Grroup" of discs. As these discs are now to be regarded in the light of gland discs in a further stage of development, it may reasonably be expected that they will continue to agree with these in at least some of their properties. The green lustrous corpuscles, which become the centres or foci of radiating fibres, appear to present us with the same phenomenon in a slightly modified form. When intact, they present themselves as lustrous, liquid, colloid, greenish corpuscles, having no perceptible difference of composition, giving the idea of perfect homogeneity of constitution ; but we soon find that we can track them through various changes, Avhich commence by the appearance at their edges or borders of a white matter, which appears to gradually exude, and to which the greenish matter which before covered the entire surface soon looks disproportionate in amount, and collects itself as a more or less irregular mass in the centre. — Vide Photograph 69, Plate XII. The material which has exuded soon begins to granulate, and the granules are fi-equently set free in the Liquor Sanguinis. Occasionally we succeed m obtaining these corpuscles in the most incipient stages of transformation into 82 Dr. Nokris on Mtiuniiiilinn Blood, the rosette form, and it will be observed that the corpuscles which undergo this metamorphosis are a little less coloured than those which we have spoken of as the diffused-edged corpuscles, some of which may be seen close by in the sarce photograph. — Vide Photograph QQ, Plate XII., and description. When a mass of granules undergoing this action lie together, the white matter which is exuded fuses, and forms a species of cement between them, so that the appearance is presented of dark granules, lying on or in a colourless sub- stratum. — Tide Plate XII., Photograph 72. This cement matter may gradually disappear, then granules of a darkish colour alone remain to represent the so-called haematoblasts. — Vide lower part of Photograph 68, Plate XII. So long as these rosette corpuscles, or their fragments, remain submerged in the Liquor Sanguinis, the white border is practically invisible, and the only part at all distinctly seen is the coloured central portion, which takes on angiilar and irregular shapes, owing to the changes which are occurring at the border. After a time these centres become further distorted and diminished by the passage from them of radiating processes. What is true of the corpuscles is also true of the granules produced by their disintegration. — Vide Photograph 86, Plate XIV. The central parts of these corpuscles, and of their granules, are the only portions which are visible so long as the serum is present, and they have been described by M. Hayem as " isolated, angular, colloid htematoblasts," These visible central parts are very variable in size, owing to the fact that they sometimes represent the green lustrous portions of several corpuscles which have become fused together, at other times the green portion of single isolated corpuscles, and at others isolated fragments of single corpuscles. The visible radiating fibres which arise from these bodies appear to have their origin, not from the exuded white matter, which might a jn-iori have been anticipated, but from the central, slightly-coloured material, and this accounts for these fibres being visible in the Liquor Sanguinis, for if they had been Pe. Norris un MdHinuilhm Blood, 83 formed from the invisible corpuscles, or from the invisible part or exudation border of the slightly-coloured ones, we could not reasonably expect to see them. For a further verification of the facts connected with the rosette corpuscles, and their fragments or granules, the reader is referred to Photographs m, 67, 68, 69, 72, Plate XII., and their descriptions. Photograph 79, Plate XIII., shows how the rosette corpus- cles and their granules adhere to the glass and become surrounded by red corpuscles which enclose and sixpport them, while the white borders of the isolated ones are spreading down and becoming lost to view, and simultaneously coloured fibres are proceeding from the central darker parts. This action represents the first step in the formation of radiating fibres from the rosette corpuscles. In Photograph 80, Plate XIII. the action has proceeded further, and the white borders of the rosettes have almost entirely disappeared leaving the central dark portions, which have become irregularly stellate and angular by fibres being dragged out of them (by corpuscles, which first adhere and then move on) to represent a group of so-called hfemato- blasts. In Photograph 81, Plate XIII., the coloured radiating fibres are still better displayed, the white borders of the rosettes are entirely dissipated, and the dark central portions are under- going •disintegration and conversion into fibres. In this specimen many red corpuscles are crossed by delicate fibres, which are cutting into their substance, and as the contraction of the fibre proceeds they will be completely cut into segments. I referred in my previous paper to the converse case to the one we have now been considering, in which instead of the white matter accumulating at the exterior of the corpuscles, it becomes gathered together into a single more or less globular mass in the centre. The coloured material being arranged as a zone or halo around it. — Vide Photograph 47, Plate IX.* It will be interesting to trace what becomes of this zone of coloured material, whether or not it spreads itself down, or •'' First Paper on Development of Mammalian Blood, y4 Dr. Norris 11)1 Maiinii/ilidn lihiad. becomes drawn out into fibres, as in the previous case. One thing these observations seem to render quite certain, namely, that like the lymph or gland corpuscles, these younger corpuscles of the blood are made up of two constituent elements, one of which is always darker or more coloured than the other, and this contrast increases ;jro rata with the assump- tion of colour by the young corpuscles, and we have afforded us, moreover, the most positive evidence that the material which has become coloured is located upon the exterior, while the colourless material normally occupies the interior, and thus its presence is entirely masked. It does not appear that these two substances are in chemical iinion, but that they are merely physically associated. If I might venture upon a hypothesis, I would suggest that the substance (paraglobulin ?) of which the lymph corpuscle is composed becomes gradually converted from without, inwards, by a series of changes into haemoglobin, the matter of the interior of the corpuscle being longer in undergoing this change. The corpuscles appear, however, to colour throughout their entire mass before they become highhj coloured upon their surface, and the best fibre-forming corpuscles are those young ones which have become coloured throughout ; for the colourless disc has less tendency to make fibre, and it is only the coloured part of the very young corpuscles and their granules which usually do this. For an example of the corpuscles most concerned in the formation of radiating fibres, vide Photograph 85, Plate XIV., and description. The changes which occur in these young mammal corpuscles strongly remind one of Briicke's division of the matter of the oviparous coi-puscle into Zooid and Oekoid. Of these two substances the white matter seems to undergo subsequent changes by thinning and spreading down into very delicate, invisible films, and this occurs both with the corpuscles and their granules, and, as a consequence, the white matter disappears almost simultaneously with the formation of fibres from the coloured portion. It seems, therefore, certain that Pk. Norris on ManDimliiin Blood. 85 both these substances are concerned in fibrin formation, though they proceed to their goal in a different fashion. The two sub- stances of which these corpuscles, or the granules which they yield, are composed, are not only distinct as far as appearance goes, but they have also a chemical distinction, wliich is shown by the difference of their behaviour with stains. The central part can be stained by aniline blue, while the border remains white. It is also quite easy to show that the substance which stains most readily is the one of which the radiating fibres are usually formed. Sometimes entire corpuscles which appear to be coloured throughout their mass become wholly resolved into fibres ; at other times fibres are drawn off from the periphery only. In this latter case the volume and size of the corpuscle is, of course, diminished proportionately to the extent to which this has occiuTed. M. Hayem has given drawings of such partially exhausted corpuscles, and has described them as haematoblasts. For examples of these two kinds of action, vide Photographs 78 and 82, Plate XIII. The perfect or unchanged primary corpuscle, having upon its surface only a comparatively thin layer of this delicate green substance, cannot stain very deeply, unless the dye is very intense. In all cases where the greenish exterior matter accumulates, or concentrates, the staining appears more decided, but this is, of course, only due to quantity or thickness. Coagulation appears therefore to be preceded by a separation of the chemical constituents of the corpuscles, and of the granules which result from their disintegration. White fibrin being produced by a re-arrangement of the matter of the primary or colourless discs, and the coloured fibrin from the exterior of the intermediate corpuscles, and in addition to this there seems to be satisfactory evidence that some portion at least of the interior matter of the inter- mediate corpuscles also becomes resolved into fibrin. I have before referred to the fact that certain of the partially- coloured corpuscles sometimes undergo changes somewhat 8() Dr. Norkis (jh Mioiniinliiin lilood. different to that which we have expressed under the designation of the rosette form, instead of becoming flattened, more extended, and presenting a white granular exterior, with coloured centre, the converse effect to this appears to take place, the centre of the corpuscle exhibiting itself as a white mass, while the coloured matter of the corpuscle remains extended around it, as a sort of halo, and after a time, this circular band or halo may disappear, leaving nothing but the central white mass. In fact, apart from breaking up into granules, the younger corpuscles appear to be capable of two kinds of modification. In the first place the white or colourless matter may burst or protrude through the coloured pellicle, which then gathers itself up into a central mass or nodule ; and in the second place the coloured pellicle may tall away from the colourless material, exposing it tn view, and allowing it to gather itself up into a globule. These colourless globular masses are of diverse sizes, according to the extent to which the colouring matter has pene- trated towards the centre of the corpuscle, and as the develop- ment of the latter proceeds they become smaller and smaller, and are at length obliterated altogether. — Compare Photograph 47, Plate IX., and Photograph 73, Plate XIII. and their descriptions. These white masses appear to have the power to aggregate closely with each other ; whether the corpuscles aggregate first and subsequently losing their exterior allow the central masses to come closer together, or whether the aggregation takes place after the loss of the exterior colouring matter, I am at present unable to say. It may be that the falling away of the exterior and the aggregation into masses takes place simultaneously. When however, the aggregation of these masses has occurred, it sometimes goes on to complete fusion, and the result is the formation of peculiar sheets which have been before observed by Osier of Montreal, and Max. Schultze. All the corpuscles, I think, are competent to the production of tliese sheets, and they sometimes result from the coalescence of corpviscles of various shades of colour. Dr. Noreis im yidmriuilian I>I(ki(I. 87 Most of the large white masses, seen in shed blood, pi'obably originate by aggregation, in this manner. — T7fZc Photo- graphs 73 and 74, Plate XIII., and their descriptions. The bodies -which contribute to the formation of the masses we have just described are much denser and larger in size than those which result from the breaking up of the white matter of the rosette corpuscles seen in Photograph 69, Plate XII. It now remains to describe the second form, in which the younger corpuscles constantly present themselves during the process of disintegration, which in contradistinction to the rosette, I have designated the [irannle-form . As in the case of the rosette form, all the corpuscles of the " Fugitive Group " are capable of undergoing this mode of change, but the primary corpuscle, nevertheless, is least of all liable to it, probably owing to its greater liquidity. The small groups of granules which have been supposed to be adhering hfematoblasts, are m reality in many cases nothing more than corpuscles of this kind, in process of granulation. This I have ascertained by removing the cover-glass, both at ordmary and at ice-cold temperatures, and viemng them in the absence of the obscuring influence of the Liquor Sanguinis. In many cases we are able to see corpuscles in various stages of disintegration, and can even count the number of granules into which they are about to become divided. In Photograph 70, Plate XII., a corpuscle may be seen in situ, which shows ten or eleven distinct granules, and a second one which is more imperfectly granulated, considerable portions of the corpuscle still remaining intact. When the posi- tions of the granules in relation to each other become disturbed, they still continue to adhere to each other by virtue of the matter exuded from their interior, and they frequently form themselves into circlets and beaded rolls, which have been described by M. Hayem under the name of ■s^Teaths, garlands, and chaplets. — Vide Photograph 71. Corpuscles of the kind which yield these granules may be seen unaffected on the same specimen, 88 Dr. Norris on MiDiwudum BlixuL In Photograph 71, Plate XII., the same conditions may- be seen in corpuscles a little more coloured, while the granules and the granular masses depicted in Photographs 62, 64, and 65, Plate XII., are the products of the disintegration of primary or colourless discs, and in the latter case the granules are giving rise to delicate colourless fibres. Photographs 90, 92, and 93, Plate XIV., also show the direct breaking up of corpuscles into granules. La Photographs 92 and 98, the various stages of the action are displayed, while in 90, the granular masses, or so-called hfematoblasts, are rei^resented. Photograph 91, Plate XIV., shows another mode in which coloured granules are frequently produced, by the segmentation and division of entire corpuscles. These fragmentary parts of corpuscles are often bi-concave in form, and have then the appearance of small bicon- cave discs. In Photograph 87, Plate XIV., is seen a mass of granules derived from the breaking up of comparatively colour- less discs. These are the so-called colourless hfematoblasts. They often coalesce so completely as to form mere skins, or plates, which frequently take on irregular angular shapes as seen in Photograph 88, Plate XIV. A further source of the so-called hfematoblasts is found in the fact that corpuscles of all degrees of advancement are constantly being cut into fragments by threads of fibrin, which pass over and lie upon them ; the fibre being fixed at its extremities cuts into the corpuscle when it undergoes its cus- tomary contraction. Such fragments can readily take on the bi-concave form. For examples of this process, vide Photographs 75, 76, and 81, Plate XIII. All these granules and fragments yielded by the corpuscles of the " Fugitive Group " are capable of being extended into fibres, and this appears to be the final form in which they become hardened. Photograph 75, Plate XIII., shows exceedingly well, young corpuscles breaking up into small granules, and the manner in which this granular debris becomes converted by extension into fine filaments of slightly coloured fibrin. Dk. Noreis on Mammalian Blood. 89 The cell Wcall and protoplasm of the ordinary white corpuscle also undergo granular disintegration, but the granules are easily distinguished from those yielded by the breaking up of the colourless discs, being smaller and more distinct, and never so far as I have been able to observe, entering into the formation of fibrin. Photograph 77, Plate XIII., represents the granules arising from the breaking up of the protoplasm of three white corpuscles. That we have in the foregoing investigations been dealing with the same bodies as M. Hayem is rendered obvious by the presence of the white exudation or cement matter, and by the fact that both researches show these bodies to result in fibruaous products. The changes which occur even in corpuscles having a con- siderable degree of colour are very imperfectly seen when the Liquor Sanguinis is present, and it is pretty certain that those which occur in the colourless discs, whether they be such as lead to the formation of rosettes, granule discs, granules, or of fibrinous networks, are entirely obscured. All this is altered when the Liquor Sanguinis is removed, for we are then able to follow the changes which occur in the most primary corpuscles, that is, in the discs which are free from haemoglobin. We then learn that the most profound analogies exist between the behaviour of the colomiess and the partially-coloured discs, which together constitute the "Fugitive Group;" that, in fact, they are capable of undergoing similar retrograde changes into rosettes, granule corpuscles, granules, and fibres, and also that masses of fused corpuscles undergo similar changes to single ones. — Tide Photographs 62, 63, 64, and 65, Plate XII., and descriptions. As before stated it not unfrequently happens that the frag- mentary portions of the corpuscles of the " Fugitive Group " are more or less bi-concave in form ; and this appears to have had considerable influence in causing M. Hayem to regard them as young red corpuscles. It has, however, not the least value in 90 Dr. Noeris on ^^((ninialian Blood. this connection, for the fragments of corpuscles will always take on this form, providing the Liquor Sanguinis is in the state favourable to its assumption and maintenance. It will be well to bear in mind that these fragments have all the mutability possessed by entire corpuscles, and can, therefore, present themselves as spheres or as biconcave discs, &c. These forms are entirely dependent upon physical condi- tions, and have nothing whatever to do with vitality. The fact that they can be produced by artificial means warrants this inference. — Vide Page 23 and Photograph 40, Plate VIII. It is here seen that perfect biconcavity exists in bodies as large as the red corpuscles, and also in the smaller granules. In addition to what has been said, it may also be stated that it is quite possible to break up experimentally the red biconcave discs by methods which preserve to the fragments their biconcave form. The foregoing constitutes the principal proofs I have to offer of the mode and source of origin of the so-called hsematoblasts, which it will be seen I hold to be entirely extra vascular and accidental formations, associated with the shedding of the blood. Methods of Preventing the Formation of the so-called h^matoblasts. I shall now ask the reader's attention to certain methods, which I have found either partially or entirely to prevent the formation of these bodies, by preserving intact the corpuscles of the " Fugitive Group." The principal agencies which I have employed for this purpose have consisted of modifications of the temperature and of the use of preservatives, such as osmic acid and cane sugar. Great stress is very properly laid by M. Hay em upon the importance of seeking for these bodies in blood which is perfectly fresli. A moment's reflection, however, will suffice to show us that neither blood which luis become reduced to the ordinary tempera ture of the atniosphere, nor that Avhich has pR. NoREis 0)1 Mamwalian Blood. 91 been subjected to the temperature of zero, or lower, can be regarded in the light of fresh blood. Both these conditions, it must be admitted, are exceedingly abnormal when we reflect that the natural temperature of the blood is about 98^° Fah. This illusion has arisen out of the circumstance of the well-knoAvn power of the freezing temperature to prevent coagulation and putrefaction ; but it by no means follows that intense cold is competent to prevent all the changes in corpuscles of which they are susceptible ; indeed, it is quite possible that it may induce or favour certain changes, and this really appears to be the case so far as granulation is concerned. It is also a well-recognised fact that the normal state of the white corpuscle is best preserved by maintaining the blood at its customary temperature. In perfect consistency with this fact, I find, too, that fewer so-called hsematoblasts present themselves in the specimens when this method of preserving the corpuscles has been adopted. There can be no doubt that cold holds in check those changes in the corpuscles which tend to resolve them or their granules into threads or fibres ; but this is mainly, if not entirely, due to the fact that it temporarily suspends the properties of fluidity, adhesiveness, and viscidity, which so remarkably characterise the younger blood corpuscles, and in the absence of which fibrillation does not appear to be possible, Thus, although cold favours granulation, it may entirely hold in check the process of coagulation by preventing the formation of fibrinous networks. When a maximum amount of solution of osmic acid is added to blood, the green granules are seen very distinctly ; they are almost always single and isolated, and seem larger than visual. They may readily be observed in the interspaces between the red coi-puscles, but are not as usual adherent to the glass, which may be known by the fact that they undergo constant Brunonian movements. 92 Dk. Norris on MaiiiutaUan Blood. Many of the red corpuscles are massed together, and there are sound reasons for thinking that in this case the invisible corpuscles form the cement matter which binds them to one another. When the cover-glass is removed, the red discs are seen to be much contracted, and they gradually become darker coloured when exposed to the air. Here and there may be seen small, smooth, green bodies, having a more circular outline than usual. These are the so-called hsmatoblasts. As might be expected under such conditions, very few traces of fibrin can be observed. From these observations I have felt justified in concluding that the maintenance of the normal temperature and the use of osmic acid are both means by which the nixmber of the so-called hsematoblasts can be greatly reduced ; but these agencies do not seem competent to entirely prevent their formation. During a series of experiments, conducted for the purpose of ascertaining the best method of preserving the corpuscles of the "Fugitive Group," in order that they might be submitted to the action of stains," it was found that nothing equalled ordinary white or loaf sugar, used in a certain manner. This does not lie so much in its power to preserve the normal forms of the corpuscles as in the great influence which it exerts over their adhesiveness, not only with each other, but with the foreign bodies with which they may come in contact. As this adhesiveness appears to be a necessary factor in the preliminary changes which the corpuscles undergo prior to the formation of fibrin, we can, by the use of varying quantities of sugar, so control these changes as to render it possible to track the whole series of corpuscular modifications and degenera- tions which eventuate in fibrin formation. The method of adding the sugar to the blood is of the greatest moment, for in no case must water be introduced. The plan I adopt is to reduce the sugar to an exceedingly I'ide Section on iStaiuiiiL'. Dr. Norris on Mammalian Blood. 93 fine powder. A portion of this powder is then placed upon the end of the finger, and the prick is made through it, so that when the finger is squeezed the blood may come into immediate contact with the sugar and dissolve it. The liquid of the blood itself is thus made the solvent of the sugar. After thoroughly mixing with the point of the needle, the blood is allowed to flow, by capillarity, beneath the cover-glass in the ordinary way. I shall now endeavour to give an idea of the influence of different proportions of sugar used in the manner indicated. If we add a little only, say one part of sugar to three parts of blood, by volume, the adhesiveness of the red corpuscles, on which the formation of rouleaux depends, is not overcome, con- sequently these form nearly as usual. Certain white granules are also present, which are indicative of changes in some of the earlier forms of the corpuscles of the " Fugitive Group." Little or no fibrin is, however, to be seen between the rolls. Delicate trail fibres may, it is true, be seen where the liquid has been driven back by an extension of the area of air bubbles. "When the cover, however, is removed, we find that the primary corpuscles are laid down beneath the red ones, and on sub- sequently washing the slide, (after the method of Eanvier,) layers of fibrin are observed, freely perforated with small holes, which look like accumulating granules, also masses of granules, with white corpuscles adhering to them. If, on the other hand, we mix together in the same manner equal portions of blood and sugar, we prevent the formation of rouleaux, and also the formation of fibrin, but we do not altogether prevent the occurrence of the granular disintegrations of the corpuscles of the " Fugitive Group." Smooth, sheet-like bodies are formed, evidently by the fusion of corpuscles, of slightly different shades of colour. When these sheets are seen, after the removal of the cover and washing with water, they are decidedly fibrinous in character, their corpuscular origin being no longer apparent. In such specimens fibrin does not exist in any other form than in these sheets. 94 Dr. Norris on Mammalian Blood. Of the so-called bsematoblasts, those containing colour alone remain, the colourless ones being absent. In the third case, much sugar being added to the blood, three parts of sugar to one of blood, the formation of rouleaux is entirely prevented. The colourless granulations are absent, and there is no formation of fibrin, for none can be seen, even after the removal of the cover, for no traces of either fibrin or corpuscles remain on the cover or slide. In these preparations there is also an entire absence of the so-called haematoblasts, both coloured and uncoloured, and as, at the same time, all the corpuscles of the " Fugitive Group '^ are preserved, I feel justified in holding the view that the sugar has entirely prevented these accidental products being formed. In the face of all this positive and negative evidence, we are inevitably impelled to the conclusion that the green lustrous granules and bodies which M. Hayem has termed haematoblasts are nothing more than accidental products derived from the breaking up of the corpuscles of the " Fugitive Group," nameh/^ of those which have obtained some colour, but under certain circumstances it is clear that the primary discs also contribute a certain proportion of granules, but this can only be shown by removing the Liquor Sanguinis ; hence none of the granules seen by M. Hayem were of this variety. All the granules, coloured and uncoloured, are capable of being converted into fibres, and, therefore, take their share in fibrin formation, and in the coagulation of the blood. It is a curious circumstance that it does not seem to have suggested itself to M. Hayem to enquire as to whether these minute and confessedly variable and irregular elements of the blood might not be due to the disintegration of some of the visible paler blood discs. It appears to me unfortunate that an exhaustive investi- gation of this aspect of the subject should not have been made before venturing on a conclusion of such importance and magnitude as is contained in the statement, " These bodies are the germs of the red corpuscles, and I therefore propose Dr. Norris on Mamnuilian Blood. 95 to call them liaBmatoblasts." It is clear that their only claim to be so regarded and designated must rest upon their being proved to give rise to the red corpuscles, and this, of course, involves the demonstration that, beyond all reasonable doubt, they develop gradually and regularly into these bodies. There are only two circumstances which can possibly justify us in concluding that one body is the germ of another— either we must observe, without break, the entire process of evolution and growth, or we must be able to place the several elements which we find in appropriate numbers in such serial order that the transitions from one to the other shall be easy and obvious. An attempt to do the latter, it is true, has been made by M. Hayem, but it is to my mind very unsatisfactory. In order that my readers may possess the opportunity of forming their own judgment as to its value and conclusiveness, I have introduced the diagram which M. Hayem furnishes and on which he relies. It may be seen on Plate, XIV. Fig.G, and its description is as follows : — Elements seen in the blood, prepared by the aid of liquid A '^ (a) adult red globules, (b) young globules more or less deformed, intermediate forms between the hasmatoblasts and the adult red globules. It will be observed, in the first place, that the specimens brought together are selected from preparations which have been subjected to the action of a re-agent, and secondly, that they do not by any means fulfil the canon of easy and obvious transi- tion which has just been laid down. It will be noted that they are very irregular in form and size, and in state, as to corruga- tion or smoothness, and that in no case could we pass with any feeling of security from one element to the next succeeding it in order, and also that they seem to grow smaller where we might naturally expect a graduated enlargement from first to last. These elements are all represented as coloured, whereas we know that many of the so-called h^ematoblasts, or granules * Distilled Water 200, Sodium Chlor de 1, Soda Sulph 5, Mercuric Bichloride O.CO 96 Dr. Norris on Mammalian Blood, seen in the blood, have scarcely any colour, even when an ice- cold temperature is employed, under which condition the Liquor Sanguinis often remains very colourless. M. Hayem, being unacquainted with the fact that colourless discs existed in the blood, regarded the white granules which he saw as decolourised hasmatoblasts, but this we know not to be the case, for we can trace their production to the breaking up of discs which have certainly never possessed colour. M. Hayem' s view of the mode of the development of the blood labours under the disadvantage of being retro- gressive in its character, and inconsistent with much valuable knowledge, which has been acquired in connection with this subject in the past by the laborious researches, both physiological and pathological, which have been made into the functions of the spleen and the lymphatics ; it is moreover not in accordance with the analogies which he has himself made out to be true of oviparous blood, in which we see fully formed, nucleated, colour- less corpiiscles, gradually obtaining colour. All difficulty, how- ever, disappears, when we come to know the true origin of the bodies to which M. Hayem has devoted so much attention, and recognise them as portions or fragments only of the younger discs of the blood. We are not then at all surprised to find that they possess different physical, physiological, and chemical characteristics to the fully developed red corpuscle, for this I have abeady shown to be the casewith the discs of the "Fugitive Group," and what is true of these bodies as a whole (in these respects) must also be true of their parts. I desire it to be distinctly understood that my observations on the work of M. Hayem are entirely restricted to the views he has published on mammalian blood, and have no reference whatever to his valuable research on the blood of the ovipara, which I regard as a most important contribution to our know- ledge, and a powerful corroboration of the correctness of my own discoveries and views in relation to mammalian blood ; for if the nucleated red corpuscle of the ovipara is preceded in the order of development by a nucleated Dk. Nobris on Mammalian Blood. 97 colourless corpuscle, it is exceedingly probable that the non- nucleated red disc of the mammal will be preceded by a non- nucleated colourless disc. M. Hayem has shown the former to be the case in oviparous blood, and I have shown it be so in mammalian blood, but as both these corpuscles have an extra- vascular origin, it is not legitimate in either case to term them JicemMoblasts. They represent simply a stage in the development of the blood corpuscle, neither its beginning nor its end ; and in either case they are only entitled to be regarded as the colourless stage of the blood corpuscle ; the distinctive difference being that peculiar to each kind of blood, viz. : the one possesses a nucleus and the other does not. The reader may become acquainted with the relation which these two bodies bear to each other by a careful study and comparison of Photographs 61, Plate XII., and 83 and 84, Plate XIII. While, then, Iregard the description of these granular bodies, as given by M. Hayem, as accm^ate and reliable, I differ entirely from him in his fmidamental conclusions as to the role they play in the development of mammalian blood. To make this difference distinct and clear, it may, perhaps, not be out of place to briefly recapitulate the view of the development of the blood, which I consider to be supported and justified by my own researches. The reader may advantageously contrast Diagram 6, Plate XIV., given by M. Hayem, as illustrative of the mode of develop- ment of the blood, with the series of photographs of lymph and blood corpuscles, ranging in order from 94 to 100. It must be premised that according to my view the function of the blood- glands is not to produce a body like the ordinary white blood corpuscle ; but on the contrary a thickish disc-like body of about the same diameter as the blood-disc, which, in the coui'se of its development, loses a delicate external layer, while its nuclear portion, which is very little less than the whole body was originally, undergoes conversion into a colourless bi-concave disc, and takes its place in the blood as it^ colourless disc. The lymph corpuscles, while in the glands may be seen to be under- 98 Dr. Norris on Mammalian Blood. going these changes, as is shown in Photographs 94, 95, and 96.* It will be readily seen that some of these bodies are already beautifully bi-concave, while others are still in the process of transition. On account of the necessity to get these structures in the absolutely fresh state they have been obtained from animals just killed, and are a little less than they would be if got from the human species. In all other respects they compare well with the colourless discs of human blood, seen in Photo- graph 97, and these in their turn form an easy transition to the slightly tinted ones lying among the red ones, in Photographs 98 and 99, and the latter easily bridge the gap to Photograph 100, which represents the fully coloured-biconcave disc, the con- cavities of which have been slightly exaggerated by the osmic acid. The red discs in 98 and 99 are also a little darker than they should be, and somewhat altered from the normal owing to the use of concentrated vapour of osmic acid to assist in the preservation of the bi-concave form of the younger discs in the specimen. It will be seen, therefore, that after protracted investigation of the subject in its various bearings, I still hold to the view of the development of the blood, set forth in my first paper, which is briefly this — 1. — Suitable methods of examination will reveal in mam- malian blood the existence of numerous corpuscles (about one to sixty red ones,) which are incapable of being detected by the use of the microscope alone, not because of their minuteness, for they have the same diameter as the red discs, but because they possess the same refractive index, and the same coloui" as the Liquor Sanguinis, in which they are submerged. When brought into view, and carefully examined, they are found to be colourless bi-concave discs, and between these and the red bi-concave discs the existence of other bi-concave discs, possessing every gradation of tint, can be detected not only by the eye, but more conclusively by the aid of the most delicate photo-chemical tests. * Vide the Author's Paper " On the Products of the Blood Glands." Dr. Norris on Mammalian Blood. 99 2. — When the morphological elements of the blood- glands are examined, with the same precautions for their preservation as are found necessary with the blood corpuscles, they prove to be discs in various stages of development; the most advanced of which are excessively dehcate, scarcely visible discs, of the same size and smoothness as the red blood discs, ajid of a bi-concave form, 3. — These bodies are poured into the blood, in large num- bers at the subclavian and splenic veins, and are henceforth completely lost to view till they re-appear by gaining an amount of colour, slightly greater than that of the Liquor Sanguinis, when they become recognisable as the palest order of red corpuscles. During their colourless stage they are the invisible discs of the blood, and the analogue of the nucleated colourless oval cor- puscles (so-called ha3matoblasts), of the ovipara, the nuclei of which alone are frequently the only parts that can be seen so long as they remain submerged in their own proper liquid. In both cases these corpuscles, as yet free from hsemoglobin, form the missing link between the advanced lymphatic and splenic and the red blood corpuscles. SECTION V. On the Morphological Products of the Blood Glands. The discovery in the blood of mammalia of large nmnbers of biconcave discs possessing the same colour and refractive index as the Liquor Sanguinis, and which therefore lie hidden in this liquid, together with coi-puscles possessing every intermediate shade of tint between these and the red discs, has rendered it desii-able (with a view of ascertaining definitely the source of these discs) to investigate thoroughly the nature of the morpho- logical products yielded by the blood-glands, e.^.,the lymphatics, spleen, thymus, thyroid, supra-renal capsules, &c. A limited devotion to the subject sufficed to show that this part of histology had been far fe'om exhaustively studied, and that to this fact alone was largely attributable our profound ignorance concerning the mode of development of the blood, and the natm*e of its diseased conditions. No advance worthy of the name has been made in this aspect of the subject since the days of Hewson, (1774.) Its literature is of the most meagre character, and the conclusions arrived at are conflicting and uncertain. Keflecting this general ignorance and slavishly copyhig each other, our text books, with few exceptions to be presently noticed, concur in regarding the lymph corpuscles as " identical with the white corpuscles of the blood." In the earlier part of this work (p. 25) I referred briefly to this question, and pointed out that Gulliver, Gray, and others did not concur in this view, and myself gave a number of reasons which appeared to me conclusive against it. It is but justice to the dead, and to the Scotch school of physiology, to state that Dk. Noreis on Mammalian Blood. 101 Professor Hughes Bennett entertained far more accurate viewa on this subject than many of his contemporaries. After speaking of the molecular basis of the chyle, described by Gulliver, he says : " Floating amongst these (oil globules) we observe granular and globular bodies about the 1 -4000th of an inch in diameter, which on the addition of acetic acid exhibit a thicker margin than they did before. In chyle taken from the thoracic duct there are also biconcave flattened discs, exactly resembling the coloured blood corpuscles in size and form, but destitute of colour. Between these two kinds of corpuscles (the granular bodies about 1 -4000th of an inch in diameter and the colourless biconcave discs) all kinds of intermediate stages may be observed, so that there can be little doubt that the former become flattened and are changed into the latter. They are in fact embryo blood corpuscles which become coloured in the lungsJ"* Again speaking of the lymphatic glands, he says: "On cutting into these glands shortly after digestion, and examining microscopically the fluid they contain, it may be seen that a molecular fluid (first described by Gulliver) is more or less crowded with naked nuclei which resist the action of acetic acid. On repeating the observation on fluid taken fi'om the thoracic duct the same thing is noticeable, only several of the nuclei are now flattened, and in every point, except colour, closely resemble the red blood corpuscles.'" \ It is quite obvious from these passages that Professor Bennett did not, as so many have done, confound the true lymph corpuscles (which he regarded in their most developed form as colourless biconcave nuclei) with the ordinary white coi-puscles of the blood with which, in his investigations of Leukh^mia, he had become so familiar. In the thoracic duct, side by side with these colourless biconcave disc-shaped nuclei, destined to become coloured after they had entered the blood, Bennett recognised also the presence * Text Book of Physiology, page 60. t Test Book of Physiology, page 208. 102 De. Norris 071 jSJ mmnaUan Blood. of bodies which he regarded as the equivalents of the ordinary white corpuscle. We shall see in the sequel how closely these views of Bennett approximate to the truth. The illustrious German pathologist, Professor Virchow, describes lymph corpuscles taken from the interior of the follicles of the lymphatic glands as consisting of two kinds. 1st. Free nuclei with and without nucleoli. 2nd. Cells with smaller and larger nuclei which are closely invested by the cell-wall. In common with other investigators, he does not find in these glands any bodies corresponding to the multi- imclear white blood corpuscles, and I am not aware that he has referred to the condition of these elements as they exist at the upper part of the thoracic duct, but, inasmuch as he states "that of the minute elements contained in the follicles some appear to become separated and afterwards to mingle with the blood as colourless blood or lymph corpuscles," it is apparent that he considers some of these elements develop into the white corpuscle of the blood ; on the other hand, Virchow ofiers no opinion as to the origin of the red corpuscles, but, on the contrary, says, "the whole history of the red corpuscles is still invested with a mysterious obscurity, inasmuch as no positive information has, even at the present time, been obtained with regard to the origin of these elements."* The following quotation shows, however, that he leans towards the view first promulgated by Hewson, viz.,i that they are in some way or other the products of the lymphatic glands and spleen. " A good many years elapsed (after 1845) during which I found myself pretty nearly alone in my views. It has only been by degrees, and indeed, as I am sorry to be obliged to confess, in consequence rather of physiological than pathological considerations, that people have come round to these ideas of mine, and only gradually have then- minds proved accessible to the notion that in the ordinary course of things the lymphatic * Virchow's Cellular Pathology, p. 223. t P- 172 ibid. Dk. Noeris on Mammalian Blood. 103 glands and spleen are really immediately concerned in the pro- duction of the formed elements of the blood ; and that in parti- cular the corpuscular constituents of this fluid are really descendants of the cellular bodies of the lymphatic glands and spleen which have been set free in their interior, and conveyed into the current of the blood." If from these writers, so justly entitled to a primary hearing , on these questions, we turn to later investigators, we do not find the area of our knowledge to be materially enlarged; for, while much investigation has taken place in connection with the white blood corpuscle, it relates chiefly to its anatomical constitution, to those physiological attributes known as ameboid motion, and to the facts connected with its passage through the vessel walls. Nothing further has been done to indicate the connection which the products of the blood glands bear to the red and white corpuscles of the blood. At the very outset of this research, and in the face of the reservations of the eminent observers I have quoted, we are met in all directions with the stereotyped statement that " the products of the blood-gkmds are identical with the ivhite corpuscles of the blood,'' a statement at once incorrect and confusing, because it leads to the erroneous opinion that the function of the blood-glands is simply to originate the white corpuscles of the blood £i-om which (to borrow the words of Prof. Huxley) the red corpuscles are " in some way or other " produced.* In the first place, the white blood corpuscles are not even identical with each other, either in size, in chemical constitution, in histological character, or even in physical appearance. They so differ in size that, while some are not more than 5-20000th of an inch, others attain to a diameter of 10-20000th of an inch, ^ome can be made to exliibit an uni-nuclear appearance only, while others may display from two to five nuclei. Both of these varieties may lie in weak aniline blue staining fluid for hourst * Elementary Physiology, page 62. t In one test case for thirty hours. 104: Dr. Noeris on Mammalian Blood. without their nuclei becoming stained ; but if their pellicular cell covering be ruptured mechanically or otherwise, which can readily be done at will, the freed or exposed nuclei (as the case may be) at once become deeply stained. Other forms appear on the contrary to be already in the condition of free nuclei, for they take the stain throughout their substance the moment it is- added to the blood. They are obviously devoid of the protective covering which the former class possess. The utmost that can be with accuracy affirmed is, that some of the white blood corpuscles have a close resemblance to, and an affinity with the true lymph corpuscle, i.e., with the body which it is the special function of the blood-glands to produce, Avhile others, the multi-nuclear variety, bear a resemblance to certain bodies which are not (in the state at least in which they now exist) the normal products of the blood-glands, but yet may be found in the thoracic duct and the larger lymphatics. In a word, if we could abstract from the blood its red corpuscles, there would still remain in it colourless discs and uni-nuclear and multi-nuclear white corpuscles. The prototypes of the two former can be found in the blood-glands, but of the latter only in the thoracic duct and the larger lymphatics. The true relations however which subsist among these bodies will become more and more obvious as we proceed. When we cut into the substance of a fi-esh lymphatic gland or of the spleen, and take out on the point of a knife a portion of the lymph which flows spontaneously into the bottom of the incision, we find that we have present two kinds or conditions of corpuscles, one of which is readily seen, being distinct and corrugated, the other smoother, fainter, and far less distinctly visible. The former kind have a diameter of from 4 to 5-20000th of an inch, and are the bodies in the lymph which have usually been described as free nuclei. The latter, if observed at all, which is doubtful, have not hitherto attracted any attention, probably owing to the great variety of appearances they present, which is most perplexing till the key to their true nature has been discovered. Dr, Norris on Mammalian Blood. 105 At this stage of the inquiry I must ask permission to anticipate somewhat the proof which I have to bring forward, so far as designating these two kinds of corpuscles by the terms primary and advanced, as it will enable me to present the facts in a clearer and more intelligible form. It is my intention to show that these two kinds of corpuscles represent extreme conditions in the development of one and the same body, and that the same terms permanent and fugitive are as applicable to them as to the corpuscles of the blood, but with the difference that in this case the youngest or most primary is the most stable, whilst the more advanced ones constitute the fugitive class. It will be seen that this is precisely the converse of the blood. Again, between these extremes of the lymph corpuscle as with the blood it is possible to detect every intermediate kind, and we are consequently compelled to conclude that we have also in these corpuscles to deal with bodies which are under- going a regular and gradual development, which, as it proceeds, renders them more plastic, smoother, whiter, less visible and more amenable to change when the lymph is shed. Here in fact as in the blood we are presented not with one body but with a graduated series, the least perfect of which are the bodies best seen and commonly described as the lymph corpuscle, while the more advanced ones approximate with exceeding closeness to the invisible discs of the blood, in size, form, appearance, physical and chemical constitution, and more par- ticularly in that amenability to change from their usual corpus- cular condition into the forms and conditions commonly recognized as fibrin. "^^ As a consequence of this extreme instability, the advanced lymph coi-puscles are rarely seen in shed lymph in their true and normal form, but generally in every conceivable " state of degeneration and breakdown, and it is only after we have laid hold of this fact and have adopted means for their preservation that we can form any conception of their real nature. * Vide Section on Fibrin Formation. 108 Dr. Norris on 'MdmmaUan Blood. In Photograph 101, Plate XV., the reader will find a representation of the body found in the follicles of the glands, which is commonly regarded as the lymph corpuscle, a d usually conceived to be a simple nucleus. It is, however, as I have said elsewhere, to be regarded as a conjugated , thick, disc-shaped body, having an average diameter of from 4 to 5 •20000th of an inch. This is the body whicli I propose to distinguish by the name of the primar;/ hpaph corpuscle. It has comparatively little liability to change, is rather rigid than plastic, and while submerged in the liquor lymphae has very little tendency to flatten and spread itself down upon the glass slide. It neither stains or swells undei the influence of saline aniline blue*. Photograph 102, Plate XV., shows such corpuscles obtained from a fresh lymphatic gland of a pig. It will be seen that the puckerings or corruga- tions have disappeared, and that the corpuscles have at the same time increased in diameter, and are, therefore, more disc-shaped. Some of them are of mucli greater diameter than others. These latter are the more advanced ones, they have attached themselves to the glass, and are spreading down upon it. In Photograph 103, plate XV., we have an illustration of the appearances presented by lymph corpuscles taken from the same gland after the liquor lymphge has been withdrawn from them by the "method of isolation" as practised with the blood. i The difference between the two conditions of the corpuscle is here made more manifest. The primary ones photograph with a strong dark edge, and have a tolerably regular outline, and are all of about the same size, while the advanced ones are without a distinct outline, and are modified in shape by being subjected to pressure by the more rigid primary corpuscles. It will' be seen further that when they are unsupported by these tliey have a marked tendency to spread themselves out upon the slide, to become more irregular in outline, and more confused Half per cent, aniline in | per cent, salt solution. \ Vide page 7, Section I. Dr. Norris on M/unnialian liluod. 107 and granular in character. Between these corpuscles there is also a great difference in colour, the advanced ones beinj white or coloui'less, while the primary ones have a greenish tint, which, like yellow or red tints, photographs of a dark colour. This colouring matter, whatever it may turn out to be, must not be confounded with hfemoglobin, as it does not yield the absorption bands of tliis substance. In Photograph 104, Plate XY., we have a good example of the action of spreading or extension, to which the more^ advanced lymph corpuscles are liable. They appear first to adhere to, and then to spread themselves out upon the glass slide. Any granules that may be present are driven outwards by the spreading action, and collect mainly at the circumference of the extended corpuscles, hence they are ofteii seen to be disposed in the form of arcs, or portions of largo circles. These curves map out and indicate the degree of extension which the corpuscles have undergone. Photograph 105, Plate XV., shows an excessive action of the kind which came on rapidly. The primary corpuscles, too, in this case, liave spread out into larger discs, while the advanced ones are^ spread enormously, as indicated by the granular boundaries. In Photograph 106, Plate XV., we have an illustration of this . peculiar action in its first stages. None of the above specimens are interfered with by reagents. In Photograph 107, Plate XV., is shown a specimen of lymj)h which was diluted with fresh blister fluid. The advanced corpuscles have spread excessively, and the primary ones have been converted into smooth discs of about the same size as the red blood discs. Photograph 108, Plate XV., illustrates a case in which this spreading action, peculiar to the advanced lymph corpuscle, has been restrained by diluting with a five per cent, solution of salt. The corpuscular character of the advanced coi'puscle is now better seen, yet the difference between it and the primary one is still sufficiently obvious. Phoiograph 109, Plate XV., is a specimen of gland coi-puscles from the pig, prepared by diluting the lymph with an equal quantity of f per cent, of salt solution. 108 Dr. Nobeis on Mammalum Blood. and then preserving and diffusing simultaneously by blowing hard upon it with an indiarubber syringe, till quite dry. The differences between the primary and advanced lymph corpuscles are not as well seen in this specimen as in 103, but it will be observed that the ground work is covered with granules, some of which are dark, and others white, which are probably the debris of both kinds of corpuscles. Photograph 110, Plate XV., also shows the existence of these extreme kinds of corpuscles in lymph obtained from the thyroid gland of the calf. The corpuscles which are intermediate can also be well seen in this example, and are detectable by their varying degree of colour and tendency to spread. By adding cane sugar in a pulverised state to the lymph I have been able to preserve very considerably the normal characteristics of the corpuscles, and the advanced ones are ren- dered much less liable to spread and enlarge, consequently a greater uniformity of size between these and the primary ones is preserved. Photograph 111, Plate XV., is also a specimen h'om the thyroid gland of the calf preserved in this manner. The preparation was spread out in a thin layer upon the glass slide by forcible blowing with the indiarubber syringe, a cover glass was then laid over it and f per cent, solution of salt run between. Corpuscles of all shades of colour from very dark primary to colomiess ones may be observed. It seems scarcely credible that the corpuscles seen in 110 and 111 should be derived from the same source. In the foregoing remarks I have endeavoured to show that great differences exist among the lymph corpuscles when taken quite fresh from the blood glands of recently killed animals — differences which have their origin not so much in variation of size, as in that of colour and in power to resist the influence of new or altered surroundings. Indeed it would appear that these bodies become, in proportion to the degree of their development, excessively amenable to change when the lymjh is shed or removed from its normal habitat. Now it might naturally be anticipated that with these physical changes of constitution Dr. Nokris on Maimiialuoi Blood. 109 which render the corpuscles more cleHcate, fragile, fugitive, and less visible, there would be concm-rent chemical modifications on which these would be based, and this is really the case, for we find that the relations which these bodies bear to stains is entirely in keeping with tlieir physical deportment. La Photograph 112, Plate XV., is a specimen of lymph from a lymphatic gland which has been diluted with blister fluid, and subsequently stained with saline aniline blue. The aniline blue causes the more advanced corpuscles to become greatly ■enlarged and flocculent or granular in appearance, and simul- taneously they become stained of a deep blue tint. This action of simultaneous staining and enlargement takes place rapidly, and is proportionate to the amount of aniline present. A minute amount of aniline, however, which will scarcely produce visible staining is capable of causing great enlargement. It is curious that when so enlarged they are not globules as might a j)viori be expected, but greatly extended discs, and simul- taneously with this action in the advanced corpuscles, the most primary ones, which refuse the stain, undergo shrinking and contraction. By this means a broad and well marked distinction is established between the two classes of coi"puscles, the primary ones not only refusmg to stain, but also undergoing shrinkmg and becoming distorted and u'regular, while the advanced ones become at once stained and swell up into smooth, regular discs of large diameter, which frequently lie in part over each other as coins might do, thus proving their disc like character. The degree of swelling or extension may be seen by comparing Photographs 101 and 112. The proportion of these corpuscles in various glands appears to differ sometimes in favour of the primary, and at others of the advanced ones. In Photograph 113, Plate XVI., is seen a specimen of fresh sheep's lymph h-om a lymphatic gland. This specimen was first diluted with a f per cent, solution of salt, and then run under a cover glass. On examination the coi-puscles were found to present tlieii- usual appearance. Being subsequently stained with saline 110 Dr. Norris on Mammalian Blood. aniline blue, many previously barely visible corpuscles rapidly put in an appearance, and these became greatly swollen and deeply stained. Between tlie most decided primary ones which are dark, irregular, contracted, and unstained, and are of the smallest diameter, and the advanced ones which possess the greatest diameter, every intermediate diameter and appearance in relation to swelling and staining may be observed. Adhering to the surface of the advanced corpuscles are numerous granules which are obviously similar to those which are free in the liquor lymphse of such specimens, and the som-ce of which will be referred to later on. In specimens of lymph in which these granules are not present the corpuscles are smooth and clean, and this is an additional reason wliy they are to be regarded as merely accidental adliesions. If this view is correct it implies that the advanced lymph corpuscles become, under these abnormal conditions, adhesive and pick up the granules as they float among them. It often happens in specimens of lymph that the advanced corpuscles are only obvious by means of these adhering granules; in other words, the corpuscles themselves are too delicate to be seen. As a further illustration of the effects of saline aniline staining upon the advanced lymph corpuscles Photographs 114 and 115, Plate XVI, may be compared. The former shows advanced lymph corpuscles (and also gi-anules, which appear to have resulted from the disintegration of others,) which have been separated from the primary ones by the method of isolation in virtue of their power to adhere to the glass. Their size and form have been more or less preserved. by means of the ice-cold temperature. In Photograph 115, Plate XVI., the same corpuscles and granules are again shown, after being subjected to the action of the aniline stain. It will be observed that both the cor- puscles and the granules have become greatly swollen, and simultaneously with this have become stained of a deep blue tint. This shows absolutely that the corpuscles and granules which • stain are also those which swell and enlarge, and places in our Dk. Norris on M<(iiiniali(iii Blood. Ill hands a means of distingnisliing from each other not only the corpuscles but also the granules, which result fi-om then- disin- tegration. This differentiating action of the saline aniline blue is very well seen in Photograph 116, Plate XVI., in which the most advanced corpuscles are those which have undergone the greatest degree of extension and swelling, and between these and the dark primary ones, which have become contracted, corpuscles of varying diameters, may be seen which represent intermediate stages of development. Ill Photograph 117, Plate XVI., corpuscles from the lymphatic gland of a pig have been submitted to the action of the saline aniline blue, and we are able to distmguish three states of the corpuscles. 1. The most primary, which have neither spread themselves down upon the slide nor have become stained. 2. An intermediate kind, Avhicli have to some extent spread themselves down, but have not absorbed the dye. 3. The more advanced ones, which in the Photograph show a granular appearance, and which have all taken the stain, but in various degrees ; those whose physical properties are the furthest removed from the primary ones having taken the stain most greedily. The iUustrations and descriptions given will suffice to indicate the natm-e of the general conclusion arrived at by an extended study of these bodies — viz., that they are structures which are undenjoimj a gradual and continuous process of develop- ment which is associated icith chamjes in both their physical and chemical characters. The xDrincipal difficulty that we have in the study of the lymph corpuscle arises h-om its being almost impossible after the lymph is shed to preserve in their full integrity its most developed forms. These can scarcely be brought into contact with ordinary surfaces such as those of glass without being resolved into some one or other of the fibrin forms ; indeed, as before said, they are the source of fibrin in lymph as the colourless disc is in blood. It is owing to this that their existence as corpuscular structures 112 Dr. Norris 07i Mammalian Blood. lias been overlooked, for the fibrin when seen has been accounted for in a very different way. When, however, we become aware that the fibrin present in any specimen of lymph really represents the changed and modified forms and states of its most advanced corpuscles, we at once see that if we would ascertain the relation which these bodies bear to the colourless discs of the blood, we must, if possible, devise means by which they can be . preserved for examination in as nearly as possible their normal state. Considerations of this kind enable us to understand fully the difficulty which has attached in the past to the compre- hension of the mode of development of the blood, for whether we examined the blood on the one hand, or the lymph on the other, the connecting links were in both cases largely obliterated, owing to the corpuscles which bridge over the chasm being in both cases resolved into fibrin, and therefore no longer recognisable as definite structures, but appearing as a third substance of unknown and problematic origin. Under the generic term " lymph corpuscles " a number of bodies have been grouped together and regarded as identical some of which present very marked and characteristic differ- ences, and it has become a common error to regard the white blood corpuscle as tlic type of all these bodies. This practice has given rise to the utmost confusion of thought, and has rendered it impossible to form even an approximately correct view of the nature of the development of the blood. The following bodies have thus been confounded : — (a.) Corpuscles from the lymphatic glands ; {b) Splenic corpuscles ; (c) Thymus corpuscles ; (d) Thyroid corpuscles ; (e) Corpuscles of the supra-renal corpuscles ; (/) White blood corpuscles ; (^/) Leukhaemic corpuscles; (//) Pus corpuscles. Further confusion has also arisen from failing to recognize the fact that these bodies exist in all stages of development. Of the various kinds of corpuscles enumerated a, b, c, d, and e, are alike, and are readily divisible into the two kinds, representing extremes, which we have designated the primary Dk, Noreis an Mammalian Blood. 113 and advanced. It is the destiny of all these bodies ta become red blood discs after having passed through the stage of the colourless disc ; f, g, and h, on the other hand repre- sent certain deviations or departures from this nominal mode of development, represent, in fact, the accidents (so to speak) of the great blood making process. These relations will, however, be better understood as we proceed. From what has already been said it will be seen that the lymph corpuscles in the spontaneous changes which they undergo when the lymj)h is shed, divide themselves broadly into two kinds, and the existence of these two varieties or stages of development is further corroborated by the use of certain staining fluids. If we proceed to inquire more critically into the constitution of these corpuscles, we find that their difference of physical and chemical behaviour appears to rest upon histological diversity ; that, in fact, we have in the primary lymph corpuscle, which has hitherto generally been considered as a nucleus to deal with, a true cell, the outer wall and protoplasm of which is in such close contact with that of its nucleus as to cause them to appear to be, and even to act under some circumstances, as if they were one only. The existence of the external cell-wall can, how- ever, be made very obvious in several ways. In the first place corpuscles possessing it, photograph of a much darker tint, almost, and in some instances, quite as dark as red corpuscles. What the colouring matter is which causes this photogenic reaction we do not know, all we can say at present is that it does not yield the spectrum of haemoglobin. It is, how- ever, nearly as non-actinic as this substance. Examples of these photogenically dark primary lymph corpuscles may be seen in Photographs 103, 110, and 111, Plate XV. The colouring matter on which this non-actinic property depends is not very perceptible to the eye, and is entirely removed when lymph corpuscles are allowed to remam for some time in contact with Liquor Sanguinis. They then photograph as free from colour as the white blood corpuscles. I have not 114 Dk. Norris on Mammalian lilood. found this coloured condition of the primary lymph corpuscle to be present in the spleen, probably owing to the free blood supply of this organ. A further feature which distinguishes the primary lymph corpuscle is the fact that it may, without alteration, remain a long time, (\//., thirty hours in a staining fluid, which at once causes the advanced lymph corpuscles to become deeply coloured, and to swell up into discs of large diameter. Not only do the primary corpuscles not stain or swell, but they actually contract under these conditions, ride Photographs 113, 116, and 118, Plate XVI. If, however, while lying in the staining fluid we mechanically compress these ■corpuscles, the external membrane may be seen to ruptm-e, and the contained nucleus at once stains and SAvells up precisely like the advanced coi-puscle. The only difference now apparent between the two being that some granules which have lefused the stain may still remain attached to the former ; these represent the granular debris of the protective and unstainable capsule. Oenerally these granules remain attached to the edges of the corpuscles, but occasionally they adhere all over them, as shown in Photograph 118, Plate XVI. The Primary Lymph Corpuscle appears, therefore, to consist of three distinct parts. 1. — An exterior layer, wall, or pellicle, which will not stain with the aniline blue nor allow the staining fluid to pass through it so as to affect the interior (nucleus). 2. — An interior mass, (nucleus,) which when exposed by rupture or removal of the capsule, stains easily and deeply, and swells up greatly under the influence of the saline aniline. 3. — A clear colourless liquid, which exudes from this stained mass either fi'om its interior or by a process of separation and aggregation. This refi'actile exudation can take on similar forms to those exhibited by myelin. The Advanced Lymph Corpuscle, on the other hand, appears to consist of two parts only, viz., that which stains and which appeals to be situated externally, and that wdjicli exudes as clear Lyahne liquid, and behaves like myehn, in other words, in the advanced corpuscles the external Mall or pellicle has disappeared. Dr. Norris on jMammalian lilood. 115 Now, if the Primary Lymph Corpuscles are to be regarded .as true cells, or bodies in possession of a cell wall, of a nucleus, and of intra-nuclear contents, then we must con- sider that the cell wall is ordinarily in close contact with the nucleus, and that the development which the corpuscles undergo, when all proceeds normally, consists in the gradual destruction .and removal of this outer capsule, and in this case the advanced .gland or lymph corpuscle will have to be regarded as a freed and developed nucleus, in a word, the primary lyinph corpuscle is a cell containing a nucleus, and the advanced lymph corpuscle is this nucleus set free at a certain stage of its development. The following definitions of these bodies appear to be possible -—Primary lymph or gland corpuscle. A thickish non-nucleated •corrugated disc of an average diameter of 4 to 5*20,000th of an inch, which generally possesses some colouring matter causing it to photograph of a rather dark tint,* but which bleaches if brought into contact with Liquor Sanguinis. This corpuscle refuses to become stained or to swell up into a smooth disc under the influence of saline aniline blue, but on the contrary contracts, and becomes irregular and more corrugated ; when submerged in the liquor lymphse it appears corrugated and rigid ; but when it passes from this influence into a bubble space, in 'Other words, into air loaded with moisture, it immediately becomes lustrous and smooth, exhibits a greenish tint, which photographs dark, and spreads down upon the slide with great increase of diameter, ride Photograph 119, Plate XVI. "When kept under sealed cover glasses in its own liquid (liquor lymphte) it becomes whiter, thinner, smoother, and tends to biconcavity. It rarely, if ever, exhibits amaeboid motion — never, under any circumstances, displays a multi- nuclear appearance, but is susceptible of the peculiar change shown in Photographs 122, 123, and 124, Plate XVI., the * Examples of these dark primary lymph corpuscles may be seen ou Photographs 103, 108, 110, 111, &c., Plate XV, and 116, 120, and 121, Plate XVI. 116 Dr. Norris on Mammalian Blood. natiu-e of which is discussed on page 117. When introduced into blood these corpuscles become the same colour as the Liquor Sanguinis. Advanced hjmiJh or (/land corpuscle. A very delicate, smooth, non-nucleated, fugitive disc, of the same diameter as the red disc. Excessively plastic, falling readily into fibrin forms, stains with extreme ease with the saline aniline blue, and swells up enormously — -say to a diameter of 8 or 9-20000th of an inch, bvit still retaining its discoid form. Much more liquid and mutable than the primary disc, probably possesses amoeboid motion, but this cannot well be made out, for it is too indistinct in the liquor lymphse to be satisfactorily watched — easily spreads down, and is lost as a film upon the shde, vide Photographs 105 and 107, Plate XV. When introduced into blood, or pure Liquor Sanguinis, it is no longer seen. It is this body (which represents the developed product of the blood glands) which passes on into the blood to become in the first place its colourless disc, and ultimately, after acquiring colour, its red corpuscle.''' Anyone who has the most superficial acquaintance with the products of the blood glands will be struck with the protean forms and appearances under which these bodies present themselves, due in part to their extreme plasticity, and in part to their great dependence upon the state, for the time being, of the liquids in which they are submerged,, which, as in the case of the blood, determines not only their size, but also their state as to smoothness or corrugation. The absence also of elasticity in the lymph corpuscle renders it far more amenable to permanent modification of form than the advanced blood corpuscle, but the same is true of the earlier forms of the latter body, which approximate in origin and nature to the lymph corpuscle. It has been before explained that when saline aniline blue * Vide Section "On the identification of the advanced lymph disc with the colourless disc of the blood." Dr. Norris on Mammalian Blood. Ill is used as a means of distinguishing the various developmental stages of the gland corpuscles, it is found that the least advanced or more primary corpuscle is the one which refuses to stain, and which contracts under the influence of the staining fluid, while the most advanced is the one which not only stains readily, but swelling up becomes distended into discs of large diameter. If for the saline aniline blue we substitute a simple aqueous solu- tion of aniline blue, we are able to bring out a still more marked difference in these corpuscles which is of the utmost importance, inasmuch as it furnishes us with an additional demonstration ol the cellular character of the primary lymph corpuscle, and shows the relation which this primary cell bears on the one hand to the uni-nuclear variety of the white blood corpuscle, and on the other to its own nucleus, which in the ordinary and normal coiu'se of events is to be set free and to become the colourless disc of the blood. Unlike the saline, the aqueous staining fluid favom-s endosmotic action, and as a consequence the delicate wall of the cell, which heretofore has been in very close proximity to the micleus, becomes separated h-om it and undergoes distension, sometimes to a very marked degree, so that the corpuscle now exhibits a clear hyaline border, in fact, presents itself as a veritable cell, nucleiTS, contents, and wall. Tide Photographs 122, 123, 124, Plate XVI. Photograph 122 shows the primary lymph corpuscle of the spleen of the pig ; 123 of the lymphatic glands of the pig ; and 124 of the thyroid gland of the calf. Xone of the corpuscles which take on this cellular appearance become stained with the aniline blue. The main variations which they exhibit relate to the extent of the area of the clear zone which suiTounds the nucleus, and to the state of the latter body itself which is sometimes smooth, at others corrugated, and in some cases, where the distension of the cell-wall is very great, it appears even to be undergoing dism- tegration. Under ordinary conditions the nucleus fills up the cell and entirely determines the appearance it will present as to colom*, smoothness, corrugation, &c. ; being, in fact, the body which we see through the delicate cell-envelope, and ordinarily regard as 118 De. Norkis on M