AN AQ WN \ ARK oe. \\ \\ \ CORNELL UNIVERSITY. THE Roswell P. Flower Tibvary THE GIFT OF ROSWELL P. FLOWER FOR THE USE OF THE N. Y. STATE VETERINARY COLLEGE 1897 Cornell University Library QL 737.C2W67 1886 Anatomical technolo iii 3 1924 001 023 294 vet IN U.S, A. PRINTED ® ‘ ANATOMICAL TECHNOLOGY AS APPLIED TO THE DOMESTIC CAT AN INTRODUCTION TO HUMAN, VETERINARY, AND COMPARATIVE ANATOMY WITH ILLUSTRATIONS BY BURT G. WILDER, BS, M.D. PROFESSOR OF PHYSIOLOGY, COMPARATIVE ANATOMY AND ZOGLOGY IN CORNELL UNIVERSITY, MEMBER OF THE AMERICAN NEUROLOGICAL ASSOCIATION, FELLOW OF THE AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE, ETC, AND SIMON H, GAGE, B.S. ASSOCIATE PROFESSOR OF PHYSIOLOGY AND LECTURER ON MICROSCOPICAL TECHNOLOGY IN CORNELL UNIVERSITY, FELLOW OF THE AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE, ETC. | mbRARY FOURTH, FROM THE SECOND REVISED EDITION A. S. BARNES & COMPANY NEW YORK + Copyright, 1882, 1886. A. S. Barnes & Co. ALL RIGHTS RESERVED. QL oad, Cc Ww bo7 (686 PREFACE TO THE FIRST EDITION. TuHIs work has grown out of our needs as instructors of students pre- paring for practical work in Human, Veterinary, or Comparative Anatomy. Most of it has been employed in the anatomical laboratory of Cornell Uni- versity for from one to four years, and we have been led to believe that it may prove useful elsewhere. Some of our laboratory students aim to be professional naturalists, agri- culturists, or veterinarians, but most of them intend to study Medicine or to teach Physiology with other branches in schools and colleges. The latter desire to gain a personal acquaintance with the organs whose functions they are to discuss, and the former require, in addition, a familiarity with anatomical methods and literature; few of them have had any practical training in Biology. The guides to vertebrate dissection by Straus-Durckheim, Morrell, Rol- leston, Krause, Huxley and Martin, Foster and Langley, Bernard, Martin and Moale, and Mojsisovics, present many admirable features, but four of them are in French or German, and none have fully answered our require- ments. Of the works above named, several imply that either the frog or the human body has been previously dissected ; hence, presumably, the brevity of the directions, the lack of descriptions of instruments and methods, and the fewness or absence of illustrations. They are based upon the frog, turtle, dog, rat or rabbit, or on animals in general, and the ordinary anthro- potomical terms of description, upper, lower, etc., are almost uniformly employed. Some dwell only upon points of physiological importance, and in nearly all the references to other publications are few and general. iv PREFACE. So far as we are aware, this work differs from the manuals above men- tioned in one or more of the following particulars :— It assumes no previous anatomical knowledge or experience, yet is rapidly progressive, introducing in succession bones, muscles, viscera, vessels, nerves, brain and organs of sense. It is based upon the domestic cat (see § 124). The terms of description and designation apply to all vertebrates (§ 38); they are technical (§ 29), and precision and brevity have been especially regarded in their selection. The purely descriptive portions are subordinated to the practical and directive. There is a General List of the instruments and materials required for ordinary anatomical work (§ 130), and directions are given for their care. All directions for dissection and manipulation begin with special lists of the instruments and materials required (§ 235). Explicit instructions are given for coarse injections, for the preparation of bones, and for the use of alcohol as a preservative. Certain regions and organs are quite fully discussed, while others are briefly mentioned or omitted altogether (§ 128). Unusual space is given to the viscera (§ 129). The study of the brain includes a consideration of the typical vertebrate brain, descriptions and dissections of the brains of the frog and the Menobranchus, and an approximately complete Descriptive List of the encephalic parts, with References and Synonyms. There are illustrations, and the methods of making the preparations figured are fully described. The abbreviations are of the technical names only, and they are nearly uniform throughout. As far as possible, the technical names are written in full upon the figures. In the explanations of the figures, the technical names and the abbreviations are alphabetically arranged (§33). There are numerous Alphabetical Lists, Tables of Synonyms and Tabular Arrangements of names according to the relations of parts (p. xxvi). Attention is called to the incompleteness of our information upon cer- tain points. There are frequent cross references and numerous definite references to other publications (§ 2); the titles of the works and papers cited (three hun- PREFACE. ‘v dred and thirty in number) are given in an Alphabetical List of Authors at the end. While, therefore, the book is designed primarily as a guide for beginners, certain features—the references and the suggestions as to lines of inquiry— may prove useful to teachers and others who may undertake to add to existing knowledge. _ Histological facts and methods do not come within the scope of the work, but at the close of the discussion of most of the organs is given a summary of (A) the obvious or macroscopic structure—that which may be determined with the unaided eye, and (B) the fine or microscopic structure. The latter is in no sense complete. It embraces only the points upon which most standard authors are agreed and which may be demonstrated without a great expenditure of time. Only the structure of the given tissue is con- sidered ; hence the presence of vessels and nerves is not mentioned. It it be desired to carry the histological inquiry farther, the works of Quain, Stricker, Ranvier, Beale, Frey, and the special papers therein referred to, are recommended. Among the many friends who have aided or encouraged us, our thanks are especially due to Professor Oliver Wendell Holmes for helpful criticism of the terminology and for suggesting the preparation of a manual in which it should be incorporated ; to our colleague, Professor J. H. Comstock, and to Professors E. OC. Spitzka and T. B. Stowell for valuable suggestions and for the adoption in their writings of the descriptive terms herein employed ; also to the last named for a critical revision of the early manuscript of the muscles, and for the important additions to knowledge contained in his recent paper on the vagus nerve of the cat. To all of our laboratory stu- dents we are indebted for aid, suggestions and criticisms, and especially to those (see end of Bibliography) who have selected parts of the cat as subjects of their graduation theses, Our acknowledgments are here made to the American Philosophical Society for the use of the four lithographic plates, and to the firms named in the List of Illustrations for the courteous loan of electrotypes of instru- ments manufactured by them. The original figures were drawn by the persons named in the Note pre- ceding the List of Illustrations. The three ladies have also been our stu- vi PREFACE. dents, and have shown more than ordinary interest in their work. Most of the original drawings were made by our colleague, Professor E, C. Cleaves, whose skill, patience, and accuracy only artists and anatomists can fully appreciate. There has been constant codperation throughout, but, it may be proper to state, the senior author holds himself particularly responsible for the Introduction, the Preservation of Soft Parts, the Bones of the Limbs, the Muscles, the Heart, the Central Nervous System and the Cranial Nerves ; and the junior author for the Preparation of Bones, Coarse Injections, the Skeleton excepting the limbs, the Viscera, the Peripheral Vascular and Ner- vous Systems and the Organs of Sense. Notwithstanding our efforts for accuracy, there are doubtless errors of observation and interpretation. Corrections or suggestions will be gladly received. PREFACE TO THE SECOND EDITION. From their own experience and from the testimony of teachers and students elsewhere, the authors believe that this work answers the purpose for which it was written, viz.: to furnish those who intend to pursue human, veterinary, or comparative anatomy with explicit directions for dissection and for the preparation and preservation of anatomical specimens, and with a correct and clear account of the principal parts of an accessible and fairly representative mammal of convenient size. Although arranged for the convenience of beginners, the figures and descriptions are based upon repeated dissections by the authors, and thus constitute an original monograph upon the anatomy of the cat, serviceable for comparison in researches upon other forms. The errors and oversights detected in the first edition have been corrected in this, and, in accordance with the progress of anatomical knowledge and a change of the authors’ views upon certain points, some new matter has been added and some of the old restated. The more important changes are as follows : 1. Four figures have been replaced by others representing, respectively, the entire neuron in horizontal section (Fig. 110, p. 408); the mesal aspect of a brain separated into its five encephalomeres (Fig. 117, p. 444a); the mesal aspect of a brain lacking the callosum (Fig. 118, p. 449); a transection through the medicommissure (Fig. 122, p. 458). 2. Three Tables have been revised, viz.: Names and Synonyms of the encephalic segments (p. 405); Names of the Principal Parts of the Amphib- ian Brain (p. 409); List of Names and Abbreviations (pp. 436-438). 3. Sixteen pages of new matter have been introduced, viz.: (a) The use of slips in scientific correspondence (p. 52). (0) The use of peroxide of hydrogen in bleaching bones (p. 111). (¢) The methods of starch injection (leaflet between pp. 140-141). (d) A revision of the method of injecting the lacteal trunks and thoracic duct (p.364). (e) A description of the new figure 110 (p. 410). (f) A detailed description of the new figure 117 of the mesal aspect of the brain (pp. 446-448). (g) A commentary upon Chapter X (pp. 400a—-400d) in respect to the structure and names of certain parts, the general constitution of the brain and its preparation by the injection of iv PREFACE. Miiller’s fluid, or of alcohol into the vessels or cavities. (h) References to the writers who have adopted the new terms of designation and description (p. 534). (i) A supplementary index. (/) A list of additional references to publications. The following is a nearly complete list of the minor changes and typo- graphical corrections made in the present edition : P. 75, lines 9-11 read: Messrs. Schuyler & Co., and White & Burdick, of Ithaca, for $6.25. It contains the following instruments : Three assorted scalpels, coarse and fine forceps, coarse and fine curved scissors, arthrotome, tracer and blow-pipe. P. 159, § 410, 4th line. For caudal portion, read cephalic part. P. 164, § 429, 11th line. Read: diapophysis of the corresponding thoracic vertebra. P. 184, 12th and 18th lines. Read: It passes along the carotid canal and unites with a larger vessel extending along the mesal side of the bulla. P. 202. For 6 read: Have plenty of light upon the part under dissection so that details of structure may be seen. P, 238, § 649. Under General Description, for dorsimeson, read ventrimeson. P. 264, § 686. Under Origin, 10th and 11th lines, for radial artery and nerve, read brachial artery and median nerve. P. 264, § 687. Under Origin, 7th line, for radial artery and nerve, read A. brachialis and N. medius. P. 277, § 718, 8d line. For thorax, read abdomen. P. 365, § 991, last line. For dorsad of the aorta, read dorsad or ventrad of the carotid. P. 386, § 1026, 4th line. For ist cervical, read 7th cervical. In each of the three following places, for root, read trunk : p. 888, last line; p. 389, first line; p. 395, § 1048, 5th line. P. 512, § 1899, line 22, add: on the side of the face, in the ventral lip. P, 489, § 1324, 5th line. For caudal, read ventral. P. 522, § 1424, 9th line, and p. 525, 8th line. For macula lutea, read discus opticus. In respect to nomenclature the authors are assured that the innovations embodied in the first edition were in the line of real and natural progress. The descriptive terms apply equally to all vertebrates and the terms of designa- tion are, for the most part, brief, capable of inflection, and equally intelligible to anatomists of all nations. They realize, however, that the use of words with obviously Latin terminations, even when the terms are more or less familiar, imparts to a sentence a decidedly un-English look, and that, for most readers, the technical Latin names would be more acceptable if in an English dress, or with a vernacular face and aspect. In accordance, therefore, with considerations more fully presented in the senior author’s paper (G4), the desirable English appearance of the newly added pages has been attained, not by reverting to English translations or heteronyms of the Latin names, but by converting the latter into their PREFACE. . Vv natural English paronyms.* For example, myelon becomes myel (adjective myelic) ; mesocelia, mesocele; pedunculus, peduncle, etc. To have paronymized all the names would have involved resetting the entire work. Examples may be found upon the new figures 110 and 117, upon pages 400a—400d, and in the following list : List of names, mostly encephalic, illustrating the methods of reducing Latin polyonyms to mononyms, of converting Latin mononyms into English paronyms, and of forming adjectives therefrom : LATIN. \ ENGLISH. Polyonyms. Mononyms. Paronyms. Adjectives. Pars media ventriculi communis.) Aula........... Aula vod eves es Aulic. Hippocampus minor.....0.. 005 Calear.........s Calcar.i.csees Calcarine. Corpus callosum .. 1... eee. eens Callosum....... Callosum ..... Callosal. Nucleus caudatus.............. Caudatum...... Caudatum.....} Caudatal. Tractus transversus pedunculi...| Cimbia.......... Cimbia........ Cimbial. Substantia cinered........-.4.. Cinered.......4. Cinerea........} Cinereal. Provessus clavatus oo... cece eee Clava oo ec eeee Clava......... Clava). Musculus coracoideo-brachialis...| Coracoideus.....| Coracoid... ..| Coracoid. Plexus choroideus ventriculi tertit] Diaplexus....... Diaplex....... Diaplexal. Diencephaion....| Diencephal....) Diencephalic. Musculus pectoralis externus s. MOJO caro ces ae v semen aoa ain Ectopectoralis ...| Ectopectoral..| Ectopectoral. Pia mater interior. ......eeee es Hindyma........ Endyma....... Endy mal. Fascia dentata...........00. eee Fasciola........ Fasciola...... Fasciolar. Corpus fimbriatum.........005. Fimbria........ Fimbria....... Fimbrial. Commissura fornicis.......006. Fornicommis-| Fornicom- SUTA oo. eee eee missure..... Fornicommissural. Porniz cerebri...... cece sieve eie| OPRUBE «a ieawl ean Fornix........ Fornical. Hippocampus major..........4. ee es Hippocamp Hippocampal. Ansula Retlti.. ccc cece eee Insula . Insula........ Insular. dter a tertio ad quartum ventric- WWM saslisnceanie sce 69 00s MaRS Wet ess oon ercases | AECP es ex aca wed Iteral. Foramen infundibuli........... LUI an wi nena Lutag co cccaccan Lural. Arteria cerebralis media........ Medicerebralis...| Medicerebral..| Medicerebral. Commissura medid...........6- Medicommissura.| Medicommis- sure......... Medicommissural. Ventriculus mesencephali....... Mesocelia ...... Mesoceele...... Mesoccelian. Ventriculus quartus ........... Metepicetia......| Metepicele .../ Metepiccelian. Tela choroidea inferior......... Metatela........ Metatele . Metatelar. Chorda spinali8......0eeecee eee Myelon......... Myel.. Myelic. Medulla oblongata..........0666. Oblongata....... Ghlongaia, Oblongatal. Pua Mabe cs vicina on sees es yx sox Pies nisaa sevens Plas osveca ets Pial. Pons Varolit.... 0.00. cece ceee PONS 25 skit ace Pons). 465.05 220% Pontile. Foramen Monroi..........000- POTO ooeericnscons POA ics aiserisis Portal. Vena cava posterior. ........05. Posteava..... Postcava......| Postcaval. Cornu posterius ventriculi later- CIB ining waves GRY AS Ses OS Postcornu...... Postcornu...../ Postcornual. * The terms paronym and heteronym were suggested by our colleague, Prof. Isaac Flagg. Paronym (compare the Greek wapwviuia) indicates a name which is cognate with or radically allied to another; heteronym is its natural correlative and implies the absence of such relationship. For example, canal is the paronym of canalis, whiie its heteronyms are groove, furrow, aqueduct, etc. vi PREFACE, LATIN. ENGLISH. Polyonyms. Mononyms. Paronyms. Adjectives. Nares posteriores ... 0.20... e eee Postnares......+ Postnares..... Postnarial. Fissura centralis antertor....... Precentralis....| Precentral. ...| Precentral. Pedunculus cerebelli superior...| Prepedunculus..} Prepeduncle...| Prepeduncular. Ventriculus lateralis..........- Procelia .......,| Procele....... Procelian. Ventriculus quintus..........65 Pseudocelia..... Pseudoceele....| Pseudoccelian. Gyrus frontalis inferior s. tertius| Subfrontalis.....| Subfrontal.....) Subfrontal. Pars superior ossis occipitalis ...| Superoccipitale..| Superoccipital.| Superoccipital. Lamina terminalis...........4. a Terma........ Termatic. Thalamus opticus...........64. Thalamus ...... Thalamus..... Thalamic. Valvula Vieussenii............. Valvula........ Valvule....... Valvular. Cornu anterius 8. ventrale myel- ONIE iocdue nee tae ee ainissles wee Ventricornu....| Ventricornu...| Ventricornual. The method, paronymization, applies to other languages ; e. g., from the Greek mipauic, we have the Latin pyramis, the English pyramid, the French and German pyramide, and the Italian piramide ; so the Greek éyxépadocg becomes L. encephalum or encephalon, E. encephal, G. encefal, F. encéphale, and I. encefalo. In view of the above examples there seems good ground for hoping that the recognition of the principle of paronymy may facilitate the establishment of a universal scientific language, combining with the perfection of Latin construction a far greater richness and precision. As a whole, then, the vocabulary which seems to us best calculated to facilitate the advancement and dissemination of accurate anatomical knowledge may be contrasted with that which is in common use as consist- ing of terms which are : Designatory rather than descriptive. Vertebrate rather than human. Restricted rather than unrestricted. Correlate rather than irrelate. Co-ordinate rather than inco-ordinate. Classical rather than vernacular. Dissyllabic or trisyllabic rather than monosyllabic or polysyllabic. Mononymic rather than polyonymic. Paronymic rather than heteronymic. The authors desire to express their sense of obligation to Dr. Spitzka for Fig. 118; to Messrs. D. Appleton & Co., for the use of Figs. 110, 117, 122; to many friends, especially students, past and present, for helpful criticism ; to the reviewers for their courtesy toward what was in some respects a departure from established customs; and finally to the publishers for the liberality with which they have seconded the efforts to render the work a substantial contribution to science. CONTENTS. INTRODUCTION. PAGE References to Publications: .. cc .csnes vase wesseaieas Gases ous a ewedeues dad xe 1-3 Method of reference to authors. .......... ccc eee eee eeeenees é 2 Catalogue of scientific papers published by the Royal Society of London .. 3 Deécimal..SystemSiois.5 sccccines seacnecs sua oe otnewre eokn eR ewlpaleterat vale mene sees 3-8 Centigrade Thermometer—Fahrenhett’s Thermometer... . 0.0.0 cece cece cee eeaes 3 Comparison and reduction of the two thermometric scales................ 3 Table of equivalent temperatures according to the Fahrenheit and Centi- grade thermometers 2.0.4 ¢ sects asuuwesded chases 4 eee EEA Emde de 4 Formule for the reduction of the Fahrenheit and Centigrade scales and vice VETSO 5 ss ass Habelediog’a Cataeeed ory rahseGoa tiie SPs SAE Neavaialuceures ew 4 ST We MEL UG SY SLE NI: «rec vicesi oui eee uta Pe San sla we beo deus ate Sm Slee aces eae Resear ehh a0 4-8 Meter, liter and gram—definitions and common equivalents.............. 4 Comparison of the metric and English systems of weights and measures... 5 Table of the metric measures.................000. eee se ecore aye dalanacies fain cts 5 How to learn the metric system.......... 00. c cece cence ace eeeenaes 6 Table of equivalents of metric and English measures... .......es.c0ee0ee 7 The metric system in medicine... ...... 0... cc cece cee ene e eens 8 Zoological Classification. ...... 6... cee ccc cece ene ce eee e eee eee enens 8 Table illustrating classification ......... Lice eee cece cece ee ee een ees 9 Wer Mino logy couse c tiwlidceds sae e wae pa DUReud deo Nehad vee SUadommecawan Genes 10 Character of the terminology here used...........0. cesses sence ee eeees 10 General considerations upon anatomical terminology...........s00.eeeeee 11 Aphorisms upon terminology from various sources ...........--0eee sees 12 Brief statement of the objects and methods of the terminological changes ELE MAASY vies isis sin aac Miiduatsatsiacuaeging alien nea. narainauide wiawaee te 13 Designation of Orguns—OrganonyMy .. 0. ccc cece cccccccvccancen ceeeeceenee 14 General considerations by various authors... 0... ...... cece eee eee ee eee eee 14 Importance:of brevity .<.isccceicesscevaeecavversessedsas tauren sia ses 15 + Comparison of technical and vernacular terms in science ..............+- 15-17 Ease in acquiring technical terms................. Linea Dnata 17 Names indicative of relative position........ 2. ccc. cc ce cence eet e eee eees 7 The limits of terminological change. ........... 02. cece cece eee ee ence ees 18 Priority and etymological appropriateness of technical terms............. 18 Some inconsistencies in the nomenclature here adopted...........0.0-005 19 Names and abbreviations on the figures .......... 6... cece cece cee eee 20 Vili CONTENTS. PAGE Terms of Position and Direction—Toponymy...... 0. ree reeeerersreneecenees 20 The normal position of the body.... -6. sess eeeee tence eeee eee reer ence 21 Designation of the aspects of animals......-+.-ee.eeeeeeee rece eeees eis 21 Views of Barclay and others .....----ssseeereeee sp Bay SRR OMRE 635 4 FRc 21-22 Ambiguity of terms..........--+5++ ee eee ee ee 22 Intrinsic Toponymy ........ 0. ccc cece eect eee ce beet e nee tenet tere eee e ens 23 Cephalic and caudal, dorsal, ventral, dextral, sinistral, lateral and mesal— signification and use by various authors ...........2. esse eee eee ee 23-24 Ventrimeson, dorsimeson, intermediate and medial............-..---00 : 25 Designation of the Regions of the Limbs.......+5 ses cereceeeeenen ee ceeeneees 25 Proximal and distal extremities. ......... 0.6 ee cee cece ee eee eee eee er eee 25 Cephalic and caudal, dorsal and ventral aspects............ esse eeee eee 25-26. Other names for the extremities and aspects..........-0..ee eee ee teens 26 Terms of General Application to the Whole Body... ...cecccccceceeeeer tc nenes 26 Central and peripheral, ectal and ental.......... 0... eee e cece eee ere nee 26-27 Inflections: €tes o: awerces seas sed coe sd padeaciowi geet Pos ee ieee te SETA alee 27 Adjective ndingsy 14354655444 neverce sees sees a we aamdlpmuey ee deere wes 27 Use of the prepositions of and from... 1... ce cece cece eect ence eee eees 27 Limitations of accuracy ....... 60. eee eee ee eee eee Rowaudd we ees eaS 27 Derivatives, connecting vowels Of......... ccc cece cece ee een eee ere en eens 28 Compound words—Hybrid words. .........0.. cece ee ee eee sundae Seite sieae 28 Primary Divisions of the Body—Soma and Membra.................0.-..0008 29 Axial portion, soma—Appendicular portion, membra—Truncus or trunk.. 29 Comparison of right and left (dextral and sinistral) in the object and the ODSELVED ainaneaee aus veces shea Mes S84 sOREwEasE a adres 228 eee Ga eR 29-31 Position and direction on the soma... .. 0... . cee eee eee eee eee eee eee 31 Columna vertebralis, its constitution and location ................0eee eee 32 Canalis neuralis and ccelum or general body cavity............... ...... 33 Essential characteristic of all vertebrates. ........... 0... ccc ee eee eee eee 33 BODY: PUONCB) ecscct Sessa seiacaie ayer baa teemleh EN COTS Sew ae Tad ARREARS SOR ORR HES 33-34 MesOc cinco gia Soseumnaavslltl es Gigammaninds Lune vheddtanaees See _tntestinum te “LNT Pp sistday aporgry? fue (oaprougors 6 aloznsre Dic) e074 UE] MIA TSURIITKS middle arthra-._ Pi “ \ Se ‘ A Poy “ 18, ‘ 12 4 Pay eg. gyedsvn 2, Cae fg le SS eg et wy fale : (ejopiwnstd) ganuzn rie wen bow .¢3p107ad Day a 9) 0.4 2Uz9’ mn z3d Ds} fuumpop) auouny) wenapa sequy’ /'+ saproydors) eyorpos’ Fic, 6.—DraGram of THE Dorsal ASPECT OF THE CAT, WITH TIE LIMBS IN THE NorMAL POSITION. 38 39 DIVISIONS OF THE BODY. ‘yoof) seq ‘Wadoud B92) sna [ (85a) pury—nojays) SQAT ) ‘(yhiy2) sora J \ -(uonguod innapuaddp—squiy)) e IQUId IAT ) ‘(puny) snuey ‘(usuotof) umiyserqayuy } (sha quoLf—NULD) SINUY ‘(un vaddn) wmniyserg | ‘(a2) epned ‘™) VaNnvo } *SIATag | ‘(igaq) vawopqy be " “(un) SNONNUL “(Gsayd) xeIOULL ‘(yoau) umyo * + + + “(y00u) INA T1109 ‘unIUeID }. “5 (pny) LNdIVO J "398 . * (uonsod ev) eui0s | ‘(4p9) SNAUOD ‘4poq) SNdYOD AHL AO SNOISIAIG IVdIONINa AHL 40 ATEVL 40 INTRODUCTION. is not easy, with most Mammals, to replace them in the normal position. It may, however, be readily accomplished with an orang, and without much difficulty with the arms of a cat or a child. The student may exemplify the normal position of the arms approxi- mately by getting upon all-fours, placing the palms upon the floor at either side, with the fingers pointed laterad ; the convexities of the elbows should then be made to look dorsad and laterad, upward and outward. If now the arms be extended laterad to their utmost length, still keeping the palms against the floor, and the elbows away from it, the limbs will have nearly the position shown in figures 6 and 7. § 81. Limb Segments.—With the cat, as with most air-breathing Vertebrates, each limb presents at least three divisions or seymenta, con- nected with each other and with the soma by three arthra (joints or articulations). These segments and arthra are thus proximal, intermediate, and distal. As shown upon the right of the diagram, the proximal segments are brachium (upper arm) and meros (thigh). The intermediate segments are antebrachium (forearm) and crus (leg proper). The distal segments are the manus (hand) and pes (foot). The entire limbs are joined with the trunk by the shoulder and hip joints, while the eldow and knee intervene between the brachium and ante- brachium, the meros and crus, and the wrist and ankle between the ante- brachium and manus, the crus and pes respectively. The technical names for the arthra placed in parenthesis are those which were pro- posed in 1878 by the senior author (10, 18); but as they have not been generally adopted they are not insisted upon here. Each manus and pes also presents a threefold division, carpus, metacarpus, and digits (thumb and fingers); tarsus, metatarsus, and dactyls (toes). The distinctive names for the digits and dactyls are placed under them. The primus (great toe) is represented by a dotted line, in consideration of its absence from the cat. § 82. Limb Bones.—On the left side of the diagram are shown the bones corresponding to the segments already enumerated. The proximal segments have each a single bone, the humerus and femur, which are represented as subcylindrical, with enlarged extremities. The intermediate segments have each two bones, ulna and radius, tibia and fibula, which, in the normal position of the limbs, lie side by side, the radius and tibia on the cephalic aspect of the limbs, and the ulna and fibula on the caudal. These bones are likewise subcylindrical, but the ulna and tibia are larger at their proximal ends, while the radius and fibula increase more or less distad. The patella (knee-pan) and the olecranon and other special features are not shown. CARPUS AND TARSUS. Al § 83. Marsh has proposed (Z) to apply general names to the corresponding bones of the arm and leg. Thus, the bones of the proximal segments are the Ossa propodialia ; the radius and ulna, the tibia and fibula, constitute the epipodialia ; the bones of the carpus and tarsus are mesopodialia ; the metacarpalia and metatarsalia are—as indeed they have previously been called—the metapodialia, and the old term phalanges is retained for the bones of the digits and dactyls. § 84. Carpus and Tarsus.—The carpailia (bones of the carpus), and the ¢arsalia (bones of the tarsus), are variously interpreted by different writers; see Balfour, A, II, 508. The following general description, based chiefly upon the researches of Gegenbaur, is given by Huxley, A, 31 :— «There is reason to believe that, when least modified, the carpus and the tarsus are composed of skeletal elements which are alike in number and arrangement. “One of these, primitively situated in the centre of the carpus or tarsus, is termed the centrale ; on the distal side of this are five carpalia, or tarsalia, which articulate with the several metacarpal or metatarsal bones; while, on its proximal side are three bones—one radiale or tibiale, articulating with the radius or tibia ; one wlnare or fibulare, with the ulna or fibula; and one intermedium, situated between the foregoing. “Carpal and tarsal bones or cartilages, thus disposed, are to be met with in some Amphibia and Chelonia, but, commonly, the typical arrangement is disturbed by the suppression of some of these elements, or their coalescence with one another. «Thus, in the carpus of man, the radiale, intermedium, and ulnare are represented by the scaphoides, lunare, and cuneiforme respectively. The pisiforme is a sesamoid bone, developed in the tendon of the J, flexor carpi ulnaris, which has nothing to do with the primitive carpus. The centrale is not represented in a distinct shape, having probably coalesced with one of the other elements of the carpus. The fourth and fifth carpalia bave coalesced, and form the single wnciforme. See § 421. ‘In the tarsus of man the astragalus represents the coalesced tibiale and intermedium ; the calcaneuwm the fibulare. The naviculare (serphoides of Anthropotomy) is the centrale. Like thé corresponding bones in the carpus, the fourth and fifth tarsalia have coalesced to form the cuboides.” § 85. In the cat, so far as we can judge from the figures and statements of Flower (36, 138), and Mivart (B, 96, Fig. 60), and from our own observations, the condition of things is as follows :— In the ¢arsus, aside from peculiarities of shape, the tarsalia and their connections are as in man. In the carpus, the same is the case, excepting that the scapho-lunare represents not only the scaphoides and the lunare—the radiale and inter- medium of the primitive carpus—but also the centrale. Flower found 42 INTRODUCTION. this element distinct in a dog; the senior author has observed (19, 301, Fig. 1,) it as a separate center of ossification in a young lion, shown in Figure 47; and it is apparently shown, though not alluded to, by Mivart, (B, Fig. 60.) There are many interesting and important questions connected with the composition of the carpus and tarsus of different Vertebrates, and those interested in the subject may consult Gegenbaur (Lankester), A, 479-481, 487, 488, and the papers of that anato- mist, Morse (18 and £) Marsh (Z), and Wilder (26). § 86. The metapodials are comparatively simple elements. In the diagram, the pollical (first) metacarpal is made shorter than the rest, as is the case in the cat, and the primal (first) metatarsal is represented as a slight rudiment, the remainder of it and the whole dactyl being absent, and hence shown by dotted lines. The ordinary digits and dactyls have each three phalangeal segments, proximal, intermediate, and distal. The pollex has but two, and in those Mammals which have a primus, this usually consists of but two phalanges. § 87. This peculiarity of the pollex and primus has always constituted a main argu- ment in favor of the prevailing view as to the correspondence of the limbs with each other—intermembral homology. According to this view, the cephalic borders of the arm and leg correspond, morphi- cally as well as telically ; the radius is the homologue of the tibia, and the ulna of the fibula ; and the pollex is both the homologue and the analogue of the primus. This, the syntropical idea of intermembral homologies, has been adopted, in one form or another, by nearly all anatomists. The other idea, that of untitropy, has been advocated or accepted by a much smaller number, including the elder Agassiz, Coues, Dana, Foltz, Wyman, and the senior author. According to this view, the two ends of the soma, and thus the cephalic and caudal aspects of the limbs, are reversed or symmetrical repetitions of one another, as are the cor- responding organs upon the right and left sides. The radius thus becomes the homologue of the fibula, and the tibia of the ulna, while the pollex represents the quintus, and the minimus the primus. Fully recognizing the apparent objections to this view, we nevertheless believe it to be correct, and would refer those interested in the subject to the paper (10) by the senior author, where these objections are discussed and the opinions of other writers stated, with a List of Works and Papers treating of the general question. § 88. Enumeration of Parts in a Series.—As has been stated (§ 30, 79), two or more similar parts which form a series are enumerated in order, beginning with the one nearest the head, or the meson, or the proximal end of the more comprehensive part of which they are subdivisions. On the diagram (Fig. 6) are given some illustrations of this method. The vertebre have been referred to already. Of the digits and dactyls, the most cephalic in each series may be designated as the first; but it is evident that this might cause confusion in the case of animals having only four or a less number of fingers or toes. a TRANSECTION OF A MAMMAL. 45 s It is often desirable to describe the place of origin or insertion of muscles as from or upon a given fraction of the entire length of a long bone. When the area extends over athird of the whole length the thirds would be designated usually as proximal, middle or distal; but when fourths or smaller subdivisions are employed, they may be designated as first, second, etc, as shown upon the femur in Tig. 6. Dorsal aspect B \ s neuralis 2 ee a PL esa st x Pe 5 - aorta one D --Oesophagus 2 [--trachea “[-pulmo (lung) dexter elbow Aw GE, m, ea Sri nalé \ carpalia “sternum ng ( \metabarpale wh cot” carpus. ‘phalanges Ventral aspect - Fie. 7.—DIAGRAM OF AN IDEAL TRANSECTION OF THE THORAX OF THE CAT, WITH THE ARMS IN AN APPROXIMATELY NORMAL POSITION, AND SHOWING THE LOCATION OF THE PRINCIPAL VISCERA. § 89. In Fig. 7, the cut surface is viewed from the caudal aspect, so that the right and left parts are as in the other diagram (Fig. 6). : As a whole, the body is symmetrical, the two halves being reversed repe- titions of one another on opposite sides of the meson. No definite separation exists between the dorsal and the ventral regions. We may, however, speak of the dorsal and the ventral aspects, and the vertebral column, or main axis of the soma, intervenes between the dorsal cavity, or Canalis neuralis, and the ventral cavity, the cwluwm, whose more cephalic division or thoraz is here transected. The Canalis neuralis contains the myclon, and the ceelum the organs of organic life, the thoracic, abdominal and pelric viscera. The following parts and organs are mesal or approximately so, at least in the embryo: nose, tongue, myelon, centra vertebrarum, aorta, esophagus, trachea, heart, sternum. The following are in pairs: eyes, ears, kidneys, coste, costicartilagines (costal cartilages), pulmones (lungs), pleure, limbs. The right lung is shown as a single and simple sack, communicating 44 INTRODUCTION. @ with the trachea. The left lung is reduced to give place for the names of the cavity. Each pleura is seen to be a closed sack, which lines the corresponding side of the thorax to form the ectal or parietal lamina, and is reflected upon the viscera to form the ental or visceral lamina. Between the heart and the sternum, on the meson, the two pleure are in contact, and form the septum mediastinale. For the sake of simplicity, the pericardium is omitted, and the heart shown as a single cavity with regular walls. The single vessel emerging from the heart will be referred to in § 91. The spaces on either side, between the skin and the osseous walls of the celum and Canalis neuralis are occupied by the muscles, etc. The arms have their elbows directed dorsad, and the palms ventrad. The caudal aspect is seen, the bones including the ulna and the ulnare (un- ciforme), and the minimal metacarpal and phalanges. § 90. Relative Positions.—The letters A-L are introduced into the diagram for the sake of illustrating certain common cases of designation of relative position. The point A is at the meson on the dorsal aspect of the body ; its posi- tion may be described as dorsimesal. B, C, and D are lateral in position, or, to be more specific, sinistral. Relatively, B is daterad of A, while C is dorsad of D. Since they are upon a curved surface, B may be described as either dorsad or mesad of C; while C may be said to lie either ventrad or laterad of B. Which expres- sion should be employed would depend upon the context; in either case, practically, there is no room for ambiguity. ictal and Ental.—Of the three planes represented by C, E, F, the former is relatively ectal, the last is ental, and the third intermediate. Proximal and Distal.—G is at the proximal end of the humerus, and FH at the distal end. G is thus proximad of H, and H distad of G. Central and Peripheral. —On the artery, I is centrad of K, and K is peripheral in comparison with I, but centrad of L. On the nerve which leaves the myelon, M and N are relatively central and peripheral. § 91. Use of some Terms of Relative Position in a Physiological Sense.—Central and peripheral, and sometimes other terms are employed in a physiological rather than in a strictly topographical sense. For example, on the nerve the ventral curve is really, that is topographi- cally, nearer the myelon and the meson than N ; but N would nevertheless commonly be described as centrad of the curve. A striking case of this sort is furnished by the recurrent laryngeal branch of the NW. vagus. In a part of its course, it curves around one of the great arteries near the heart, and then passes cephalad to the daryna, Now the larynx is much nearer the brain, where THE SLIP-SYSTEM. 45 the WV. vagus arises, than is the heart; topographically, therefore, the termination of the nerve is nearer the brain than part of its trunk ; yet the termination would be described as the peripheral portion. On the artery shown in Fig. 7, ventrad of the bones of the left arm, K is peripherad of I, and Lof K. If the arm should be so flexed as to bring the artery into the position of the dotted lines, L’ would be topographically nearer the heart than K, but would nevertheless be a peripheral point on the vessel. A somewhat similar case is offered by the abdominal portion of the ali- mentary canal as shown on Fig. 6. In the strict topographical sense, the cecum and contiguous portion of the smadl intestine lie caudad of the colon. In some cases, a description would refer to this fact, but it would be never- theless understood that, physiologically and in respect to the course of the contents of the canal, the cecum is intermediate between the small intes- tine and the colon, and is therefore caudad of the one and cephalad of the other. The relation in the one case is merely of contiguity ; in the other, of structural and functional continuity. V.—THE SLIP-SYSTEM OF NOTES. § 92. The following suggestions as to “notes” are here introduced not because, like the foregoing matters, they render what follows more intelligible or available, but because, taking for granted that none will have got so far in the volume without the intention to do some serious scientific or literary work, we desire to put them in possession of a method which has proved most useful to us, and which we shall be glad to have adopted by our readers even if their only employment of it is in recording criticisms of our statements and ideas. § 93. The essential feature of a ‘‘slip-system” is the use of separate slips of uniform and convenient size. Accessory features concern the precise size and form of the slips, the way of writing wpon them, and the manner of their filing and distribution for reference. § 94. After constant use of the slips for fifteen and seven years respec- tively, we make the following specific recommendations :— § 95. The Slips.—Excluding those used in the Catalogues of Libraries and Museums (which will be referred to farther on) the note-ships should be of unruled paper ; white, blue, light brown or yellow in color ; slightly sized, so as to take either the pencil or the pen ; moderately stiff, but not thick ; and of the size of the U. S. Postal Card, at present 13 x 7.7 cm. § 96. Making Notes.—Some of these slips should be carried in the pocket at all ‘imes, preferably in the pocket-book, which is usually large enough for folded letters. 46 INTRODUCTION. Temporary memoranda may be made across the slip, but all other notes should be written lengthwise, and preferably on one side only. § 9%. Slip notes are of the following kinds: museum catalogues; library catalogues ; references ; extracts; clippings; statements of observations or ideas, original or otherwise, with or without drawings. § 98. Library Catalogues.—The titles of hooks and papers should comprise at least the following data: the author’s name and surname or initials ; the title and subtitle of the book or paper. With a dook, the edi- tion, size; number of pages and illustrations ; the place and date of publica- tion. With a paper, the Periodical in which it was first published, dates of presentation and publication, the volume, part, pages and illustrations. With both, references to Translations and Abstracts. The foregoing data are entered in various orders, and with different kinds of abbreviation. Those who desire to adopt some standard method of writ- ing titles should consult the ‘‘ Catalogue of Scientific Papers” published by the Royal Society of London, the publications of “The American Library Association,” and the “List of Periodicals taken by the Public Libraries near Boston.” A. One of the valuable suggestions of the Library Association is that the more com- mon given names should always be indicated by the initial, this initial being distinguished from the same letters used elsewhere by a colon following: For example, E. might stand for Edwin, Egbert, Edmund, ete., but E: would always signify Edward. B. Another suggestion, that the sizes of books should be indicated not by numbers but by the initials of the words signified by the numbers, as O. for octavo, etc., is carried out in the “ List” just mentioned, and is made more available by the use of the ‘“ Book Size Rule,” provided by the Readers and Writers Economy Company, being a metric rule, 30 cm. (1 ft.) long ; this is also a convenient desk rule. § 99. Catalogue Data.—On the face of the Museum Catalogue Card should be noted the following : Museum number, original number, class (of animals), series (of specimens or preparations), genus, species, common name, locality, sex, age, dates of collection, death, and reception (which do not always coincide). This should leave the lower half of the face for a brief description of the preparation ; purpose for which it was made ; reference to any original list, to publications, etc. On the reverse of the slip should be, after a repetition of the museum number: the original weight of the brain, and of the body, and the ratio in decimals; the present (usually alcoholic) weight of the brain and body; the capacity (of an inflated preparation); the length from vertex to anus (of an entire example); by whom collected; when and by whom prepared ; donor or seller; his address; original cost, expressage, etc., hours’ work; estimated present value; museum numbers of other specimens from the same indi- vidual ; numbers of other preparations from members of the same litter; numbers of other specimens with which this may be instructively compared. HOW TO TAKE NOTES. AY With care in the arrangement and abbreviation of these points, all may be entered, together with others not here specified. We have not yet fully determined upon the best form for the Catalogue slip, and hope others will offer the results of their experience. For library and museum catalogues, the slips should be of heavier and stiffer paper than for ordinary notes, and the surface should be well-sized, since ink is commonly employed. § 100. References.—The slips may be used for brief references to works, papers, persons, addresses, localities, museums, etc., constituting, in fact, permanent memoranda, which may be filed with more elaborate or extended materials upon the same subjects. $101. Extracts.—Upon one side of the slip may be written from 40 to 50 words, either by hand, or with the type-writer when the lines are at medium distance, 1 cm. apart. At short distance, the number is just doubled, and, if necessary, both sides may be written on, or two or more slips may be used, or a sheet may be used, and then folded to the slip size. § 102. Clippings.—Clippings from periodicals and newspapers may often be accommodated upon the slip. When no longer than the slip is wide, they may be pasted at either end, with the lines always lengthwise of the slip. When the length is greater than the width of the slip, the columns, if narrow, may be pasted side by side; but usually so much as exceeds the width must be pasted on the remaining space so that the lines run across the slip. By thus covering both sides, a single slip may receive an entire column of “The Medical Record,” or ‘‘Science;” more than half a column of “The Nation,” and nearly half a column of the ‘* New York Daily Tribune.” Even when unaccompanied by the signature of some well-established authority, such clippings serve as memoranda which may aid in looking up the matter farther, and as more or less valuable confirmatory evidence. § 103. Notes Proper.—The most common and most important use of the slips is as a ready and convenient vehicle for the many kinds of informa- tion which the scientific or literary worker desires to record and to use. The Slip is Always at Hand.—It may be written upon without parade, and under almost any circumstances, whether sitting at the table, or riding in the cars, or even on horseback; whether engaged in regular work, or conversing with friends, or even at night and in the darkness. Under all these conditions, more or less favorable, the essence or “pith” of a fact or idea may be recorded, though sometimes in a shape quite unintel- ligible to others and well-nigh so to the writer, unless an early opportunity is taken for putting it in better form. § 104. Accumulation and Elimination of Slips.—The beginner’s object is to accumulate the brief records of what he has learned, but is not sure of remembering when wanted. After the first year, however, many of the things thus recorded become familiar as the alphabet, and much also that is supposed true to-day may be 48 INTRODUCTION. disproved to-morrow, or superseded by more accurate descriptions, more perfect drawings, and more logical discussions. With the ordinary note-book, or Index Rerum, all these untruths, half-truths, or truisms must forever remain where they were placed. From being merely superfluous, they soon become burdensome, then confusing, and finally a source of loss and exasperation. Not so the slip; the instant its usefulness is at an end, into the waste- basket it goes, making room for more desirable successors. § 105. Arrangement and Storage of Notes.—After trying many different plans, we make the following practical suggestions :— § 106. Slip-Portfolios.*—The slip-portfolio is for bolding the notes upon a given subject. It is made from a piece of stiff Manilla paper, 16 x 13 cm., and folded over a pencil so that the folded edge is left rounded. The slips are introduced, the title of the subject is written along the top, and the whole is bound together by arubber band 7 cm. long by 1 mm. thick, like No. 372 of the Price-list of the R. and W. Ee. Co. Such a portfolio will hold 50 slips, but usually when there are more than 25 they should be subdivided. § 107. Subdivision of Notes.—Let us suppose that the student is collecting information respecting the heart of the cat. While his notes are few, all may be contained in a single portfolio. As they multiply, they naturally fall into four categories relating respectively to the structure of the organ, its functions, its development, and the titles of works and papers treating of it. As the notes increase under each of these heads, anatomical notes may be divided naturally into sets relating respectively to the appear- ances which are visible to the eye, those which require the aid of the micro- scope, and those which involve special kinds of manipulation, as boiling, etc., in order to display the arrangement of the fibers. The macroscopic anatomy may refer to the awricles, the ventricles or the valves, and each of these headings may be still further subdivided. We see, therefore, that without the subdivision of the notes upon five quite extensive topics, the heart might require the use of a dozen separate portfolios. Since all of these concern the heart, they may all be bound together by a stronger band, say No. 385, 8 cm. long and 3 mm. wide ; or, they might be bound in two sets, the one including all the divisions of the gross anatomy, and the other the rest. , Such a plan of subdivision is not only convenient for reference, but furnishes an exercise in Natural Classification ; see p. 49, § 108. § 109. Distribution.—Since it is not always convenient to assign the * The employment of the portfolios was suggested to us by Wm. Nichols, M.D., of Boston, Mass. 49 SUBDIVISION OF NOTES. ‘(g) Areuowpng (9) pidsnorg. “LD)NILLJUID-OMNAULN YT *(y) ptdsnoiy, ‘ ‘SHATVA i "1 8 bpungnuagy | (6) OoW “OD spray wot y / ‘SH TOINOY (LT) omen yr aybray (BL) ajanequa 4 oT ) | + ‘SHIOIMING A J X81) aponuguag gyorg J 2) AHdVUNOI11_ (8) LNAWNdO1S Aaa (8) ADOTIOISAHd r°LVD HO LUVAH ‘() ADOTOLSIH (g) SnoudIa f° + + * ‘AWOL LWNY J “ * *"§soup 2 ‘SZLON JO NOISIAIGGNY ALL ONTILVULSATH Tisvy, ‘goT 8 59 INTRODUCTION. notes to their proper places at the time they are made, it is well to have an extra portfolio, which, in this case, would be marked, ‘‘ Heart of Cat ; Distribution.” When its contents are to be distributed, the other portfolios are arranged upon the table in some natural order; the removal of their bands will permit the upspringing of the side so as to expose the heading, and facilitate the introduction of slips. § 110. Slip-box.—This should be of stout tin, preferably Japanned. The inside measures of length and width should be 22 cm. x 14 cm. (about 9x 5.5 in.), which is nearly the size of the ordinary sheet of note paper. The depth is less simply stated. If the box has a folding lid, like the “Japanned tray, postal size,” here figured (Fig. 8), a depth of 8 cm. will be needed. But the scientific student has such abundant need for shallow trays, that he will usually find it more convenient to have, in place of the folding lid, a single cover, 2 cm. deep. This should overlap the edge of the box for 1 cm., resting on a welt. The depth of the box itself will then be only 7 cm. If the slips are kept in envelopes instead of portfolios, the box and cover together should have a depth of 9cm. The Japanned tray, “standard size,” is only 5 cm. deep, and if the “postal size ” is ordered, care should be taken that it is of the actual width required for the postal card, since some the of so-called ‘‘ postal slips” are only 12.5 cm. long. The free edges of the box and cover shoulc be turned, and the latter should be “soldered.” $111. Cost of Materials.—The tin box may be had for from 50 cents to $1.00. A tn cash-box, with lock, costs $1.50. The Japanned tray, postal size, with slips, blocks and guides, costs $2.65. “Roll Manilla,” 40 inches wide, is 8 cts. per yard; including the cutting, the slip- folios cost at the rate of 10 cts. for 25-35. The bands are rated at $2.20 per M. for No. 872, and $5.85 for No. 885. By the hun- dred they cost proportionally a little more. The slips may be cut by hand, but it is usually cheaper to have the cutting done by the stationer. They cost from 50 cts. to $1.00 per M. § 112. Other Methods.—The slips may be placed in envelopes, sealed at the side, and with the right end cut off. If this plan is adopted, it is true economy to use stout envelopes which will not readily fray and tear. Cloth-lined envelopes of the proper width, 9 cm. (three and one-half inches), may be had for about $2.50 per hundred, and are practically indestructible. Another way is to write the heading upon a card the size of the slips, and put (iti, SSCL Fic. 8.—THE JArPANNED TRAY, FOR CATA- LOGUE SLips. READERS AND WRITERS Economy COMPANY. PREPARATION OF MANUSCRIPT. 51 the band over all. Finally, there is the method exemplified by the accompanying figure (Fig. 8), which seems, however, better adapted for museum and library catalogues. § 113. Using the Slips.—For ordinary reference, the portfolio is held in the left hand, the band removed, and the slips turned until the desired one is found. As a basis for manuscript or lecture-notes, they may be arranged in the proper order by spreading them out upon the table; more or less condensa- tion and elimination will then occur. The selected or condensed notes may be used as lecture-notes, or their substance transcribed to sheets. § 114. For carefully prepared manuscript, the following stages of com- position are recommended :— 1. Slips, hand-written. 2. Slips, selected, condensed, and, if possible, type-written. 3. Sheets, hand or type-written, into which the type-written slips may sometimes be incorporated by pasting. 4. Sheets, carefully type- written, a corrected copy of the first set. Manuscript so prepared, especially if in addition an interval of at least one week elapses between the first and the second copies, will usually need few changes in proof. § 115. Sheet-Portfolios.—The sheets referred to are of the standard note size, about 21x 12.5 cm. Such sheets and drawings of similar size may be conveniently kept in sheet-portfolios of the Manilla paper, double the size of the sheet, say about 21 x 27 cm. Portfolios of sheets, or the sheets themselves, may be conveniently kept in the “Pigeon Hole Case,” “ pamphlet size,” supplied at $1.50 by the R. & W. Ke. Co. The case shown in the figure ABLE Pidees Horm Cie, BEET is known as the “Billet size.” For size. READERS & Writers Eco- “note sheets,” there are only two tiers of nomy Co., (A:) holes. Fig. 9.—UNIFORM, INTERCHANGE- $116. Miscellaneous Suggestions.—A. By writing the portfolio headings with pencil, they may be changed as desired, and to any extent. Even if written with ink or printed, however, each portfolio presents four surfaces which may be used in turn. $117. B. The type-writer or calligraph can be adjusted to any width of paper. Of course, the longer the line the fewer the shiftings ; but the narrower sheet is more easily manipulated, especially when changes or divisions are required, and it is often a real ad- vantage to be able, without delay, to write alternately upon tie shcets and the slips. §118. C. While assorting alarge number of slips for which portfolios have not been prepared, it is sometimes desirable to remove them all without mixing the separated piles. This may be accomplished, either by interposing a blank slip between the successive piles, or by placing them crosswise, and carrying a band over them diagonally. 52 INTRODUCTION. 8119. Origin of the Slip-system.—It is probable that the slip-system has been devised independently by many individuals, and we are informed that Mr. Folsom, the Librarian of the Boston Athenzeum, proposed the use of slips in Card Catalogues at the Librarian’s Convention in New York in 1852. Asa means of recording and arranging scientific information, how- ever, the first published notice known to us is the following by the senior author (17), communicated tothe Boston Society of Natural History, May 15, 1867 :— § 120. “It consists in the brief statement of facts, ideas, or references to books, written upon one side of a slip of paper equal to the sixth part of a sheet of note paper. “A few of these blanks are carried in the pocket, and advantage is thus taken of op- portunities for recording and preserving information which the time, place, or state of mind would not permit to be written out in full, or which might be forgotten before a fitting opportunity should occur. “ These slips are distributed at leisure into envelopes bearing the title of the subject. “By keeping the slips separate, it is evident that an indefinite subdivision of each general subject can be made by simply increasing the number of envelopes and redistri- buting the slips. “The slips may be used either for simple reference, or, if in preparation of a lecture or communication, by arranging them on the table in any desired order, and transcribing parts of them in the form of notes; while for a written paper they serve to indicate the general order of discussing a subject. “The method proposed makes sure of the essential fact or idea in a brief form, and the slips, being kept separate and of uniform size, may easily be arranged, carried and arranged, or rearranged in any order at any time.” This plan was presented in a lecture at the session of the Anderson School of Natural History on Penikese Island, in July 1873, and, according to a report in the N. Y. Tribune, ‘was almost universally and immediately adopted.” § 121. The Use of Slips in Scientific Correspondence.—The following is from a note by the senior author in “Science,” v., p. 44, Jan. 16, 1885 : During last summer I began to use slips in another way, suggested, perhaps, by the fact that postal-cards referring to a single point were frequently filed with the slip-notes on the same subject. As compared with a letter in the usual form, such correspondence-slips present the following advantages: 1. Each point may be attended to by the sender or the receiver independevtly of others which may require more delay; 2. Without transcription, the slips may be filed with others on the same subject; 38. The same slip, with or without attachments, may be sent back and forth, or to other correspondents, for comment or in- quiry; 4. The date of each writing may be affixed by hand or by the use of Perkins’ rub- ber stamps or other mechanical device; 5. If written closely or with the type-writer there is usually ample space, not only for the original note, but for an answer to it, if it was an inquiry; a second slip is attached if necessary; 6. It is convenient to APHORISMS OF GENERAL APPLICATION, 53 keep envelopes already addressed to those with whom one desires to communicate fre- quently, to insert the slips when written, and to send the letters as occasions arise. From a note in “Science,” v., p. 86, Jan. 30, 1885, by Mr. B. Pickman Mann, it appears that he had used slips for many years, and that they had been employed for correspond- ence between Dr. George Dimmock, bimself and others. § 122. Rules and Aphorisms of General Application. “Tn the order of Nature, doing comes before thinking; Art before Science.”—Joseph Henry (Mayer, 1, 95). “Personal familiarity alone makes knowledge alive.”—Philip Gilbert Hamerton. “Practice the utmost rigidity and thoroughness in research, without regard to time consumed, or value of results.”—Henry James Clark (Pack- ard, 1). “‘Lenteur dans la marche; aridité dans l'étude ; solidité dans les prin- cipes; stireté dans les résultats; ce sont 14 les attributs des sciences d’ob- servation.” —Bichat, A, i, p. v. Correct methods are the keys of knowledge. Whoever has learned how to work has taken a long step toward indepen- dence of teachers and books. “The method may determine the result.”— Louis Agassiz. “Tf rescarches take at the first step a wrong direction they diverge the farther from the truth the farther they are followed.”—Gadoriau. “It is often as if the truth were rather whispered than spoken by Nature.”— Owen. Accuracy is more to be desired than speed. Books may be consulted in haste, but Nature demands deliberation. Non-discrimination is no proof of identity. Ignorance of a specimen’s locality may cause delay; an error respecting it may create confusion. As is the locality to an individual, so is the individual to any of its parts. “There is so close a solidarity between ourselves and the animal world that our inaccessible inward parts may be supplemented by theirs. * * * A sheep’s heart or lungs or eye must not be confounded with those of man ; but so far as the comprehension of the elementary facts of the physiology of circulation and of respiration and of vision goes, the one furnishes the needed anatomical data as well as the other.”—AHualey, 3. “Carpenters and tailors do not learn their trades upon rosewood and cloth of gold.”— Wilder, 2, 8. ‘‘Felitomy should be the stepping-stone to anthropotomy.”—Jdem, 2, 6. “‘No medical student should be wlowed to dissect the human cadaver until he has familiarized himself with the anatomy of the cat.”—Cleven- ger, 1, 1. 54 INTRODUCTION. He who can skillfully dissect a cat will find little difficulty in dissecting a man. ‘« Fiat experimentum in corpore vili.” The softer the parts, the harder their study. Soft parts are perishable. Hurried dissection is rarely trustworthy. The thorough examination of soft parts can be made only under one or more of the following conditions: A. Limitation of the inquiry; B. Abun- dance of material ; C. Continuity of dissection ; D. Co-operation of several dissectors ; E. Preservation of the parts. Filth and bad odors cannot always be avoided, but their continuance is rarely necessary. Accurate knowledge of a few things is better than vague ideas concern- ing many. First expressions are rarely correct or perfect. A description is perfect only when it enables one who has never seen the object to form a correct image of it. ANATOMICAL TECHNOLOGY. INTRODUCTORY. § 123. This work treats mainly of the Gross Anatomy of certain portions of the Domestic Cat, and of the Methods of their Examina- tion and Preservation. Reasons for Selection and Preference.—There shall be given here a condensed statement of the reasons for selecting the Cat, for giving almost exclusive attention to the Cephalic region of the body, and for devoting to the Brain and other Viscera a relatively large amount of space. § 124, For Selecting the Cat.—Three things are to be learned by the student of Anatomy and Physiology, whether Human, Veteri- nary or Comparative : methods of manipulation; fundamental facts of structure and function ; and terms of expression. Most of the methods might be learned upon any mammal, but convenience and economy are consulted by the use of one which is at the same time widely distributed, common, easily kept in con- finement, and of moderate size so as to be readily manipulated and cheaply preserved. Methods cannot be practised without some knowledge of the nature, location, and uses of the parts concerned ; and the record or communication of results involves the use of terms; hence there is effected a substantial saving of time, mental effort and expense by employing, in the acquisition of methods, a form anatomically and physiologically comparable with those which the student is pre- paring himself to investigate. The adult human subject is inconveniently large, not always easy to obtain, and often expensive when all things are considered. The immature individuals (still-births) which 56 INTRODUCTORY. may sometimes be had, lack the firmness of texture which is desirable for the examination of certain parts. The veterinarian is especially interested in the horse and the cow ; but these are too large and costly for elementary work ; in less degree, the sheep and the pig are open to the same objection. The needs of the comparative anatomist were well expressed in the course of a “ Labora- tory talk,” by the late Prof. Jeffries Wyman, as recorded by the senior author (2, 5):— “In commenting upon the unsatisfactory nature of some published notes of dissec- tions, he said : ‘Much of this is due to the lack of suitable standards for comparison, The human body is not a suitable standard for the lower vertebrates. The best thing any anatomist can do is to prepare complete accounts of the structure of a few forms, each typical of some large group. The fowl could represent the birds, and the cat the mammals. The cat’s anatomy should be done first, because it would also serve as an introduction to Human Anatomy, and thus become an important aid to Medical Education.’ ” . Theoretically, among known forms, the wants of the comparative anatomist might be more fully met by the more generalized opossum or raccoon. The tiny musk-deer of Java could be more easily dissected and preserved than most of our hoofed quadrupeds ; while a medium sized monkey, especially after some confinement, is the best possible substitute for the human subject. Unfortunately, however, none of these animals is sufficiently abundant in all parts of the civilized world, and we must select such as are to be had. The rat is certainly too small for most purposes, and not easy to obiain unmutilated. The rabbit, like the rat, belongs to a group of peculiar mammals, the Rodents, with no special advantages in respect to either human or veterinary anatomy. Dogs vary greatly in size and mode of life, so that no one of the many breeds can be fairly spoken of as the dog, and although, as stated by the senior author (21, 308), the pectoral muscles present less variation than might be expected, few comparisons have been made of the other soft parts except- ing the brain, where, as regards the disposition of the cerebral fissures, the variation is considerable and perplexing (Wilder, 12, 242). So far as we can judge from published records and our own observations, cats are much less subject to variation than dogs. They are both walkers and climbers, and therefore comparable with the domestic quadrupeds on the one hand, and with the monkeys, and through them with man, on the other. They are common in most civilized lands, fertile, easily reared, and may be kept in confinement, even in considerable numbers, without difficulty. They quickly succumb to anesthetics, and their size is such as to facilitate both dissection and preservation in alcohol. They are quiet, while dogs are noisy. § 125. Of a less practical nature, yet well worth mention, is the remarkable combination in the cat’s organization, of delicacy, agility and strength ; a combination which seems almost perfectly adapted to the prolongation of individual life and the perpetuation of the species. Indeed, as well remarked by Mivart (B, 493,) ‘‘Something may be said in favor of cats being the highest of mammals, if man is considered merely in his animal capacity, in which alone he can be brought into comparison with other organisms.” See also Minot, 7, and Dana, 123, 160. This idea will be acceptable to those who prefer the purely teleological aspect of Nature. Others, however, may find ample ground for discussion respecting the universal operation of the doctrine of Final Causes, at least in the present state of our knowledge. Teleology has not yet explained the existence of the insignificant clavicle, the rudimentary primal metacarpal, the little pocket at the border of the ear, or the cusps on the deciduous man- dibular canine teeth, § 126. In short, while freely conceding the advantages which might be presented by INTRODUCTORY. 57 other forms, especially if it were practicable to supply a separate standard for the anthro- potomist, the zoologist and the veterinarian, we nevertheless believe that even then these three might be advantageously compared with the cat as a fourth and intermediate form, and that, when all points are considered—size, habit, distribution, physical endow- ment and zoological position—the cat should be chosen over all others, both as a single standard for comparison, and as a subject of elementary and preliminary anatomical and physiological work. § 127. Nor is this choice wholly without precedent. It is true that descriptive and practical works upon Mammals have been more often based upon others than the cat. For obvious reasons, the horse has been the subject of many publications ; the rabbit is selected by Krause (A), the rabbit and the dog by Foster and Langley (A), the rat by Rolleston (A) and Morrell (A), while Coues has described (47) the skeleton and muscles of the opossum. Yet Straus-Durckheim devoted a magnificent monograph to the bones, ligaments and muscles of the cat ; and reduced copies of his outline plates, with a translation of the “ Explanations,” have been published by our colleague, Prof. Henry 8, Williams. The skeleton is delineated and named, in connection with those of the Duck and the Codfish, by E, Tulley Newton (A), and as the work was “prepared under the supervision of Prof. Huxley,” the usefulness of the cat has probably been appreciated by that zoologist. Finally, the recent volume by Mivart (B) purports to describe the entire structure of the cat, although no practical directions are given, and, according to notices in The Nation for June 2, 1881, and in Science, and The Atheneum for June 4, the author seems to have made somewhat frequent and wholly unspecified substitutions of human anatomy for that of the cat. The junior author has published two papers (Z, 3) upon the anatomy of the cat ; and the desire for a complete account of its brain, expressed by the senior author in 1873 (11, 229), has been recently, in part, fulfilled in the papers numbered 2, 3, 4, 5, 6, 7, 8,9, 12, 13 and 14. § 128. Reasons for Treating of only Part of the Body.—This work is primarily an explanation of methods, and the descriptions of organs are mainly in illustration thereof. The account of only forty muscles covers an equal number of pages. To devote a pro- portionate space to the 150 or more other muscles, and to all the arteries, veins and nerves would swell the volume to undesirable dimensions. Some selection was therefore neces- sary. Of the two general regions of the body, the cephalic is certainly more familiar to most persons, more interesting, more employed in art, more often used in experiment, and more subject to injury and disease. To obtain and prepare the heart and the brain involves some manipulation of the thorax and head. The arm of the cat is more complete than the leg, since it has all five of the digits, and presents the interesting and important provision for the rotation of one of the epipodial bones about the other. Notwithstanding our doubts respecting the homologies of the Jf clavo-trapezius and some of the antebrachial muscles, the myology of the arm is in a more satisfactory state than that of the leg, where the great ‘‘adductors” are likely to puzzle anatomists for some time to come. In short, the same practical considerations which have led most anatomists to describe the muscles of the antebrachium with more fullness than those of the back, have induced us to select the arm rather than the leg for the more detailed descriptions. 58 . INTRODUCTORY. § 129. Reasons for Giving Unusual Prominence to the Vis- cera.—It is stated by Macalister (British Association Report, 1877, p. 94), that ‘at least 600 bodies are annually examined in the dis- secting rooms of Great Britain and Ireland;” yet how few are the published observations respecting the characters, constant or variable, of any parts other than the bones and the muscles. In this country the case is still worse, and we have no journal espe- cially devoted to Anatomy and Physiology. This comparative neglect of the internal organs is probably due, in great part, to the fact that, as remarked by the senior author, (2, 9), the average “ human subject is rarely available for the study of viscera. Usually some of them are diseased. The heart is apt to be full of injection-mass. The brain and abdominal viscera decay so rapidly that some of their important features are soon obliterated; and when, as is customary, their removal is postponed until after the examination of the overlying muscles, their condition is often such as to render them unfit for preservation. How many students have gained a good view of the thoracic duct, or the sympathetic ganglia? How often has it been ascertained whether a subject has two pancreatic ducts or only one? Is a satisfactory examination of the brain made by the majority of dissectors?” In short, do not the larger number of medical students regard the viscera, even the heart, as simply a mass of ill smelling material, difficult to examine, not very instructive, and worthy only of the waste pail? Whatever be the cause of this inattention to the viscera, the fact leads us to give ample space and illustration to these organs as they exist in an animal peculiarly adapted for their study and preservation. Moreover, although a predilection for surgery prevails among medical students, most of the diseases they will have to treat affect the viscera rather than the skeleton and its muscles; physiology, too, is largely splanchnological, and a correct knowledge of the brain is yearly more desirable in connection with the pro gress of rational Psychology. Lastly, notwithstanding the general preference of systematic zoologists for skeletal characters—a preference certainly based upon convenience, and, in respect to fossil forms, upon absolute necessity—we are disposed to think, as suggested by Gill (J, p. xxvii) and the senior author (22, 189), that the more comprehensive vertebrate divisions should be founded upon cerebral and cardiac characters. CHAPTER I. LIST OF INSTRUMENTS AND MATERIAL FOR ANATOMICAL TECHNOLOGY—DESCRIPTION OF INSTRUMENTS AND APPARATUS—CARE, POLISHING AND SHARPENING OF INSTRU- MENTS—METHODS OF KILLING ANIMALS—PRECAUTIONS FOR CLEANLINESS—DEO- DORIZERS. § 180. Anatomical Instruments and Material—tThe follow- ing is a General List of the Supplies required for anatomical work. A Special List will be given in connection with each kind of manipu- lation. The names are arranged in alphabetical order. Common letters are used for the names of instruments and materials which are desirable, especially in a large laboratory. The names in black letter are of articles which are regarded by us as indispensable to the performance of the best kind of work. Several articles are not marked indispensable because for them may be substituted others which, although less perfect and satisfactory, may be cheaper or more easily obtained. For example, ordinary cotton may be used instead of the absorbent, a pail or box in place of the anesthetic-box, crockery instead of glass, etc. Of the two syringes, the cheaper is marked indispensable, but the more expensive will answer the purpose more conveniently. In the first column are given the numbers of the figures of the instruments and appa- ratus in this work. In the second column, the sections are named when possible. Usually these sections occur within the present chapter, but in some cases, as with Alcohol, Jars, etc., the articles are treated of elsewhere, as may be ascertained from the Index. In the last column are given the maximum prices of the less familiar articles. They are usually taken from dealers’ lists, and are therefore based upon the ordinary weights and measures. It will be understood that prices vary according to the quality of the goods, the state of the market, and the distance of the dealer from the place of manufacture. Illustrated Catalogues of Anatomical and Surgical Instruments, of Tools, of Glass-ware, and of Chemical Apparatus and Supplies, may be obtained of dealers, as, for instance, Codman & Shurtleff, of Boston, Shepard & Dudley, of New York, and Snowden, of Philadelphia ; A. J. Wilkinson, and Goodnow & Wightman, of Boston ; Whitall, Tatum & Co., of New York ; J. & H. Berge, of New York, and others. ARTICLE. Fig. SEc. PER PRICE Absorbent cotton......... ee eee eee en eee eee eee ps 134 Tb. $1.00 Alcohol, ethyl...........-.. siesiueuscaa ne Ones a ch. III gall. 2.50 Alcodmeter (alcoholometer), or hydrometer. ... 4 o oe 2.00 Aneesthetic-box. .... 0.5.0 cece cece en center eee 29 194 ie 1.50 Animal charcoal..........00-eeee eee e eee ae 198 Tb. 10 Arseniate of 80d&... 1.0... ese cee cee ee ee ee eeee oe ch. III Tb. 20 Arthrotome. sais cde dee vascds cece ee SERA Rees 16 135 ae 70 60 ANATOMICAL TECHNOLOGY. ARTICLE. Fie. SEc. PER PRICE Atomizer or spraying apparatus....... soos aie os ee ae 1.25 Bags, coarse, for cats....... i Shoaib anes ee Basins, graniteware....... ccc cece esee eevee a a Béaded, bristles .o:ssc sis s\scis gree sae gare ma . 136 ‘ Benzine ssa2seusass save secnienee tend ewe.s oe ees ‘ as oes Bistoury, concave, blunt point................ ua ot we 1.25 ae small, straight, blunt point.......... 14 i 1.25 i i a sharp point.......... Pe as 1.25 Blocks, LOM THO CM ones Giesaiaee mod ve Sere wioas ce 137 er 24 Blow pipe, flexible............. ec cece eens 19 138 a 25 Bone chisel sciwoacecan see nse eae es th ieee Og si site 1.00 Bottlé brushes)... s.0.seccacecea sea ees crane ee 34 ee doz. 2.00 Butcher knife, small........ 02... .. eee eee eee z sa 50 Cans and boxes, metal.......... 0.0.02 eee eee ‘ we ch. III Canulie, 21as8 occa cca cea ea sae asieaaee oi ieiee ¥ 36 . . Carbolic acid, strong ......... 0.20.02 cece eee a sve ° Cats sesseaste ees renn dase alnadwgela sien es aie 139 om af Chain: hookse:i.o0c cas aecusiechau tots aces Ss a 140 bie 50 Chamois leather’ sc¢ ies. .aa as neensseseewanes 3 ns ai me ChIGPOfOTTO ve) Sea es ves aie a eerie ee 8 a8 Ib. 2.00 ClO VE: O10 ce sions ameneis keen ead ghee aaS sebains a ses ts we Compressor, small............ ec cece cee eee 18 141 pair 8 Corks, assorted ss: < ssccecigs ihe es genase ae #642 - o Cork presser Cosmoline or vaseline........... 0. cece eee ees ss oe 1b. 30 Cotton, COMMON scssaws eae eee eed ae tees DeOdOMIZEIS icc.Samige sesictue en bas Gade ee Ae aie aii se a Dishes, glass, covered ..........-. ec eee eee eee 33 ch. III doz. 3.80 Dissecting-Gown........ 00.0... cece ee ee eee ee oe 142 Drawing materials......................00. oe 143 Drills and stock, sssccw pale la sgiy s con sieisheier artes ie 144 Emery; fnesticas cade inxs sends ve vas peas cess a8 a Enterotome: 5 sass scesevadsawas ved Beacueeien’ #3 159 a3 + Ether, sulphuric.................- Sidis onilanntuet ar Fer ai 2.00 POT a eis ods wiedgsternmciand cule sidan Ma amen 5 ae Mi 5.00 Footilath@riiss piace cee aarGakoutivanweaaiene os ans ee 25.00 ~ FOrCépS, COATS) ssc. sssxas maniac saree seu 18 145 Oe T5 ee AINE CUTVEGicdate a eaaiggie outer see 20 146 aM 85 Glycerin, COMMON... sis ccscnns secaveeseur tes a aif lb. 50 Graduate; Class: 20. esis ixcease Gs ovedeeet< wh of Hone, finest Arkansas oil-stone............... ss 184 os Hone, mediums .c sic vicascacdwirn tet ones anes i 184 Hydrometer jar, 12x 2inches................. oa ch. III ‘ Injecting materials, colors, etc............. a ch. IV a's oe Instrument cases. .........6 066 cee eee ee eee ee i 171 Jars, glass, wide-mouthed.................... sis ch. III Knitting needle, smallest.................0.. : Lamp, Bunsen or spirit ........... 0.0... 0e eee ae oi Metric rule, weights and measures...... esas os 13 . INSTRUMENTS AND MATERIAL, ARTICLE. Muslin; cheap: 2s. ag 22294 oni weet er seca ns Nail Driishis « seviwied ese va aias camiecaes wee bees Needles, post mortem..................0 0000s Nippers, large and medium.................. Nippers, small, Stubs’s................ 0... Nitriciacid..:.sssiceews er eaves aiacyeew acne oie Oil, olive or sewing-machine................ Oiler, glass or metal. ..... 2... eee eee cee Parchment for labels......... 0.0.0... c cee eee Parchment numbers....... 2... c cc ccc cece ees Permanganate of potassa..... 62. 0.....0. ce Pins, assorted, and ribbon.................00. Plaster, adWesive...i 00 sucess a ececeued dees ae Plaster of Paris, finest dental ............. Pliers, round nose, 5-inch........... cc. ee eee Probe, silver, with eyelet....... 2... 00.0000. Rouge; jeweller’. seis 00 este eeaneys bes eee4 Rubber bands, assorted........... .....ceeee Rubber G1Ovess cc cce ee aavs eevee ccesancwoes Rubber sheeting........ 0... cee cece eee ee Rabber tubing once seve eestor neewsads eee Saw, back, small... ... 0... cc. cece eee ce ee ees Scales, large and small.......... 2.0.00. ee eee Scalpels, large, medium and Charriere...... Scissors, coarse, curved flatwise........... Scissors, “ e edgewise........ ; ef medium, curved flatwise............ “fine, curved edgewise.............. Waits ecie oss swier pasa aed's es Seles Sodium chloride (common salt)............. Sponges, small........... 0.02. eee ce eee Stropy FAZOT saosin i ese asain touddlagals Syringe, brass, with canula.................. " tubber DUD: s.sescecesc ccs esau evetadts ff swhite atietal 2 ic0-eice peste ee tes MYT ZOOM ES... 4. ei ssaeeia va oe eal Maat sans Tags: for labels... seis acca ceceess ca peas Tena cul dso is oid oe oa Maewreaniws enpeweconnens Tools, carpenter’s cv tamsens sy vee owns wwe x Towels, fine crash, 45x70 cm.............. Tracers, sharp and dull.................... Trays, tin, copper, or wood...........6. .66- Tripod magnifier..... 2... 0. cece ee ee eee eee Tubing, glass, small... .... 0.0.0.6 ec eee eee ee Tunnels, fluted tube.......... cc ee eee ee eee ee Turpentine, spirits of...............0.20 ee eee Twine and thread, linen...................- Fic. 11 10 38 17 78 26 SEc. 146 146 147 149 148 198 61 PER PRICE 75 1.00 50 14. ast SO wo woe gr w oc ame M. in 60 62 ANATOMICAL TECHNOLOGY. ARTICLE. Fic. SEo. PER Prick Vials, large-mouthed..........ees cece eeeveee ah ch. IIL Waste pail, covered ...... 60+ e cece cere enero ae 196 Waste papers... .. cece ec cee ee en eee e ner eeens i 195 ate Watch glasses. ........ 2 ce cece cece ee eens ee pt. II doz, 2.60 Wetting bottle... 0.6... cece ee eee ete eee 27 170 Wire, brass, copper and iron. ..........+ eee as § 133. It will be seen from the foregoing list that the absolutely necessary instruments for ordinary anatomical work are compara- tively few and inexpensive. : In purchasing instruments, the student should remember that their value depends not upon their handles, their finish, or their cost, but upon the adaptation of their size, form and temper to the work in view. On the other hand, while perfect instruments alone will not insure a good dissection, they are generally more easy to use, and more durable. Hence it is cheaper, in the end, to purchase the best. Left figure, ordinary “cutting nippers.” Right figure, “diagonal side cutting nippers,”’ called xippers in this work. Middle figure, blades of nippers seen from the side. § 134, Absorbent Cotton.—This is cot. ton freed from all impurities, and especially from the oi/ which ordinary cotton retains Yin small amount. It is therefore not J only cleaner, but capable of absorbing water or alcohol instantly. On this account it is to be preferred for the cushions which are made for freshly prepared brains, em- bryos, and other soft and delicate specimens to rest upon while hardening. It should also be used for packing small or delicate alcoholic specimens for transportation ; the ordinary cotton occupies much more room at first than after it is thoroughly soaked, and a space is thus left in which the specimen can be shaken to and fro. When ordinary cotton must be used for either of these purposes, it should be first thoroughly soaked. For dry packing, the ordinary cotton will answer. § 135. Arthrotome—Fig. 16.--This is a strong scalpel, two edged for about 1 em. from the point. The handle is steel, continu- ous with the blade, and roughened like that of the anthropotomical, “cartilage knife.’ The arthrotome should be used for the rougher § 7 x ze ae Zo za a 3 3s Fig. 10.—Stuss’s NIPPERS, x 83; § 146. BEADED BRISTLES. 63 d edgewice.| né scissors curve i Fig. 11. Nippers. ” Fig. 12. F Fig. 11.—Nippers; x 1; § 146. German “ Side cutting Nippers.” Fia. 12.—FInE Scissors, curved edgewise; x 1; § 156. work, as cutting cartilages and separating arthra, so as to avoid dulling and nicking the more delicate blades of the scalpels. Any thick bladed scalpel may be ground into a tolerable arthrotome. § 136. Beaded Bristles.—These are easily made. Cut from a 64 ANATOMICAL TECHNOLOGY. hair broom a bunch of the bristles, and select the longer and more perfect ones. Cut off the split end so as to leave each bristle 5-7 mm. long. Melt red sealing wax in the flame of a lamp, and dip into it the larger ends of several bristles at once; lay them down separately and dip more until each has a bit ofthe wax. Then take them one by one, hold them near the flame, and turn them between the fingers so that the wax assumes the form of a small tapering bead. These bristles are often useful in probing for slender holes and canals, especially in the brain and other soft parts. § 137. Blocks.—These are of wood, well oiled, and with the edges rounded. They are used for supporting the parts under dissection, but a folded wet towel may sometimes serve the same purpose. § 1388. Flexible Blow Pipe—Fig. 19.—This is the whole or part of the ordinary metallic blow pipe, with the addition of a piece of rubber tubing 30-40 cm. long. The blow pipe may be filed in two, and the pieces used for finer and coarser work respec- tively. Unlike the short, straight and stiff blow pipe, this may be bent in any direction, and the object inflated may be held at a con- venient distance from the eye. Since inflation is temporary injection, the advantage of witnessing the effects during the operation are obvious. A. The idea of attaching a flexible tube to the metal blow pipe was first suggested to us by Mr. C. F. Clark, a student, in 1874. B. A blow pipe of any size may be made by drawing a bit of glass tube to a point, as in making a canula, and attaching the rubber tube. § 139. Cats.—The price of cats varies from five to twenty-five cents. The owners of superfluous animals, especially of such as are too old for usefulness or comfort, are sometimes glad to have them painlessly killed. The isolated student can usually obtain a cat when it is needed, but a laboratory must keep several on hand. Contrary to general expectation, cats rarely quarrel in captivity, and the fiercest of them generally become approachable within a few days. But the fleas which probably infest all to some extent, seem to multiply more rapidly when several cats are confined together, and some persons—though comparatively few—are annoyed by them ; hence certain precautions should be observed. If possible, the cats should be kept in a separate building. If they are confined in part of a building otherwise occupied, the room should be isolated by double doors, etc. The walls should be thoroughly plastered, or made of closely matched boards. At least one window should be reached by the sun, and a raised platform should be so placed that the cats can sun themselves on it. The windows should be covered with CHAIN HOOKS. 65 strong wire netting, and always open a little at the top. In summer the ventilation cannot be too free; in winter the room should be kept at a moderate temperature (10 to 15° C.). awe once a year, the room shouid be thoroughly cleaned, and then washed with a solution of sulphate of iron. Benzine should be poured or sprayed into all the corners and cracks to kill the fleas. If possible, the room should be vacant during the hottest months. Shallow boxes of dry earth should be placed upon the floor, and the earth changed frequently. Should soiling of the floor occur, the feces should be removed at once, the spot well washed and saturated with some deodorizer, and then covered with a box. An uncleanly cat should be promptly removed. The male cat is retromingent ; if one side of the earth boxes reaches to the height of about 30 cm. (about 1 foot) above the earth, the walls of the room may be protected from their strong-smelling urine. Cats like separate beds, which may be provided by placing boxes containing a little hay or “excelsior ” along the sides of the room, preferably at a little distance from the floor. The cats are better pleased if half the top of the box is left upon it. Fresh catnip should be strewn about the room occasionally when obtainable ; the dried herb is a good substitute in the winter. Graham crackers and water should always be accessible, milk should be supplied daily, and meat once or twice a week. The milk vessels should be kept clean. § 140. Chain Hooks—(See Codman & Shurtleff, A, 43, Fig. 14). —These are used for fixing or suspending parts under dissection. In most cases, with so small an animal as the cat, these purposes can be accomplished by the use of the ‘‘small compressor,’ with strings or straps of appropriate length. § 141. Compressor, Small—Fig. 13.—This name is given to what is known among dealers in wearing apparel as the ‘Royal Garment Clasp, No. 1.” The spring which closes it is quite strong, and the sharp teeth enable it to retain its hold under considerable tension. By means of the eyelet, Frc, 13.—Smant Com. the compressor may be attached by a string or a pressor; x 1; 141, Strap to the loop at the side of the tray. For some purposes the teeth may be removed. § 142. Dissecting Gown.—In some cases, the clothes are suffi- ciently protected by an apron and pair of sleeves, or even by a towel upon the lap. But generally, especially while injecting, removing viscera, preparing bones, or performing experiments, one should wear a gown of some smooth black stuff, like sélesta. The gown should nearly reach the ankles, and the sleeves should be held at the wrists by elastic bands. It may open in front or behind, but the buttons should be concealed lest they catch upon the edge of a dish or jar. Soiling of the wristbands by the dye of the gown may be prevented by facing the sleeves with white linen. SSS Fine curved forceps. Fig. 20. ATA a : hi / Ha ih Ki | | Ih HH i (| I Tracer. Fig. I7. pipe. Fie. 19. Syringotome. Fig. 1d. Flexible blow- me ronanee forceps. Fig. [8. Figures 14-20.—Various instruments; x 1. Blunt-pointed scalpel, § 155 ; syringotome, € 161; arthrotome, § 135. tracer, § 166; coarse forceps, § 145 ; flexible blow-pipe, § 188 ; fine curved forceps, § 149. DRAWING MATERIALS. 67 § 1438. Drawing Materials—These are required in all kinds of Natural History work, and may be conveniently mentioned here. In addition to the writing pencil, there should be at least two for drawing, the one of medium, and the other of considerable hard- ness. All pencils should be ‘‘hexagonal”’ to prevent rolling, or else provided with a hexagonal rubber eraser. For the neatest work, however, it is well to use a separate eraser with a brush for removing the crumbs from the paper. (See Readers and Writers Economy Co., A.) It is so often desirable to double the size of objects that the ‘“‘duplicating dividers’? are more useful in place of or in addition to the ordinary dividers. India ink is used for some drawings and for writing upon parchment (see § 149). § 144. Drills.—A laboratory should have a foot lathe like, for example, the one figured by Goodnow & Wightman, A, 73. But most of the holes required in bone, wood or metal, may be made by a small ‘‘Hand drill,” like, for example, that figured on p. 14 of the same Catalogue. § 145. Forceps, Coarse and Fine—Figs. 18, 20.—Both pairs are absolutely necessary, and the fine ones should be curved. With nearly all forceps, the spring is too strong; it should be only suffi- cient to separate the blades when the pressure of the fingers is relaxed. If the dealers will not supply forceps with the proper spring, the desired change may be effected with a file or grindstone. The ‘Coxeter’? style of coarse forceps is to be preferred. Those represented in Fig. 18, have the blades excavated so as to be lighter than those formerly made. § 146. Nippers— Fig. 10, 11.—These are the “diagonal side cutting nippers or pliers”? of the dealers in hardware. The obli- quity of the blades to the handles gives them great advantages over either the ‘‘side cutting”’ pliers, or the ‘‘cross cutting,’ which are shown in Fig. 10, left figure. Seven sizes are made, ranging from 10-20 cm. (4-8 in.) in length. Those of 10 and 15 cm. are best adapted to anatomical work upon small animals. The larger of these will cut any of the bones of cats less than two years old, but the larger bones of older individuals may require the saw. For some purposes the points should be quite sharp, and may be made so with a file or upon a grindstone. A. “Pointed nippers with oblique jaws” are mentioncd by Newton (B, 22, 174), but they do not appear to be in genera] use by anatomists. The nippers have been used in anatomical work, especially for the removal of the brain, by the senior author since i871, and are mentioned in his paper, 21, 158. 68 ANATOMICAL TECHNOLOGY. B. The German instruments answer very well for most purpcscs, and are much lers expensive than the others. They are imported by Messrs. H. Boker & Co., of New York, and may be had of A. J. Wilkinson in Boston, and of Messrs. Treman, King & Co. in Ithaca, and of larger dealers generally. The ‘“ Stubs’s” nippers are more finely tempered, and better finished. The smallest size (Fig. 10) are sold by Messrs. Codman & Shurtleff for $1. The “bone forceps” of the surgical price lists are still more expensive, C. The “cross cutting” nippers are employed chiefly for cutting wire and for other mechanical purposes. § 147. Oiler.—A neat substitute for the ordinary metal oiler may be made by suspending a dropping-tube in the mouth of a vial of oil. One may then graduate the amount more exactly, and apply it more accurately ; see Appendix. § 148. Parchment Numbers.—Sheets of numbers of any size may be had ata reasonable rate from ‘Collins’ Printing House,” Philadelphia. Ifthey are to be used with alcoholic specimens, that fact should be mentioned so that proper drying ink may be em- ployed. The numbers may be pasted upon dry specimens, or placed in the alcohol with wet ones, or attached to muscles during dissection by means of the small ‘ribbon pins.” § 149. Parchment for Labels.— Numbers and memoranda to be attached to alcoholic specimens should be written upon parchment with a saturated solution of India ink in either glacial acetic acid, or acetic acid No. 8. The writing should be allowed to dry before exposure to the alcohol. Parchment is written upon more easily if the surface is first rubbed with a rubber eraser. § 150. Rubber Gloves.—These are an efficient protection against contact with poisonous or malodorous substances. Of course, fine dissection cannot be done in gloves, but it is sometimes desirable to protect the hands, especially in the manipulation of the intestines, and while macerating bones. Like other rubber articles, the gloves should be wiped dry after using, and laid in a cool, dark place. § 151. Rubber Tubing.—For the blow pipe, and for canule, the lumen should be 3 mm. (1-8th inch); the size next most use- ful in the laboratory is 6 mm. § 152. Saw—Fig. 21—This should have a thin blade, and the teeth should be but slightly ‘set.’ It is used chiefly for bisecting the head for the removal of the brain, and should not be employed for . 2 / a mechanical purposes. . a § 153. Scales.—Very few cats BE VE BeOS Ey O05 weigh as much as 5 kilos., and heavier ones can be weighed entire ENTE WEIGHING PAN, 69 upon ordinary scales. For most anatomical purposes, therefore, the scales need not be arranged for more than 4-5 kilos., or about 10 lbs. avoir. Weights of less than 1 gram should be determined by the smaller or ‘‘ prescription”’ scales. Of the larger scales there are two styles, the ‘‘ open” and the “box.” An example of the former is the ‘‘ Druggist’s trip scales,” figured by J. & H. Berge, A, 63; of the latter, is the “ Ebony box scale,” figured by Whitall, Tatum & Co., A, 74. With a capacity of 10 lbs., the former costs $7, and the latter $14. In selecting scales, it would be well to obtain the advice of some chemist or physicist. § 154. Weighing Pan.—The scale pans accompanying the scales above mentioned are about 20 cm. in diameter, and will contain any separate organ of the cat, or the head or limbs. For weighing an adult cat entire, a larger pan is needed. For this purpose, one of the ordinary trays, 30x40 cm. may be used, but it is better to pro- vide a special pan. It should be oval or oblong, about 25 x 35 cm., made of stout tin, and with a rim about 3 cm. high. Its weight may be diminished by punching out disks not more than 1 cm. in diameter, until it exactly balances some weight, as 500 grams, or a piece of lead, which, of course, must be used always with the pan. Ifthe cat to be weighed is stiff, it may sometimes be made to rest upon the ordinary scale pan without touching anything ; other- wise this special pan should be used, the arms and legs and tail being kept within it. § 155. Scalpels—Figs. 22, 23, 24.—These are single edged, and thin bladed knives, with ebony or ivory handles. The medium size Fig. 22. BosTON Fie. 23. Fie. 24. GODMANASHURTLEFF CODMANASMUATLEFR. boson Fig. 22—LarcE ScaLPeL, for sections of brain, etc.; § 155; x.5. Fic. 23,—Mzprum- SIZED SCALPEL, for ordinary dissecting; x .5; $ 155. Fic. 24.—CHARRIERE ScALPEL, for finer dissecting ; x .5; § 155. (Fig. 23) answers for most purposes, and will last a long time if care- fully used. The ‘‘Charriere”? is employed for finer—but not the finest—dissecting, and the large scalpel should be kept perfectly smooth and keen for making macroscopic sections of the brain, heart, etc. vi) ANATOMICAL TECHNOLOGY. 8 156. Scissors—Figures 12, 25.—All dissecting scissors should be curved. The curvature gives three advantages: better adap- tation to the surfaces of animals and their parts, , = which are rarely plane; eee “\ the power to change the aor tua” direction of the cut with- Fig. 25.—CoarsE Scissors CURVED FLATWISE; out corresponding move- x.5; § 156. ment of the hand or of the subject; the effect of the cutting is more easily observed. For most purposes, the blades should be curved flatwise, as in Fig. 25, but those curved edgewise, as in Fig. 12, are sometimes very con- venient. All coarse scissors should have lock joints, so that the blades may be separated for cleaning and sharpening. ine scissors should have sharp and well matched points. The mediwm coarse scissors are well adapted to work upon the brain and heart, and other organs for which the coarse scissors are too large, and the fine ones unnecessarily delicate. § 157. The bone scissors are simply a strong, blunt-pointed pair of coarse scissors, with which the cartilages, ribs, and other hard or tough parts may be cut, so as to save the edges of the proper dissecting scissors. .A straight pair will answer the purpose quite well, and usually cost somewhat less. § 158. The hair may be removed with a pair of common cheap scissors; but it is better, especially in a large laboratory, to provide a special pair of coarse scissors, curved flatwise, and with the points quite blunt. § 159. The enterotome supplied in post-mortem cases is a pair of long scissors, one blade of which is enlarged and rounded, and projects beyond the other so as to precede it in opening an intestine. Similar instruments might be made for the cat, but the same end may be accomplished by guarding one of the blades of a pair of coarse scissors, especially such as are curved edgewise. Cleland suggests (A, 155) sticking a bit of costicartilage upon one blade, but a small rubber stopper will serve the purpose. § 160. Sponges.—Sponges may be conveniently classed as car- riage, bathing, anatomical and surgical. The last are fine grained, and specially prepared, so as to be somewhat expensive. A few such, of conical shape, are desirable, especially for experimentation. For ordinary anatomical purposes, sponges should be small enough THE SYRINGOTOME. val to be easily grasped, and should be freed from sand and grit before using. The larger and coarser kinds are useful in various ways. All sponges should be washed after using, and boiled occasion- ally for a few moments. Itis said that they may be freshened by soaking in brine to which a little iodine has been added. § 161. Syringotome—Fig. 15.—This is sometimes called ‘‘can- aliculus knife.’ It is a small, concave, blunt pointed bistoury, which is very convenient for delicate work upon the brain and heart, and for following and slitting up narrow canals. The syringotome was found very serviceable by the senior author in tracing out the tortuous canals upon the heads of sharks and skates at the Museum of Comparative Zoology in 1866-7. At his suggestion it was included in the set of dissecting instruments supplied to the students of ‘The Anderson School of Natural History at Penikese Island ” in 1873. Excepting with the brain, however, most of the uses of the syringotome may be subserved by the less expensive tracer. § 162. Tags.—Two sizes of tags are needed: the smaller are for numbers or brief memoranda sufficient to identify the specimen ; they are used by stationers and dry goods dealers. The larger are the smallest size of ‘‘ Dennison’s Shipping tag,’”’ and are 3.5 cm. wide by 7.2 long; they should be provided with strings, and the eyelet should be guarded by a metal ring. § 163. Tenaculum—See Codman & Shurtleff, A, 42, Fig. 8.— This is seldom needed in felitomy. § 164. Tools, Carpenter’s.—A laboratory should contain the ordinary tools, as saw, hammer, screw drivers, awls, bits and stock, rat tail and three cornered files, screw hooks and eyes, etc. § 165. Towels.—Excepting the roller towels, these should be short. The finer crash is more expensive, but wears longer than the cheaper stuffs, and there is less lint; it may be had in rolls, which may be cut into the desired lengths. § 166. Tracer—Fig. 17.—This is prepared from a piece of hex- agonal or octagonal steel rod, about 15 cm. long, and 4 mm. in diameter. The middle third is left as a handle; one of the terminal thirds tapers to a blunt point, and serves as a probe for some purposes ; the other end tapers in like manner, and is bent at the tip so as to form about the fourth of the periphery of a circle 1 cm. in diameter ; the concavity is then sharpened. The value of the tracer in isolating vessels and nerves can hardly be overestimated. A dull tracer may be used also in lifting vessels and nerves that have been isolated already, as in experiments. 92 ANATOMICAL TECHNOLOGY. A. A tracer may be made by any one from a piece of steel rod, or from a dental ‘‘ exca- vator,” but the saving so effected is hardly worth the trouble. The instrumentis made by Codman & Shurtleff, and perhaps by others. B. The tracer is apparently similar to the “seeker” of the English anatomists, and the “finder” of the Germans. The instrument was introduced into the laboratory of Cornell University with a microscope presented by the late Hon. John Stanton Gould. The con- version of the opposite end into a tapering probe was suggested by Mr. Willis N. Rudd, a student, and the sharpening of the concavity was first proposed by the junior author. § 167. Trays—Fig. 78.—These are usually made of stout tin, but copper is more durable. If wood is used, it should be thoroughly oiled. A wire loop should be soldered at the middle of each end, and on each side at about one-sixth of the distance from each end. Four sizes of trays are convenient in the dissection of cats: 15 x20, 20x30, 30x40, and 40x60cm. The depth of the two smaller sizes should be about 1 cm., and that of the two larger about 2cm. The largest size should be stiffened by diagonals upon the bottom. § 168. Tripod Magnifier—Fig. 26.—This is a simple magnifier with a large field, and mounted upon a tripod which may be placed Cc e2ik R <5 33 diocese on do sere Saree Ie C Fie. 26.—TRIPOD MAGNIFIER; x 1; § 168. Fig. 27.—WeETT1nG BoTTLe; § 170. in liquid. While examining delicate objects out of liquid, it is safer to turn the legs toward the eye, or remove them altogether. The object should be held so as to receive the best light. § 169. Tunnels.—Several sizes are desirable, of both glass and tin. The latter should have the slender part fluted. When the larger part of a tin tunnel, or either part of a glass one, is set into a bottle or jar, a thick string should be interposed between it and the mouth of the vessel to permit the escape of air as the liquid enters. WASTE PAPERS. "3 § 170. Wetting Bottle—Fig. 27.—The bottle is about 16 x5 cm., so as not to be easily overturned. The mouth is closed by a cork through which are passed two slender glass tubes. One, the air- tube, is straight, and reaches nearly to the bottom of the bottle ; the other, the spout, extends but little below the cork, and is curved so as to permit the ready application of the contents. § 171. Wetting Mixture.—The cheaper commercial glycerin is to be mixed with water in the proportion of 15 per cent. by measure, or 12 per cent. by weight, and about 25 drops of clove oil is to be added to each liter of the mixture. § 172. Waste Papers.—These are pieces of paper of several sizes, corresponding respectively to the slips, the sheets, and the trays, The quality of paper is not material, so long as it is firm enough to hold together when slightly wet. The ‘‘roll Manilla” paper of medium thickness is strong and cheap, but the ordinary slips and sheets which have been used by writing on one or both sides may be kept for this purpose. With fine dissections, or when only connective tissue or small muscles are to be removed, the waste slip may be placed in a corner of the tray. With coarser work, and when skin, fat, and the larger muscles or viscera are to be removed, use the waste sheet. When the cat is to be transected or eviscerated, or when some larger animal is under dissection, have at hand extra trays contain- ing the corresponding waste papers. The waste should be disposed of as soon as possible, but in case the opportunity for re-examination is desired, the tray containing it may be set aside, and the paper will obviate the objectionable adhesion of the waste to the tray itself which might otherwise occur. CARE OF INSTRUMENTS. § 173. In general, all instruments should be washed, thoroughly dried, and slightly oiled as soon as possible after using. The washing may be done with a cloth or sponge, but the nail brush should be used for the joints of nippers, and the teeth of the saw. The wiping may be done with a towel, and then with a bit of clota or chamois slightly oiled. All joints should be kept well oiled or vaselined. G4 ANATOMICAL TECHNOLOGY. The oiling should be especially thorough when instruments are to be packed away or disused for some time, and particularly at the sea shore. Scalpels and other instruments with wooden or ivory handles should not be allowed to soak in water, lest the rivets become loose after drying. Wooden handles should be occasionally oiled. 8 174. Blow Pipe.—Usually this needs only to be wiped, first with a moist, and then with a dry cloth. After using, be sure that the lumen is free; if clogged, open it with the fine knitting needle, or a wire. § 175. Forceps.—Clean the serrated parts with the nail brush, draw a cloth or towel between the blades, and then wipe. § 176. Nippers.—Clean the joint and blades well with the nail brush, wipe dry, and oil the joint. § 177. Saw.—Use the nail brush, moving it from the back to- ‘ward the teeth. Wipe, carrying the towel in the same direction. Then wipe dry, and oil. § 178. Scalpels and Cutting Instruments Generally.—These instruments, and especially such as have keen edges and delicate points, should be protected from contact with each other and with other objects. If not kept in a case, they may be laid in a small tray, like the cover of a note box lined with chamois or velveteen. When several are to be carried at once, each handle should be held between two fingers so that the blades may not touch. In wiping a scalpel, hold it firmly in the left hand, and let the cloth cover the right thumb and index, as in wiping a table knife ; do not let the cloth come upon the edge. The scalpel should be wiped four times: first with a moist cloth to remove all blood and fragments; then with a dry cloth; then with an oiled cloth or chamois, and finally with a clean dry cloth or chamois. The fingers should not touch the blade after the final wiping. § 179. Scissors.—If the blades are lock jointed, they should be separated. The blades are to be treated like the scalpels. Clean the joint thoroughly, and keep it oiled. § 180. Trays.—If waste papers are used, the trays will usually require only rinsing, after which they should be set up on edge to dry. Where many trays are used, there should be a suitable rack for them. § 181. Instrument Cases.—The experienced anatomist rarely uses the ‘“‘case’”? in which, probably, his first instruments were PACKING INSTRUMENTS FOR TRANSPORTATION. © 95 purchased. The ordinary case never has room for all the neces- sary instruments, and is a less convenient receptacle for them while in use than a shallow tray like the cover of a note box; see § 110. If the student is unable to resist the temptation to possess a regular dissecting case, he is advised to obtain one of the more costly, as likely to contain better instruments. The case commonly selected by the special students at Cornell University is sold by Messrs. Schuyler & Co. and White & Burdick, of Ithaca, for $6.25. It contains the following instruments: three assorted scaipels, coarse and fine forceps, coarse and fine scissors, arthrotome, tracer and blow pipe. Similar cases may probably be had elsewhere. The additional instruments must be purchased separately. ; § 182. Packing Instruments for Transportation.—All scalpels and delicate pointed instruments generally should be packed as follows: thrust the point into a bit of cork, then wrap well in a. piece of thin paper, such as is supplied in packages under the name of ‘“‘star mills,” “diamond,” etc. The paper should project well beyond the blade, and be twisted or bent over so as to keep the cork in place. Thus wrapped, the most delicate instruments may be sent by mail in pasteboard or light wooden boxes, or otherwise transported. Since no written communication is permitted upon such a package without payment of letter rates, the consignee should be notified at the same time. Whether for mailing or any other kind of transportation, the heavier instruments, or such as need no special protection, should be packed separately from the more delicate. Small cigar boxes answer a good purpose, but the most suitable boxes for instruments are made by the Swift Manu- facturing Co. of New York, and others; they are long and narrow, and provided with lids. POLISHING INSTRUMENTS. § 183. A. Instruments that have become tarnished may be re- polished by rubbing with a piece of chamois or cloth on which has been put oil and rouge. Perhaps the best way to apply the polish- ing material is to wrap the cloth around the end of the index for small instruments, or roll the cloth or chamois into a bundle for large instruments. In both cases the surface to be polished is rubbed as in scouring household knives, taking care to avoid con- tact with the edge of the instrument. 76 ANATOMICAL TECHNOLOGY, B. Rust should be removed with a dull knife and then the polishing may be done as above. When an instrument is badly tarnished, the polishing with rouge is a tedious process. In that case, fine emery may be used to remove the tarnish, and then rouge for the final polish. The emery should be applied as directed for rouge. C. If one has access to a polishing wheel the process is shortened greatly. The same materials are used as in polishing by hand and in the same order. D. Emery of exceeding fineness may be easily prepared as follows: Fill a high narrow vessel like a preserving jar, nearly full of water, and put into it about 200 grammes of ordinary flour of emery. Agitate thoroughly, and after the vessel has stood half a minute pour off the liquid into another dish. Add more water to the first vessel and agitate again, and pour off the liquid as before. The larger particles sink first, and hence the emery in the water poured off is much finer than that left. Allow the emery to settle from the first and second washings and pour off the water and dry the emery. Several grades may be obtained in this simple way. E. "Instruments may be very nicely polished by using, in place of rouge, the fine whitish ashes that may be found in the upper parts of stoves in which anthracite coal is burned. F. If rouge is added to the oiled leather used for wiping the instruments after they are washed (§ 178), the polish may be retained indefinitely. SHARPENING INSTRUMENTS. § 184. Honing.—For honing, it is desirable to have two oil stones, one very fine for finishing, and one somewhat coarser for Turning knife. any if ee) ara Honing. Stropping. [ OL stone. Fig 28.—Honinc AnD Srroprine Knives. The upper figure shows how the knife is to be turned upon its back in reversing the movement. The left figure shows the edgeward movement of the blade in honing; the right, the backward movement in stropping. §§ 184, 185. HONING. 77 commencing the sharpening, and for sharpening the coarser instru- ments. A. Place several drops of fine olive or sewing-machine oil on the stone and, with a cloth devoted to the purpose, rub the surface to remove all dirt and expose the cutting particles of the stone. After the stone is well wiped, put two or three more drops of oil upon it, and spread it around with a scalpel blade. B. Look at the edge of the instrument to be sharpened with the tripod magnifier, holding the edge of the blade up and between the eye and the light. This is to see if there are any nicks in the edge. If there are nicks, they should be removed by rubbing the edge on the fine stone. After making two or three sweeps across the stone, look at the edge again to see if all the nicks are removed. If they are not, continue to grind the edge on the stone till they are. Ifthe nicks are slight the edge need be ground off only in their immediate vicinity. If they are deep, however, the entire edge should be re- moved or it will become wavy. When the edge is smooth and free from nicks it should be honed ; if quite dull, first on the coarse and then on the fine stone. C. In case the instrument is a scalpel, (1) grasp the handle in such a way that the index and medius shall oppose the pollex, and the end of the handle shall touch the palm. (2) Place the blade flat on the stone as shown in Fig. 28, and then lift the back very slightly. (8) Move the knife with a curving sweep toward the left, as shown by the arrow, so that the point of the blade shall be at the lower left corner at the end of the sweep. (4) Then turn the blade over, always turning the edge away from the stone. Do this by rolling the handle in the fingers. (5) After the knife is turned, it should be moved across the stone from left to right exactly as described for the motion from right to left. The handle, of course, points in the opposite direction. In this method of honing, which is that employed by the best cutlers, the edge precedes the back; the blade is so placed on the stone that it follows the handle, and the sharpening is from heel to point. If the blade were pushed across the stone instead of being drawn as above, the sharpening would be from point to heel. D. In the beginning of the honing, one may press quite firmly and draw the same side of the blade over the stone three or four times without turning it; but when the edge becomes thin, the blade should be turned at every sweep. 78 ANATOMICAL TECHNOLOGY. E. In case the edge should turn over, producing the so-called wire edge, it must be removed by drawing the edge along some fine- grained substance like horn or ebony. One should be careful not to get any of the detached wire edge on the stone, as it would be liable to produce nicks in the edge of the knife. F. (1) Use the coarse stone until the knife will cut a thin shaving from the convex surface of smooth writing paper. (2) Wrap the paper around a lead pencil, remove the pencil and rest the blade flat upon the paper. Press down slightly, and push the blade, edge forward, along the top of the curve. If the knife is sharp, it will cut a thin shaving from the paper. (8) Another very excellent way to judge of moderate sharpness is to rest the tang of the blade on the end of the medius, and to feel of the edge by moving the ball of the index along it in such a way that if a cut were made it would be a mere shaving from the cuticle like that from the paper. If the knife is sharp, it will take hold, as it is called, that is, one can feel that it is cutting. The ball of the index is very sensitive, * and one can judge quite correctly of the smoothness and sharpness of the edge. Those who object to trying the edge on,the skin can employ a bit of smooth grained cork. G. (1) When the edge is sufficiently sharp throughout its entire extent to cut a shaving from the cylindrical paper, or to take hold of the finger or the edge of the cork, the fine stone may be used. (2) In using the fine stone the blade should be turned at every sweep. Use the fine stone until the knife will cut a hair near its base or near the point where it is held. (3) It often happens that some parts of an edge are sharp and others not. In sucha case the dull parts alone can be applied to the stone by using the edge of the stone. When the scalpel will cut a hair close to a fixed point, it is sufficiently sharp for ordinary dissecting. § 185. Stropping.—A good razor strop is required, as, e. g., “ Emersons’.”’ The strop is to give the final keenness and smoothness to the edge of a cutting instrument. It is a waste of time to employ it before the degree of sharpness indicated for the fine stone is attained, as the strop sharpens very slowly. A. (1) Grasp the knife exactly as for honing. (2) The blade is carried across the strop with a long curving sweep just as de- scribed for honing except that the back of the blade precedes the KILLING ANIMALS FOR DISSECTION. 79 edge. (Fig. 28.) (8) The blade ‘should be turned at the end of every sweep across the strop, thus drawing it from right to left as often as it is drawn from left to right. B. (1) Use first the red and then the black side of the strop. (2) Press only moderately. The nearer a perfect edge is attained the more lightly should one press. (3) Continue the stropping on the red side until the knife will cut a hair of the head 1 cm. from the point where it is grasped by the fingers ; then employ the black side. (4) Continue to use this side until the knife will cut a hair from the head 2-3 em. from the point where it is held, or, what is a better test, until it will cut the fine hairs on the dorsum of the hand and wrist half a centimeter from their base when the Knife is moved distad—toward the ends of the fingers. If the knife has a perfect edge it will cut these fine hairs so easily that one can hardly tell by the feeling when a hair is divided. § 186. Scissors.—These are much more difficult to sharpen than scalpels, and the fine ones should be sent to the makers unless one is very skillful. Place the blade so that the oblique face formed by grinding shall rest flat on the stone. Draw the blade, edge foremost, across the stone with a curving sweep as for scalpels (§ 184, C [3] ). Test for sharpness with the finger or by attempting to cut moistened tissue paper (§ 184, F [8] ). § 187. Tracer, Syringotome and Concave Edges Generally.— In sharpening instruments of this kind one should use the edge of the stone instead of its face. The edge of the stone should be some- what rounded. In sharpening, draw the blade along the stone so that the edge precedes the back as for scalpels (§ 184, C [8] ). Test the sharpness with the finger (§ 184, F [3] ). § 188. The care and sharpening of instruments are considered by Mojsisovics, A, 18 ; Holtzapffel, A, III, 1026-1156; Hyrtl, A, 23-27; Straus-Durckheim, B, 1, 158-160. KILLING ANIMALS FOR DISSECTION. § 189. There is usually no difficulty in taking a cat when it is wanted. Such as will not come when called may be secured by means of a strong net, or by using a bag attached like a net toa hoop and pole. The bag referred to is of strong coarse material, and commonly used for oats. In such a bag the cat may be left for several hours; 80 ANATOMICAL TECHNOLOGY. but the closer-woven bags which“*are used for flour do not admit sufficient air. § 160. Methods of Killing—(Bernard, A, 149-182).—Two things are to be considered in killing animals for dissection :— (1.) The death should be as nearly painless as possible. (2.) None of the organs or tissues to be examined should be injured by the method employed. § 191. Drowning fulfils the above requirements fairly well. Judging from the experience of human beings, death by drowning is attended with very brief physical discomfort. Place the cat in a wire cage, or loose meshed bag, and immerse it completely in water for four or five minutes. Usually a cat can- not be resuscitated after it has been completely immersed for ninety seconds; after four or five minutes, spontaneous resuscitation is altogether improbable. § 192. Chloroforming is preferable to drowning, since no liquid is drawn into the lungs, and the hair is not filled with water. The death, too, with cats, seems to be quietly going to sleep. There is usually no struggling, showing that the period of intoxication by the chloroform is very short. Place the cat in the anesthetic box (see Fig. 29). This is easily accomplished if the cat is in a bag by placing the mouth of the bag in the box, whereupon the cat will usually walk in of its own accord. After the cat is in the box and the door closed and fastened, remove the cork from the hole in the edge and pour 5-10 cc. of chloroform upon the furled curtain. Then unfurl the curtain by means of the string ; this will expose a greater surface from which the chloroform can evaporate. Usually the cat will be asleep in three minutes, and dead in twenty minutes. Do not remove it from the box till all signs of respiration have ceased. If ether is used, 15-20 cc. is required for a cat. A. If one does not possess the anesthetic box, cats may be chloroformed as follows: Place a newspaper on the floor, and invert over it a large wash-bowl] or a small tight box or pail. Put the cat under the receptacle, and pour 10 cc. of chloroform on a sponge or a bit of cotton, and put it under the receptacle with the cat. The box, or whatever is used, must be held down, ora weight must be placed upon it, while the animal is coming under the influence of the anesthetic. _ B. Dogs moan while becoming anesthetized, but presumably they and all other ani- mals may be killed painlessly with chloroform or ether. The amount required to kill an animal varies with its size, and with the size and closeness of the box. § 193. Killing Fleas.—If the cat has fleas, as is usually the case, PRECAUTIONS FOR CLEANLINESS, ETC. 81 open the box after fifteen minutes, and throw over it 20 cc. of ben- zine. Reclose the door of the box and leave it for ten or fifteen minutes longer. Fleas revive from the chloroform used in killing the cat, but they do not revive if benzine is used. Do not use the benzine until the cat is completely anesthetized, for it causes great discomfort. § 194. The Anesthetic Box—Fig. 29.—This is a close box, the base, frame and door being of wood, and the rest of ‘‘ double-thick”’ | ald fetes cor ietecy i TN q Curtatn' e \ + doom . x/ 2 19X17 = = base Sx09 \ Fie. 29.—THe ANASTHETIC-BOX; x .1. glass. The dimensions are given in the figure. The base and frame should be grooved for the reception of the glass, and the whole should be put together with screws to permit the renewal of the glass in case of breakage. Along one side, near the top, runs a thick brass wire, on which slides a curtain, moved by a string. Just above the curtain, when furled, is a hole, which is closed by a cork secured from loss by a string. The leather handle is convenient in lifting and moving the box. The cost of the cat-box, including the glass, is about $1.50. Almost any close vessel or box will answer for the administra- tion of a fatal dose of chloroform, but for experimental purposes the progress of anzesthesia must be observed. PRECAUTIONS FOR CLEANLINESS, COMFORT AND HEALTH. § 195. Waste Papers.—These have been referred to in § 172, and are mentioned here again because of the tendency of beginners to neglect a very essential element of neatness in anatomical work. § 196. Waste Pail.—This should be of galvanized iron, copper 6 82 ANATOMICAL TECHNOLOGY. or zine, never of wood or tin ware. The cover should be of the same material, and fit closely. The pail should be emptied at night, rinsed, and a few cc. of permanganate of potash solution poured into it. Once a week it should be thoroughly scoured and dried. § 196. Waste Pit.—The single student may readily dispose of the refuse of his work, but some special provision must be made for a laboratory. In cities, communication may sometimes be had with the sewer. The opening into the sewer should have at least two lids, closely fitting, and should be within a closet or cupboard provided with a special flue so that the sewer gas may not be drawn into the labo- ratory. In smaller towns, and at many universities, the readiest mode of disposal of refuse is to have a pit dug in dry soil at a convenient distance. The mouth of the pit should be kept from falling in by a cask or box, and should be closely covered. The earth removed in digging the pit should be kept at hand under cover, and some of it sprinkled over the offal at night. When filled within half a meter of the surface, the pit should be filled up compactly with earth. § 197. Sink.—This should be of iron, galvanized iron, zinc or copper, or lined with one of these materials. It should be slightly inclined, the outlet should be at the lower end, and guarded with a movable grating. The escape-pipe should be of ample size, and trapped at some point which can be reached. Excepting just over the escape, the sink should be covered by one or more wooden lids on hinges which may be raised from the front and rested against the wall behind the sink. These lids should be of hard wood, and well oiled or painted. In each lid should be cut an oval or elliptical hole for a basin. The longer diameter of the hole should correspond with that of the sink, so that the basin may be emptied without lifting it from its place. If there is no general water supply, a water cask or lead lined box may be placed above the sink. In any case, the faucets should be nearly on a level with the face of one standing at the sink, and the water should be conducted therefrom through flexible rubber tubes ending a little above the basin. The tube must be firmly secured to the faucet, and must not be sharply bent if the pressure of water is considerable. DEODORIZERS. 83 Hair, plaster of Parts, sand, and jine particles generally must not be thrown in the sink. The sink should be thoroughly emptied and washed at night. A convenient instrument for scraping out the sink, or cleaning a table or tray, is a piece of heavy rubber moulding, provided with a handle. § 198. Deodorizers.—Most of the unpleasant smells which would otherwise attend work in practical anatomy may be avoided by preserving the material in alcohol, by removing the intestines within twenty-four hours after death, and by the observance of other due precautions for cleanliness. But maceration is necessarily offensive, and sometimes valuable specimens are more or less de- composed before their reception; it is therefore necessary in some cases to employ deodorizers. Animal Charcoal.—This effective deodorizer may be sprinkled over the surface of offensive specimens, and is especially service- able when such have to be transported. Its use in the improve- ment of old alcohol is described in Ch. III. Alcohol.—If the specimen is of moderate size, and is to be pre- served as a whole or in great part, the putrefaction may be checked by immersion in strong alcohol, from 75 to 95 per cent. The alcohol may be poured over the specimen, or the latter may be immersed in it, or covered by cloths saturated with it. In either case, the alcohol will become offensive, and must be deodorized by filtration before mixing with other alcohol or use upon other specimens. The stronger the alcohol, the more decided is its action, but its clearness is unessential. Potassium Permanganas.—This is an excellent deodorizer. A saturated solution should be kept at hand, and a few cc. poured into the waste pail at night, and into any other malodorous jar or vessel. It stains the skin temporarily. Sulphate of Iron—Copperas.—This cheap deodorizer may be used in place of the more efficacious but more expensive perman- ganate of potash. The coarsely powdered crystals, or a saturated solution, may be placed in the sink, pail, or pit. A solution of Chloride of Lead is recommended in The Medical Record, August 20, 1881, p. 222. § 199. Discharges from the Cat.—The following precautions are always desirable, and should never be neglected in demonstra- tions or experiments upon cats before a class :— 84 ANATOMICAL TECHNOLOGY. When the cat is dead, or, in experiment, quite asleep, place it upona tray. Roll some common cotton between the fingers into a somewhat firm conical plug or suppository about 5 x1 cm. Dorsiduct the tail of the cat so as to expose the anus and open it slightly. With the large forceps grasp the plug obliquely near the tip and force it into the rectum. Then push it completely beyond the constricted orifice with the forceps or a smooth, rounded stick. Ifthe cat has been affected by diarrhea, it may be necessary te insert a second plug. Let the buttocks of the cat project slightly beyond the edge of the tray, over the sink or some other receptacle ; then press firmly and steadily upon the abdomen just cephalad of the pubes. If the cat is a female, the urine will usually flow out readily; if it does not appear, as is often the case with males, it is not likely to be forced out during the subsequent operations. The urine of cats has a very offensive odor, and should not be allowed to flow into the tray, or to reach the hair of the animal. Remove any escaped urine or feces with a bit of cotton, followed by washing if necessary. If the left hypochondrium is prominent, or if there is other evidence that the stomach is distended with food, let the mouth pro- ject beyond the tray over a receptacle, and compress the whole abdomen. If any matters escape from the stomach, the mouth should be washed afterward with a stream of water. § 200. Malodorous Parts.—On account of their contents, the stomach and intestine become offensive very soon after death, espe- cially if exposed to the air. In some cases it may not be necessary to open the abdomen during the dissection of a fresh specimen ; decomposition will then proceed less rapidly, and the effects will be less obvious. If the abdomen is opened, these hollow viscera should be either removed soon, or so treated as to lessen or prevent the production of offensive odors. The large intestine especially may usually be examined during the first or second day, so as to be removed. When any part of the alimentary canal is divided, the site of the intended incision should be freed from its contents for at least 2cm.; then two ligatures should be applied at least 1 cm. apart, and the cut made between them ; see Fig. 41. When it is undesirable to remove the intestine, most of the offensiveness may be avoided by expelling the contents. The con- DISSECTION WOUNDS. 85 tents of the large intestine are readily forced out by manipulation, the cotton plug of course having been removed. Those of the small intestine may be made to flow out with a stream of water injected into it near the stomach by means of a syringe, or from a faucet. The water should be pressed out of the intestine, and alcohol then thrown into it. The alcohol may be retained if the plug is returned to the anus; ora ligature may be placed about the rectum. § 201. Dissection Wounds.—Slight dissection wounds have oc- casionally been received in the anatomical laboratory of Cornell University, but the results have been nowise different from similar cuts inflicted under ordinary circumstances. So far as our experience goes, it is probable that no danger need be apprehended from a wound received during the dissection of any well preserved alcoholic specimen, or of any healthy cat, whether fresh or otherwise. In proportion to the number of human bodies annually dissected or examined in necropsies, serious dissection wounds are very few. Indeed, the actual number of such cases is so small that statistics are wanting to enable us to determine with accuracy the conditions under which the consequences are likely to be injurious. A few writers believe these results to be due to “the absorption and irritation of a putrescent fluid ; but this explanation will hardly account for the frequency of the disease after contact with recent bodies before putrefaction has set in, and especially of persons who have died of acute disease, such as puerperal fever, peritonitis, etc., and for the affection of several per- sons at the same time, from the same body and with the same symptoms.” In view of the insufficiency of our knowledge, and of the fact that dissection wounds are most apt to occur with beginners, one of the advantages of the cat as a subject of pre- liminary anatomical work is, that the subject may be obtained healthy and fresh, and be preserved in alcohol at slight expense. § 202. Precautions.—Dissection wounds should be avoided by care in the use of cutting and pointed instruments, and by guard- ing against contact with the sharp points and edges of bones which have been broken or cut. Before commencing work upon a suspected animal, or upon decomposing flesh, or upon macerated bones, the hands may be anointed with some kind of fat, as cosmoline, vaseline, olive oil or “cold cream.”’ If the skin is already broken, rubber gloves may be worn, as in macerating or in handling offensive viscera, etc., where no delicacy of manipulation is required. In ordinary dissection upon a suspected subject, the cuts or abrasions may be cauterized with strong carbolic or nitric acid, or covered by several thicknesses of adhesive plaster. 86 ANATOMICAL TECHNOLOGY. If the hands can be kept dry, the common court plaster or isin- glass plaster will suffice; but if they are to be wet, it is safer to use the diachylon or lead-plaster, which does not easily wash off, but must be warmed before application or removal. In cauterizing, use a slender, pointed stick ; dip it first into the acid, and then into the open place of the skin. § 203. Treatment.—“ Local applications, if used at all, must be employed immediately, decisively, and effectually. Should a per- son be in bad health at the time of receiving a prick or wound during dissection, no matter what condition the subject may be in, it behoves him to pay immediate attention to the injury, and anti- cipate any further consequences.” “Should the wound be received while engaged on a recent sub- ject, and one which had died from acute disease, much more caution and attention are required, even if he be in the best of health. The part should be well cleansed, and a temporary liga- ture applied immediately above (centrad of) the wound; then the bleeding, if any, should be encouraged to flow freely ; where there is no bleeding, suction must be employed; [this may be by the mouth if the skin and mucous membrane are intact, otherwise by means of a tube, or, better, a cupping glass the exhaustion of which is produced by means of a rubber bulb].”” Then cauterize as directed above. The foregoing directions for immediate treatment are taken from Holmes (T.) A, 621, and Clarke, A, 54. Whenever ill effects are anticipated, proper medical advice should be sought without delay. CHAPTER II. GENERAL DESCRIPTION OF THE SKELETON—ANATOMICAL LANDMARKS—ABDOMINAL TRANSECTION. GENERAL DESCRIPTION OF THE SKELETON, § 204. The softer parts of the body are protected, supported, or enabled to exert themselves to greater mechanical advantage by a framework—the skeleton. The skeleton consists of bones (Ossa), and cartilages (Cartila- gines), which are more or less closely united at sutures (Sutur@), or movable upon each other at Arthra (joints or articulations). At the arthra and at some of the sutures the undesirable displacement of the parts is checked by bands of inelastic fibrous tissue—the liga- ments (Ligamenta). Firmer in texture, more definite in outline, and more constant in form, number and position than most of the soft parts, the bones and cartilages serve as convenient guides to the identification and description of the latter, and therefore naturally precede them as subjects of anatomical study. The following general account of the skeleton as a whole is given in advance of the detailed description of the individual bones in order that the directions for certain preliminary operations may be more easily understood and followed. § 205. Fig. 30.—The skeleton seen from the left. This figure has been reduced by photography from that of Straus-Durckheim (A, Pl. 11), and has been further modified as follows: the dextral cost (ribs) have been omitted for the sake of clearness ; the last costicartilage has been shortened so as to show its actual condition ; the principal bones have been named, and the coste and vertebre have been numbered ; the shading is likewise altered somewhat. § 206. Like the body as a whole, the skeleton comprises a somatic (‘‘axial’’) portion including the bones of the head, neck, thorax, abdomen, pelvis and tail, and a membral (‘‘appendicular’’) portion, including the bones of the arms and legs. ANATOMICAL TECHNOLOGY. 88 waendiong parsers Burpwtinsca muy R | THE SKULL AND VERTEBRA. 89 The membral bones have been shown from the dorsal aspect in the normal position of the parts in Fig. 6, but in Fig. 30 the animal is represented from the left side, in one of its natural attitudes while standing or walking. In this attitude the limbs are directed ventrad instead of laterad, and are thus nearly parallel to each other; while their segments and the general divisions of the somatic skeleton, the head, neck, trunk and tail, form angles with each other, imparting to the whole skeleton a graceful and spirited appearance. § 207. Skull—(Fig. 56-62).—The cephalic division of the so- matic skeleton is the skull, consisting of the eranium or brain- case, and the face, to which appertains the mandible or lower jaw. The transverse ridge at the junction of the dorsal and caudal as- pects of the skull is the Crista lamdoidalis (Fig. 56, Cst. lmd.); the darkly shaded area between the cranium and the face repre- sents the left orbiz, and the longitudinal irregular bar just ventrad of it is the zygoma, or arcus zygomaticus (Fig. 56). The Os hyoides will be described in § 224. § 208. Vertebre—(Fig. 51-55).—Caudad from the skull extends a series of bony segments—the Vertebre—constituting the Colwmna vertebralis or spine or spinal column. As seen from the side, the Columna presents two curvatures in opposite directions, like an elongated letter s. For convenience and more or less naturally, the vertebree may be grouped in five divisions, cervical, thoracic, twmbar, pelvic or sacral and caudal. The numbers following the names of these groups upon Fig. 30 are those which are most commonly observed, but variations sometimes occur, as will be mentioned in the descrip- tion of the Columna vertebralis. The vertebree of each group have certain features in common, and also individual peculiarities by which, excepting most of the caudales, they may be distinguished when completely isolated. On the entire skeleton, the groups are most readily recognized on account of the connections of three of them with other parts, as follows :— The thirteen thoracic vertebree are costiferous, that is, connected with the ribs; the cervical series begins at the skull, and the three sacral vertebrae are united so as to form a single bone—the sa- crum—to which is attached the Os innominatum on either side. The lumbar vertebree intervene between the thoracic and the sa- 90 ANATOMICAL TECHNOLOGY. crum, while the caudal vertebrae extend caudad of the last-named bone. The first and second cervical vertebree (Fig. 52), are also called, respectively, atlas and axis. The former is expanded laterally in wide transverse processes. The latter presents a Spina neuralis, which is both long and high. The seventh cervical spine and the first five thoracic are hidden in Fig. 30. The first nine or ten thoracic spines are directed more or less decidedly caudad, but the last two or three, like the lum- bar, are directed cephalad, while the tenth or eleventh has an inter- mediate direction. The various processes become less and less dis- tinct among the caudal vertebre, and the caudal members of the series are little more than subcylindrical segments of bone. Unlike most anatomists, Straus-Durckheim includes (B, I., 480, Pl. xi., B, C), the eleventh, twelfth and thirteenth thoracic vertebre with the lumbar series. § 209. Coste—(Fig. 50).—Each costa (rib) is seen to be con- nected by its dorsal end with the thoracic region of the Columna vertebralis, and at its ventral with a costicartilago. Part of the first costicartilage appears in Fig. 30 just cephalad of the left shoulder joint, but the second rib and its cartilage are wholly concealed by the scapula and humerus. § 210. Sternum—(Fig. 49).—The sternwm, or breast-bone, con- sists of a series of eight or nine mesal segments called sternebre. The caudal piece is the xiphisternum or Ctl. ensiformis, and is partly cartilaginous. The cephalic segment is the presternum or manubrium, and the intervening six or seven sternebre constitute the mesosternum. § 211. Scapula— shoulder blade—(Fig. 48-45).—The ectal as- pect of this bone, as shown in Fig. 30 and 44, presents a ridge, the mesoscapula, which has three prominences—acromion, meta- cromion, and tuberositas. § 212. Clavicula—The clavicle or collar bone—(Fig. 48)—In the cat these bones are small and imbedded in the muscles, with- out direct attachment to other bones. They are shown in Fig. 30, one on each side, between the shoulder joints. A. In the cat the scapula appears as a partof the arm. In man, however, and in many other vertebrates, the clavicles are larger and articulated with the scapule and the sternum. In most reptiles and birds, and in two Mammals (Echidna and Ornithorhynchus) the scapula and the sternum are connected by a stout osseous bar—the coracofd—which is represented in the cat as in man by merely a process—the Pre. corucoideus ; Fig. 48, 45. ANTAGONISM OF THE MEMBRAL SEGMENTS. 91 B. The two scapule with the clavicles and the coracoid bones are commonly regarded as constituting a sort of belt—the scapular arch or shoulder girdle. § 213. Pelvis—Pelvic Girdle—(Fig. 51).—This limb girdle is complete in the cat. Each lateral piece—Os innominatwm—is at- tached to the sacrum by its dorsal end, and ventrad joins its platetrope (fellow of the opposite side) at the symphysis pubis. The rounded vertebral end of each os innominatum is the Crista alii, and the caudal end is the dschiatic tuberosity. § 214. Shoulder and Hip Joints.—These are the proximal arthra of the arm and the leg respectively, forming their points of attach- ment with the shoulder girdle and the pelvis. Both are ball-and- socket joints, but the former is the more free, and the position of the entire joint may be changed on account of the suspension of the scapula in the muscles. § 215. Elbow and Knee.—These are both hinge joints, the lat- ter being less encompassed by bone, and hence somewhat the freer of the two. At the knee the femur articulates with the tibia only, while the elbow is between the humerus and both the ulna and radius. § 216. Wrist and Ankle.—The latter is a true hinge joint, but the former combines features of the hinge and the ball-and-socket varieties. § 217. The Bones of the Limbs.—All of these have been named in the Introduction in connection with the description of Fig. 6 ($$ 82-85), and some will be described hereafter with more detail. Reference will be made here only to certain general features of the larger bones, and to the attitudes of the entire limbs. Antagonism of the Membral Segments.—It will be noted that, excepting the distal segments, the corresponding segments of the limbs point in opposite directions, and that the same antagonism exists between the principal elements of the scapular arch and the pelvic girdle. As a necessary concomitant, any two successive segments, excepting in the case of the manus and antebrachium, point in opposite directions. From this relation of the segments there are two results: First, that the weight of the body rests upon columns which are not only near its opposite ends, but also tend to counteract each other for the most part, so that stability is more easily maintained. Neverthe- less, by exception, the distal segments coincide in direction, so that both limbs may strike the ground in one direction, and thus propel 92 ANATOMICAL TECHNOLOGY. the body in the other. Second, these limbs are more elastic than if the several segments were in the same line, and the muscles act upon the bones to better mechanical advantage. § 218. By some writers (Wyman, 75, 253; Coues, 7, 15), and formerly by the senior author (5, 45), this opposed or symmetrical or autitropée relation of the scapula and ilium, and of the propodial and epipodial bones of the arm and leg las been regarded as evidence in favor of a general symmetrical homology between the two limbs. The senior author, however, has admitted (10, 15) that this antagonistic relation is secondary and telical rather than primary and morphical, and has fully assented to the view that in their normal position both pairs of limbs extend laterad from the trunk, and their flexures are in the dorso-ventral rather than in the cephalo-caudal direction. § 219. To replace the limbs in their normal and primitive posi- tion (see § 45), it is necessary to rotate the elbow cephalad and the knee caudad, and then—if the commonly accepted view be correct— to lateriduct both limbs until they are at right angles with the meson, as in Fig. 6. This rotation will leave the convexities of the elbow and the knee facing dorsad (as in Fig. 7), and that of the ankle, with the plantar aspect of the pes, facing ventrad. In the arm, however, the corres- ponding aspect of the manus—the palm—will be left facing dorsad, and the ulna and radius will be crossed instead of parallel like the corresponding tibia and fibula. But if the manus be supinated, the ulna and radius will be parallel, and the palm will face ventrad like the sole. The restoration just described is assumed to have taken place in the following brief account of some of the bones and their promi- nences :— § 220. The proximal end of the humerus presents an elevation, the trochiter or Tuberositas major (Fig. 45, 46), which is cephalic in the normal position of the parts, but lateral in their natural atti- tude. At the distal end of the same bone (Fig. 46) are two eleva- tions, the epicondylus and epitrochlea, commonly called external and internal condyles. In the natural attitude, as seen in Fig. 30, the epicondyle shows on the left arm, and the epitrochlea on the right. The wna projects dorsad and proximad of the elbow as a thick process, the olecranon. Just distad of the joint, on the ventral side of the bone, is an elevation—the Processus coronoideus—for the attachment of the I. brachialis. The proximal end of the radius is the capitel/wm, while the distal end of each antebrachial bone presents a short Pre. styloideus. THE POSITIONS OF THE ARTHRA. 93 The individual carpalia are not easily distinguished, but the O. pisiforme is seen on the right side ; see Fig. 47. § 221. At the proximal end of the femur is a marked process, the trochanter, which is naturally visible in the lateral view of the bone, but normally has a caudal position. At the distal end of the same bone are the cephalic and caudal (‘‘inner and outer’’) con- dyles. At the convexity of the knee, and thus normally dorsad of the joint, is the patella, which answers in some respects to the olecranon, but is really only a very large O. sesamoideumn. The ¢ibia is seen to be both larger and longer than the fibula, which indeed does not enter into the composition of the knee. The malleoli, cephalic and caudal (internal and external), are slight elevations of the distal ends of the tibia and fibula respectively. Of the tarsalia, the prominent calcaneum is easily recognized. § 222. In ordinary locomotion neither the palm nor the sole are in contact with the ground excepting at the junction of the metacar- pal and metatarsal regions with the digits and dactyls; the body is supported upon the ball of the foot and the dactyls and upon the corresponding parts of the manus, aud the cat is thus a typical digitigrade. We can imitate its condition so far as concerns the elevation of the heel and the support of the body mainly upon the ball of the foot; but the human digits and dactyls can- not be brought into the state of the cat’s, where the proximal phalanges are flexed dorsad, the intermediate ventrad, and the distal ones again dorsad so as to keep the sharp claw points off the ground. § 223. The Positions of the Arthra.—lIt will be noted that the arthra of the arm are ventrad of the corresponding arthra of the leg, although the manus and pes are upon the same plane, and the vertebral ends of the scapula and ilium are at nearly the same level. Since there is little difference in either length or inclination between the humerus and femur, and the radius and tibia, this difference in the levels of the arthra must be associated with the greater length of the pes as compared with the manus, and with both the length and more nearly vertical direction of the scapula as com- pared with the ilium. Notwithstanding the popular designation of the wrist of a horse as its “knee,” it should be kept in mind that the true knee of the mammalian quadruped is a joint 94 ANATOMICAL TECHNOLOGY. of the leg, and, like its counterpart the elbow, is but slightly removed from the level of the ventral border of the trunk. The ankle of the quadruped is often called hough or hock, § 224. Os Hyoides and Larynx—(Fig. 3(0).—Dependent from the caudal region of the basis cranii is an inverted segmented bony and cartilaginous arch—the Os hyoides. Connected with the summit or ventral end of this arch is the larynz, a cartilagi- nous case forming the principal organ of the voice. (In Fig. 30 the larynx is placed too nearly in contact with the fifth Vertebra cer- vicalis). The keystone of the arch appears in Fig. 30 only by its sinistral end, shown as a small subquadrate area close to the angle formed by the junction of the ventral outlines of the head and the neck. The lateral bar extending from this point caudad and slightly ventrad is one of a pair of pieces called thyro-hyals, which are additions to the arch itself, and are most directly connected with the larynx. Each lateral half or pier of the arch consists of four segments, as follows :— Next to the basihyal is the cerato-hyal. Then comes the epihyal, and then the stylo-hyal. In the figure the dotted line from the words os hyoides is drawn to the arthron between the cerato-hyal and epihyal. The three pieces mentioned are bony ; the fourth piece, which appears in the figure along the side of the bulla, is cartilaginous, and has been called Cél. stylo-hyoidea. It is attached at the bottom of a deep pit just laterad of the bulla; (see Fig. 57, F's. tyh.). The sequence of the osseous segments may be connected with the alphabetical order of the initials of their names, B, C, #, and 8. A. For fuller accounts of the Os hyotdes, and for the origin of the names of the seg- ments, consult Owen, A, II.,506; Flower, A, 123. Straus-Durckheim’s account (A, I, 450- 453) is not very satisfactory. The figures of Mivart (B, 78) are good, but he ascribes to the cat a small osseous segment—the tympano-hyal—which exists in the dog (Flower, A, 123), but which we have failed to find in even old cats, and which is not mentioned by Straus-Durckheim. B. In man the thyro-hyals are disproportionately large, and are called the greater cornua, while the cerato-hyals are called lesser cornua. Quain, A, I, 455; Gray, A, 206; Parker and Bettany, A, 305. The following parts of the larynx may be recognized in the figure :— The largest and ventrally placed piece, and that which is reached ANATOMICAL LANDMARKS. 95. by the dotted line, is the CZ. thyroidea. In man it forms the mesal projection known as ‘‘ Adam’s apple.” Just ventrad of it in the figure, but caudad in the normal position of the parts, is the ring shaped Cél. cricoidea. Each thyro-hyal segment of the Os hyoides is directly connected with the larynx by a small CZ. arytenoidea, one of which is indistinctly shown in the figure at the dorsal (really cephalic) end of the prolongation of the Cél. cricoidea. The epi- glottis is seen projecting just dorsad of the thyro-hyals. ANATOMICAL LANDMARKS. ’ § 225. During dissection and experimentation it is often de- sirable to determine the lines and limits of incisions, or to ascertain the location and outline of parts which are obscured by the skin or other soft parts. The elevations and depressions which may serve as guides are called anatomical landmarks. The landmarks here described should be carefully studied, first upon the prepared skeleton by the aid of figures and descriptions, and then upon the entire cat by the aid of preparations of the soft parts, and frozen sections and dissections. Most of the landmarks are more easily recognized upon the living or freshly killed animal, but they should be sought also during the continuance of rigor mortis, and upon specimens hardened by alcohol. Finally, their recognition should be practised also with the eyes closed. Whoever intenas to perform experiments should become sufficiently intimate with some cat to be permitted to manipulate all the accessible parts. The late Prof. Jeffries Wyman once told the senior author that in Paris he lived in the same house with Straus- Durckheim ; and that the indefatigable felitomist would sometimes sit by the hour holding a cat, and passing his fingers from point to point over the muscular elevations, the joints and other bony prominences with which his mind was occupied at that time. The landmarks form three groups, mesal somatic, lateral so- matic, and membral. § 226. Mesal Somatic Landmarks — Crista lambdoidalis— (Fig. 56).—Prominent as is this crest upon the prepared skull, it is by no means easy to find upon the entire animal. The cervical muscles just caudad of the occiput are very firm and compact, so that the change of substance is not very marked to the touch. The crista, however, is nearly in a line with the most caudal con- vexity of the ears, and may be more distinctly felt during alternate ventriduction and dorsiduction of the head. § 227. Spina Neuralis Axvialis—The axial spine—(Fig. 30).—The somewhat sharp caudal projection of this spine may be felt at the dorsimeson between the cervical muscles 3-4 cm. from the Crista lambdoidalis, and not far from the scapule. 96 ANATOMICAL TECHNOLOGY. Spina Neuralis Thoracica Prima—tThe first thoracic spinous process.—This is about half as long again as that of the seventh cervical vertebra, and larger at the tip than the succeeding thoracic spines. In the living animal, it is at the bottom of the interscapular depression, but one or both of the scapula may be ventriducted so as to leave it more prominent. In man, it is the seventh cervical spine which is longer than the rest, whence the name Vertebru prominens sometimes applied to the vertebra. Sp. Nrl. Thr. 13—(Fig. 30).—This is a little cephalad of the vertebral ends of the last ribs, and may sometimes be distinguished from the other thoracic spines by its greater cephalo-caudal extent, wherein it resembles the lumbar series. The tenth or eleventh spine is usually quite short, so as to leave a slight hiatus about 2 cm. cephalad of the thirteenth. In counting the spines beginning with the first, the thirteenth will usually appear to be the twelfth on account of the short one just mentioned. If the lumbar series be counted, attention must be paid to the point next mentioned. Spina Lumbalis 7—The last lumbar spine.—This projects just cephalad of a line between the Criste iliorum, while the first sacral spine projects between the Cristee, so as to be hidden by them in the figure of the entire skeleton (Fig. 30). § 228. Pubes—(Fig. 51).—The cephalic border of the pubic bone is easily felt both at and laterad of the ventrimeson. Epigastrium and Xiphisternum—(Fig. 72).—The epigastrium is a subtriangular area at about the junction of the cephalic and middle third of the trunk. Its latero-cephalic borders are formed by the ninth and tenth costicartilagines. The xiphisternum (Fig. 30, 49, '72,) may be felt on the meson ina lean cat, but it is some- times obscured by fat. Presternum—(Fig. 30, 49).—This is easily distinguished either on passing the finger cephalad along the sternum to the neck, or caudad along the neck until it reaches the somewhat sharply pro- jecting point. Larynx — (Fig. 30).—This forms a compressible ventrimesal prominence about midway between the preesternum and the chin when the head is dorsiducted so as to bring the ventral surface of the neck and head into the same plane. Lateral Somatic Landmarks.—These, of course, are in pairs, but they will be spoken of in the singular number, MEMBRAL LANDMARKS. 97 § 229. Zygoma—The Arcus zygomaticus—(Fig. 30, 56).—Both the dorsal and ventral borders of this may usually be felt distinctly, although in old males it is more or less obscured by the thickness of the skin and connective tissue upon the cheeks. The dorsal border is nearly in line with the lateral angle of the eye. Diapophysis atlantalis—Transverse process of the atlas verte- bra—(Fig. 30, 52).—This may be felt as a ridge just caudad of the base of the ear. The caudal angle is more distinct, and the soft parts on its ventral side are less prominent and firm than those upon the dorsal. Scapula—(Fig. 30, 44).—The middle of the convex vertebral margin of the scapula projects dorsad of the intervening cervical neural spines, so as to give rise to the Depressio interscapularis which is so marked while the living cat is on its feet. Upon a lean animal, the following scapular prominences may be easily deter- mined: mesoscapula, with its tuberosity (Fig. 44); gleno-vertebral angle (Fig. 48); (the coraco-vertebral angle is so heavily overlaid with muscle as to be less easily felt); acromion (Fig. 44, 45); metacromion. § 230. Costa 13—Last rib.—The abdominal parietes just caudad of the last rib are easily indented by the finger almost to the apex of the triangular area which intervenes between it and the lateral border of the vertebral muscles (Fig. 30). Crista ilii.i—When the finger is carried along the border of the vertebral muscles at about the same distance from the meson as the apex of the angle between them and the last rib, the Crista @it is felt as a rounded ridge nearly dorsad of the knee (Fig. 51). Tuberositas ischii—Ischiatic tuberosity.—This is felt as a blunt prominence ventro-laterad of the anus. Clavicula—The clavicle or collar bone—(Fig. 30, 48, 67, 72).—In young or lean animals this may be felt by pinching up the skin and subjacent muscles between the shoulder and the preesternum. Membral Landmarks.—These, likewise, are in pairs, but are spoken of in the singular number. § 231. Arthra.—After what has been said in the general descrip- tion of the skeleton (§§ 214-223), there will be no difficulty in ascer- taining the position of any of the membral arthra. Most of the bony prominences also may be recognized readily from their rela- tions to the arthra. Trochiter—(Fig. 30, 46)—The greater tuberosity of the humerus.— 7 98 ANATOMICAL TECHNOLOGY. This forms a marked projection at the convexity of the shoulder, a little ventro-cephalad of the acromion. Olecranon, Epicondylus and Epitrochlea—(Fig. 30, 46).—These prominences about the elbow joint are recognized without difficulty even in fat animals if the parts are manipulated between the thumb and fingers. M. biceps—(Fig. 74, 75).—The fusiform body of this muscle may be felt on the ventral aspect of the antebrachium by rolling the soft parts gently between the fingers upon the humerus. It is less dis- tinct than in man, on account of the more distal extension of the insertion lines of the pectoralis group of muscles. § 232. Capitellum radii—Head of the radius.—By alternately pronating and supinating the manus while a finger is pressed upon the elbow a little ventro-distad of the epicondylus, the capitellum may be felt during its rotation. Processus styloides ulne et radii—The styloid processes of the ulna and radius.—These are to be felt at the caudal and cephalic sides of the wrist joint. Os pisiforme—(Fig. 30)—This forms a marked and somewhat movable projection just proximad of the wrist, and on the caudo- ventral border of the antebrachium. Just distad of it is a promi- nent callosity—the hypothenar eminence (Fig. 105). § 238. Trochanter—Trochanter major femoris—(Fig. 30).—This projects considerably from the hip, a little ventrad of a line between the Crista ilii and the Tuberositas ischii, and a little nearer the latter. Its movement is distinct when the leg is moved. Patella—The knee pan.—When the crus is extended so as to relax the muscles connected with the patella, this bone is easily moved from side to side. Calcaneum.—This forms the marked projection on the ventral aspect of the leg just proximad of the ankle ; it is sometimes called the hock. Malleoli.—These processes of the distal ends of the tibia and fibula are readily distinguished at the cephalic and caudal sides of the ankle. ABDOMINAL TRANSECTION. § 234. Since most of the dissections herein described involve only the thorax, neck, head and arms, it is usually more convenient and economical to divide the body into caudal and cephalic parts. ABDOMINAL TRANSECTION. 99 The former may then be thrown away, and the latter preserved, or dissected while fresh. The kidneys are important visceral land- marks, and are easily preserved, hence they may be retained with the cephalic part. Abdominal transection may be performed alone, but it is more conveniently done when another person holds the cat in the desired positions. The assistant, also, may read the directions to the operator. § 235. Instruments and Materials. — Arthrotome ;_ tracer ; medium scalpel; coarse curved scissors; hair scissors; block; twine, about half a meter; skeleton; wide mouthed jar (about 6x12, 15 or 18 in.); alcohol, 52-67 per cent., to half fill the jar; coarse syringe ; large tray. § 236. Parts Involved—tThe following parts are more or less directly involved in Abdominal Transection. From the figures and sections referred to, enough should be learned to enable the operator to recognize them during the operation :— Aorta.—Fig. 101. Columna Vertebralis.—The spinal column. Coste—Ribs.—Fig. 30, 50, 73. Costicartilagines—The costal cartilages.—Fig. 30, 50. Crista tlii—The crest of the ileam.—Fig. 30, 51. Diaphragma—tThe diaphragm.—Fig. 90, 101. Epigastrium—tThe ‘pit of the stomach.’’—Fig. 30, 72. Lribro-cartilago intervertebralis—The (sixth lumbar) interverte- bral disk of fibro-cartilage.—Fig. 51. Hepar—The liver.—Fig. 77. Intestinum Tenue—The small intestine.—Fig. 77. Ligamentum Suspensorium Hepatis—The suspensory liga- ment of the liver. Mesenterium.—Fig. 78. @sophagus—The gullet.—Fig. 107. Parietes Abdominales—The abdominal parietes, the muscular and membranous lateral and ventral walls of the abdomen.—Fig. 77, 101. Pelvis—The pelvic girdle —Fig. 30, 51. Posteava—Vena cava inferior s. ascendens.—Fig. 101. Rectum.—Fig. 77. enes—The kidneys.—Fig. 79, 101. Stomachus—The stomach.—Fig. 78, 81. 100 ANATOMICAL TECHNOLOGY. Thorax—The chest.—Fig. 30, 77. Vertebre lumbales—The lumbar vertebree, with their diapo- physes and zygapophyes.—Fig. 30, 51, 55. Xiphisternum—The ensiform cartilage of the sternum.—Fig. 30, 49. § 237. Operation.—Place the cat dorsicumbent, the head to the left. Pinch up the right abdominal parietes about midway be- tween the crista ilii and the last rib. With the arthrotome, transfix the fold so pinched up, and cut ento-ectad to the surface. If only the skin is divided at the first attempt, pinch up the muscles and repeat the transfixion, but be careful not to include any of the intestines within the fold. Into the incision so made, insert the left index and medius, the hand being supinated, and lift the parietes away from the viscera. Introduce the scalpel, with the edge directed ectad, and divide the parietes on each side until the thicker vertebral muscles are reached a few centimeters from the dorsimeson. The dorsal ends of this transverse incision should be just caudad of the kidneys. About 2 cm. sinistrad of the ventrimeson, divide the parietes longitudinally to the pelvis and the epigastriwm, making sure not to cut the ziphisternum or costicartilages. Turn aside the four rectangular flaps so formed, and draw the intestines caudad. Introduce the pronated left hand between the liver and the parietes until the fingers are met by the diaphragm. Partly flex the fingers, and push them somewhat dorsad; then draw the diver and stomach caudad ; this will expose the Tendo centralis of the diaphragm, which should be punctured with the tracer. The admission of air into the thorax will permit the farther caudiduction of the liver and stomach. § 238. If the cephalic part is to be preserved, ligate the rectum and then the stomach and liver, and inject 84-95 per cent. alcohol into the aorta, as directed in § 285. After two hours a plaster injection may be made if desired. Then proceed as in § 239. If the parts are to be dissected fresh, or if the muscles are to be exposed and the thorax opened so soon as to render the alcohol injection unnecessary, proceed as in § 239. § 239. Insert the curved scissors, keeping the convexity toward the diaphragm, and divide the Ligamentum suspensorium of the liver, the postcava and the abdominal esophagus; while so doing, the viscera should be drawn ventrad as well as caudad, so as to put the parts named upon the stretch. PRESERVATION AND LABELING. 101 When the liver and stomach are free, draw them and the intes- tines caudad, dividing the mesal peritoneal attachments (mesente- rium) to a point 5-6 cm. caudad of the kidneys, but do not remove the latter. Compress the rectwm between the fingers so as to force its con- tents in both directions ; ligate it in two places about 2 cm. apart, and cut between the ligatures (Fig. 41). The viscera thus freed may be thrown away unless wanted for some purpose. § 240. Place the block under the cat opposite the kidneys. Press upon the thick muscles just caudad of the kidneys, and about 2 em. laterad of the meson. The sizth lumbar diapophyses (see Fig. 30) will be felt. With the arthrotome, divide all the soft parts on the ventral aspect of the dwmbar vertebre between the tips of the sixth diapophyses, and scrape them caudad for about2cm. This will expose a transverse whitish swelling, the ¢ntervertebral fibro-carti- . lage between the sixth and seventh lumbar vertebree. If the kidneys are not to be kept, or if it is desirable to make the whole preparation shorter, the columna vertebralis may be divided between the second and third or third and fourth lumbar vertebre. Push the arthrotome into this fibro-cartilage, and cut dextrad and sinistrad as far as possible. Then cut latero-cephalad on each side to the tip of the diapophysis; then directly laterad so as to divide the thick vertebral muscles. Grasp the cephalic part of the cat just cephalad of the incision, and lift it from the tray. If this does not disjoint the zygapophyses, bend the caudal part downward until the ligaments give way, and the zygapophyses are separated. Cut the remaining soft parts and the skin, and thus complete the transection. The caudal part may be thrown away. Knead the thorax so as to expel the blood, place the cephalic part—which may be spoken of now as the cat—upon a clean dry tray, or upon paper laid in a tray, and remove the hair, as directed in Chap. VI.; note the precautions as to the disposal of hair, § 197. § 241. Preservation.—Tie the twine firmly about the last lum- bar vertebra (which is the sixth if the directions have been fol- lowed), and make a loop through which may be passed a second piece of twine already attached to the ring of the jar cover, or, better, an S-hook connected with the cover by a string of suitable length. To the vertebra should also be tied a tag bearing the brief record of the sex of the cat, its age or apparent period of growth, 102 ANATOMICAL TECHNOLOGY. its color, the date of killing, and the name or initials of the dis- sector ; a similar tag should be attached to the jar. The cat may then be suspended in the jar head downward; all parts should be immersed in the alcohol. If any parts press closely against the sides, some cotton or ‘‘excelsior”? should be interposed. If the cat can be left in the alcohol for at least a week, the parts are more completely and uniformly hardened. § 242. Thoracic Transection.— This is sometimes desirable when only the abdominal and pelvic regions are to be examined or preserved. The primary incision should be transverse, about 2 cm. cephalad of the epigastrium. The mesosternum may be divided with the nippers, and the incision then carried on either side in the 7th inter- costal space. The thoracic viscera are readily separated from the diaphragm, the cesophagus, aorta, and postcava may be cut 1-2 cm. from the diaphragm, and the dislocation of the columna verte-. bralis effected between the seventh and eighth thoracic vertebre. If the abdominal viscera are to be preserved, strong alcohol should be injected into the aorta, and into the abdomen by a slit just large enough to admit the canula; the contents of the stomach and rectum should be, if possible, washed out with a stream of water, aided by kneading; alcohol should then be injected into both cavities, the cesophagus tied, and the rectum plugged with cotton. The abdominal viscera are easily displaced, and it is well to let the caudal region of the body, with or without the legs, rest dorsicumbent in alcohol for several days, the jar being securely closed, and placed on its side ina tray. The alcohol should be re- newed at the end of a week. § 243. Removal of the Tail.—In some cases it may be desirable to remove the tail. Girdle it with the arthrotome near the base, and divide it with the nippers and bone scissors. With a young animal, the bone scissors may be used without the nippers. With a freshly killed animal, when bleeding is undesirable, a twine ligature may be tied firmly just cephalad of the point of intended removal. If only the muscles, vessels, and nerves are to be studied, the claw points may be removed with nippers. CHAPTER III. PREPARATION OF BONES—PERMANENT PREPARATION OF SOFT PARTS—THE USE OF ALCOHOL, ETC.—JARS, ETC.—FROZEN SECTIONS AND DISSECTIONS—INFLATED PREPARATIONS—MEASUREMENT OF VOLUME AND CAPACITY. PREPARATION OF BONES. SPECIAL INSTRUMENTS AND MATERIAL :—Arseniate of Soda—Beans or Peas—Benzine — Bone Drill — Cement — Ether — Glycerin — Labels (§ 162) — Liquid Soap — Macerating Dishes — Nail or Tooth Brushes — Salt Solution — Syringe — Turpentine Oil — Wicker. sheimer’s Liquid. _§ 244. There are four principal methods of preparing bones for scientific purposes :— (1) Cutting and scraping the soft parts from alcoholic specimens. (2) Allowing Ants or Dermestes to remove the soft parts of fresh specimens. (3) Maceration (putrefactive) in water. (4) Boiling with liquid soap. General Directions.—A. If one can choose his specimen, a young adult should be selected. In too young animals the epiphy- ses are apt to separate easily from the diaphyses, and the symphy- ses open too easily. On the other hand, old animals sometimes have exostoses, or abnormal growths on their bones, and the sym- physes and sutures are liable to be entirely obliterated. B. If possible, have at hand for reference a perfect skeleton of the part to be prepared, so that the exact position of delicate bones and processes may be seen, and hence not be lost or broken through inadvertence. C. Whatever method is employed, it is better to divide the animal into several parts by cutting some of the principal arthra, as the humero-scapular, the femoro-innominate, the occipito-atlan- . tal, and the lumbo-thoracic. D. Labeling.—The whole animal should bear a label giving the name, date, sex, and, if possible, the age. Hach separated part 104 ANATOMICAL TECHNOLOGY. should bear a label giving the above general data, and also the name of the part. This is imperatively necessary with the verte- bree, the ribs, and the phalanges; hence each must be carefully labeled as it is separated from the rest of the body. E. If the methods of maceration or heating with liquid soap are employed, parts like the -pelvis and scapule, and limb bones, exclusive of the manus and pes, which cannot be mistaken, may be put together and labeled as for the whole animal. Parts that might be difficult to distinguish should be kept in separate dishes, and each properly labeled. The vertebree might be divided into the four sets—cervical, thoracic, lumbar, and sacral; each set should then be connected by attaching a Manilla hemp string to a wire and passing it through the neural canal and tying the ends. The order of the bones cannot then be changed as they separate in the macer- ating process. The caudal vertebree that have no neural canal must be num- bered or put in separate dishes or vials and properly labeled. The ribs of one side at least should be removed one by one, and tied in order on a string, or put into separate dishes. Never put bones of different animals in the same dish, unless they differ so greatly in size or conformation that confusion would be impossible. F. The humerus, femur, tibia, and radius should be drilled at or near their ends, so that the oily matter in the medullary canal may be removed. The tibia and radius may be drilled in the artic- ular surfaces, care being taken to reach the center of the thickness ofeach bone. The distal end of the femur may be drilled, but the proximal hole should be made on the ventral side, between the tro- chanter and the articular head. With the humerus, the proximal hole may be made in the articular surface, about midway between the base of the trochiter and. the trochin, but cephalad of the slight extension of the Canalis bicipitalis. The distal hole may be drilled half way through the diaphysis, from a point on the cephalic aspect, at the junction of the third and fourth quarters. After the holes are made, the medullary matter may be broken up with a wire, and most of it expelled by syringing, first with warm water and afterward with liquid soap, or spirits of turpentine, or ether. The syringing should be repeated at the close of what- ever process is adopted for removing the flesh. With most larger animals, and with some smaller ones, it may be desirable to drill the wna and fibula also. MACERATION IN WATER. 105 § 245. Removing Soft Parts from Alcoholic Specimens.— Animals that have been preserved in alcohol may have their bones cleaned by simply cutting and scraping away the soft parts. It will be necessary to take great care, however, or the delicate pro- cesses, especially of the skull, will be broken in getting off the tough connective tissue. After the bones are cleaned as well as possible, simply allow them to dry, or finish the cleaning as directed hereafter (§ 249). § 246. Allowing Ants or Dermestes to remove the Soft Parts of Fresh Specimens.—The skin and most of the flesh should be dissected away, and the partially cleaned bones left in a damp room. Dermestes will find them, and the larve of the beetles will remove the soft parts. If the aid of ants is to be sought, the bones prepared as just directed should be sprinkled with sugar or smeared with molasses or honey. Then they should be placed in a box pierced with small holes. The box should be put by an ant’s nest, and some sugar sprinkled around the holes leading into it. The ants will clean the bones more satisfactorily than the Dermestes. It usually takes about a week for them to clean a cat’s arm. § 247. Maceration in Water.—Employ stone-ware, porcelain or glass dishes, if possible, to avoid discoloration of the bones. The bones are freed from skin and most of the soft parts, separated, placed in separate dishes as directed above, and covered completely with clean soft water. The dishes should then be placed in a room where the temperature does not fall below 18-20 C. Ifthe room is still warmer, the maceration will proceed all the more rapidly. The water should be changed on the third day, and again on the tenth, to avoid discoloration. It requires from a fortnight to two months for complete macera- tion. The bones of very large animals may require even a longer time. If possible, maceration should be done in a separate building, and during warm weather. If done during cold weather, the fire should not be allowed to go out, or adipocere, a waxy substance, may form, which is difficult to remove. If the maceration is done in a room or closet, there should be a special ventilating flue ($ 196). During maceration the bones should be occasionally examined. When the soft parts separate readily, the water covering them should be carefully poured off, and a gentle stream of fresh water 106 ANATOMICAL TECHNOLOGY. allowed to play upon them. Use a nail or tooth brush to remove the flesh, and if it is necessary employ the scissors, forceps, and a dull but smooth-edged knife to clean some parts; the nippers aid in tearing off ligaments and tendons. After all the soft parts are removed, rinse the bones well with clean water, and place them on white paper in a dry room. Do not fail to accompany each bone by its proper label (§ 244 D). The vertebra, ribs, ete., should be kept on astring after cleaning, or when dry they may be numbered. The skeleton of each animal should be kept ina separate box and properly labeled. § 248. Liquid Soap Process.—The cleaning is done in this pro- cess by heating the bones in a dilution of the following mixture: Rain (or distilled) water, 2000 cc. ; strong ammonia, 150 cc. ; nitrate of potash (saltpetre), 12 grams ; hard soap, 75 grams. Prepare the bones by removing the skin and most of the soft parts, as directed for macerating (§ 247). Place the bone, or—if several are to be prepared from the same animal—those that cannot be mistaken for one another, in a vessel containing water, 4 parts, and liquid soap, 1 part. Prepare enough of this mixture to completely immerse the bones. Boil in this forty minutes; then pour off the liquid and add a similar amount prepared in the same way. Boil again for half an hour; and usually the muscles may be removed by the hands, a smooth stick, or a scalpel handle. As it would take too long for the bones to cool spontaneously before working upon them, they may be placed directly in cold water. After removing all the muscles that come off readily, replace the bones in the dish and continue the boiling until the soft parts may be readily removed with a nail brush. When removing the soft parts, it is necessary to be careful not to lose smal] bones. After all the soft parts are removed, it is usually best to boil the bones for half an hour in a mixture of equal parts of the liquid soap and water to remove the last remnants of grease. Finally rinse the bones well with clean water and lay them upon white paper to dry. This is by far the best method of preparing bones: (1) The liquid soap saponifies the fat and aids in softening connective tissue. (2) The bones come out white and free from grease. (8) It requires PREPARATION OF SKULLS. 107 but a very short time to prepare a skeleton or a part of a skeleton. (4) It is especially adapted for skulls, as the teeth are much less liable to fall out, and the gelatinized dental periosteum serves as a cement. (5) There is no danger of blood poisoning (septicemia) if fresh, healthy animals are used. There is no danger in any case after the bones have been well boiled. § 249. Bones are not satisfactorily cleaned by ants or Dermestes. The cleaning may be very satisfactorily completed, however, by boiling in the mixture of liquid soap (§ 248). The final cleaning of alcoholic specimens is best done in the same way. § 250. Preparation of Skulls—A. By Maceration.—Separate the skull, remove the skin, the eyes and the tongue. Then separate the mandible, but let the os hyoides remain. With a tracer or a piece of wire, inserted through the FYoramen magnum (Fig. 57), break up the brain, taking care, however, not to injure the project- ing bony ¢entoriwm (Fig. 59). After the brain is broken up it should be washed out with a syringe. Place the skull and mandible in the macerating dish so that the teeth shall be uppermost; then, if the water is changed carefully, the teeth are less apt to fall out and be lost. The cleaning should be done as described above (§ 247), except that greater care is usually necessary. B. By the Liquid Soap Process.—The skull should be prepared as described for maceration, except that the mandible need not be separated. Proceed as directed above (§ 248). Skulls can be much more quickly and safely prepared by the liquid soap process than by any other. § 251. Cements for Bones and Teeth.—The pelvis and man- dible often separate at their symphyses, and the teeth may become loose and be in danger of falling out. This latter is especially liable to occur with macerated skulls. To unite bones, one should use :— A. Liquid gelatin (see Formula, § 1446). Attach the bones firmly by a rubber band or string while the gelatin is drying. The method is the same as for gluing wood. Teeth may be fastened in their sockets by the same substance, only it is unnecessary to bind them in while the gelatin is drying. The skull should rest on its dorsal side, and the mandible on its ventral side, so that the teeth may remain in place during the drying. 108 ANATOMICAL TECHNOLOGY. B. An excellent cement, for teeth especially, is the following :-— Silicate of soda or potassa (liquid glass) mixed to a paste with powdered chalk. This hardens quickly, therefore it must be used soon after it is prepared. Neither this nor the gelatin will resist water. As soon as a macerated skull is rinsed, the teeth that are loose should be taken out one at a time, the socket partly filled with one of the cements and the tooth replanted. In this way the teeth may be kept in their proper places, and as the skull dries the teeth will be firmly fixed. Although the teeth of skulls prepared by the liquid soap process may be loose before the skull is dry, the gelatinized dental periosteum will usually fasten them very firmly as the skull dries. If any of the teeth come out they should be replanted as directed above. Need of Accuracy,—So far as concerns the general aspect of the skull, the incisors may be interchanged, and missing teeth may be replaced by teeth from other skulls. It is to be feared that such substitutions are sometimes made with skulls prepared for sale. Unless the changes are carefully specified, such skulls have no real scientific value as regards the teeth. When two or more of the teeth drop out at the same time, unless direct observation or comparison with a fresh or alcoholic specimen warrants absolute certainty, it is better to keep those teeth in a box separate from the rest. § 252. Preparation of Natural Skeletons.—By a natural skeleton is meant one in which the bones are held together by their natural ligaments. Such a skeleton may be prepared according to either of the processes described above. One must, however, watch that the ants may remove only the muscles, or that, in the process of maceration, only the muscles decay. In all the processes, the muscles are softened or removed first. If the liquid soap process is employed, proceed as follows: Boil the bones in the mixture as directed (§ 248) until the muscles may be removed without much trouble. It will be found necessary, however, to allow the boiling to proceed only to the point where the muscles will separate from the bones by using the hands, a smooth stick like a scalpel handle, ora dull knife blade. The ligaments will be found considerably swollen and somewhat softened. The softened ectal surface may be cautiously scraped off; then the preparation should be soaked for 3-6 hours in a saturated solution of arseniate of soda (about 25 per cent.), to poison the ligaments and protect them from Dermestes. Then the part should be arranged as nearly as possible in a natural. DISARTICULATING SKULLS. 109 position and fastened with pins or strings and allowed to dry. The swollen ligaments will shrink very greatly, so that what might have seemed a very imperfect preparation when moist will be excellent when dry. When the specimen is dry, rough projections of liga- ment may be removed with a sharp knife. Flexible Natural Skeletons.—If it is desired to have the lig- aments flexible, the preparation may be soaked after it is partly dry for from 16 to 12 hours in either Wickerscheimer’s fluid (§ 299), or a mixture of a saturated aqueous solution of arseniate of soda, 4 parts, and glycerine 1 part. § 253. Preparation of the Bones of Young Animals.—The liquid soap process is to be preferred. But during the boiling the bones must be carefully watched, and the boiling should be carried little farther than for making natural skeletons. The epiphyses must not be allowed to separate from the diaphyses. The skulls of new born kittens may be nicely prepared in this way, and the sutures show with great distinctness. § 254. Disarticulating Skulls.—Choose a young or barely mature animal for this preparation, since the cranial sutures are liable to be obliterated in adults. Prepare the skull by the liquid soap process (§ 248). Continue the final boiling for half an hour longer than for a skull that is not to be disarticulated. While still moist, the bones may be separated by steady traction. This may be done with the greatest ease if half grown animals are used. Skulls that have become dry may be boiled for half an hour in the liquid soap to soften the gelatinized connective tissue binding them together. Macerated young skulls may be disarticulated by carefully pulling and prying the bones apart. An excellent plan is to fully disarticulate one side of a skull, and to leave the other with the bones in situ. Disarticulation of Large Skulls.—If a large skull is prepared by the liquid soap process it should be thoroughly softened by soaking in water two or three days or by boiling an hour. Then fill the cranial cavity with dry beans or peas, force a cork tightly into the foramen magnum (Fig. 57) and place the skull in water. The swelling of the peas will force the bones apart. Macerated 110 ANATOMICAL TECHNOLOGY. skulls should be treated as just described, but they need not be boiled. § 255. Bleaching Bones.—In order that bones should be white and clean, it is necessary that they be relieved of all their grease and blood. Neither of these ends is accomplished when the flesh is removed by insects—ants or Dermestes. Both are fairly well accom- plished by proper maceration; and both still better by the liquid soap process. The old method, and the one still largely employed in whitening bones, is to place them where they are constantly exposed to the action of the sun, rain and dew. The following methods are, how- ever, more speedy and satisfactory :— The blood is usually got rid of in the process of boiling or macer- ation. If, however, one wishes to prepare bones in the best possible manner, the entire vascular system may be washed out with normal salt solution. To do this, insert a canula into the arch of the aorta (Fig. 101); open the preecava (Fig. 101) just peripherad of the heart, and then, with a syringe, inject salt solution into the aorta until it runs uncolored from the preecava. See also p. 111. § 256. Freeing Bones from Grease.—There are four ways of removing grease from bones :— A. By suspending them in spirits of turpentine—Oleum terebin- thine rectificatum—(ordinary commercial oil of turpentine will do), for three or four weeks. An indefinite soaking in turpentine will do no harm if the bones are suspended, and more than four weeks may be necessary for large bones. The turpentine should be very fluid. The bones must be suspended so that the thick, oily substance that settles to the bottom of the vessel cannot touch them. After the bones have soaked for a sufficient time in the turpen- tine, they should be exposed to sunlight but not to rain. B. Suspension in denzine (common commercial benzine will do very well). The bones should be treated as directed for turpentine. C. Soaking the bones in sulphuric ether. The bones need not be suspended, simply placing them in the vessel with the ether will be sufficient. The ether dissolves the grease very quickly, so that small bones like those of the cat are entirely freed from grease in a fortnight or even a less time. The bones should be exposed to light as directed above. PRESERVATION OF SOFT PARTS. 111 Ether is expensive, but the use of it for removing grease from bones does not injure it for anesthetizing animals. It is said to render bones brittle. As turpentine, benzine, and ether are very volatile, they must be kept in tight vessels. The preserving jars (Fig. 82) answer very well for the bones and either of these agents, Either of the three preceding methods may be employed for removing grease from natural skeletons. The following method is also good for that purpose, but not quite so safe, as there is some danger of loosening the ligaments, D. Soaking the bones in liquid soap. Place the bones in a dish of liquid soap (§ 248) and let them remain for three or four days, in some cases longer, then wash them very thoroughly with clean water. Dry them and expose them to the sun (§ 256). It is not usually necessary to treat bones that have been prepared by the liquid soap process, but bones that have been macerated or pre- pared by insects may be relieved of their grease in this way. It may be desirable to mix the liquid soap with an equal amount of water and boil for half an hour or more. Peroxide of hydrogen has been found the safest and most rapid agent for bleaching bones. A so-called 12 vol. per cent. solution is mixed with an equal volume of water, and rendered neutral or slightly alkaline by the addition of ammonia or carbonate of soda. The thoroughly dried and degreased bones are placed in this in a closed vessel like a preserving jar (§ 313). The bleaching is usually sufficient in two to five days. It is necessary to keep the peroxide tightly corked and in a cool place to prevent deterioration. THE PRESERVATION OF SOFT PARTS. § 257. Practically, a bone once properly cleaned is imperisha- ble, and needs only to be protected from dust or injury. But all the soft parts of the body are more or less prone to decompose at common temperatures and under ordinary conditions ; even when treated with preservatives, they are liable to deteriorate unless con- stantly cared for. Many agents have been employed for the delay or prevention of decomposition, and for the permanent preparation of soft parts. Personal experience enables us to speak con- fidently of only three—cold, arseniate of soda, and alcohol. A few other agents—brine, methyl alcohol, chloral and Wickersheimer’s liquid—will be briefly mentioned. § 258. Cold—Decomposition is prevented by a temperature of 0 C. (82 F.), and is more or less retarded at temperatures between 0 and 10. Cold may be employed alone for freezing specimens so as to keep indefinitely ; more 112 : ANATOMICAL TECHNOLOGY. often, decomposition is simply retarded by it, while the specimen is temporarily protected by arseniate of soda or permanently preserved by means of alcohol. Frozen sections and dissections will be discussed later in this chapter. § 259. Arseniute of Soda—Sodium Arsenias.—A saturated solution of this poisonous salt may be used for the injection of specimens which are to be dissected fresh, or for the poisoning of inflated preparations. Water dissolves about one fourth of its weight of arseniate ; hence the saturated solu- tion is 20-25 per cent. It should not be allowed to remain upon the dissector’s skin longer than necessary. Here and elsewhere, when a solution or mixture is mentioned, the menstruum is water unless the contrary is stated. ALCOHOL. § 260. Alcohol is almost essential in practical anatomy; its qualities are active, and its management requires constant care. General Description.—The alcohol commonly employed for Natural History purposes is, strictly speaking, ethylic alcohol, and a member of a group including several others, the amylic, butylic, propylic, methylic, etc. The last named variety will be mentioned again in § 298. Ethyl alcohol is colorless, volatile, and inflammable; it has a vinous odor and pungent taste; it coagulates albuminous sub- stances and extracts more or less water from organisms immersed init. Its composition is C,H,O. Its specific gravity is 796. Absolute Alcohol.—The foregoing statements as to composition and specific gravity really apply only to pure or absolute alcohol, that is, alcohol which has been freed from water and all impurities. This, however, is quite expensive (about $8.00 per gal.), and is required only for some histological purposes. Ordinary or Commercial Alcohol contains from 5-60 per cent. of water. Most of these mixtures are commonly called alcohols, but some of the grades have also special names, as indicated upon the following Table :— § 261. TABLE OF SPECIFIC GRAVITIES OF DIFFERENT PERCENTAGES OF ALCOHOLS AT 155° C., 60° F. 100, .796, Absolute alcohol. 84, 838, Spiritus rectificatus, Br. 95, .809, [Commercial alcohol.] 75, 860. 92, £817, Alcohol fortius, U. 8. 60, .896. 89, 825, Lightest spirit obtained by ordi- 60, .917, [Strong liquors, whisky, etc.] nary distillation. 49, .920, Spiritus tenuior, proof spirit, Br. 85, 835, Alcohol, U. 8., spiritus rectifica- 89, .941, Alcohol dilutum, U. S. tus, rectified spirit. United States Dispensatory, 13th edition, 1880. See also Watts, A, and Baley, A. Alcohol as received from the warehouse usually contains about 95 per cent. of absolute alcohol; but that which has been kept for some time, especially if frequently exposed to the air, is apt to range from 90-94 per cent., on account of evaporation and the absorption of water from the air. ALCOHOL. 113 The strong liquors—brandy, gin, rum, and whisky—contain from 45-55 per cent. of absolute alcohol. A mixture containing less than 20 per cent. is not directly useful in zoology. § 262, The Leading Characteristics of Alcohol.—Ethy] alcohol has twelve prominent characteristics, of which one half are desirable and the other half undesirable from the zoological point of view :— It is simple, cleanly, colorless, and fragrant, generally obtain- able, and—as a preservative—absolutely efficient. On the other hand, it is costly, volatile, inflammable, and decol- orant, quick to absorb water from the air, and—under certain con- ditions—corrosive of some metals. § 263. Alcohol should be used with discretion, always closely covered, secured from fire, and kept in vessels of glass, hard wood, copper, zinc, or galvanized iron. 8 264. The Cost of Alcohol.—This, of course, is an extrinsic feature, and varies much in different parts of the world. In most civilized countries, to the actual cost of its pro- duction is added a heavy government tax, and the retail price in the United States is about $2.50 per gallon, or 50-75 cents per liter. This high price of the liquid best adapted for the preservation of specimens has directly and seriously retarded all anatomical and zoological progress. At various times between 1866 and 1879, at the request of the late Prof. Louis Agassiz and others, with the co-opera- tion of the Hon, 8. Hooper and others, Congress wisely made provisions (U. 8. Revised Statutes, § 3297), by which, under very stringent conditions and with heavy pecuniary lia- bilities in case of the slightest misapplication, museums and other educational institutions “may withdraw alcohol from bonded warehouses without payment of tax, for the sole and exclusive purposes of use in the chemical laboratory, or for the preservation of Natural History specimens belonging to such institutions.” The cost of alcohol so obtained is about one sixth of the retail price. See Appendix. The instructions for so obtaining alcohol for scientific purposes are printed in 1 No. % Series 7 of the U. 8. Revenue Department, p. 48, which may be had from the Collectors. Since no variation from the prescribed forms is permitted, great care must be taken in making out the application and bond ; those who obtain alcohol annually will save trouble and sometimes serious delay by having the forms printed. After making out the form of the application and bond, and inserting the names of the two sureties, some proprietor of a bonded warehouse should be asked to set aside the num- ber of barrels (40-45 gals. each) of alcohol desired, and to send a memorandum of the marks and other items required in the papers. If the forms are printed, a copy of the application form may be sent, so that the various numbers may be filled in, together with the number of the collection district in which the warehouse is located. This copy should be retained for reference in making the assurance afterward required. The papers should then be promptly filled out, care being taken that the signatures of the sureties coincide as to initials and abbreviations with the names as entered in the body of the bond. The papers are to be transmitted to the Commissioner of Internal Revenue through the Collector of the district in which the institution is located. If the papers have been properly made out, the permit may be received within ten days. No form is prescribed for the assurance of the Revenue Department that the alcohol 8 114 ANATOMICAL TECHNOLOGY. has been used for the prescribed purposes within the specified time. It is necessary to make oath before the proper officer to this effect, giving the marks of the alcohol and the date of the original application. ‘This atlidavit is to be transmitted to the Commissioner of Internal Revenue through the Collector of the district in which the institution is located. Since it is not always easy to ascertain the location of warehouses, it may be proper to mention that alcohol may be obtained promptly under the foregoing conditions trom Messrs. E. N. Cook & Co., of Buffalo, N. Y., who also furnish blanks, § 265. Inflammability—At ordinary temperatures—15-20° C—a mixture of alcohol and water containing 30 per cent. or less of absolute alcohol cannot be ignited, and promptly extinguishes a lighted match dipped into it; 35 per cent. ignites with difficulty, and the flame is extinguished by the lightest current of air; 40 and 45 per cent. ignite more readily, but burn gently and slowly. Even 65 per cent. does not burn fiercely, and the flame is easily extinguished. Specimens saturated with alcohol are more combustible in proportion to the strength of the alcohol. Other Inflammable Substances. —Still more volatile and inflammable are the ether, ben- zine and spirits of turpentine which are used in anatomical work. § 266. Precautions against Fire.—Alcohol, benzine, ether, and spirits of turpentine in bulk should be stored in a fire-proof vault, or in some small building apart from valuable collections and apparatus. In the laboratory there should be not more than 20 liters of 95 per cent. alcohol, and of the other liquids only enough for current uses. All of them should be kept in glass or copper vessels, well stoppered and at a safe distance from all lights and heating apparatus. They should never be opened within one meter of a light, and if there is a current of air toward the light, the distance should be at least doubled. When removed from alcohol for examination or dissection, specimens should be washed off with water, and kept wet with the 15 per cent. glycerin solution, as directed elsewhere. This precaution is the more essential when anatomical work is done by artificial light. Cotton and cloths which have been saturated with alcohol or other inflammable liquids should be dried on trays in the sun or wind rather than near a fire. Common cotton should be thrown away after use in alcohol, but absorbent cotton may be saved if thor- oughly dried. Safety matches are to be preferred. All matches should be kept in metal or glass boxes. After using, matches should be put into a glass or metal receptacle, and never thrown on the floor. Smoking in a laboratory where alcohol is used should be absolutely forbidden. § 267. Determination of the Percentage of Alcohol in an Alcoholic Liquid.—This may be done by means of either a Speci- fic Gravity Hydrometer or an Alcodmeter (alcoholometer). For zoological purposes the latter instrument is more convenient and sufficiently exact. § 268. Alcodmeter (alcoholometer).—This is a form of hydrome- ter or areometer especially adapted to determining the volume or weight percentage of alcohol in a mixture of alcohol and water. It is a graduated tube, loaded so as to rest vertically in any liquid capable of floating it. The alcodmeter of Tralles is com- monly employed in this country ; it indicates the vo/ume per cent. In pure water the instrument sinks only to zero, the lower end CHANGING THE PERCENTAGE OF ALCOHOL. 115 of the scale. In absolute alcohol it sinks to 100, the upper end. Mixtures of the two liquids permit it to sink to various depths, and the number corresponding with the surface of the liquid indicates the percentage of alcohol by volume. A. Alcohol that has been used for the preservation of specimens usually holds in solu- tion or suspension substances of greater specific gravity than alcoho] or even water. Their presence increases the specific gravity of the liquid, and causes the per cent. of alcohol to appear less than it really is. Old alcohol should therefore be cleared (§ 294), if necessary, before testing with the alcodmeter; but filtration will not, of course, remove materials which are in real solution. B. As stated by Giinther (§ A, 697), the British hydrometer is so arranged that the zero corresponds with proof spirit, about 49 per cent. The other grades are designated as so many degrees above or below proof, and two degrees equal but one per cent. For example, our 95 per cent. alcohol would be 92 above proof, while 20 below proof would indicate the presence of 39 per cent. of absolute alcohol. § 269. Hydrometer Jar.—This is a tall and narrow glass jar, mounted on a foot. The alcohol to be tested is poured into it, and the scale may be read through the glass. Any glass jar of sufficient height (e. g. the 3x 10 in. jar of Whitall, Tatum & Co., A), will answer in using the alcodmeter, but the narrowness of the proper hydrometer jar requires a less quantity of the liquid, and the scale is read more easily. A cylindrical graduate on a foot, and holding about 500 cc., makes an excellent hydrometer jar, but is more expensive. Finally, a cheap one may be made by corking one end of a tal] lamp chimney or piece of large glass tubing, and fixing it into a hole in a wooden disk. Unless care is sure to be observed in introducing the alcoémeter, a piece of soft sponge or some cotton should be pushed to the bottom of the jar. § 270. Changing the Percentage of Absolute Alcohol in a Mixture.—This may be done by mixing two grades of alcohol, or by adding water to one of them. The due proportions may be ascertained either by experiment or by the arithmetical method known as alligation alternate. § 271. Rule of Alligation Alternate.—Find the difference be- tween the required per cent. and the per cent. of each of the liquids to be combined. Write the reciprocal of each of these different numbers, and reduce the fractions to a common denominator. The numerators will then represent the proportionate volumes of the two liquids. Examples.—W ater and 95 per cent. alcohol are to be so combined that the per cent. of the mixture will be 50; 95 — 50 = 45; 50 — 00 (the water) = 50. The reciprocals of the two numbers are 7; and ;1,; reduced to a common denominator, these fractions become rio and 79, respectively ; hence 9 volumes of water are to be added to 10 volumes of alco- hol. On the alcodmeter the per cent. of the mixture will be indicated as about 55. Again, two grades of alcohol, respectively 75 and 30 per cent., are to be combined so 116 ANATOMICAL TECHNOLOGY. that the per cent. of the mixture shall be 50; 50 —30= 20; 75 —50 = 25. The recipro- cals are , and #;; reduced to a common denominator, these fractions become 7%, and tis, consequently 5 volumes of 30 per cent. alcohol are to be added to 4 volumes of 75 per cent. in order that the per cent. of the mixture may be 50. Upon the alcodmeter the per cent. is about 52. Owing to the unequal specific gravities of alcohol and water, and the contraction which occurs when they are mixed, the results obtained by this method are only approximate, as indicated by the alcodmeter. They are, however, sufficiently close for most purposes. When liquids of different specific gravities are mixed, they should be thoroughly shaken together before testiug with the alcodmeter. § 272. Determining the Ratio by Experiment.—When a given volume of alcohol is to be made either stronger or weaker, the end may be reached experimentally in either of two ways: The entire volume of the alcohol to be changed may be placed in a jar, and the modifying liquid —whether water or weaker or stronger alcohol— may then be introduced gradually until the desired per cent. is attained ; or a given volume of the alcohol to be changed may be placed in the hydrometer jar, and given volumes of the other liquid induced. Having ascertained the ratios, larger volumes may be mixed accordingly. In both these cases, the two liquids must be thoroughly shaken or stirred together before testing. § 273. Reduction of 95 per cent. Alcohol by the Addition of Water._Since this is the change most frequently made, we have ascertained by the alcodmeter the results of the mixture of water and alcohol in various simple ratios. These ratios are given in the following Table :— VOLUMES, VOLUMES. REQUIRED PER- REQUIRED PER- CENTAGE. CENTAGE. Alcohol]. Water. Alcohol. Water. 84 6 1 55 1.1 1 82 5 1 48 1 1 78 4 1 45 1 1.25 via) 3 1 42 1 1.5 67 2 1 35 1 2 62 1.5 1 30 1 3 60 1.25 1 22 1 4 59 1.2 1 § 274. Water to be Mixed with Alcohol.—If the mixture is for the hardening or storage of specimens, any clean water will answer. But if for the exhibition of finished prepara- tions, the water should be either distilled, or rain water filtered; otherwise the mixture is liable to be clouded, THE ECONOMICS OF ALCOHOL. 117 § 275. The Economics of Alcohol.—In the economical employ- ment of alcohol, four matters are to be considered: (1) The use of different grades for appropriate purposes; (2) The prevention of evaporation ; (3) The avoidance of leakage; (4) The improvement of ‘‘old”’ (deteriorated) alcohol. § 276. The Use of Appropriate Grades—Upon zoological specimens alcohol is em- ployed for three distinct purposes: preparation ; storage ; exhibition. Different degrees of clearness and strength are needed for these different purposes, and the safety of speci- mens, economy, and the appearance of collections depend upon the use of each grade for its appropriate purpose. For example, the commercial (95 per cent.) alcohol is just strong enough for some purposes, much too strong for others, and needlessly clear and pure for others. The following remarks apply to all vertebrates, and the more general ones to most invertebrates also. Among the invertebrates the jelly-fishes and some other soft forms cannot be satisfactorily preserved by means of alcohol, and most of the rest should be treated like the brains and embryos of vertebrates. § 277. Strong alcohol coagulates the tissues so as to form a firm ectal layer, through which it afterward passes with difficulty. With a small specimen, the only objection may be the corrugation and distortion of the specimen. But with a large and fleshy one, ie outside may harden while the interior is actually decomposing. There is no difficulty in preserving the skeletal muscles and the limbs, but the brain and abdominal viscera, especially the liver, are not only more prone to decomposition than the muscles, but naturally excluded by them from the alcohol. Unless, therefore, definite measures are taken prior to immersion (§ 286), some of the viscera will surely fail to be preserved. These measures will vary according to the size of the specimen and the use to be made of it, and, under some circumstances, the opportunity for using the required instruments. § 278. The four accessory measures are named in the order of their simplicity: (1) Freely opening the abdomen; (2) Injecting alcohol into the thorax and abdomen; (8) Injection of alcohol into the large hollow viscera ; (4) Injection of alcohol into the arteries. § 279. As a preliminary to any of them, the animal should be bled, if practicable, while under the influence of an anesthetic. As soon as the cat is quite asleep, the femoral vessels may be exposed as directed for coarse injections (Fig. 39). and the V. femoralis divided. When the venous flow slackens, the artery may be opened. In this way most of the blood in the larger vessels is removed, and preservation is facilitated. 118 ANATOMICAL TECHNOLOGY. § 280. (1) Freely Opening the Abdomen.—This is sometimes, as when collecting in the field, the only practicable method. The ab- domen is opened by a longitudinal incision a little dextrad of the meson, never—as commonly directed—on the meson itself. A sec- ond incision is to be made at a right angle with the first, extending to the dextral margin of the abdominal cavity; these two incisions © are shown in Fig. 76, but the transverse one should not cross the meson. The specimen is to be placed in 52-67 per cent. alcohol, the hand introduced, and the viscera lifted and moved slightly, so as to per- mit the penetration of the liquid to all parts; cotton may be inter- posed. The diver especially should be displaced, and—unless its preservation is especially desirable—most of it should be removed, the cholecyst (gall bladder) being left. _ § 281. This method is much more efficacious if combined with the third, as follows :— The rectum is compressed so as to expel its contents per anum, and the small intestine treated in like manner, if its contents seem to be considerable. The stomach is manipulated and compressed. so as to expel its contents through the mouth. A slit about 1 cm. long is then made in the free surface of the duodenum near the stomach, and alcohol injected, first through the pylorus into the stomach, and then into the small intestine, so as to fill both it and the large. The escape of the alcohol from the anus may be pre- vented by a plug of cotton. For all injections of alcohol, a rub- ber bulb syringe is more convenient than one with a piston. After injecting, it should be thoroughly rinsed out with water. The lungs may be filled with alcohol by passing a curved canula attached to a rubber tube from the mouth through the glottis, or by opening the trachea. § 282. (2) Injection of 52-67 per cent. Alcohol into the Thorax and Abdomen.—This is less efficacious than the other methods, but may be adopted when it is desirable to mutilate a specimen as little as possible, as in making a permanent preparation of an entire animal. / The incisions for the introduction of the canula should be made obliquely, so as to leave a valvular orifice which is less apt to per- mit the escape of the injected liquid. Both sides of the thorax should be injected. Of course this method is more efficacious if combined with the third. INJECTION OF ALCOHOL INTO THE ARTERIES. 119 § 283. (8) Injection of 52-67 per cent. Alcohol into the Stomach, Intestine, and Lungs.—If the left hypochondrium is prominent, or if itig known that there is much food in the stomach, the entire abdomen should be compressed, so as, if possible, to expel the con- tents through the mouth. Pressure of the abdomen just cephalad of the pubes will probably expel part of the contents of the large intestine, and most of the rest may be washed out with water intro- duced from a syringe or from a faucet. Alcohol should then be injected into the abdomen, as directed in § 282, or the cavity may be opened, as directed in § 280. In the latter case, both the stomach and small intestine may be filled from the duodenum. In the former, alcohol may be injected into the large intestine through the anus, and into the stomach from the mouth. The anus should be plugged with cotton to retain the alcohol ; if the stomach is filled only moderately, the alcohol will probably be retained by it. The lungs may be filled in either of the two ways mentioned in § 281. Of course, neither of the three measures above described is of direct service in preserving the membral muscles or the brain. These parts are immediately reached by the alcohol only according to the fourth method, which is efficacious for all parts, but somewhat more complicated than the other methods. § 284. (4) Injection of Alcohol into the Arteries.—This should be done in all cases when practicable, or unless there are special objections. With entire animals, or the cephalic or caudal halves, there is no practical difficulty ; with smaller portions, as the head or a single limb, it may be necessary to tie or secure with compress- ors other vessels than the one injected, so as to prevent the escape of alcohol; but in some cases even this may be omitted, the injec- tion being done in a dish, so that the escaping alcohol is saved. The following directions apply particularly to the cat:— If the entire animal is to be preserved, provide at least 2 liters of 84-95 per cent. alcohol and a syringe and canula of appropriate size. After bleeding (§ 279), close the vein by a ligature both cen- trad and peripherad of the point of division, and have ready a small compressor for application to the artery. Inject the alcohol into the A. femoralis, as directed for plaster (see Chap. III.). Inject the alcohol slowly, so as to give it time for penetrating the smaller vessels, and stop as soon as the resistance is decidedly increased, lest the vessels be ruptured. This last precaution is indispensable if a plaster or gelatin injection is to be made afterward. 120 ANATOMICAL TECHNOLOGY. Place a small compressor on the artery just centrad of the point of injection, and withdraw the canula. At least two hours should elapse before dissection is begun or an injection made with plaster or gelatin. In the interval the hair may be clipped (see Chap. VL). After clipping, if no other injection is to be made, the animal may be placed in alcohol, 42-55 per cent. § 285. If only the cephalic half of the body is to be preserved, not more than one liter of alcohol may be needed, and the operation of abdominal transection should be carried as far as to open the abdomen and puncture the diaphragm (§ 238). Then, in place of removing the viscera at once, proceed as fol- lows :— Grasp the rectum as far caudad as possible, and force its con- tents cephalad. Place two ligatures on it (Fig. 41), about one cm. apart, and cut between them. With the scissors and tracer divide the mesentery of the large intestine and that of the small intestine, to a point opposite the cephalic end of the left kidney (Fig. 101, ve). Pass a strong thread from this point around the stomach and liver, 1-2 cm. from the diaphragm, and tie it very firmly. The lig- ature should cut deeply into the substance of the liver. With the tracer expose the aorta opposite the caudal end of the left kidney. Open the aorta as directed (Chap. IV.) for the A. femoralis. Inject alcohol as directed (§ 284) ; then inject alcohol into the lungs as directed in § 281. Remove the abdominal viscera by an incision 1-2 cm. caudad of the ligature, taking care not to displace the latter. § 286. Treatment of Special Organs and Tissues.—The blood should be washed off with water or weak brine. Very vascular parts, like the liver or spleen, should be gently manipulated so as to expel most of the blood. In respect to the strength of alcohol required, the soft parts form three groups, as follows :— Brains, embryos, the liver, spleen, the glands, and most inver- tebrates should be laid upon cotton in natural attitudes, first in alcohol of 52-67 per cent. ; after two days in 95 per cent., fora week ; lastly, for exhibition or storage, in 75-95 per cent. Muscular organs, including the heart and alimentary canal, may be hardened and permanently preserved in 42-55 per cent. The same strength is adapted to most entire animals. AMOUNT OF ALCOHOL REQUIRED. 11 Ligaments, bones, and cartilages should be placed in 42-55 per cent. for two days, and then kept in 22-80 per cent. When the same specimen contains two or more of these kinds of organs, the strength of the alcohol should be adapted to the more perishable, provided these latter are to be fully preserved. For injection into the viscera or abdomen, 52-67 per cent. ; for arterial injection, 84-95 per cent., is to be preferred, but any strength above 30 per cent. would be of some service. While hardening, specimens should be kept in a cool place. § 287. Fresh Specimens should not be in contact with the sides of the vessel. In order that all parts may be reached by the alco- hol, the specimen should be suspended so as to hang freely, or cot- ton or ‘‘excelsior’’ interposed between the jar and parts which would be in contact with it, or the specimen jar laid upon one side, and shifted daily for a week, so that no part of the specimen is in contact for more than 24 hours. With well-preserved specimens, this precaution need not be observed. § 288. Hlexible Specimens.—If it is desirable that flexible spe- cimens should harden without contortion, they should be suspended from the cover of the jar, or the jar itself laid upon the side, as sug- gested in § 287; it is safer to place the jar upon a tray. The mouth end should be slightly raised and very securely closed. § 289. Amount of Alcohol Required.—With fresh specimens the alcohol should not be less than twice the volume of the specimen. The results are more satisfactory if the ratio isas 4:1. The smaller amount may be more safely used with specimens when alcohol has been injected into the arteries (§ 286). A. Specimens which have been once saturated with alcohol may be stored or placed on exhibition in the minimum quantity required to cover them ; in this way a single jar or can may hold a large number of specimens. But fresh or partly preserved specimens, especially of viscera, should have plenty of space and abundance of alcohol. Neverthe- less, experienced collectors are sometimes led to fill a jar with fresh specimens, in the hope, apparently, that the inevitable laws of decay will be overruled in their favor. In most cases, a single well-preserved specimen is of more value to science than ten which have been insufficiently cared for. Whut ts worth preserving at all is worth preserving well. B. With museum specimens, and for exhibition, the odor of the alcohol is less impor- tant; but the clearness and strength are essential. C. Old alcohol, whether filtered or not, may be used for storage, and for the pri- mary treatment of some fresh specimens. § 290. Provisional Preparations.—It is not always possible or even desirable to make the final preparation of a part upon a fresh specimen, or immediately upon the reception of one in alcohol. In 122 ANATOMICAL TECHNOLOGY. these cases, however, if the scope of the final preparation is deter- mined, most of the parts not involved may be removed at once, thus saving alcohol or storage room, and—if the specimen is fresh—insur- ing the more complete access of the alcohol. This measure is par- ticularly important in the case of viscera or massive muscular organs, and especially the brain of large animals and man. Even with the brain of the cat, if the aulic region, for instance, is to be examined, it is well to remove the dorsal and lateral parts of the hemispheres. § 291. Deterioration of Alcohol.—During its use upon speci- mens, alcohol is subject to four kinds of deterioration :— It may become colored by solution of coloring matters ; turbid from the suspension of small particles; offensive from the solution of malodorous matters; and weak from the evaporation of the pure alcohol, the impartation of alcohol to the specimen, the ab- straction of water from the specimen, and the absorption of mois- ture from the atmosphere. § 292. Purification —Aside from distillation for the sake of strengthening, alcohol may be purified and improved in three ways: settling ; filtration for clearing ; filtration for deodorizing. §$ 293. Settling.—Let the alcohol stand for a few hours undis- turbed. Place a second jar close to it, so that the first need not be carried, and pour the alcohol into it very carefully, and without reversing the tilt until the dregs begin to approach the mouth. If the alcohol is less than 20 per cent., or if the dregs are very foul, they should be thrown away. But usually the dregs should be poured into a more slender jar, and allowed to settle a second time. § 294. Filtration for Clearing.—W hen alcohol is simply some- what turbid, as usually is the case after the settling, or if its in- tended use does not require deodorizing, the following process is sufficient: Push some cotton into the narrow part of a large tunnel, set the tunnel into a jar, and cover it closely. According to the compactness of the cotton will the alcohol filter through more or less rapidly, and with greater or less change of color and clearness. The same cotton should not be used a second time. A. Clearing may be effected at the same time with deodorizing, if the perforated lid of the filter to be described is covered with muslin, and if one or more layers of muslin are so placed that the alcohol must pass through them before reaching the animal charcoal. B. During the filtration of alcohol, unless it is conducted into a receiver with a mouth just large enough to receive the discharging end of the funnel, or the tube connected therewith, let these pass through a hole in a metal, wooden, or pasteboard cover of the jar. ALCOHOL VAPOR. 123 § 295. Liltration for Deodorization and Decoloration.—This requires the use of animal charcoal, and should follow the settling and clearing already described. Any kind of water filter containing animal charcoal may be used, but the simpler and cheaper forms are sufficient, and the char- coal should be capable of renewal. Such is the earthenware filter made for water under the direction of our colleague, Prof. A. A. Breneman, and for sale by Messrs. Rankin & Son of Ithaca. Un- less the alcohol is clear, the perforated lid should be wrapped in a cloth, and two or more layers of cloth placed over the top of the fil- ter, resting on the lid, so that the alcohol may be cleared of sus- pended impurities before it reaches the charcoal. In the absence of a proper filter, a bag of the charcoal may be pushed firmly into a large tunnel ; the tunnel for this purpose should have the smaller end larger than usual. § 296. Crystalline Deposits—From some specimens, especially brains, strong alcohol extracts substances which are precipitated as white crystals when the percentage of alco- hol is diminished or the temperature lowered. The resulting turbidity and clouding of the glass require a thorough washing of the specimen and the jar, and the renewal of the alcohol. The old alcohol should settle in a cool place, and then be filtered through cotton. Even after filtering, it should be used only for hardening and storage. When two grades of “old alcohol,” whether filtered or not, are mixed, the deposits above mentioned are liable to occur ; hence, if a clear mixture is desired, a trial should be made first with small quantities of the liquids. § 297. Strengthening.—So far from increasing, the strength of alcohol is likely to be reduced by the processes of filtration and settling, especially unless precautions are taken against evaporation. A slight improvement may be effected by treatment with quick- lime, and distillation is, of course, an efficient means. The readier method, however, is simply to add to the weaker spirit enough 95 per cent. alcohol to impart to the mixture the required strength ($$ 271, 272). When alcohol is purchased at retail, none should be wasted. But if it is obtained free of tax, it is sometimes cheaper to throw away the weaker grades, especially the dregs after settling, rather than to spend much time in their improvement. § 298. Alcohol Vapor..—The antiseptic and preservative prop- erties of the vapor of alcohol may be utilized in two ways :— (1) Upon Fresh Specimens.—When a fresh specimen is to be dissected somewhat rap- idly, say within one week in warm weather, or two or three in cold, it will keep with little change if placed in a close vessel at the bottom of which is enough 95 per cent. alco- hol to keep the atmosphere completely saturated with the vapor. In these cases the skin should be removed only as needed, and the exposed parts covered, when not under exam- ination, with cloths wrung out in alcohol. (2) Alcoholic Specimens.—Any specimen which has been acted upon throughout by alcohol will keep almost indefinitely in the vapor. Hence, in some cases, especially where a specimen is under daily dissection, after it has been fully saturated with alcohol, the 124 ANATOMICAL TECHNOLOGY. latter may be poured off, and a small amount of strong alcohol left at the bottom of the ar. ; In this case, however, if water or the wetting liquid has been applied to the specimen, a little alcohol should be poured over it whenever it is returned to the jar, or that which is already at the bottom may be shaken up so as to moisten the surface. § 299. Methyl Alcohol.—This is more often called wood spirit or wood naphtha, Its odor is unpleasant, and it is not used as beverage. In England it is said that no tax is imposed upon a mixture containing 11 per cent. of methyl alcohol. In this country it is not subject to tax, but costs about $1.50 per gallon. According to Giinther (A, 697), it is less efficient than ethyl alcohol as a preservative, at least for fishes. Hence, when ethyl alcohol can be had free of tax, there is no object in using the methylic variety ; even when the former costs its full retail price, unless large quantities were wanted, the saving in cost would hardly compensate for the unpleasant smell of the wood spirit. § 300. Wickersheimer’s Liquid.—Several formule for making this preservative have been published in this country, as, ¢. g., in ‘“The Popular Science Monthly,’’? March, 1880, p. 717; ‘‘ The Med- ical Record,’’? April 17, 1880, and April 30, 1881, p. 501. In the last named, it is stated that the original formula has been altered, and that Messrs. Poetz & Flohr of Berlin prepare two kinds, one intended for injections, and the other for immersing bodies. Their composition is as follows :— Injection. Immersion. Argenious acid... . 6... .. cece ence eeeee 16 grams. 12 = grams. Sodium chloride...................0. 80 “ 60 as Potassium sulphate...............00.. 200 ef 150 a Potassium nitrate... ....... 2. eee eee eee 25 as 18 o Potassium carbonate......... cee eee 20 ef 15 se Watery cccti2 2 ces otcahenanewinad Ahoy 10 liters. 10 liters. GUY COTE ees fase o ewawel aca guiend xa 4 e 4 ee Wood naphtha .............. 222.0008 HS ve According to the previous article in the ‘‘ Record,” the various salts are to be dissolved in the boiling water, and the solution is to be cooled and filtered before the other two liquids are added. It is probable that the cheaper glycerin will answer, and that ordinary (ethyl) alcohol is to be preferred to the methylic variety which is specified. Application.—Preparations that are to be preserved dry are immersed in the liquid for 6-12 days according to size, and then dried in the open air. Hollow organs, like the lungs, must be filled with the liquid, then laid in a vessel of the same, and afterward distended with air and dried. Our own experience with this liquid does not enable us to give a decided opinion as to its merits. We are disposed to think that it will answer a good purpose with preparations of the ligaments, and of hollow viscera where flexibility is desired. With dry inflated preparations, the cheaper and simpler arseniate of soda is equally efficacious, while all ordinary ‘‘ wet preparations” are, in our opinion, more surely and conveniently preserved by alcohol. § 301. Chloral Hydrate.—A solution of this substance has been used by Dr. W. W. Keen and some other anatomists. The results seem to be satisfactory in most respects ~ TEMPORARY STORAGE. 125 so far aS concerns man and other Vertebrates, but less so with the Invertebrates, at least as reported by Prof. A. E. Verrill in a letter to Dr. Keen. Dr. Keen has published two papers upon the subject (1 and 2), and kindly permits us to print the following brief statement of his experience up to November 1, 1881 :— “ As to the strength of the solution, I should use 20-30 grains to the ounce of water. [This is 4-6 per cent., or in the proportion of 1 gram of chloral to 24-16 cc. of water.] For the Invertebrates and for vegetable tissues, my own experience, though limited, is favorable, It preserves vertebrate organs, excepting the brain, for a few years at least. I have had no failure, and some of my specimens are now nine years old. The colors are rather less affected than by alcohol. The jars do not need to be hermetically sealed, hence the specimens are always accessible. The specimens are also less apt to dry when exposed. The cost of the solution is much less than that of alcohol on which the tax is paid. For the preservation of human subjects for dissection, it is most excellent, excepting that it will not keep them very long in hot weather, and is not well adapted for keeping them over the summer. For use in cool and cold weather, and especially for the dissection of nerves, it holds its own.” The foregoing statements from so distinguished an anatomist certainly warrant a care- ful trial of chloral; our own experience is as yet too limited for the publication of the results. § 302. Brine.—A saturated solution of rock or dairy salt is sometimes used alone for the temporary preservation of anatomical material; it is said to be more efficacious when the specimen is previously injected with a saturated solution of arseniate of soda. In one of the leading medical schools of this country this plan is successfully and economically followed for keeping human subjects even through the summer months. § 303. Exhibition and Storage of Alcoholic Specimens.—As was stated in § 262, while alcohol is a perfectly efficient preservative so far as concerns all vertebrates, its cost, volatility, and corrosive action necessitate certain measures which may be conveniently dis- cussed in connection with the general subject of the storage and exhibition of specimens. § 304. Temporary Storage.—For this purpose, and for brief transportation, alcoholic specimens may be placed in vessels made of wood or earthenware or any kind of metal; but vessels so em- ployed should be carefully examined as often as once a month, so as to guard against evaporation, leakage, or rusting. Leakage or evaporation are readily detected from the diminution of alcohol or the dampness of the bottom of the vessel or of the floor, but rusting may not be apparent until] loss or damage has occurred. When alcoholic specimens are kept in tin ware, the metal is certain, sooner or later, to be corroded at some point of contact with a specimen. A mass of rust is formed which may prevent the escape of the alcohol so long as the speci- mens are undisturbed. But this rust is liable to be dislodged by any movement, or even by a blow upon the side of the vessel, and thus permit the escape of the alcohol. § 305. Leakage from Imperfect Glass Vessels—Small jars and vials sometimes have small holes or cracks which escape notice at the time of filling, but which permit the loss of alcohol and the damage of the contents. In some cases, part of the bottom of a small jar may be so thin that it is pulled off by simply adhering to the paint of a shelf. 126 ANATOMICAL TECHNOLOGY. § 306. Corks should be used only for brief transportation or temporary storage. The best of them are insufficient barriers against either evaporation or leakage, and the poorer ones should not be used at all with specimens. Corks may be rendered more secure by soaking in oil, or covering over with vaseline, or with a solution of paraffine in benzine, benzole, or turpentine. Rubber stoppers are sometimes used. § 807. Glass Dishes and Boxes—The anatomist lias use for glass dishes of almost every size. A few sizes are kept in stock by Messrs. Berge (A, No. 257), and Whitall, Tatum & Co. (A, No. 2265). Covers for them may be cut from window glass, or these or other sizes way be ordered to have the edges ground for the reception of covers ground near the edge. The covered box shown in Fig. 31 is very useful for the hard- ening of brains and other small specimens. The largest size ad- vertised by the firms above mentioned (Nos. 202 and 2590) has a capacity of nearly 500 cc., and costs $3.80 per dozen. The covers of these boxes and dishes do not fit accurately, and their contents should be under constant supervision. § 308. Metal Boxes.—As the name implies, the box usually differs from the jar or the can in its relatively greater horizontal extent and in having a cover which is coextensive with the box, and is readily removed and replaced. The accessibility of the contents thus compensates partly for the evaporation of the alco- hol which must occur in some degree. The cover should fit closely and have a wide flange, but such a box should be under constant supervision. Large boxes should be supported by an outer box of wood. For the preservation of cats while under occasional examination, a box of galvanized iron may be 60 cm. long, 40 wide, and 25 deep. An entire cat may rest in it lengthwise, and either the cephalic or caudal half crosswise. Around the inside, half way from the bottom, extends a ledge on which may be laid a metal plate perforated with holes 2-3 cm. in diameter. On this plate may be placed a second tier of specimens, which are thus. kept from pressing upon those at the bottom. If preferred, the bottom may contain only alcohol, the vapor of which will suffice for the keeping of the specimens upon the plate, provided they have been already thoroughly saturated with alcohol. The box may be supported upon bosses or upon short movable legs. The cost of such a box is $4-$5. Fie. 31. — COVERED Guass Box; x.25; § 307. § 309. Exhibition or Permanent Storage.—For these purposes, and for transportation occupying more than a month, alcoholic specimens can be safely entrusted only to tightly closing vessels of glass, copper, zinc or galvanized iron. Of course, glass must be used for exhibition ; it is also cheaper than metal for tightly closing vessels, provided the risk of breakage is not regarded. § 310. Metal Cans.—Three kinds of metal cans are useful in connection with alco- holic specimens. For bringing alcohol from the barrel, and for containing the supply for current use, the ordinary five-gallon oil can is well adapted, especially if provided with a faucet from which the alcohol may be drawn into jars without lifting or tipping the can. The small gallon or half-gallon can is desirable for pouring the alcohol into small vials. These cans may be made of tin, but copper is more secure. Screw-top Cans.—For the permanent storage of alcoholic specimens, especially if occa-. sional moving is necessary, copper cans with screw-tops are desirable. They are more EXHIBITION OR PERMANENT STORAGE. 127 expensive than jars of the same capacity, but are less subject to injury, especially during transportation. A convenient size has the following dimensions: Height, 30 cm.; diameter, 40 cm. ; diameter of the orifice, 26cm. ; capacity, 80-35 liters. The rings of the screw-top are made of brass, and should not weigh over 1300 grams. The bottom should be protected from abrasion by bosses. (At the Museum of Comp. Zoology in Cambridge each can is enclosed in a wooden case which facilitates handling and may be used in transportation.) The edge of the cover-ring is notched for the admission of the iron bar with which it is screwed or unscrewed. Such a can costs $10-$12; this is more than the cost of a glass jar of equal capacity, but the latter is liable to break, especially during transportation, while the can is practically indestructible. § 311. Glass Jars.—With the exceptions indicated in the fore- going sections, glass is to be preferred for all alcoholic specimens. Glass jars may be considered in five groups: fruit jars; specimen jars with covers; specimen jars with neck and ground glass stop- pers ; welted jars ; compressed jars. § 312. Fruit Jars—There are many styles of these, but most of them are made of more or less opaque glass. The orifice is seldom more than; 5.5 cm. in diameter. They are thus unsuited for exhibition or for holding wide specimens; but their cheapness and strength adapt them well for the storage and transportation of such specimens as they will contain. Fig. 32.—WipE MoutTHED SPECIMEN JARS WITH COVER; § 312. § 818. Wide Mouthed Jars with Covers—(Fig. 82)—These are made on the general pattern of the “‘ Millville” fruit jar, but are of clear glass, and have mouths nearly as wide as the jars; the cover has a ring from which specimens may be suspended. Messrs. Whitall, Tatum & Co., in addition to what is said in their catalogue (A, 2600), will send a price list of 183 sizes, ranging from 4x3 in. to 23x9. The following special lengths of standard widths have been made by the same firm at the following prices for each jar: 18x3 in., $1.15 ; 28x 4, $2.05; 82x 4, $3.30; these tall jars are provided with a ‘ foot.” These jars are of course less handsome than the glass stoppered kind, but their strength and cheapness well adapt them for museum and laboratory use. 128 ANATOMICAL TECHNOLOGY. § 814. Glass Stoppered Jars.—These are made to order by any extensive glass manu- factory. The Dorflinger Glass Company, White Mills, Wayne Co., Pa., issue a price list of 51 different sizes, ranging from 2x1 in. to 22 x 7. § 815. Welted Jurs—(Fig. 33) With the specimen jars above described, the neck is strengthened by a constriction. This involves one of two alternatives: either the speci- men must be more or less compressed in entering or leaving the jar, or the body of the jar is needlessly large. With some kinds of specimens these are not very serious objections. But with brains and embryos it is desirable that all pres- sure should be avoided, and also that they should be close to the side of the jar. For such specimens the jars should be of uniform diameter throughout, and the requisite thickening at the mouth may be gained by a welt. The size represented in Fig, 83 is adapted to the brain or the heart of the cat.. Its inside measures are 4 cm. wide, and 6 cm. to the lower border of the part which is ground for the stopper. A smaller size of the same height, but only 3 cm. in diameter, is adapted for either half of the brain. Both sizes are made to order by Messrs. Whitall, Ta- tum & Co. for $2.50 per dozen. § 316. Compressed Jars.—The ordi- nary circular jar is poorly adapted for the display of flat specimens like frozen sec- tions and some fishes. Messrs. Whitall, Tatum & Co. have molds for two sizes of compressed jars similar to the photog- raphers’ ‘‘ bath.” They are 15 cm. high and 21 or 12 cm. wide. The larger cost $12 per dozen, and the smaller $6. The tops are level and ground off for thin glass covers, which may be cemented on. The covers cost a small sum in addition to the price of the jars. Fig. 88.—WELTED VIAL FOR THE BRAIN OR Heart OF THE CAT ; slightly reduced ; § 814 § 317. Cleaning Jars—When large enough, jars should be washed on the inside with a sponge. If they will not admit the hand, the washing may be done with a swab made by tying a sponge upon the end of a stick, or with the bottle brushes, one of which is shown in Fig. 34. For long jars and large tubes there are bottle brushes with long handles; or a wire may be attached to the handle of a short brush ; or the ring of the handle may be cut off, DISPLAY OF ALCOHOLIC SPECIMENS. 129 and the end of the wire let into a hole in a stick of the desired length. If the jar is greasy, it may be cleaned perfectly by means of the liquid soap (§ 248). After washing, glass jars should be well rinsed with clean water, and dried with a soft but not linty towel, and finally—if for the exhibition of specimens—polished inside and out with a bit of old silk or chamois leather. is a Ty 46.3 oe ‘ 3 mh SAREE RAT ESET as B y AO A ae Ny Fic. 84.—BorTLe Brusw; reduced; § 316. § 318. Display of Alcoholic Specimens.—Of course the alco- hol should be clear and the jar clean; but as the jars are commonly cylindrical while many specimens are more or Jess compressed, the surface of the specimen is sometimes undesirably distant from the side of the jar, and the image is distorted by the intervening liquid. When the compressed jars mentioned in § 315 are not available, a smaller bottle or jar of clear glass may be introduced so as to crowd the specimen against one side of the jar. The inner jar must be loaded with lead or filled with alechol or water to such an extent as to just sink it in the alcohol. If water is used, the smaller jar must be very tightly closed. See Appendix, § 1456. As a rule, an exhibition jar should contain only one specimen. § 319. Packing Alcoholic Specimens for Transportation.— There are certain precautions of general application, but the details vary according to the nature of the specimens and the conditions of transportation. In most cases the specimens should be packed before the alcohol is poured in, and the vessel should always be filled. Unless a pail is used, or a box or basket with an unmistakable handle, and ‘tThis side up” prominently inscribed, the package should be prepared for any position. In respect to transportation, specimens may be grouped as coarse, delicate, and scaly. Coarse Specimens.—Under this head come most entire examples of the larger number of vertebrates. These, or their firmer parts, may be packed with no precaution other than to fill the vacancies with hay or ‘* excelsior’’ before introducing the alcohol. 9 130 ANATOMICAL TECHNOLOGY. Scaly Specimens.—Most “‘fishes’’ and some Reptiles should be wrapped in gauze or netting, or any porous cloth or soft paper. The wrapper should be secured with a string. Delicate Specimens.—The delicacy may be due to smallness or softness, or to the presence of projecting parts which are liable to injury. The safest way is to put each specimen in a separate vial or jar quite full of alcohol, or in a small box with saturated cotton which may be immersed in a larger jar or can. When several delicate specimens are to be packed in the same vessel, they should be separated by layers of cotton thoroughly saturated with alcohol. After the alcohol is poured in, the jar should stand for an hour at least to allow time for settling. If any occur, more cotton should be put in. Packing without Alcohot—When the time of transmission by mail or express is short, specimens may be safely sent if covered with a layer of alcoholic cotton, then wrapped in rubber sheeting, and packed in a wooden or metal box, or in a vial properly pro- tected. Secure Closure of Vessels.——Always important with alcoholic specimens, this is essential before transportation. In all cases the vessel should be laid on its side or stood upon the upper end after closing, so as to determine the possibility of leakage. The glass stoppers should be anointed with vaseline or fine oil, or a solution of paraffine in benzine or turpentine, and pushed in with a slight screwing motion. The jar should then be rolled in cloth, and the cloth turned tightly over the upper end of the jar and tied down so as to secure the stopper. The covers of fruit jars and specimen jars should be screwed down more firmly than usual. If possible, all jars should stand upright during transportation, and be well packed in hay or other soft material. Welted Vials may be let through holes in a board so as to be supported by the welt. The board may rest on cleets in a box. Packing boxes of tin are usually closed by soldering. When earthen jars are used, the corks should be pushed below the level of the rim of the mouth, and the space filled up with a thick paste of plaster of Paris. § 820. Miscellaneous Suggestions. — Specimens having prominent appendages, whether arms, legs, wings, fins or spines, especially if they are stiff or angular, should be put into jars ¢ail first, so that their removal may be unobstructed. FROZEN SECTIONS. 131 This rule may sometimes require modification, as with some “ fishes” with delicate caudal fins, which might be broken by the pressure. The specimen may be suspended from the cover of the jar, or the tail may rest upon cotton, or, finally, the jar may be of such size as to permit the withdrawal of the specimen tail first. § 821. In some cases, when a delicate or valuable specimen is in a jar or vial with a mouth too small for its easy or safe extraction, the jar should be sacrificed. Place its mouth just over the edge of a waste pail or box, and rap it smartly with a hammer so as to break off the top. In removing the specimen, avoid the bits of glass which may have fallen into the jar. When the glass stopper of a jar cannot be removed in the ordinary way, tap the han- dle on both sides, alternately, with a piece of wood or the edge of a razor-strop. If this fails to loosen the stopper, or if the handle breaks off, the jar may be broken open as directed above. . § 322. In removing large specimens from alcohol, especially if the hair or feathers remain, squeeze the alcohol out with the hands, then suspend the specimen for a short time from a hook over the jar or some other receptacle, and finally rinse it off with a stream of water. In this way some alcohol is saved, drying is retarded, and the dissector avoids the odor and stimulating effect of the vapor of the alcohol. FROZEN SECTIONS AND DISSECTIONS. § 323. Frozen Sections.—These are sections of desired thick- ness made of a specimen which has been frozen hard so that the parts retain their natural relative positions. Such preparations have been made in Europe since 1833, and in some cases they have been preserved as permanent preparations. A series of frozen sections of the head, in the museum of the Medical School of Maine, were made by Dr. Thomas Dwight, and formed the basis of his work on the head (A). See also his more recent work (B). Frozen sections of a cat were made by us on the 21st of Jan., 1879, and were briefly described by the senior authorin 21. The method was as follows :— § 324. The cat was killed with chloroform, the arteries injected with red plaster and the veins with blue. It was then carefully supported in a natural attitude in a box of hay, which was placed out of doors for three days. The cat was then perfectly rigid, and was rapidly cut with a sharp wide-bladed saw into transections about 1 cm. thick. The cutting was done in a cool room, and each section when made was placed upon a glass plate, held under a gentle stream of water, and both surfaces freed from hair and fat particles with a soft nail brush. It was then laid on one side in a dish of 95 per cent. alcohol, and put in a cool place. As the sections thawed, they were hardened by the alcohol so as to retain their form. Each was then mounted in a compressed jar ($ 316). In some cases the viscera were secured from falling out by means of insect pins. The cavities of the heart were better seen after the removal of the plaster. 132 ANATOMICAL TECHNOLOGY. § 825. The foregoing is the method followed in making the transections shown in Fig. 99 and 100. The following modifications may be desirable :— 1, The animal should be bled, when anesthetized, as directed in § 279. 2, Probably sawdust would be better than hay for support during the freezing. 3. The freezing was done in winter, but artificial cold might be produced at any time. 4. More satisfactory results might be reached by making sections of only part of a sin- gle individual. For example, the thoracic transections would be more true to nature if the lungs had been filled with water from the trachea ; this, however, would have spoiled the neck. In like manner the stomach and intestine or other hollow organs could ke distended to their normal size. 5. For the middle region of the abdomen, including the intestines and part of the uterus and urocyst, a more satisfactory result might be reached by filling those organs with water, and keeping up the pressure during the freezing. A sharp broad-bladed knife could be used to transect the abdomen ventro-dorsad, and a narrow-bladed saw used for dividing the vertebre. § 326. Frozen Dissections.—While frozen sections display the actual relative posi- tion of organs which lie in a given plane, they are unsatisfactory for the same reason that microscopic sections often are : it is rare that a complete view is afforded of any aspect of an organ. Hence we believe that for many purposes there should be a combination of freezing with ordinary dissection. For example, with a frozen cat, most of the thorax could be removed with the saw. Then, before thawing took place, all the rest of the tho- rax could be cut or nipped away so as to expose the entire cephalic surface of the dia- phragm, with the cesophagus, great vessels and nerves projecting for a short distance. The pelvic region could then be removed, and the preparation mounted in strong alcohol so as to retain its form. § 327. Fleaible Preparations of Muscles—Dr. Thomas Dwight has published (7) the results of experiments by himself and others. We are unable to contribute anything to the subject. § 328. Preparation of Hollow Viscera.—Aside from preserva- tion like other soft parts, the stomach and cecum, the lungs, the urocyst (urinary bladder), and cholecyst (gall bladder) may be pre- pared by permanent inflation with air or alcohol so as to display their size, form and subdivisions with more or less of their texture. Since the stomach is most frequently prepared in this way, the following directions apply more directly to it, but they may be readily modified for the other organs named. The parts of the stomach are shown in Fig. 81. § 829. Memoval.-—The viscus should be removed from the body as soon as possible after death. If, however, the stomach or ce- cum has been freed from its contents as described in § 283, the removal may be longer delayed. There should be left attached to the viscus a portion of each canal continuous therewith, about 5 cm. long if possible. With large specimens this length may be greater, and with small ones it must sometimes be less. To secure so much of the cesophagus of PREPARATION OF HOLLOW VISCERA. 133 the cat, the diaphragm must be cut through; after division of the tube, a circlet of the diaphragm may be left attached thereto. § 330. Cleansing.—The organ should be manipulated in water so as to expel the contents and dislodge the mucus from the ental surface. When possible, as with the cecum and with the stomachs of some of the lower vertebrates, the organ should be everted. In any case the ental surface should be thoroughly cleansed with a stream of water from a faucet or syringe. If desired, the capacity of the viscus may be measured as di- rected in § 334. Normal salt solution should then be thrown into the organ, and it should be allowed to soak in the same for a few hours, or until the blood is removed. If any part projects above the surface, it should be covered with a layer of absorbent cotton. § 331. Zrimming.—After sufficient soaking, expel the n. 8. s., and place the organ upon a clean tray or dish. Provide two com- pressors or some linen thread, blowpipe, coarse forceps and coarse scissors curved flatwise. Close the free end of the esophagus with a compressor or liga- ture. Into the duodenum introduce the blowpipe, inflate the organ to a moderate degree, and close the orifice with a compressor or liga- ture. If the latter is employed, the orifice may be controlled by the fingers of the operator or of an assistant while the thread is applied. In trimming, the fat and vessels and connective tissue are to be grasped with the forceps, and cut off close to the viscus. The con- vexity of the scissors must be kept toward the organ, and care taken not to wound it with the point of the forceps. The subsequent steps in the operation vary according to the agent—air or alcohol—to be used for the permanent inflation. § 882. Distention with Alcohol.—This is better adapted to the lungs, and to delicate specimens which might not withstand the pressure and manipulation involved when air is employed. Place the organ in 55-75 per cent. alcohol, in a dish, or better in the jar in which it is to be preserved. Cut off the ligatured smaller end, and secure in the orifice the canula of a syringe, or a canula connected by a rubber tube with the canula of a syringe; place a ligature at the orifice; then distend the organ with the same per cent. of alcohol. If a bulb syringe is used, or if the injecting syr- inge is provided with a cock, it is only necessary to tighten the lig- 134 ANATOMICAL TECHNOLOGY. ature at the time of desired distension ; otherwise, the reflux of the alcohol may be prevented by a small compressor. The jar selected should be so large that the inflated organ may swim without pressure against the sides. It may be kept from the bottom either by suspending it by a thread from the loop on the jar cover, or by attaching a piece of cork or a bulb of thin glass. § 333. Inflation with Air, and Drying.—This method is less expensive, but more complicated :— After trimming, cleansing, soaking, and trimming as above di- rected (8§ 330, 331), the organ is to be partly filled with a saturated solution of arseniate of soda (§ 259), and placed in the same. The projecting part should be covered with absorbent cotton, and the whole should be turned at least once. According to size, it should remain in the solution for from 3-12 hours. If left too long, the tissues are gelatinized and rendered incapable of withstanding pressure and manipulation. Expel any liquid contents as completely as possible, and let the organ drain from a clean smooth surface. Select two fine-grained corks adapted respectively to the two ori- fices. With a rat-tailed file girdle each with a furrow at about the middle of the length. Perforate the larger, and fit very closely into it a piece of glass tube projecting about 3 cm. from the larger end. Fill the grooves with mucilage, and secure each cork by winding about it at the level of the groove a string or rubber band. To the glass tube attach a rubber tube. Inflate the organ, and apply a compressor near the glass tube. Put a tack or a small screw-eye into each cork, and suspend the organ from screw-hooks in a natural position, in a warm but not dusty place. If the organ is large, or drags too heavily upon the slender cesophagus and intestine, support it by bands of parchment or oiled paper. Connect the rubber tube with a gas jet, or with the outlet of a gasometer, or other apparatus by which continuous pressure may be made. Remove the compressor, and turn the gas on cautiously, so as not to distend the organ unduly. The escape of gas will be slight, but its accumulation should be avoided, and the place well ventilated. If no artificial means of inflation are available, air may be blown in from the mouth, or injected with a syringe, but in these cases constant attention is required to prevent collapse. TO MEASURE THE CAPACITY OF AN ORGAN. 135 When the organ is perfectly dry, the ends containing the corks may be cut off, and fresh corks secured with mucilage only. In at least one of the corks should be a screw-eye to which the label may be attached, and by which the specimen may be suspended from a screw-hook. Finally, by excising one or more pieces of the wall with a keen scalpel, the position and shape of the orifices may be displayed. A. Dried inflated specimens should be kept free from dust and moisture, in close cases, or boxes or jars. They should not be varnished. B. Inflated preparations which have been dried without poisoning, or have been insuf- ficiently poisoned, may be sprayed with the solution of arseniate of soda by means of an atomizer. This should be done cautiously and over a small area at a time, lest the entire organ collapse. C. According to a paragraph in the “ American Naturalist ” for March, 1881, page 282, “Dry specimens may be freed from parasites by spraying with anhydrous sulphurous acid.” § 334. To measure the Capacity of an Organ.—This may be done in either of two ways :— 1. The organ may be filled with water from a vessel of Known capacity, and the amount measured. 2. The organ may be filled, and its contents allowed to escape into a vessel and then measured. - In employing either method, certain precautions should be ob- served :— 1. The organ should be completely emptied of its contents. 2. It should not be measured until after the cessation of any contraction which may exist at or soon after death. 3. If possible, it should be held by an assistant. 4, It should rest in a dish of water so that the water used in measuring may not exert undue pressure. 5. Since only the capacity of the organ itself is desired, care must be taken to let the water go no farther than the outlets. With the stomach, for example, the pylorus should be closed, and the introduced water should not rise into the csophagus. 6. If the organ is not to be preserved, the pylorus may be tied. But as tying injures the parts, a specimen which is to be preserved may have the outlet held by an assistant or closed by a compressor or by other mechanical means. 7. If the cardiac orifice is large, the water may be poured in. If small, it may be introduced through a tunnel or through a can- ula connected with a syringe. In the one case hydrostatic pressure 136 ANATOMICAL TECHNOLOGY. must be avoided, and in the other no more force should be used than will suffice to propel the water very gently. 8. If the contained water is to be measured, the organ should be brought to the edge of the vessel, and the latter filled so that the outlet of the organ may be carried over its edge. Then the contents are to be carefully expressed into another vessel. In no case must the organ be made to support the weight of the contained water. 9. While full, the organ should be measured as to length, width and height, and as to its girth at one or more points. § 335. To measure the Volume of an Organ.—The following method is proposed by Dr. H. P. Bowditch (7, 149): “ Plunge the organ into a vessel already full, and measure the overflow.” Of course the full vessel must stand in a dish from which the overflow may be collected, and the ordinary anatomical tray will not answer. In some cases, therefore, the following method, though less simple, may be more easily adopted, and the result will be almost equally exact :— Attach a cord securely to some part of the organ. Place it ina vessel, and fill the latter with water. Then remove the organ by means of the cord, and the amount required to fill the vessel will represent the volume of the organ. In most cases, the space occu- pied by the cord may be disregarded. General References to the Preservation of Soft Parts.—The following are in addi- tion to the references given on p. 111:—U. S. Dispensatory, 18th ed., Art. Alcohol; Watts, A; Baley, A; Giinther, A, Appendix; Keen, 1, 2; Dwight, A, B, and /; Reeves, A; Highley, 7; Hyrtl, A; Mojsisovics, A, 26-87. CHAPTER IV. COARSE INJECTIONS. § 386. SPECIAL APPARATUS AND MATERIAL :—Acid, Acetic, No. 8, mixed with an equal volume of water—Aniline Red (Magenta)—Aniline Blue—Beeswax—Berlin Blue (see § 1449)—Carmine No. 40—Chrome Yellow—Chrome Green—Cobalt Blue—Dishes (2) of 100 ce. capacity—Magenta or Aniline Red—Mixing Dish, 400 cc. capacity—Pestle of Wood or Porcelain—Pins—Plaster of Paris, Finest Dental—Red Lead—Sponge—Syringe with assorted Canule—Thread, Linen No. 25-85, Cotton No, 20—Turpentine, Oil of— Varnish, Copal—Vermilion, American or Chinese. § 337. The object of injections is to render the blood vessels more apparent, and thus to facilitate their detection. The impor- tance of a perfect familiarity with their position and relations cannot be overestimated from the surgical and experimental standpoints. § 338. Syringe.—A syringe is usually employed to force the injecting mass into the blood vessels. It should have the following features :—(A) Ample capacity, so that one syringe full will fill the entire arterial or venous system of the animal to be injected. Of course this does not apply to large animals like horses. One of 200 cc. is adapted to cats. (B) The piston of the syringe should fit well and be leather packed (Fig. 35). (C) There should be canulz of various sizes corresponding to the different vessels to be-injected. The brass anatomical syringes (Fig. 87, 38) are best, but quite expensive. Care of the Syringe.—As soon as an injection is finished, expel any remaining plaster into the waste pail. Then fill the syringe severa] times with clean water and expel it. Force a part of a syringe full through the canula, so it may be entirely emptied. Finally, it is best to unscrew the top of the barrel and remove the piston, so that the bar- rel may be entirely emptied. Wipe the piston with an old towel and oil the leather packing before returning the piston to the barrel. If glue or wax mass is employed, the syringe should be cleaned with hot rater. If the piston becomes so loose that the mass passes it instead of being forced out through the canula, remove the piston, and make the leather packing flare slightly (Fig. 35). If the canula becomes clogged, it may be easily opened by using a small knitting needle. § 339. White-Metal Syringe (Fig. 35)—Syringes of this kind are cheap and answer very well for both coarse and fine injections. The metal canula is much too large to insert in an ordinary vessel, but that difficulty may be easily overcome by the use of glass can- ule (Fig. 36) and a rubber tube for connection (Fig. 42). 138 ANATOMICAL TECHNOLOGY. \ Barrel.—The barrel of the syringe is the large cylindrical part in which the piston fits, The injecting mass is drawn into it by pulling the piston in the direction of the handle. Fic. 35.—WHITE-METAL SYRINGE WITH Torp UNSCREWED AND PISTON REMOVED; x.3. Canula.—The canula is the smaller part which serves to connect the syringe with the object to be injected. : Handle.—The handle is a continuation of the piston. It projects from the barrel, and by it the piston is moved. Piston.—The piston of a syringe is within the barrel. Its end should be packed with leather, as shown in the figure, so that it will fit very closely. Canula or Nozzle.—The canula serves to connect the syringe with the object to be in- jected. The end should be cut off obliquely. It is then like a wedge, and may be inserted into the vessel much more easily than one cut squarely off. The caliber of the canula should be as great as can be put into the vessel to be in- jected. For plaster injections (§ 341) the Fic. 86.—CANULE; x .6. canula should not be less than 1 mm. at its narrowest point. A.—Metal canula with lateral arms at the end next the syringe, and a slight shoulder at the small end. B.—A glass canula cut off obliquely at its small end, C.—A glass tube drawn out for two canule. § 340. To prepare glass canule, take a glass tube about 6 mm. in diameter and from 8-10 cm. in length, and heat its middle evenly in a Bunsen flame. When the glass is softened, draw the two ends apart until the tube is sufficiently reduced in caliber in the middle ; then after cooling make a fine scratch with a file as shown in C, and the two may be broken apart. When separated, grind the end first on a fine file with water to make it obligue as in A and B, and finally on the fine oil stone to make it smooth. Heat the larger end in the flame to round the sharp edges. INJECTION MASSES. 139 In this figure (Fig. 87) of the regular brass anatomical! syringe, are shown four canule of various sizes and a separable stop-cock. The stop-cock fits upon the end of the short CODMAN & SHURTLEFF, BOSTON. Fie. 37,—Brass SYRINGE; x.5. canula of the syringe, and the canule for insertion in the vessels fit upon the end of the stop-cock, In most syringes of this kind the stop-cock may be dispensed with and the canule fitted directly to the syringe if desired. INJECTION MASSES. § 341. Plaster of Paris Mass.—The most convenient mass is composed of the finest plaster of Paris stained with carmine solu- tion for arteries and with Berlin blue for veins. To facilitate the KF = preparation of the mass, a quan- "t= ees @ tity of both colors should be kept tell es ee, in stock. § 842. Carmine Solution.— Thie +a prepare d by erin ding toa tee Brass SYRINGE WITH MOVABLE STOP-COCK AND CANULZE ‘paste 4-5 grams of carmine No. For Fine INJECTIONS; x.3. 40 in 20 ce. of water and then dissolving it in 50 ce. of strong ammonia. To this solution is then added 75 cc. of glycerin and 500 cc. of water. After shaking well, filter through fine flannel or absorbent cotton. § 343. Blue.—Berlin blue (§ 1449), a saturated aqueous solution, 500 cc., glycerin, 75 cc. Mix the glycerin and the blue, and filter as for red. The glycerin preserves the solutions and retards the setting of the plaster (Gage, 1, 717). § 344. Various Colors—A. ed.—Plaster mass may be well colored by American or Chinese vermilion, red lead or a solution of aniline red (magenta): Magenta, 2.5 grams; 50 per cent. alcohol, 100 ce. i40 ANATOMICAL TECHNOLOGY. B. Blue—The plaster mass may be colored blue by cobalt or uitramarine blue or a solution of aniline blue: Aniline blue, 2.5 grams ; 50 per cent. alcohol, 100 cc. C. Yellow or Green.—Employ chrome yellow or green. Permanent preparations should not be made of an animal in- jected with a mass colored by one of the aniline dyes, for they are soluble in alcohol and fade in the light. The vermilion and cobalt blue are the most permanent, but the carmine and Berlin blue last many years. § 345. Preparation of Plaster Injection Masses.—The masses should be used immediately after preparation, and before the plaster has time to set. Approximately the same volume of plaster and liquid should be employed for ordinary injections. If, however, one wishes the mass to fill the smallest vessels, the liquid should be increased so that the ratio is as 1-2 or even 1-3. A. Mass Colored with Carmine.—Measure out 100 ce. of the finest plaster of Paris and put it into a mixing dish, a tea or coffee cup, that will hold about 400 cc. Add to this plaster about 100 ce. of the carmine solution (§ 348), and mix thoroughly with a wooden or porcelain pestle. Finally, add slowly and with constant stirring the 50 per cent. acetic acid. Add the acid till the color changes to bright red and the odor of the acid in the mass is quite perceptible. An excess of acid is less injurious than a deficiency. B. Mass Colored with Berlin Blue.—Plaster same as for car- mine. Add 100 cc. of the Berlin blue solution (§ 343), and stir well. No acid is necessary. C. Masses Stained with Aniline.—Measure out 100 cc. of plas- ter and put it into the mixing dish as directed above; then add, for red, 20 cc. of the magenta solution and 100 cc. of the undiluted glycerin solution ($171). Stir thoroughly. For blue, add 50 cc. of the blue aniline solution and 75 cc. of the 15 per cent. glycerin. D. Mass Colored with Vermilion or Red Lead.—Put 25 grams of the dry color into the mixing dish and add 25 cc. of 15 per cent. glycerin. Grind the color thoroughly to crush all the lumps. Finally, add 100 cc. of plaster and 100 cc. of 15 per cent. glycerin, and mix very thoroughly. E. Masses Colored with Cobalt or Ultramarine Blue, Chrome Yellow or Green.—Employ 15 cc. of the color, and prepare as directed for the vermilion (§ 345, D). WAX AND TALLOW INJECTIONS. 141 § 346. Wax and Tallow Masses.— Wax Mass.—Beeswax, 2 parts ; Canada balsam, 2 parts; Vermilion, 2 parts. Mix the wax and Canada balsam and melt over a water bath. Then grind the vermilion thoroughly in a small amount of mastic varnish, and add it to the mixture. Heat over the water bath for half an hour or more. This mass flows very finely. Hyrtl, A, 616. Tallow Mass.—Tallow, 900 grams; Magnesia usta (calcined magnesia), 15 grams; Vermilion, 30 grams. Grind the magnesia and vermilion in a small amount of mastic varnish or turpentine, before adding to the melted tallow. Harri- son, A, II., 866. § 347. Practical Working of Wax and Tallow Injections.— First. The animal must be warmed to 38-40° C. This is best done in a large galvanized iron dish that may be covered and the water kept hot by means of a Bunsen burner or in some other way. All the heating should be done in a water bath so that no burning may occur. When the animal is warmed through (the time required de- pends on the size of the animal), the canula should be put in posi- tion (§ 358). Warm the syringe thoroughly by filling it with hot water and slowly emptying it. Warm the mass till it is quite fluid, and stir it well. If itis not heated above 50° C., it will not burn most mammalian tissues. Fill the syringe with the mass and force it out, to make sure the mass is thoroughly mixed. Then fill the syringe, connect it with the canula in the vessel, and force the -mass in rather more rapidly than directed for plaster (§ 359), but the operation should not be so long continued. One cannot inject Fishes or Amphibia with wax mass, as Hyrtl has well said, for the heat required to warm the subject and the mass would cook the tissues. For them, starch or some other cold flowing mass, or glue which remains liquid at a low temperature, must be used. After the injection is finished, the animal should remain in a cool place for at least three or four hours before the dissection is commenced. § 348. Choice of Specimen for Injection.—A young adult and lean cat is best. It should be fasting except for special purposes. § 349. Time of Injection.—Inject before the rigor mortis comes on. If that is impossible, it is better to put it into warm water (85° C.) for an hour to make the muscles flexible. This is not abso- 142 ANATOMICAL TECHNOLOGY. lutely necessary, but the smaller vessels will be more likely to be injected if the muscles are flexible. § 850. Arteries to Inject for a Complete Injection of the Ani- mal, named in order of Desirability : A. femoralis, A. carotidea, Aorta (Fig. 39, 101). yi AE Tea Fie. 39.—FEMORAL VESSELS; x.5. § 351. Veins to Inject: V. femoralis, V. jugularis externa, Postcava (Fig. 101). As to Cleanliness, see § 199. INJECTION OF THE FEMORAL VESSELS. § 352. Posture.—Place the cat dorsicumbent, as in Fig. 76. § 353. Exposure.—Grasp the meros close to the trunk with the pollex and index, and the,femur will be felt in an interval between DISSECTION. 143 the muscles on the cephalic side (upper side in the present posture). The femoral vessels are just entad of the skin and connective tissue, and parallel with the femur in the proximal third of the meros. To expose the vessels, lift a triangular flap of skin (Fig. 39). § 354. Parting the Hair.—Before making the incisions, wet the hair well with a sponge, and with a comb part it along the lines where the incisions are to be made. Incisions can be very much more neatly and easily made after the skin is thus exposed. Fic. 39.—Preparation.—The arteries were injected caudad from the aorta abdominalis (§ 101); then the veins were injected from the V. poplitea in the popliteal space, in the concavity of the knee (Fig 30). After half an hour the triangular flap of skin was dis- sected free and turned to the left and secured by a pin passing through its tip into the muscles of the left meros. All the fat and connective tissue were then removed with the tracer, fine forceps and scissors. A. (Arteria) femoralis—Femoral artery.—This is the continuation of the A. iliaca externa (§ 101). It is between the vein and nerve. Ann, abd. ext. Annulus abdominalis exterior s. ectalis—External (ectal) ingui- nal ring.—This is the ectal opening of the inguinal canal through which the chorda sper- matica passes into the abdominal cavity. C. sp. Chorda spermatica—Spermatic cord.—This is a bundle of structures passing from the testis to the abdominal cavity. It is composed mainly of the spermatic artery and vein and the vas deferens. Lg. P. Ligamentum Poupartii (Poupart’s ligament, Crural arch).—This is a liga- mentous or aponeurotic arch dorsad of which pass the femoral vessels. N. (Nervus) cruralis anterior (Anterior crural nerve).—This is the largest branch of the lumbar plexus of nerves. It is both muscular and cutaneous in distribution. Quain, A, I, 604. Scarpa’s Triangle.—This is the triangular depression on the cephalic side of the meros in which the femoral vessels are found. Quain, A, I, 454; Gray, A, 546. V. (Vena) femoralis—Femoral vein.—The femoral vein is continued by the V. iliaca communis as it passes into the abdomen. It is caudad of the artery as the two pass dorsad of the Ligamentum Poupartii, but ventrad of it in the meros. § 855. Dissection.—With the tracer and fine forceps, very care- fully dissect the artery free from the vein, nerve and connective tis- sue for about 2 cm. from the abdominal wall. Be very careful not to stretch the artery. It seems only about half the diameter of the vein. § 356. Incisions in the Vessel.—When the artery is free, put the handle of a scalpel wet in 15 per cent. glycerin entad of it (Fig. 40); with a Charriére scalpel then make a V-shaped incision that will include about one third the width of the vessel as it is flattened on the scalpel handle. Cut entirely through to the scalpel handle on which the vessel rests. The Charriére should be held pen-like (Fig. 63), and so that the apex of the V (Fig. 40) shall point periph- 144 ANATOMICAL TECHNOLOGY. erad. A more convenient, but less safe way for beginners, is to Mf f Fic. 40.—INcISIONS AND PREP- ARATION FOR LIGATURING ; x 6. employ scissors as shown in Fig. 40. It is sometimes desirable also to cut the V from apex to base as shown in Fig. 42. Enlarge the opening in the vessel by inserting the probe wet with 15 per cent. glycerin. § 357. Ligatures.—While the probe is still in the vessel, with the fine forceps grasp the middle of a thread 30-40 cm. long and push the loop through entad of the vessel, and at a point centrad of the incision (Fig. 40). The loop may then be grasped by the fingers or forceps and drawn through as far as desired. Instead of pushing the thread through as directed above, one may put the forceps entad of the vessel first and grasp the loop and pull it through. Bernard, A, 263. When the thread is through as far as desired, cut the loop. The thread nearest the incision is for tying the canula in the vessel ; the other is for ligaturing the ves- sel when the injection is finished. Both threads should be loosely tied in a szr- geon’s knot (Fig. 41), so that they may be quickly tightened. § 858. Introduction of the Canula.— When the threads are prepared, remove the probe from the vessel, select a canula of the proper size, that is, as large as can be put into the vessel, and make sure that it is open by blowing into it or forcing water through it with the syringe. Hav- ing wet its small end, put it into the ves- sel so that the injection will be centrad. To insert the canula, grasp one edge of the V-shaped incision with the fine for- ceps and pull it open. Now introduce A t Ss () XA Dy ‘y Su ry eons Knot. Sl 5 Kd Viel uu — re kinat. Ss Fie. 41.—Dousie LIgATURE, x1. the canula and push gently with a slight twisting motion. At the same time pull with an equal force in the opposite direction with the MAKING THE INJECTION. 145 fine forceps by which the edge of the incision is grasped. As soon as the canula is in the vessel, let go the edge of the slit and grasp the whole vessel where it sheaths the canula. Pinch quite firmly, and pull while the canula is pushed into the vessel for about 1 em. The canula being smooth slips into the vessel notwithstanding the pressure of the forceps. Rest the elbows on the table to steady the hands. The canula should be very smooth, and the serrations on the for- ceps must not be too deep or they will cut the vessel. The canula may be polished as directed for instruments (§ 183), and any roughness may be removed by the oil stone. As soon as the canula is properly in- serted, put the thread nearest the incision (Fig. 40) so that it will press on the canula within the vessel, and then tighten the knot. If the canula has an enlargement near the end (Fig. 36, A), it cannot escape when tied as in Fig. 42. If there is no enlargement or a glass canula is used, the thread must be tied to some part of the canula outside the vessel. If there are transverse projections (Fig. 36, A), the thread should be tied around one of them. Ifa glass canula is used, tie as shown in Fig. 42. All the threads should be knot- ted in a hard knot finally, and the ends should be cut within a centimeter of the last knot. § 359. Making the Injection.—As soon p,4 49 Insnrrixe AND as the canula is secured in the vessel, fill the — sucurine Canuna; x5. syringe partly with water or normal salt solu- tion, connect it with the canula in the vessel, and force a little of the liquid in to make sure the canula is open and properly inserted. In connecting the canula and syringe, grasp the canula with one hand and hold it firmly while making the connection. Do the same in separating them. After forcing a small amount of water into the vessel, separate the canula and syringe, expel the water, and then prepare the mass as directed above (§ 345). Stir the mass thoroughly, and then fill the syringe, being sure to lower the syringe as the mass is drawn 10 146 ANATOMICAL TECHNOLOGY. into it, so that no air may get into the syringe. Connect the syr- inge with the canula which is in the vessel (§ 358). Hold the canula firmly with one hand and pull toward the syringe as the mass is forced into the vessel. Be sure that the vessel is not looped or twisted in the least, but drawn peripherad just enough to straighten it. Force the piston down steadily and continuously ; do not allow it to stop until the injection is finished. If the canula becomes clogged, the resistance will be complete, and there will be an entire absence of the elastic feeling which comes from the distended arteries. Very often the canula may be opened by pulling the pis- ton back a little and then forcing it down quickly. One can tell only by experience when the injection is finished. The vessels are usually filled, however, when the piston returns slightly on remitting the pressure. If the injection is carried too far or the pressure is too great, the semilunar valves (Fig. 102) are liable to be ruptured and the heart filled, or some vessel may give way. § 360. Tying the Vessel.—As soon as the injection is finished, tie the vessel with the thread provided for the purpose (Fig. 42), draw back the piston slightly, and then cut the string holding the canula in the vessel and remove the canula. § 361. Cleaning the Canula, Syringe and Mixing Dish.—Do this immediately after the injection is finished before the plaster has time to set. Expel the plaster remaining in the syringe into the waste pail ; then fill the syringe with water and empty it. Do this several times, and then force some clean water through the canula. Finally, it is best to unscrew the top of the syringe and pour out any liquid that has passed the piston. Throw any plaster remaining in the mixing dish into the waste pail and clean out the dish very thoroughly. The plaster must not be thrown into the sink lest it should set and clog the waste pipe. The dissection may commence in half an hour after the injection is finished. § 362. Injection of the Femoral Vein—Fig. 39.—Dissect the vein free for 2 or 3 cm. from the abdominal wall as described for the artery (§ 353). Compress the vein and force the blood centrad. It will pass very readily and leave the vein nearly empty. Now press on the vein just as it enters the abdomen and try to force the blood peripherad. There will be seen a bulging in the vessel ex- tending about .5 cm. from the body wall. There are two valves at INJECTION OF THE VARIOUS VESSELS. 14% the peripheral end of the enlargement which prevent the flow of blood in this direction. Make a V-shaped incision in the vein cen- trad of the valves in the same manner as directed for the artery (§ 356). Compress the thorax and hold the cat upright to facilitate the flow of blood. When as much blood as possible is removed, insert the canula (Fig. 42), and inject plaster prepared as directed (§ 359). The injection should be made as directed for the arteries, but it should be remembered that the walls of the veins are thinner than those of the arteries, and hence the pressure must be more moderate. On account of the valves in the systemic veins (Fig. 102), it is necessary to inject cen- trad. The injection may be made to pass the valves sometimes, however, by manipulating the part while the mass is forced in. § 863. Injection of the Aorta Abdominalis.—Posiure and Exposure.—Place the cat dorsicumbent, and then expose the ab- dominal viscera as shown in Fig. 76, and directed hereafter. Turn the four flaps aside, and then turn the intestines to the left. The right Aidney will be seen on the right side, and in the middle line the postcava (Fig. 101). § 364. Dissection, and Insertion of Canula.—With the tracer tear away the mesentery (Fig. 80) and connective tissue in the middle line opposite the caudal margin of the right kidney. The aorta is dorsad and sinistrad of the postcava in this region, and between the two great psoas muscles. Free itfor2-8cm. Makea V-shaped incision with scissors (Fig. 40), insert and fasten the canula, and inject as directed above (§ 359). If only the cephalic part of the body is to be studied, it is necessary to inject cephalad only, but if the entire animal is to be studied, one should inje¢t first cephalad and then caudad. ‘I'he second injection should be made as soon as possible after the first. As soon as the injection is made, the postcava should be opened to allow the blood to escape. § 365. Injection of the Postcava.—The exposure is the same as for the Aorta abdominalis. Inject as directed for the V. femoralis (§ 362). § 366. Injection of the V. Jugularis Externa.— Posture.—Place the cat dorsicumbent and a block flatwise under the neck and shoulders. Rotate the head so that the nose points away from the side to be injected. Exposure.—Press upon the throat and find the larynx (Fig. 30, 148 ANATOMICAL TECHNOLOGY. § 224). Then press upon the side of the neck near the head and de- termine the position of the wing of the atlas, diapophysis atlantalis (Fig. 52, § 229). Part the hairalong a caudo-cephalic line from about midway between the wing of the atlas and the larynx, and then commencing opposite the cephalic edge of the wing of the atlas, carry an incision directly caudad for 3-5 cm. Divaricate the skin, and the external jugular vein will appear, full of blood. Injection.—Dissect the vein free as directed for the A. femoralis, make a V-shaped incision, insert the canula, and then remove as much blood as possible, as directed (§ 362). Finally, inject with blue plaster (§ 348). It is impossible to fill the small vessels with plaster on account of the valves (Fig. 102). If one wishes to inject the venous system of the cat, it may be done successfully in most cases by injecting blue gelatin into the jugular or femoral vein. See Appendix, § 1450. § 367. Injection of the Arteria Carotidea.— Posture.—tThe pos- ture should be the same as for the V. jugularis externa (§ 366). Exposure.—Make an incision through the skin as directed for the external jugular vein (§ 366). Dissect up the mesal edge of the skin to the ventrimeson. Determine the position of the larynx, and then make an incision 2-3 cm. long just laterad of the larynx and through the sterno-mastoid muscle. Divaricate the cut edges of the muscle, and there will be seen extending parallel with the trachea the carotid artery, the vagus and sympathic nerves, and the V. jugularis interna (Fig. 101). Dissection.—W ith the tracer and forceps, dissect the artery free rom the nerve and vein. Make a V-shaped incision, insert the canula, and inject centrad as dirested for the A. femoralis (§ 359). All the arteries of the body will be filled excepting those cephalad of the place of injection on the side injected. To fill those, one must inject cephalad after the general injection is made. References to Coarse Injections.—Bernard, A, 191, 262; Gage, 1,717; Harrison, A, U, 865; Heath, A, 547; Hyrtl, A, 615; Straus-Durckheim, B, I, 90; Mojsisovies, A, 15-24, CHAPTER V. OSTEOLOGY—THE STUDY OF THE BONES. THE DETERMINATION OF THE RIGHT AND LEFT WITH CERTAIN BONES—SPECIAL MNE- MONICS OF THE HUMERUS—DETALIED DESCRIPTION OF THE SCAPULA, HUMERUS, CARPALIA, CLAVICULA, STERNUM, COSTA, PELVIS, VERTEBRA AND SKULL. § 368. A general description of the whole skeleton has been given on pp. 87-95. In accordance with the general plan of this work as stated in § 128, certain parts of the skeleton are also described somewhat in detail, while others are mentioned only incidentally or not at all. Sooner or later, of course, the student will consult some complete treatise upon Human, Veterinary or Comparative Anatomy, and thus acquire the information here omitted. We believe, however, that he will do well to make for himself drawings and descriptions of the bones not fully described here; the drawings should be in outline or but slightly shaded ; the descriptions should be in two parts, general and brief, and special and detailed. DETERMINATION OF RIGHT AND LEFT. § 369. The right and left of paired bones may be determined by reference to a mounted skeleton or figure. The longer membral bones and the parts of the shoulder and pelvic girdles may also be distinguished by means of the following special formule :— In all cases, except with the scapula, innominatum and fibula, the long axis of the given bone is placed horizontally from the left to the right of the observer, and the distal end is made to point to the side to which the given bone belongs. At the end of the formula for determining the side of the body to which a long bone belongs, are placed directions for the recogni- tion of one of the extremities and two of the sides or aspects which are not opposite. The end and the sides not given may then be readily ascertained. Finally, there are directions for determining 150 ANATOMICAL TECHNOLOGY. the aspects of the limbs as wholes, together with some special mne- monics for the humerus. § 370. Clavicula—Clavicle, collar bone (Fig. 48).—A. Man.— It should be placed with the greater concavity up, the projecting part of the thick, mesal or sternal end toward the observer; then the flattened lateral end will point to the side to which the bone belongs. B. Cat.—It should be held with the subcylindrical end mesad and curving downward, the great concavity toward the observer ; the flattened end will then point to the side to which the bone be- longs. In young cats the two ends are so nearly alike that it is difficult to determine right and left. § 871. Scapula—Shoulder blade (Fig. 43-45).—The gleno-ver- tebral angle (§ 383) should be held toward the observer and the glenoid fossa down; then the mesoscapula will be on the side to which the bone belongs. § 372. Humerus—(Fig. 46).—The bone should be held with the olecranon fossa (Fig. 71) up, the epitrochlea toward the observer (the musculo-spiral groove in man away from him). In the cat and many other animals, rarely in man also, there is a foramen (/’m. epitrochleare, Fig. 46), near the caudal border of the distal end (§ 417). The olecranon fossa, the deepest of the distal fossa (Fig. 71) is on the dorsal aspect. The Foramen epitrochleare in the cat and the most prominent apophysis (epétrochlea) of the distal end are on the caudal side in both cat and man. § 373. Radius—(Fig. 30).—The bicipital tuberosity should be held down, the styloid process on the side away from the observer. The styloid process is the most distal part of the bone. It is on the cephalic side, while the bicipital tuberosity, which is near the prox- imal end, is mostly on the ventralside. The distal end is the larger. § 374. Ulna—(Fig. 30).—The great sigmoid cavity should be held down, the lesser sigmoid cavity from the observer; then the smaller end points to the side. The great sigmoid cavity is on the ventral aspect at the proximal end; the lesser one is on the cephalic aspect just distad of the greater one and continuous with it. § 375. Innominatum—Pelvic bone (Fig. 30, 51).—It should be held with the ischiatic tuberosity toward the observer, the pubic DETERMINATION OF RIGHT AND LEFT. 151 arthral facet down, the cotyloid fossa looking to one side; the fossa will be on the side to which the bone belongs. § 376. Femur—(Fig. 30).—The bone should be placed with the head pointing away from the observer, the intercondylar fossa or notch down. The nearly spherical arthral head is situated at the proximal extremity ; it faces approximately cephalad. The longitudinal con- cavity of the whole bone and the intercondylar fossa or notch are on the ventral aspect. § 377. Tibia—(Fig. 30)—It should be held with the tuberosity for the patellar ligament up, the malleolus facing away from the ob- server; the end bearing the malleolus will point to the side to which the bone belongs. The most distal part (malleolus) is on the cephalic, and the lon- gitudinal concavity on the ventral aspect. § 378. Fibula—(Fig. 30).—If the bone be placed horizontally, with its distal extremity toward the observer, and the distal arthral surface up, then the deep rough depression at the latero-distal mar- gin of the arthral surface will be on the side to which the bone be- longs ; or, in grasping this end with the pollex and index, the pollex of the side to which the bone belongs may be easily put into this depression. This method, so far as we know, was first devised by G. 8. Shep- pard, a student in the anatomical laboratory of Cornell University. The distal arthral surface is on the cephalic aspect, and the depression for the ligament spoken of below is at the ventro-distal edge of this surface. The arthral surface of the distal extremity is on the side, while that of the proximal extremity is nearly on the end. The depres- sion spoken of at the distal end is for the attachment of the ‘‘ pos- terior fasciculus of the external lateral ligament’’ of the ankle. § 379. Determination of the Right and Left with the Entire Limbs.—The sides of the whole arm may be recognized by remem- bering that the capitellum, radius and pollex (thumb) are on the cephalic side, while the olecranon process and fossa are on the dorsal side, and the convexity of the elbow points dorsad. The sides of the whole leg may be determined, since the tibia and primus (great toe) are on the cephalic aspect, and the convexity of the knee faces dorsad. (§ 80, 219). 152 ANATOMICAL TECHNOLOGY. § 380. Special Mnemonics of the Humerus.—With a bone having such numerous and important anatomical relations, so vari- ously placed in different animals and in the same animal at differ- ent times, so frequently involved in surgery, and so generally rep- resented in painting and statuary, it is very desirable that the names and relative positions of the parts should be promptly remembered. The following mnemonic suggestions may prove useful to some :— Of the two ends of the bone, proximal and distal, the former is the larger and has the longer name. The cephalic side is also called radial, and both these names are longer than the corresponding words caudal and ulnar, which apply to the opposite side. With one exception, the principal features of the cephalic side have longer names than the similar parts upon the caudal side. Trochiter, capitellum and Fs. radialis are longer than trochin, trochlea and Fs. ulnaris. The trochiter itself also is larger than the trochin. Epicondylus equals epitrochlea in length, but the latter is read- ily associated with ¢roch/ea, and itself suggests the name of the #’m. epitrochleare. In the normal position of the arm, the deep olecranon fossa (Fig. 71) is uppermost with both man and cat. With the cat also, the longer and more decided dorsal concavity of the bone as a whole may be, though somewhat remotely, associated with the back of a saddle horse. § 381. The selected portions of the skeleton are here described in the following order, which is mainly that of their simplicity :— Scapula, humerus, ulna, radius, carpus, clavicula, sternum, coste (ribs), pelvis, vertebree, and skull. The other membral bones and the Os hyoides have been briefly described in $$ 220-224. THE SCAPULA (Fig. 80, 43, 44, 45, 67, 74, 75). References.—Straus-Durckheim, A, I, 507-509; Parker, A, 215, Pl. xxx.; Owen, A, II, 488; Gray, A, 218-223; Quain, A, I, 81; Chauveau, A, 81; Chauveau (Fleming), A, 72; Flower, A, 221 and 229 ; Humphrey, A, 363-870 ; Mivart, B, 89-91 ; Leyh, A, 170, 171. § 382. General Description —The scapula (shoulder blade or blade bone) is a flat irregular bone imbedded in the muscles on the lateral aspect of the cephalic region of the thorax (Fig. 30, 67, 74, 75), and articulating with the humerus to form the shoulder joint. As seen from its ental or ectal aspect (Fig. 43 and 44), the out- THE MARGINS AND ANGLES OF THE SCAPULA. 153 line of the scapula may be characterized as either subtriangular or approximately semicircular. The former term is more commonly employed, perhaps because it is more applicable to the human scapula. But if the two scapule of the cat are placed with their straighter sides in apposition, they will be seen to cover an area which is approximately circular, although the borders are more or less undulating. § 388. The Margins and Angles of the Scapula.—lit is at least convenient to regard the scapula as triangular, and as presenting therefore three sides (margines) and three angles (anguli). The thicker (glenoid or arthral) angle articulates with the hu- merus, and presents several elevations and depressions which will be described separately. Its larger part is occupied by a concave surface, the fossa glenoidea, for articulation with the humerus; hence that border of the bone which is separated from the fossa only by its lip is called the Margo glenoideus. Between the fossa and the other border springs a hook-shaped projection, the Pre. cora- coideus, and the border is thence named Mrg. coracoideus. The intermediate border is called the Mrg. vertebralis from its proxim- ity to the Colwmna vertebralis. Of the borders, the glenoid is the longest and straightest. The coracoid is the shortest and least regular, and its outline varies in different individuals. According to the observations of Parker (A, 215, Pl. xxx., Fig. 1-3), in the cat and in some other Carnivora this margin ossifies from an independent center and remains for some time separate from the rest of the bone. The vertebral border is intermediate in length, and presents a nearly regular curvature. With young individuals this margin is cartilaginous, representing a suprascapula, but later it becomes codssified with the rest. The angles, respectively more and less obtuse, formed by the junction of the vertebral margin with the other two, are called coraco- vertebral and gleno-vertebral. The emargination of the coracoid border near the neck of the bone (at the lower end of the dotted space in Fig. 43) is known as the Incisura coraco-scapularis (Flower, A, 223). In the human scapula it is deeper and commonly called the suprascapular notch. § 884. Description of Fig. 43.—The ental aspect of an adult left scapula. Acromion.—This is more distinctly seen in Fig. 44 and 45. § 885. Aree Musculares—Areas of the attachment of muscles.—Upon these two fig- ures of the scapula and upon four views of the humerus (Fig. 68-71), the areas of muscular 154 ANATOMICAL TECHNOLOGY. attachment are enclosed by interrupted lines. Following the method of Gray (A) and H. 8. Williams (1), the origins are indicated by dots and the insertions by short lines. It is easy to associate these two marks with the letters o and i, which form respectively the initials of origin and insertion. The scapula affords origin to the following 10 muscles : Subscapularis, supraspinatus, infraspinatus, meditriceps, spino-deitoideus, acromio-deltoideus, teres (major), micostulis (teres minor), biceps and evra- [is ---~. coideus. Upon it are inserted ort Sat dp *s, the following 7 muscles: 0 yet rho © SKS, ‘ Acromio-trapezius, spino-tra- wor 4 aca q pezins, rhomboideus, serratus, FO ea aa i: SO ES levator angult scapula, levator clavicule and occipito-scapu- laris. On the figure the in- sertion area of the last named muscle is represented as too = near the coraco-vertebral an- ; % gle. . \ Qe 8 886. Collum — Neck. — ‘\ 2 This is. the thickened and * slightly constricted portion of ; the scapula connecting the - gilenoid end or angle with the “ body of the bone, According to Quain (A, II, 88), its limits are differently assigned by anatomists and surgeons. § 387. Foramen Nutriens— cide ior gue” The vascular f Th prot? Lene midi to e vascular foramen.—There 3.4 puert may be 1, 2 or 8 of these fora- T mina upon the ental aspect, Fia, 48.—THE EnTaL ASPECT OF AN ADULT LEFT and their location is quite ScaPuLa ; x1, variable. They always enter obliquely so as to point toward the glenoid end of the bone, and at least one of them is traceable to the base of the mesoscapula. Fossa Glenoidea.—See description of Fig. 45, § 399. § 388. Fossa Subscapularis.—This name is applied to the entire ental surface of the bone ; as shown upon the figure, however, the muscle of the same name does not arise from the whole area. Most of the margin of the fossa is more or less raised. The shaded area represents a shallow longitudinal furrow which coincides nearly with the mesoscap- ula (Fig. 44). Between the furrow and the coracoid margin are two well marked ridges for the attach- ment of tendinous intersections of the If subscapularis ; there are usually other ridgcs which are most distinct in old individuals. Near the glenoid margin is a prominent ridge which separates the Fs. subseapularis proper from the shallow furrow which gives origin to the M. teres. The M. micostalis arises from the middle two fifths of the M7g. glenvi- deus, and its glenoid third gives origin to the M. meditriceps. Metacromion.—This is better shown in Fig. 44 and 45. § 889. Processus Coracoideus—The coracoid process.—This, as better seen in Fig. 45, THE ECTAL ASPECT OF THE SCAPULA. 155 projects sharply entad between the Fs. glenoidea and the Mrg. coracoideus. From its extremity arises the MW. cvracotdeus (Fig. 75). Ridges.—See F3. subscapularis. Tuberculum Bicipitale—See Fig. 45. § 390. Description of Fig. 44.—The ectal aspect of the scapula. The principal feature of this surface is the sub- triangular Jamina which projects therefrom; its direction is approximately longitudinal, but it is more nearly parallel with the longer part of the coracoid border, and it inclines in the opposite direction. It begins as a triangular elevation at the vertebral border of the scapula, and rises rapidly to about the mid- dle of the length of the bone, where its edge is thickened and roughened. From this point toward yy the glenoid end its eleva- Clonaid i Loe ey tion remains nearly uni- COLE UIE Lee Cas" form, but there are pro- Fyq. 44.—Tue EcraL ASPECT OF AN ADULT LEFT ScAP- jections which will be wba; x1. described presently. This ectal ridge is the mesoscapula or spine of the scapula. § 391. In the light of Embryology and Comparative Anatomy, the entire scapula may be regarded as essentially a subcylindrical bar. With most Mammals the sides are pro- duced in three directions so that a transection is irregularly T-shaped ; the upright of the T represents the ectal ridge just described, and the two arms of the cross-piece represent the two lamine at right angles therewith which constitute the principal part of the bone, and whose borders are respectively glenoid and coracoid. By Parker (A, 215), these three regions are called respectively mesvscapula, postscapula and prescapula. Consistently with these names, the glenoid border should be called Mrg. postscapularis, and the coracoid Mrg. prescapularis ; the fosse between them and the mesoscapula should also be similarly designated. Since, however, the anthropotomical name for mesoscapula is spine, and in the natural attitude of man its direction is approximately horizontal, these fosse have been named iufraspinous and supraspinous, while the muscles arising there- from are called infraspinatus and supraspinatus. Until it shall be agreed to change the names of these muscles, it will probably be more convenient to retain the anthropotomical names for the fosse. § 892. Acromion—Pre. acromialis—Acromion process (Fig. 30, 48, 46, 47)—This forms the free extremity of the mesoscapula. Its ectal border is deflected slightly from the line of the mesoscapula toward the coracoid border. In man it articulates with the clavicle, but in the cat it is connected therewith by only a slender ligament or strip of fascia. 156 ANATOMICAL THECHNOLOGY. § 393. Delta Mesoscapule—The delta of the mesoscapula (Fig. 44).—We suggest this as a suitable designation of the slightly elevated triangular rough surface at the vertebral end of the mesoscapula. § 394. Fossa Infraspinata—The infraspinous fossa.—This is the larger of the two ectal fosse, and is distinctly triangular in shape. metacromion. It is overhung by the mesoscapula and § 395. Fossa Supraspinata—The supraspinous fossa.—This is less regular in form than the infraspinous fossa, and its areais less extensive; buat the muscle which occupies it is larger than might be inferred, both on account of the inclination of the mesuscapula and its own projection beyond the coracoid border of the scapula. Mesoscapula—Spine of the scapula.—sSee above (§ 390). § 396. Metacromion—(Fig. 48, 67).—At its greatest elevation, near the glenoid end, the mesoscapula is produced over the infraspinous fossa as a quadrate or subtriangular pro- cess, the metacromion. Its ectal surface and free border are rough for the insertion of the A. Glenoid end of right scapula. Theol. bicipitale fossa : trachitercana--- 9 Trochin S a °. “eo, . , as be a “e,* . eye B. Head of right humerus, Fie. 45.—Tur GLENcID END oF AN ADULT Riewr Scapuna (A), AND THE PROXIMAL END OF AN ADULT RicHT HUMERUs (B); slightly reduced. MM. levator clavicule and acromio- trapezius. § 397. Tuberositas (Mesoscapule)— The tuberosity of the spine of the scapula.—At about midway between the tip of the acromion and the delta the mesoscapula is thickened and roughened, constituting the tuberosity. § 398. Explanation of Fig. 45, A.—This shows the glenoid end of a right scapula. The bone is so placed that the acromion appears less pointed than the metacromion, the infraspi- nous surface of the mesoscapula is much foreshortened, and only a part of the glenoid border is shown; the coracoid border is not represented at all. Between the acromion and the ectal margin of the F%. glenoidea is a deep notch, the Incisura magna (scapularis), or “ great scapular notch.” § 399. Fossa Glenoidea—This is seen to be a shallow concavity with a pear-shaped outline. The smaller end forms a distinct Tocl. (tuberculum) bi- cipitale for the attachment of the biceps at the root of the Pre. (processus) coracoideus. Near this end, the ental border of the fossa presents a slight emargination. § 400. Pre. (processus) Coracoideus—The coracoid process.—This shows here to the best advantage as a hook-like process comparable with the beak of some birds (whence its name), or with a half-bent finger, as suggested by Humpbrey (A, 866). At its base, oppo- site the emargination near the smaller end of the Fs. glenoidea, is a nutrient foramen. § 401. Explanation of Fig. 45, B.—This represents the proximal end of a right humerus, with the dorsal side uppermost. When, therefore, the humerus and the scap- ula are in contact at the shoulder, the upper and narrower part of the arthral surface of the former is received by the lower and wider part of the Fossa glenoidea. THE HUMERUS. 157 The general outline of the proximal end of the bone is approximately that of an irreg- ular lozenge, the two smaller angles blunted, and one of the sides strongly indented. The angles are dorsal and ventral, caudal and cephalic, while the sides face obliquely ventro- cephalad, etc. The following descriptions should be considered in connection with what is said of the parts under Fig. 46 :— § 402. Canalis Bicipitatis—The bicipital canal or groove (Fig. 30, 46, 69, 70, 75).—This appears as a notch between the trvchin and the trochiter, and is overhung more by the former. Through it passes the tendon of the Jf biceps on its way to the Tbcl. bicipitale of the scapula (Fig. 45, A). § 403. Caput Articulare—The arthral head or anatomical head of the humerus (Fig. 30, 46, 68-71).—This presents a smooth convex surface which, as viewed perpendicularly to the proximal end of the bone, is irregularly circular in outline. Really, however, it extends upon the dorsal aspect of the bone, and is, as a whole, approximately triangular. It is much larger than the F%. glenoidea of the scapula with which it articulates, being twice as long and more than half as wide again. § 404. Fossa Trochiterianu—The trochiterian fossa (Fig. 80, 68).—This is a depression upon the cephalic aspect of the proximal extremity of the humerus near the tip of the trochiter. Upon it is inserted the W. infraspinatus. § 405. Trochin—The caudal, “inner ” or “‘ lesser” tuberosity (Fig. 3, 46, 69-73).—This forms the caudal obtuse angle of the lozenge represented by the entire proximal aspect. Notwithstanding the objections of Hyrtl (B, 200), we have employed the names epicen- dylus, epitrochlea, trochiter and trochin, which were proposed by Chaussier and adopted by Straus-Durckheim (A, I, 512). § 406. Trochiter—The cephalic, “outer” or ‘‘ greater” tuberosity (Fig. 30, 46, 68, 69, 71, 67, 74).—The proximal border of this forms the ventro-cephalic side of the lozenge rep- resented by the entire proximal end of the bone. THE HUMERUS (Fig. 6, 7, 30, 45, 46, 67-75, 105). References.—Straus-Durckheim, A, I, 511-514; Owen, A, II, 511; Humphrey, A, 371-377 ; Chauveau, A, 83, 84; Chauveau (Fleming), A, 73, 74; Flower, A, 239, 246 ; Leyh, A; Gray, A, 2238-228 ; Quain, A, I, 85-87. § 407. General Description.—This is the single bone of the brachium, the proximal segment of the arm. According to the membral terminology suggested by Marsh (see § 83), it is the ce- phalic O. propodiale. Its proximal and distal ends form with the scapula and with the ulna and radius the shoulder and elbow joints respectively. In all Vertebrates excepting the “fishes,” that is, in all Am- phibia, Reptiles, Birds and Mammals, excepting the armless Amphibia (Cecilians) and Reptiles (serpents and a few lizards), the humerus is present and gives attachment to numerous and impor- tant muscles. In the cat, as partly shown upon Fig. 68-71, it affords origin and insertion to many muscles. 158 ANATOMICAL TECHNOLOGY. The humerus of the cat presents a subcylindrical shaft—the diaphysis, and two enlarged and irregular ends—the Hatremitates proximales and distales. Viewed from the ventral or dorsal aspect, the caudal and ce- Troohiter: sExtremitag ‘proxtmalias Extremctas diatalcg, Fosse radcalis* t Fossa, ul marig Capitatium; Trocktea. Fic. 46—Tur VENTRAL (ANTERIOR) ASPECT OF AN ADULT RigutT HumERvs; x1. phalic outlines of the entire bone are concave, the con- cavity being both greater and more regular on the cau- dal side (on which the three braces are placed). Seen,’ however, from either the cau- dal or cephalic side, as in Fig. 68 and 70, the dorsal and ventral outlines are S-shaped. On the dorsal side the sharper curvature is near the distal end, while the reverse is the case with the ventral side. In other words, the proximal extrem- ity is more enlarged dorsad, and the distal one ven- trad. The cat’s humerus does not present the appearance of having been ¢eisted which characterizes that of man and some other Mammals— an appearance which is due, at least in part, to the devel- opment of ridges with inter- vening furrows having a more or less distinctly spiral arrangement for the attachment or accommodation of muscles, vessels or nerves. § 408. Description of Fig. 46.—This represents the ventral aspect of the right humerus, that which is most commonly and fully examined and compared. The same aspect of the left humerus is represented in Fig. 69, and the cephalic, caudal and dorsal aspects in Fig. 68,70 and 71 respectively. § 409. Canalis Bicipitalis—The bicipital canal or groove (Fig. 380, 45, 46, 69, 70).— This is a marked depression upon the ventro-caudal aspect of the proximal extremity. As better shown in Fig. 45, it lies between the eminences called trochiter and trechin. In the THE HUMERUS. 159 fresh state it is converted into a foramen or closed canal by tendons which are inserted upon these parts. Through it plays the tendon of the MW. biceps, the one which represents the “long” or “ glenoid” head of the muscle in man. By Straus-Durckheim (A. I, 512), the canal is called “‘ coulisse bicvpitale.” § 410. Capitellum (humert)—The radial head, external or outer condyle (Fig. 30, 46, 6). —The distal end of the bone presents a smooth saddle-shaped surface, the caudal border of which is raised, and the cephalic border rounded. As seen from the ventral aspect, this arthral surface is nearly equally divided by a slight ridge, and the convex cephalic part is the capitellum. This surface narrows as it is continued over the distal end of the bone, so that its shape, if extended in a plane, would be approximately lanceolate or pear-shaped, with a distinct emargination at the cephalic side of the base. With the capitellum articulates the fossa at the proximal end of the radius ; this end, unfortunately, being likewise named capitellum. It would be well if anatomists could agree to call one of these parts capitellum and the other capitulum. § 411. Caput (humert) Articulare—The arthral or anatomical head of the humerus.— The smooth convex arthral] surface of this part hardly appears in this view of the bone, but is shown in Fig. 71. In man it is distinguished from the non-arthral surface of the rest of the Hat. proximalis by a furrow or constriction, the anatomical neck. In the cat, this neck is not clearly defined. . § 412. Crista Deltoidea—The deltoid ridge—‘‘ Créte deltoidienne externe,” Straus- Durckheim (A, I, 513)—(Fig. 46, 68, 69)—This is a narrow, nearly straight, and—in well marked adult humeri—sharply defined raised line extending from the tubercle for the insertion of the M. micostalis (Fig. 69) at the base of the trochiter on the cephalic aspect of the proximal extremity distad and ventrad, to lose itself on the third fourth of the ven- tral border. The sharpness which characterizes its proximal portion disappears at about the middle of the bone. 8 413. Crista Pectoralis—The pectoral ridge—“ Créte deltoidienne antérieure,” Straus- Durckbeim—(Fig. 46, 69).—This name is applied by us to the ill defined rough line upon the proximal two thirds of the ventral aspect of the humerus. This and the Crs. deltotdea converge distad, but cease to be distinct before meeting. The long triangular interval between them is called by Straus-Durckheim (A, I., 513), “ empriente deltoidienne.” Mivart applies (B, 92, Fig. 53), the name deltotd ridge to what seems to correspond to this interval, and inaccurately states that the two parts of the M. deltoideus above mentioned are inserted upon it. 8 414. Diaphysis—The shaft (Fig. 46, 30, 68-71).—Although the shaft of the humerus may be generally described as approximately cylindrical, it is slightly compressed, so that at any point its cephalo-caudal diameter is less than its dorso-ventral. It is slightly curved so as to present a ventral convexity. For convenience of description, the entire bone may be said to consist of a subcylindrical shaft and enlarged extremities. Strictly speaking, however, the diaphysis includes all but the proximal and distal epiphyses, and these are less extensive than the regions desig- nated as extremitates. In a young animal the proximal epiphysis separates along an undulating line passing distad of the caput articulare and the tubercle for the insertion of the M. micostatis. The greatest length of the epiphysis equals only about one eighth of the length of the entire humerus, whereas the Zt. proximalis includes about one fifth. The distal epiphysis also includes merely so much as bears the arthral surfaces with the epi- trochlea and epicondylus, whereas the proximal limit of the at. distal’s embraces also the Fin, epitrochleare. Upon the caudal aspect of the diaphysis, near the junction of the first and second fourths, and nearer the ventral than the dorsal border, is to be seen, with adult humeri, a 160 ANATOMICAL TECHNOLOGY. narrow longitudinal depression roughened for the attachment of the conjoined tendons of the MM. teres (major) and latissimus (dorsi). It is indicated by an interrupted line on Fig. 70. On Fig. 46 it does not appear, but its proximal end would be opposite the proxi- mal end of the longer brace. Its length equals the dorso-ventral diameter cf the bone opposite its distal end. § 415. Hpicondylus—The epicondyle or external condyle (Fig, 30, 46, 68, 69, 71, 74).— This isa rough subconical eminence upon the cephalic aspect of the distal extremity. To it is attached the proximal end of the cephalic (external) lateral ligament of the elbow, and from it arise the MM. Extensor ulnaris and Ext. minimi. Obliquely proximad from the epicondylus extends the Crista epicondylaris, which loses itself on the dorsal aspect of the diaphysis nearly opposite the point of nearest approximation of the deltoid and pectoral crests upon the ventral aspect. The epicondyle has been called “outer” or “ external condyle,” and more recently by Markoe (7) and others “‘ external epicondyle.” § 416. Epitrochlea—The epitrochlea or internal condyle (Fig. 30, 46, 69, 70, 71, 75).— This is is a rough subconical eminence upon the caudal aspect of the distal extremity. It is larger than the epicondylus, and springs abruptly from the nearly plane caudal surface formed by the caudal prominence of the trochlea. Proximad, however, it is directly con- tinuous with the bar forming the caudal boundary of the Fm. epitrochleare. 8 417. Fm. (Foramen) Epitrochleare—The epitrochlear or supracondyloid foramen (Fig. 30, 46, 69, 70, 75, 105).—This is a narrow perforation from the ventral to the dorsal aspect of the humerus near the caudal side of the distal extremity. Through it pass the N. medius and the A. brachialis on their way from the dorso-caudal to the ventral aspect of the arm. In the cat, the Fm. epitrochleare is within the naturally assigned limits of the Ext. distalis, but it is wholly within the diaphysis ; its distal boundary is sometimes very near the diaphysio-epiphysial suture, and sometimes separated therefrom by a space equal to the longer diameter of the orifice. The Fm. epttrochleare exists in the other Felide and in some other Carnivora (Flower, A, 246), and occasionally—partly circumscribed by ligament—in man (Humphrey, A, 378 ; Quain, A, I, 87). Usually, however, the human humerus presents merely an emargination of the bone, along which pass the median nerve and the brachial artery. 8 418. Fossa Radialis and Fs. Ulnaris—The radial and ulnar fosse of the humerus (Fig. 46).—On the ventral (anterior) aspect of the distal extremity of the humerus, just proximad of the arthral surfaces of the trochlea and capitellum, are two slight depressions, against which, in the strongly flexed condition of the elbow, abut the coronoid process of the ulna (Fig. 30, Pre. coronoideus), and the side of the capitellum or proximal arthral end of the radius (Fig. 20); hence their respective names. Between the two fosse, especially in well marked bones, isa slight ridge. The Fossa ulnaris is described, but not named, by Straus-Durckheim (A, I., 513). § 419. The Fossa olecranalis, on the dorsal aspect of the distal extremity, will be described in connection with Fig. 71. § 420. Trochin and Trochiter—The caudal (lesser or inner) and the cephalic (greater or outer) humeral tuberosities (Fig. 30, 45, 68-71).—These parts of the proximal extremity have been described in connection with Fig. 45, and their muscular attachments will be mentioned in connection with Fig. 68-71. See also above, Canalis bicipitalis. It has been mentioned under Fig. 45 that while the trochin is wholly caudal in position, the trochiter ig about equally ventral and cephalic. Trochlea—(Fig. 46, 69, 71).—This is the half-saddle shaped arthral surface at the caudal side of the distal end of the humerus. Its caudal border is raised and sharply THE CARPALIA. 161 defined, but cephalad it is continuous with the capitellum, the limits of the two surfaces being indicated by a slight ridge. Ventrad, the two surfaces are nearly equal in extent, but dorsad the capitellum gradually narrows and disappears as seen in Fig. 71, while the trochlea continues upon the dorsal aspect of the bone and has a decidedly oblique direction. THE CARPALIA (Fig. 6, 30, 47). The bones of the carpus (wrist) have been enumerated in § 84. References.—In addition to the references given in §§ 84, 85, see Gegenbaur, B; Straus-Durckheim, A, I, 518-524; Mivart, B, 96-98; Gray, A, 235-241; Quain, A, I, 90-93, 99; Chauveau, A, 88, 89; Chauveau (Fleming), A, 78, 80; Leyh, A, 177-182; Flower, A, 252-260; Humphrey, A, 387-390. 8 421. Explanation of Fig. 47.—This represents the dorsal aspect of the carpus and of the contiguous parts of the metacarpalia of an Asiatic lion seven months old, and of two young dogs. The let- tering is nearly uniform in the three figures, but the present description refers only to the lion. P, I, M, A, Mi, the meta- carpalia of the pollex, in- dex, medius, annularis and minimus; p, the O. pisi- forme, which is really a sesa- moid bone in the tendon of the M. flexor uinaris, and not a true carpal element ; u, m, td and tm, the unci- Fie. 47.—THE Dorsal ASPECT OF THE CARPAL REGION forme, magnum, trapezoid oF A Youne LION (LARGEST FIGURE) AND OF TWO and trapezium respectively, Youna Does. (From Wilder, 19, 301, Fig. 1.) forming the distal row of carpalia ; as stated in § 84, the unciforme is supposed to represent two elements of the typical or primitive carpus. The proximal row consists of but two cartilaginous pieces, commonly known as the cuneiforme (py) and the scapho-lunare. Since cuneiforme has become well established in the names of three of the tarsal bones, we have, upon the suggestion of Prof. O. C. Marsh and in accordance with the custom of some European anatomists, substituted therefor the term pyramidale, which was employed by Straus-Durckheim (A, I., 520), This element represents the wlnare of the primitive carpus. The larger proximal piece is a single mass of cartilage, but a section shows that ossifi- cation has begun from three separate centers. The two larger correspond to the scaphoides (se) and the lunare (1) of man, and to the radiale and intermedium of the primitive carpus. The third and smaller center (ce) probably represents the centrale of the primitive carpus, which is not distinct in man. So far as appears from the figure of Mivart (B, Fig. 60), the carpus of the cat is essen- tially similar to that of the lion. 11 162 ANATOMICAL TECHNOLOGY. CLAVICULA (Fig. 80, 48, 66, 67, 72). The clavicle or collar bone is briefly described in § 212. References.—Straus-Durckheim, A, I, 509; Flower, A, 228; Gegenbaur (Lankester), A, 477; Gegenbaur, C ; Gray, A, 215-218; Quain, A, I, 84, 96; Parker, A, 215; Hum- phrey, A, 859-363. § 492. Explanation of Fig. 48.—This represents the unusually large and well marked clavicles or collar bones of an old male cat. Their mesal or sternal ends are apposed, and are seen to be approximately cylindrical. The left is placed in nearly its natural attitude in the body, showing that its cephalo- : pe y caudal diameter is nearly uniform, and that laterai ae ‘Lateral each end curves slightly caudad, the mesal end the more decidedly. The right is so placed as to show the caudal aspect, and display the dorsal concay- ity. The mesal half is nearly straight, but the lateral is quite regularly curved. The dorso-ventral diameter of the bone increases gradually toward the lateral end, which is about twice the width of the mesal. Directly or indirectly, the clavicle affords attachment to the Mm. clavo-trapezius, clavo- mastoideus and clavo-deltoideus, but as it is connected with the sternum and the scapula only by ligaments, it is moved with the muscles instead of forming an efficient fulcrum for their action. is mesal Sinister Cap. Fie. 48.—TaHr RicHT AND LEFT CLA- VICULH OF AN OLD CaT; x1, THE STERNUM (Fig. 7, 30, 50, 72, 73, 99, 100). The sternum or breast bone was briefly described in § 210. References.—Straus-Durckheim, A, I, 496, 497; Mivart, B, 49, 50; Flower, A, 73: Humphrey, A, 821-829 ; Gray, A, 207-210; Quain, A, I, 25-27; Chauveau, A, 75; Chau- veau (Fleming), A, 66; Leyh, A, 164-166 ; Parker, A, 215. § 423. Explanation of Fig. 49.—The ventral aspect of an adult sternum, with the contiguous parts of the costicartilagines. Incomplete views of the sternum are given in Fig. 30, 50, 72, 73, 99 and 100. The sternum consists of a mesal series of osseous or partly cartilaginous segments called sternebre, united by cartilages. The figure was drawn from a dried sternum, and the intersternebral cartilages are not shown distinctly, neither is indicated the line of junc- tion of the osseous and cartilaginous portions of the caudal segment. Of the sternebre, the most cephalic and the most caudal have received special names, presternum and viphisternum. The intervening segments constitute the mesosternum. § 424. Mesosternwm.—As indicated in § 210, there may be either 6 or 7 mesosternebre, making the total number of sternebre 8 or 9. The variation is due to the presence or absence of a short and nearly cubical piece between the xiphisternum and the sixth con- stant mesosterneber. This piece is neither figured nor described by Mivart (B, Fig. 24), or Parker (A, Pl. xxx, Fig. 8), and does not appear distinctly in the figures of Straus- Durckheim (A, Pl. vi, Fig. 2, and Pl. vii, Fig. 2), notwithstanding his intimation (A, I, 546) that it is always present. In the sterna examined by us this seventh piece is sometimes quite large, and in other cases so small as to be unrecognizable, at least from the surface. We have also observed considerable diversity as to the number of costicartilagines which reach the sternum, but are not yet prepared to say whether 8 or 9 isthe more frequent THE STERNUM. 163 number. The costicartilages which reach the sternum articulate therewith diarthrodially, but there is considerable diversity as to the extent of the synovial capsules. Each of the constant mesosternebre is two or three times as long a3 wide, and slightly enlarged at the ends so as to be somewhat of a prdeste rm dumb-bell shape. 3 § 425. Presternum.—tThis is sometimes called manubrium from rt its form in man. It is nearly twice as long as the average mesoster- neber, and the cephalic half, which is cartilage in the kitten, is com- pressed and tapers to a blunt point. On each side is an oblique shoulder for the attachment of the first costicartilage, so that the entire presternum is shaped somewhat like the head of a lance. Its ventral aspect is prominent on the meson, forming the presternal keel. $ 426. Xiphisternum.—This is also called the ziphoid or ensiform cartilage. In the adult cat only the caudal third or fourth is cartilage, and its tip is enlarged into a disk. The rest of the xiphisternum tapers caudad from its base. The sternum affords attachment to the MM. ectopectoralis, entopec- toralis, sterno-mastoideus, sterno-hyoideus and some others. § 427. Relation of the Sternebre to the Costicartilagines.—While dissecting, it is often desirable to designate the number of a sterneber when the sternum is so covered by muscles as to make the enumera- tion difficult. In these cases the ribs or their cartilages may usually be counted from the most cephalic of the series, their relations to the sternebre being as follows :— With the six constant mesosternebre, the cartilages are attached at the cephalic end, so that the third mesosterneber, for example, which is the fourth sterneber, would be the segment just caudad of the point of attachment of the fourth cartilage. The first cartilages are connected with the sides of the presternum, which is really the first sterneber; the relations of the eighth and ninth cartilages are less definite and constant. mesosternum. COST (RIBS) AND COSTICARTILAGINES (COSTAL CARTI- LAGES). Fig. 30. References.—Straus-Durckheim, A, I, 492, and IJ, 57; Quain, A, I, 27, 141; Gray, A, 210, 295 ; Flower, A, 85 ; Chauveau (Fleming), A, 67, 140 ; Chauveau, A ; Leyh, A, 162, 209 ; Humphrey, A, 329-337 ; Mivart, B, 50-52. Fia. 49.— THE VEN- e ASPEC § 428. The coste or ribs—13, rarely 14, on each ye eae side—constitute a series of arched, highly elastic wom; x1. bones which, with their continuations, the costicar- tilagines, the sternum and the thoracic vertebra, form the conical skeleton or framework of the thorax (Fig. 30 and 50). The ribs and their cartilages are slender and subcylindrical in form. They present, in expiration and moderate inspiration, a com- pound curve, the convexities being caudal and lateral (Fig. 30 and 164 ANATOMICAL TECHNOLOGY. 50). The ribs proper have each a general caudal inclination from the tuberculum to the arthron costicartilaginis, while the carti- lage has a cephalic inclination from the arthron to the sternal end (Fig. 30). In full inspiration the ventral or sternal ends of the ribs are nearly ventrad of tie vertebral ends, the caudal convexity being partly or entirely obliterated (Fig. 50). § 429. Special Characters.—The capitellum of the 12th and 13th ribs—14th if present—articulates with but a single vertebra. The capitellum of the first articulates to a slight extent with the body of the last cervical, but the diarthrodial part of the articula- tion is entirely confined to the body of the first thoracic (Flower, A, 23). The first rib and those last named above (12, 13, 14), pos- sess no ligamentum interarticulare (Fig. 50). The 12th and 13th ribs—14th if present—possess no arthral tuberculum ; it is also sometimes absent from the 11th. The tuber- culum of each of the others articulates diarthrodially with the diapophysis of the corresponding thoracic vertebra; thus, the tuberculum of the first articulates with the diapophysis of the first vertebra, and that of the seventh with the diapophysis of the seventh, etc. : § 430. Sternal, Asternal and Floating Ribs.—The cartilages of the first nine ribs (Fig. 49)—rarely of only the first eight—are articu- lated with the sternum, and hence are called sternal ortrueribs. The remaining three (or four) are called asternal or fatse ribs, as their cartilages do not reach the sternum. Finally the 13th—14th if pres- ent—is not attached to the one just cephalad of it by connective tissue, as are the 10th, 11th and 12th, but ends independently in the abdominal muscles, and hence is called a floating or vertebral rib. (Humphrey, A, 329, 337; Hutchinson, A, 1016. § 431. Methods of Demonstration.—The form and the various parts of the ribs are best made out in those that have been com- pletely deprived of their soft parts as directed above (§ 248). The relations and mobility of the ribs singly and collectively, and their arthra and ligaments, must be studied on fresh or alcoholic speci- mens. § 4382. Elasticity and Mobility.—Take as lean a cat as possi- ble, place it dorsicumbent, and, commencing at the ventrimeson, remove the skin and muscles covering the sternum, and the ribs with their cartilages of one side. Press upon the thorax, and the elasticity of the ribs will be felt. Grasp the second mesosterneber COST# AND COSTICARTILAGINES. 165 and pull ventro-cephalad. This will show the way in which the capacity of the thorax is increased. § 433. Arthra—Joints.—Remove the muscles covering the tu- berculum and cervix of the seventh rib for example, and the diga- ments will be seen as white bands holding the tuberculum to the diapophysis and the capitellum in the socket formed by the demi- facets of the two vertebree (Fig. 52, Arthron capitelli). Cut away the ligaments on the caudal side of the tuberculum with the arthrotome and bend the rib cephalad. This will expose the smooth arthral surface of this diarthrodial joint. That of the capitellum may be demonstrated in the same way. To demonstrate the amphiarthrodial joints at the arthron costi- cartilaginis, the finger or some solid substance should be placed entad of the arthron, and then the ectal surface of the bone and car- tilage should be sliced away with the arthrotome. The cartilage and bone will be found continuous, the ends not being separate and smooth for gliding upon each other as with the capitellum and tuberculum. The end of the rib is but very slightly hollowed out to receive the cartilage, thus differing from the condition in man, where the cartilage is implanted in a deep pit. The diarthrodial joints of all the sternal ribs (8 or 9) at the junc- tion of the costal cartilages and sternum (§§ 424, 430), may be dem- onstrated by slicing off the ectal surface of the conjoined sternum and cartilage as directed for the Arthron costicartilaginis. § 434. Ligamentum interarticulare—lInterarticular ligament (Fig. 50).—This is most satisfactorily demonstrated in one of the middle ribs, the seventh for example. The muscles should be re- moved as for demonstrating the tubercular and capitellar joints, and the ligaments binding the tuberculum to the diapophysis should be cut. Nip away the neural arch (Fig. 53) and remove the short segment of exposed myelon. This will expose the floor of the neu- ral canal. Dissect the dorsal (posterior) common ligament from the intervertebral fibro-cartilage, move the rib, and the ligamentum interarticulare will be seen, as a rope in a pulley, passing across the floor of the neural canal in a groove on the dorsal surface of the intervertebral fibro-cartilage, and connecting the heads of the pair of ribs (§ 444). § 485. This ligament differs so remarkably from its homologue in man that a brief com- parison is added :— In man the ligament is plate-like. In the cat it is thick and band-like. In man if 166 ANATOMICAL TECHNOLOGY. completely divides the arthral surface of the capitellum into two parts corresponding to the demifacets of the two vertebra (Fig. 52, Arthron capitelli). In the cat it but partially divides the surface. In man the ligament joins the intervertebral fibro-cartilage, and does not extend from side to side. In the cat it passes from side to side in a synovial groove lined by an extension of the synovial membrane lining the joints of the capitella of the pair of ribs. Hence, while in man there are four separate Synovial cavities for the capitella of each pair of ribs possessing the interarticular ligament, in the cut there is but one, since the arthra of the capitella communicate with each other through the groove for the Liga- mentum interarticulare. References.—Bichat, A, I, 231; Mayer, 47, 273; Chauveau, A, 140; Leyh, A, 210; Cleland, 4 and 5; Quain, A, I, 141; Gray, A, 296; Gage, 5, 421. § 436. Preparation.—Fig. 50 represents two coste and costi- cartilagines separated from the body and in the position assumed during the fullest possible inspiration—that is, drawn ventrad, laterad and cepha- lad so as to obliterate their caudal convexity (Fig. 30), and give the greatest capa- city to the thorax. The cleaning process was carried only sufficiently far to re- move the soft parts, leaving the interarticular ligament and the connections of the costal cartilages and _ ster- num (§§ 252, 427). § 487. Arthron costicartilagi- ¥ mnis.—The* amphiarthrodial articuia- wrremmnnwmn Arthron costicartilaginis -— tion between the sternal end of the diaphysis and its cartilage (§ 438). § 438. Arthron mesosternebri — Costo-sternal articulation. — The diarthrodial articulation of the costal cartilage with the mesosternum. The : first costal cartilage articulates with a Fie. 50.—CauDaL View or THE SEvenTH Parr Single sterneber (presternum), the or Costs (Rigs); x1. other eight with two (§ 480, Fig. 49). § 489. Capitellum—Head.—The vertebral end of the rib ends in a somewhat pear-shaped capitellum or head which articu- lates diarthrodially with the demifacets of two contiguous vertebre (Fig. 52, Arthron capitellt.) § 440. Cervix—Neck.—The cervix or neck of the tib is the somewhat constricted part immediately following the capitellum and between it and the tuberculum. se ‘on mesosternebri. PELVIS. 167 § 441. Costa—Rib.—The costa or rib proper is the bony part of the arch extend- ing from the capitellum to the Arthron costicartilaginis, It has two extremities— vertebral or dorsal and sternal or ventral ; two surfaces—ectal and ental: two edges— cephalic and caudal. The vertebral end bears the capitellum: the ectal surface is next the skin ; the cephalic edge faces toward the head. § 442. Costicartilago—Costal cartilage—The cartilaginous continuation of the rib which passes from the sternal end of the diaphysis toward the sternum (§ 428, Fig. 49). In the figure it is deeply shaded and is between the Arthron costicartilaginis and the meso- sterneber. : § 443. Diaphysis (Cost2)—Shaft.—The diaphysis of the rib is the part between the tuberculum and the Arthron costicartilaginis. § 444. Ligamentum interarticulare, az.—Interarticular ligament.—This is a strong, smooth, band-like ligament connecting, through the floor of the neural canal, the heads of opposite ribs (2d to 11th pairs inclusive) ; (§ 434). § 445. Mesosternebra, az.—The square area between the sternal ends of the costal cartilages represents the caudal end of the 5th mesosterneber (§ 424, Fig. 49). § 446. Tuberculum—Tubercle.—The tuberculum is an elevation on the ectal surface of the rib just at the end of the cervix. It bears a smooth arthral facet which articulates (diarthrodially) with the diapophysis of the 7th thoracic vertebra (Fig. 52 and § 433). PELVIS. General References to the Pelvis.—Straus-Durckheim, A, I, 499, and II, 63; Quain, A, I, 100, 122, 159 ; Gray, A, 245; Chauveau (Fleming), A, 91,161 ; Chauveau, A, 75, 152; Leyh, A, 166, 212; Flower, A, 281 and 33; Humphrey, A, 438 ; Joulin, 1 ; Mivart, 8 and 19; Wilder,10. A chronological bibliography is given at the end of the last. § 447. Preparation.—The soft parts were fully removed by one of the processes already described (8§ 244-256). Parts of the first and second sacral vertebree were removed with nippers to expose the Arthron ilio-sacrale. To show the lines of junction between the ilium, ischium, Os pubis and Os cotyloideum, it is necessary to prepare the pelvis of a cat retaining its milk teeth. § 448. Arthron ilio-sacrale—Tlio-sacral articulation.—This is the articulation between the sacrum and the ilium. Im the figure the arthral surface on the ilium is brought into view by the re- moval of part of the sacrum. The caudal third of this surface is diarthrodial, the cephalic two thirds amphiarthrodial ; the motion, however, is very limited. The lateral masses of only the first sacral vertebra articulate directly with the ilium. § 449. Crista ilii—Iliac crest.—The iliac crest is the prominent dorso-cephalic projection of the ilium (Fig. 30, 51, § 230). § 450. Fm. (Foramen) obturatorium—Obturator or thyroid foramen.—The large oblong space bounded by the os pubis and the ischium. 168 ANATOMICAL TECHNOLOGY. § 451. Fossa cotyloidea—Cotyloid fossa, Acetabulum.—The cotyloid fossa is a deep cup-shaped cavity in the lateral aspect of the innominate bone which articulates diarthrodially with the head of the femur. The third of the circumference of the cavity next the obturator foramen is absent, thus producing the cotyloid notch. A rough depression extends from this notch about half way across the floor of the fossa. § 452. Tlium.—This is the ce- phalic part of the os innomina- tum. It articulates with the sacrum and forms a considerable part of the cotyloid fossa. § 453. Ischium—The dorso- caudal part of the pelvic bone. It forms a large part of the coty- loid fossa and about one third of the pubic symphysis. § 454. Os cotyloideum—Co- tyloid bone.—A small bone form- ing the ventral part of the floor of the cotyloid fossa. Straus- Durckheim, A, I, 502; Milne- Edwards, A, X, 358. It has not been detected in man, and can be seen as a separate bone only in immature cats. § 455. Os innominatum—In- nominate or pelvic bone.—The os Fie. ee ViEw ee Car's innominatum is made up of the Dole ae Dens, ium, the ischium, the os pubis <1. and the os cotyloidewm. These four bones are completely united in adult life. The right and left pelvic bones together form the pelvic girdle. § 456. Os pubis—Pubic bone.—It is the cephalo-ventral of the bones forming the pelvic girdle. It forms only a small part of the cotyloid fossa and about two thirds of the symphysis pubis. § 457. Pelvis, az.—‘‘ The two innominate bones, together with COLUMNA VERTEBRALIS. 169 the sacrum, form the pelvis, a complete circle of bone, or rather a short tube.’’—-Flower, A, 284. Pre, trans., Processus transversus.— Transverse process or diapophysis of the 7th lumbar vertebra. § 458. Sacrum, az.—‘‘The portion of the vertebral column to which the pelvic girdle is attached.”’ It is composed of three ver- tebree, which in adult life are more or less completely consolidated. In an immature cat which would show well the lines of demar- cation between the bones forming the Os innominatum, the sacral vertebre would be but partly codssified. § 459. Symphysis pubis, az.—This is the linear articulation (amphiarthrodial) between the ventral aspects of the two innomi- nate bones. Its cephalic three fourths is formed by the Os pubis and the caudal fourth by the ischium. In fully adult animals the symphysis usually becomes anchylosed. Vert. (Vertebra) lumbalis.—The last or 7th lumbar vertebra (Fig. 55). Vertebre caudales, az.—Tail vertebree.—These follow imme- diately after the sacrum (Fig. 30). § 460. In addition to the parts named above, the following should be mentioned :— A. The Ilio-pectineal Line and EHminence.—Neither are shown in Straus-Durckheim’s figure, from which this was copied. Both should show on the right side, however. The line extends from the ilio-sacral articulation to the most prominent part of the pubis. Opposite the cephalic edge of the acetabulum the line presents an eminence which is at or very near the junction of the ilium and pubis. B. The Tuberosity of the Ischium.—This is the most prominent thickened part of the ischium. It forms the extreme dorso-caudal part of the whole pelvis. It is upon this part the cat rests when sitting on her haunches. COLUMNA VERTEBRALIS. References.—Straus-Durckheim, A, 458; Quain, A,I, 9, 25 ; Gray, A, 182; Hum- phrey, A, 113; Milne-Edwards, A, X, 825; Leyh, A, 153; Chauveau, A, 19; Owen, A, II, 488 ; Owen, 231, Cuvier, A, I, 170; Flower, A, 10; Mivart, 3 and 24; Maclise, A, 622; Cleland, 7 and 13; Wilder, 10. § 461. The Columna vertebralis, spine, vertebral or spinal col- umn, consists of a series of osseous segments called vertebre arranged in close connection with each other and forming the bony axis of the body. It is nearer the dorsal than the ventral aspect in the cat and in most other Vertebrates. Its position and curves are shown in Fig. 30. It is prolonged caudad beyond the trunk to form the 170 ANATOMICAL TECHNOLOGY. axial support of the tail; and cephalad it is articulated diarthro- dially with the occipital region of the skull. ‘‘The different verte- bre, with some exceptions (§ 458), remain through life distinct from each other, though closely connected by means of fibrous struc- tures which permit a certain but limited amount of motion between them.”’ § 462. “Although the vertebre of different regions present great diversities of form, there is a certain general resemblance among them showing a common plan of structure. This plan is, however, worked out variously in different regions by change of form and the suppression or superaddition of parts, thus fitting them to fulfill their special purpose.’”’—F lower, A, 10. In general, each vertebra is composed of a solid subcylindrical centrum or body, and a bony arch (neural arch), with various processes, extending dorsad therefrom (Fig. 52-55). § 463. Regions of the Vertebral Column.—For convenience of description, the whole vertebral column has been divided into five regions, named in order from the head :—Cervical (7) ; Thoracic or Dorsal (18); Lumbar (7) ; Sacral (3) ; Caudal or Tail (22), (Fig. 30). The middle Cervical, Thoracic and Lumbar vertebrze are shown in Fig. 53-55, where the special characters of these three groups are well illustrated. § 464. Distinguishing the Five Groups of Vertebre and the Ends of the First Four Groups.—The cervical vertebre, except the 7th, are distinguished by the presence in the diapophysis of the vertebrarterial foramen (§ 473). ; The 7th cervical is distinguished from the thoracics by the ab- sence from its prominent diapophysis of an Arthron tuberculi, and by the absence of an Arthron capitelli from the cephalic end of the centrum (Fig. 52). It differs from the other groups by its short wide centrum, large neural foramen and slender neural spine. The thoracic vertebree differ from all the others by the presence of an Arthron capitelli on the cephalic end of the centrum or upon both ends. The Zwmbar vertebre may be distinguished by their long sub- cylindrical centra, and by the cephalic inclination of the neura- pophyses and of all the diapophyses except the first. The sacrat vertebree are more or less completely anchylosed. The caudal vertebre differ from the others by the smallness or CERVICAL VERTEBR. 171 absence of the neural foramen, the caudal inclination of the dia- pophyses when present, and by the presence in some (2d to 9th) of the so-called chevron bones. § 465. The chevron bones are small ossicles attached to the cephalo-ventral part of the caudal vertebre and forming an open cr closed arch through which passes the caudal con- tinuation of the A. sacra media. The ends of the vertebrae may be distinguished very readily by remembering that the arthral surface of the prezygapophysis (Fig. 53), situated at the cephalic end of the verte- bra, faces either dorsad or dorso-mesad, while that of the posteygapophysis faces ventrad or ventro-laterad. It follows from this that the postzygapophyses overlie the praezyga- pophyses like the tiles on a roof. Especially in the thoracic and lumbar regions, the Jnei- sura vertebralis or intervertebral notch is much deeper on the caudal than on the cephalic side. The above characters apply also to man. § 466. Demonstration.—All of the general as well as special points relating to the vertebral column may be demonstrated on a flexible natural skeleton (§ 252) and one entirely divested of its soft parts. The relation of the myelon and other soft parts must of course be demonstrated on a fresh or alcoholic specimen. § 467. Preparation—(Fig. 52).—The cleaning (§ 252), was carried sufficiently far to divest this part of the vertebral column of all its soft parts except the intervertebral fibro- cartilages. § 468. Arthron capitelli—Capitellar articulation.— This is the diarthrodial arthral cav- ity formed in two adjacent thoracic vertebre for the reception of the capitellum or head of the rib (Fig. 50).. The part of the articulation in each vertebra is called a demifacet. The 12th and 13th vertebrae have each a complete capitellar arthral surface. The caudal part of the last cervical vertebra supports part of the capitellum of the first rib; Flower, A, 23. § 469. Arthron tuberculii—This is the diarthrodial facet on the diapophysis for articulation with the rib corresponding in number to the vertebra from which the dia- pophysis arises (Fig. 50, 52). It is not present in tle last two thoracic vertebre. § 470. Atlas.—The atlas is the first cervical vertebra, and thus the first of the entire series. It articulates diarthrodially with the occipital condyles (Fig. 57). The broad lat- eral masses are the diapophyses or transverse processes, and are sometimes called “ wings of the atlas.” 8 471. Axis.—This is the second of the cervical vertebre. It articulates diarthrodi- ally with the atlas, but with the third vertebra by the interposition of jibro-cartilage, that is, amphiarthrodially, like the remaining vertebre, except the sacrum (§ 458). Its neural spine is a long sharp ridge (Fig. 30). Cerv.—Vertebre cervicales, cervical vertebre 1-7. § 472. Fibro-cartilago intervertebralis, az.—Intervertebral fibro-cartilage.—Between each of the centra, except the first and second and, the parts of the sacrum, is this very dense, tough and elastic fibrous material. ‘‘The elasticity provides for the vertebra always returning to their normal relation to each other and the column generally when they have been disturbed therefrom by muscular action.”—Flower, A, 12. § 473. Foramen vert., Fm. vertebrarteriale.—This is the canal through the bases 172 ANATOMICAL TECHNOLOGY. of the diapophyses of all but the last (rarely of the last) cervical vertebre. Through it pass the verte bral artery and vein. § 474. Foramen atlantale—Atlantal foramen.— This isa passage through the cephalic edge of the atlas just dorsad of the occipito-atlantal arthron. It transmits the first or suboccipital nerve and the vertebral artery ; Straus-Durckheim, A, I, 470. It is present in man only as an exception; Quain, A, I, 12. § 475. Lamella ventralis—Ventral or inferior lamella.—This is the thin plate-like projection ex- tending ventrad from the diapopbyses of some of the cervical vertebrae. It is most marked in the 6th. Flower, A, 22, 23. § 476. Pre. (Processus) odontoideus, az.—Odon- toid process.—This is a tooth-like projection from the cephalic part of the centrum of the axis. It articu- lates diarthrodially with the atlas, and serves as a pivot on which the atlas and head rotate. It is kept from encroaching upon the neural canal by a strong ligament. 8 477. Explanation of Fig. 53-55.—Anapophy- sis—Accessory tubercle.—This is a slender process extending laterad from the caudal part of the neural arch. It is ventrad of the postzygapophysis, and with it clasps the prezygapophysis of the following verte- bra. Itis present in the first six lumbar vertebra, and markedly in the 9th to the 13th thoracics, where, in man, it is called the inferior tubercle; Quain, A, I. 14, 8 478, Arcus neuralis, az—Neural arch.—This is a bony arch projecting from the dorsal aspect of the centrum, It is called neural arch because it over- arches and encloses the myelon or neural axis. § 479. Canalis neuralis, az.—Neural canal.—The ‘Atthron. . neural canal is formed by the neural foramina, each tubercult. foramen being a short segment of the canal. It is Fie. 52.—VENTRAL ASPECT OF enclosed by the neural arches and by ligaments, and THE CERVICAL AND OF TWO contains the myelon. ee ‘ (nore § 480. Centrum, az.—Body.—The vertebral cen- = : trum is the solid subcylindrical ventral portion of the vertebra. Contiguous vertebral centra articulate amphiarthrodially by means of an interposed disk of fibro-cartilage. Jor exceptions, see § 458. § 481. Diapophysis—Transverse process.—The diapophysis is the lateral projection of the vertebra. Its base, in the cervical vertebree (Fig. 52), except the 7th, contains the vertebrarterial foramen (§ 478). § 482. Fm. (Foramen) neurale, az.—Vertebral ring or foramen.—This is the space VERTEBRA. 173 enclosed by the neural arch and the dorsal aspect of the centrum. The neural foramina of all the vertebre, together with the ligaments, form the neural canal. § 483. Fm. (Foramen) vertebrarteriale.—This foramen is found in the base of the diapophyses of all the cervical vertebre except the last, and rarely in that. In man it is usually present in the last; Humphrey, A, 142. This foramen transmits the Arteria et Vena vertebralis (Fig. 104). 8 484. Inc. (Incisura) vertebralis—Notch—The pedicles are notched, especially on the caudal side. When the vertebre are united these notches form the so-called intervertebral foramina, through which pass the vessels and nerves to and from the neural canal. § 485. Lm. (Lamina) neuralis—Lamina.—The two laminz form the roof of the neural arch. Laterally they join the pedicles, and from their junction at the meson springs the neural spine. § 486. Metapophysis—Mammillary process.—This is a dorso-lateral projection of the prezygapophyses of the lumbar vertebre. It corresponds to the internal tubercle of the tho- racic transverse processes ; Quain, A, I, 15. Fie. 58.—CaAuDAL VIEW § 487. Pedicle.—The pedicle of a vertebra forms the oF THE FOURTH CER- side of the neural arch. It extends dorsad and joins the | vicAL VERTEBRA; x1. lamina. § 488. Prezygapophysis—Superior articulating process—This process articulates boy, neratis Hie en ty Eo poppe Fig. 54.—CaupsAL VIEW OF THE SEVENTH Fig. 55.—CaupaL VIEW OF THE FOURTH THORACIC VERTEBRA; x1. LUMBAR VERTEBRA; x1. diarthrodially with the postzygapophysis of the preceding vertebra, The arthral surface of this process faces nearly dorsad or dorso-mesad. § 489. Postzygapophysis—Inferior articulating process.—The postzygapophysis ar- ticulates diarthrodially with the prezygapophysis of the vertebra immediately following it. Its arthral surface faces nearly ventrad or ventro-laterad. § 490. Sp. neu.—Spina neuralis—Neural spine, Spinous process, az.—This is a mesal process arising from the neural arch and extending approximately dorsad. THE SKULL. General References to the Skull.—Straus-Durckheim, A, I, 380; Quain, A, I, 31; Gray, A, 149; Humphrey, A, 175; Darling and Ranney, A, 17; Cuvier, A, II, 177; Owen, 174 ANATOMICAL TECHNOLOGY. A, IT, 492; Flower, A, 94; Huxley, B, 245; Morrell, A; Milne-Edwards, A, X, 306; Gegenbaur, A, 463; Leyh, A, 122; Chauveau, A, 37; Chauveau (Fleming), A, 33; Parker and Bettany, A; Parker, 25; Turner, 4, 848-9 ; Huxley, 3, 288; Wyman, 76: Cuvier, B, Vi. § 491. “ The skull (Fig. 56-62) is the term commonly applied to the portion of the axial [somatic] skeleton situated within the head.”’ It is a strong bony case or frame enclosing the brain and affording support and protection to the organs of sight, smell, taste and hearing. It consists of several irregular bones, most of which are immova- bly united by sutures (synarthroses), so that their relative position, and hence the form of the skull, are constant. In addition to the skull proper, there are articulated to its base the mandible (Fig. 62) and the hyoid apparatus (Fig. 30, § 224). § 492. Cranium and Face.—For convenience, anatomists have divided the skull into these two regions. The cranium is the caudal part of the skull; it encloses and protects the brain. The face is the cephalic part ; it surrounds the mouth and nasal passages, and, with the cranium, completes the cavities for the eyes. Quain, A, I, 31, 74; Flower, A, 94, 102. The number of separable bones entering into the formation of the skull varies with the age of the animal. The teeth are not included. The bones given in the following tables and figures may be easily demonstrated on the skull of a cat with milk teeth. § 493. Sutures.—The sutures or lines of union between the various bones of the skull have not all received special names, but all may be properly named by forming a compound term of the names of the two bones united, as; Sutura parieto-frontalis in- stead of S. coronalis ; 8. maxillo-premazillaris, etc. Quain, A, I, 56, 58, 181. § 494. Bones of the Skull. Modified from the Tables of Quain, A, 74, and Flower, A, 104. (Fig. 56-62.) In the following Tables of the bones, the names in parenthesis beneath a given name are synonyms ; and the names behind the small or secondary braces are the anthropo- tomical equivalents of those in black letter behind the large braces. The word Os (bone), or its equivalent O., is to be understood before all the technical names of the bones excepting Vomer and Mandibula. BONES OF THE SKULL. 175 CRANIUM. BASIOCCIPITALE..... ee OF THE OCCIPITAL CAUDAL PART OF THE BODY OF THE BASISPHENOIDEUM. SPHENOID BONE, INCLUDING THE SELLA TURCICA. MESAL (5)... PRESPHENOIDEUM. j Careatie San on ane BODY OF THE (Single or Azy- a gous Bones). SUPRAOCCIPITALE. . j a PART OF THE OCCIPITAL DORSO-CEPHALIC ANGLE OF THE TABU- INTERPARIETALE. . | LAR PORTION OF THE OCCIPITAL. { BXOCCIPITALE eee PERIOTICUM........ (Petro-mastoideum. Petrosum or Petrosale). TYMPANICUM...... SQUAMOSUM........ (Squamo-Zygomati- cum). LATERAL (10). 4 pagiprarn....... (Paired Bones). ALISPHENOIDEUM.. PTERYGOIDEUM.. a7 DEUM... . FRONTIS........ sate oa ETHMO-TURBINALE FACE. waeee MESAL (2) (Single or Azygous Bones), ! | “ ; “| f J MESETHMOIDEUM... | VOMER. ...cs00-cse- CONDYLAR PORTION OF THE OCCIPI- TAL BONE. THE PETROUS AND MASTOID POR- TIONS OF THE TEMPORAL BONE ; THE FIRST INCLUDING THE LABYRINTH AND MEATUS AUDI- TORIUS INTERNUS. THE TYMPANIC RING AND AUDITORY PROCESS. THE AUDITORY BULLA AND THE POSTGLENOID PART OF THE TEMPORAL BONE. THE SQUAMOUS PART OF THE TEM- PORAL BONE WITH THE ZYGO- MATIC PROCESS, INCLUDING THE ARTHRAL SURFACE FOR THE MANDIBLE. THE PARIETAL BONE, GREAT WINGS OF THE SPHENOID BONE WITH THE LATERAL (EX- TERNAL) PTERYGOID PLATES. THE MESAL (INTERNAL) PTERYGOID PLATES. | THE LESSER WINGS OF THE SPHE- NOID BONE, saa FRONTAL BONE. THE LATERAL MASSES WITH THE DORSAL AND VENTRAL TURBI- NATED BONES OF THE ETHMOID, THE CRIBRIFORM PLATE, AND THE OS PLANUM OR ORBITAL PLATE OF THE ETHMOID THE VERTICAL (MESAL) PLATE OF THE ETHMOID BONE, INCLUDING THE CARTILAGINOUS NASAL SEPTUM. THE VOMER, OR OS VOMERIS. , 1%6 ANATOMICAL TECHNOLOGY. x THE TWO RAMI UNITE TO FORM THE [ Ramus MANDIBULA- | LOWER JAW OR MANDIBLE OR TRUS: ceiaatnatoseungeae WAST: TNEERIOR PALATINUM.......... THE PALATE BONE. THE SUPERIOR MAXILLARY OR UP- MAXILLARE.......... PER JAW BONE EXCEPTING THE INCISOR PART, LATERAL (8). MAXILLO-TURBINALE THE INFERIOR TURBINATED BONE. (Paired Bones). MALARE.... ........- THE MALAR BONE. INTERMAXILLARY, THE INCISOR PRHMAXILLARE...... PART OF THE SUPERIOR MAXIL- LARY BONE. LACHRYMALE.... .... THE LACHRYMAL BONE, l NASALE,............... THE NASAL BONE. § 495. Articulations of the Bones of the Skull. (Fig. 54-60). The following list represents the bones approximately as given in standard works on Human Anatomy. They are readily distinguishable in a nearly adult cat. The parts forming a compound bone are given in parenthesis immediately below the name of the bone under consideration. See Os occipitale. The Arabic number in parenthesis, after a bone and just before the brace, indicates the number of bones with which it articulates. The parts of a compound bone are numbered as one. See Os parietale. In giving the articulations of the mesal bones, the Arabic numeral 2 is placed in paren- thesis after all the lateral bones with which it articulates, to indicate that it is connected with both. See Vomer. If but one of the parts of a compound bone articulates with a given bone, the name of that part is given instead of the name of the whole bone; but if more than one compound enters into the articulation, the name of the whole bone is given, and that is followed by a brace and the names of the components. See Os parietale. CRANIUM. ( CAUDAD.........66 ag bs Be eis ATLAS. OS OCCIPITALE (6). (Basioccipitale, Exoccipitale, PARIETALE (2). Supraoccipitale, with the CEPHALAD....... pasatenne TEMPORALE (2). Interparietale). BASISPHENOIDEUM. BASIOCCIPITALE. CAUDAD aquenworew oss | te eo TEMPORALE (2). PARIETALE (2). DORSAD..........0005- Fronts (2). OS SPHENOIDEUM (13).. ETHMoIDEUM (2). (Basisphenoideum, ( PALATINUM (2). Alisphenoideum, FRONTIS (2). Pterygoideum, CEPHALAD........... ETHMOIDEUM (2). Presphenoideum, MESETHMOIDEUM. Orbito-sphenoideum),. VoMER. ARTICULATIONS OF THE SKULL. 177 ( CAUDAD.... OCcCTPrTaLE. DORSAD.... PaARIETALE. RAMUS MANDIBULARIS. VENTRAD.. | formes BASIOCCIPITALE. OS TEMPORALE (6).. 4 musap..... SpHenorpeum, § Ali: and_ basi- (Perioticum, * ( sphenoideum, Tympanicum, Ali- and _ basi- Squamosum). pean SPHENOIDEUM. { sphenoideum. ‘| PARIETALE. L | MaLARE. Supraoccipitale, CAUDAD.... COTE TENN ie j Interparietale. SQuAMOSUM. Squamosum, OS PARIETALE (5)..0.4 canopy... Tautou... | Samemoeum ALISPHENOIDEUM. MESAD...... PARIETALE (the platetrope). | CEPHALAD. _ FRonTIS. PARIETALE, CAUDAD,...... { ALISPHENOIDEUM. ORBITO-SPHENOIDEUM. PALATINUM. VENTRAD..... PLANUM. OS FRONTIS (8)........-5 2 | LACHRYMALE, Os FRONTIS (the platetrope). MESAD........ j ee ETHMOIDEUM. CEPHALAD.... + MAXILLARE, L NASALE. ( FRONTIS. CAUDAD..... j PRZSPHENOIDEUM. FRONTIS. DORSAD...... | eee j PRHSPHENOIDEUM. os ETHMOIDEUM (9). eed VENTRAD... | sea aaa (Ethmo-turbinal, lamina cribrosa). mai MuseTHMorDEUM. vtt++* 7 EPHMOIDEUM (the platetrope). FRONTIS. LATERAD... { MAXILLARE. L PALATINUM. FACE. CAUDAD...... PRESPHENOIDEUM. FRONTIs (2). OS MESETHMOIDEUM ().. | DoRSAD...... { KROXms.2) VENTRAD.... VoMER. LATERAD..... ETIMO-TURBINALE (2). 12 178 ANATOMICAL TECHNOLOGY. { CAUDAD........... PR2SPHENOIDEUM. MESETHMOIDEUM. DOHS AD iahicncives | eta eera nnn eh VOMER (TO)... cseceveceeens PALATINUM (2). VENTRAD......... MAXILLARE (2). PRAIMAXILLARE (2), LATERAD......... | PALATINUM (2). RAMUS MANDIBULA- ea a nae SQuaMosuUM. RIS (3 iwsinnsveteces eens MESAD........... RM. MNDBL. (the platetrope). Preesphenoideum. f CAUDAD.... j SPHENOIDEUM. j Pterygoideum. i PRASPHENOIDEUM, FRONTIS. DORSAD.... ETHMO-TURBINALE, VOMER. OS PALATINUM (7)... PaLatinum (the platetrope). MESAD.... ETHMO-TURBINALE, ee PRASPHENOIDEUM. VOMER. LATERAD... MAXILLARE. LACHRYMALE. CEPHALAD. ; Wee FRONTIS. LACHRYMALE, CAUDAD. ... PALATINUM, MALARE. MAXILLARE (the platetrope). VOMER. OS MAXILLARE........... Nee MESAD...... PRMAXILLARE. ETHMO-TURBINALE. MAXILLO-TURBINALE, PALATINUM, CEPHALAD.. Pra&MAxXILLARE. | CAUDAD..... LACHRYMALE. OS MAXILLO-TURBINALE (4). DORSAD..... ETHMO-TURBINALE, | Larmran... ea ( MAXILLARE, OS PRAMAXILLARE (3)...... heaeaae 1 Vomnr, MESAD...... Px. (the platetrope). CAUDAD............ { TEMPORALE... ks OS MALARE (3)... MESO-CEPHALAD.. LAcHRYMALE. CEPHALAD......... { Maxmane... j Processus 1 malaris. DORSAL ASPECT OF THE SKULL. 1%9 ( / PLANUM. CAUDAD.......... pa ae MAXILLARE, DORSAD.......... { . OS LACHRYMALE (5)..... 4 les ALARE. LATERAD......... { ey MAXILLO-TURBINALE, | CEPHALAD....... | ee ( CAUDAD......... FRONTIS. ETHMO-TURBINAL. VENTRAD...... { OS NASALE (6)........ eee Aap EVM OLDIE: MESAD......... NASALE (the platetrope). : MAXILLARE. | LATERAD...... { oe agen All the figures of the skull are of Felis domestica. In the description of the figures, under the general heads, which are arranged alphabet- ically, the special parts are named commencing at the caudal extremity. For fuller information concerning any of the bones or foramina, refer to the Table of Bones and of Foramina, pp. 175, 190. § 496. Preparation.—The soft parts were entirely removed (§ 250, B). The roof of the left side was then removed by sawing carefully with a fine saw to the meson at a level just dorsad of the orbits and about 2 mm. dorsad of the foramen magnum. The frontal and parietal bones were then removed with nippers by sep- arating them at the coronal, the sagittal and the lambdoidal sutures. Finally, the interparietal and supraoccipital were removed by saw- ing on the meson till the first incision was reached. This exposed the frontal sinus and the ental surface of the base of the skull. § 497. Cn. Ich., Canalis lachrymalis—Lachrymal canal.—This canal passes ceph- alo-ventrad and lies between the maxilla and maxillo-turbinal. It finally opens into the nasal cavity just ventrad of the maxillary attachment of the maxillo-turbinal and nearly opposite the fang of the canine tooth. § 498. Cst. Imd., Crista lambdoidalis.—The lambdoidal crest corresponds to the superior curved line of the occipital in Human Anatomy. Flower, A, 112, 132. § 499. Cst. temp., Crista temporalis—Temporal crest.—This marks the dorsal limit of the temporal fossa and muscle. In young cats it is considerably separated from the meson, but in adults it approaches it and may be mesal from the lambdoidal crest to the coronal suture. The mesal part is then called sagittal crest ; Flower, A, 112. Fm. m., Foramen magnum, az. Fm. j.,. Foramen jugulare—s. lacerum posterius—Jugular or posterior lacerated foramen. Fm. ov., Foramen ovale. Fm. rt., Foramen rotundum. Fm, |. a., Foramen lacerum anterius—s. lacerum orbitale, s. fissura sphenoida- lis.— Anterior or orbital lacerated foramen, sphenoidal fissure. Fm. op., Foramen opticum—Optic foramen. 180 ANATOMICAL TECHNOLOGY. § 500. Fm. plt., Foramen palatinum posterius—Posterior palatine foramen.—The passage between the opening shown in this figure and Fig. 60 is known as the posterior palatine canal. Quain, A, I, 373. § 501. Fm. sphplt., Foramen spheno-palatinum—Spheno-palatine foramen.—It leads from the orbit into the nasal cavity. x» > Fic. 56.—DorsaL View OF THE SKULL; x 1.2. § 502. Fs. ap., Fossa appendicularis.—Fossa for the appendicular lobe of the cerebellum. § 503. Fs. (Fossa) temporalis—Temporal fossa.—This is the space on the side of the skull caudad of the postorbital process of the frontal. By mistake, the name in this figure is written partly in the orbit. § 504. Fossa orbitalis—Orbital fossa, orbit.—In this space the eyes are found in living animals. Unlike the orbital fossa of man, that of the cat is not separated from the semporal by a plate of bone, but opens widely into it, DORSAL ASPECT OF THE SKULL. 181 § 505. I., Infundibulum.—This is the opening from the frontal sinus to the nasal cavity. § 506. M. a. i, Meatus auditorius internus—Internal auditory meatus.—This is divided into two parts very near its mouth, as shown by the white line. The ventral part receives the auditory nerve (VIII), the dorsal part, the facial(VII). The facial in its course curves round in the dorso-lateral part of the Pars petrosa and finally emerges at the stylo- mastoid foramen. This passage through the skull from the M. a. i. to the stylo-mastoid foramen is known as the Aqueductus Fallopii. In the Pars petrosa, about 2 mm. from its mouth, there branches cephalad a small canal, the Hiatus Fallopii, which opens oppo- site the ventral end of the osseous tentorium. § 507. O. soc., Os supraoccipitale, az.—Supraoccipital bone.—This forms the caudal part of the roof of the cranial cavity. § 508. O. i. p., Os interparietale, az.—Interparietal bone.—A small bone, separate in young animals. It is cephalad of the supraoccipital and is wedged in between the caudal ends of the parietals. § 509. O. parietale—Parietal bone.—The parietal bone forms a large part of the side and roof of the cranial cavity. § 510. O. perioticum—s. petrosum.—This is a part of the temporal bone; it encloses the internal ear, and is divided into two parts, Pars petrosa and Pars mastoidea, the latter appearing on the ectal surface of the skull (Fig. 57). § 511. O. temporale—Temporal bone.—This forms part of the floor and side of the cranium, and by its zygomatic process helps to enclose the temporal fossa. § 512. O. boc., Os basioccipitale, az.—Basioccipital bone.—It forms part of the floor of the cranium. § 513. O. bsph., Os basisphenoideum, az.—It forms the caudal part of the body of the sphenoid bone, and helps to make the floor of the cranial cavity. § 514. O. alsph., Os alisphenoideum,—This is one of the greater wings of the sphe- noid and forms part of the side and floor of the cranium. § 515. O. orsph., Os orbito-sphenoideum.—This is one of the lesser wings of the sphenoid ; it forms part of the floor and side of the cranium and part of the mesal wall of the orbit. § 516. O. frontis—The frontal bone.—The frontal bone forms a large part of the roof and part of the side of the cephalic region of the cranial cavity and the mesal wall of the orbit. It also covers the caudal part of the nasal cavity. § 517. O. plt., Os palatinum—Palate bone.—This is a very complex boue, forming part of the orbit, of the roof of the mouth, and of the floor and side of the nasal cavity. § 518. O. malare—s. Os zygomaticum, os jugale—Malar, zygomatic or jugal bone.— This bone connects the malar and zygomatic processes of the maxilla and the temporale, and with them encloses laterally the orbit and the temporal fossa, and completes the Zygoma or zygomatic arch. § 519. O. pln., Os planum.—This is not a separate bone, but merely the orbital part of the ethmo-turbinal. It is often absent. § 520. O. Ich., Os lachrymale—Lachrymal bone.—It is a thin quadrilateral bone forming part of the cephalic wall of the orbit and the caudal part of the nasal cavity. § 521. O. maxillare—Maxilla, superior maxillary or upper jaw bone.—This is a com- plex bone which forms a great part of the face. Init are implanted the dorsal (upper) molar, premolar and canine teeth. § 522. O. nasale—Nasal bone.—A thin irregular bone forming part of the roof of the nasal cavity. 182 ANATOMICAL TECHNOLOGY. Fic. 57.—VENTRAL ASPECT OR BASE OF THE SKULL. (Modified from Straus-Durck- heim); x 1.75. § 523. O. pmx., Os premaxillare—Premaxillary or intermaxillary bone.—It forms the most cephalic part of the skull, and in it are implanted the dorsal (upper) incisor teeth. Pre. z., Processus zygomaticus.—Zygomatic process of the temporal bone. BASE OF THE SKULL. 183 Prc. po., Processus postorbitale.—Post orbital process of the frontal bone. § 524. S. (Sinus) frontalis—Frontal sinus—This cavity in the frontal bone is sep- arated from its platetrupe by a bony partition (Fig. 60). It communicates with the nasal cavity through the infundibulum (I.) and is lined by an extension of the nasal mucous membrane. § 525. Sutura lambdoidalis, az.—Lambdoidal or occipito-parietal suture.—This is the synarthrodial articulation between the parietal, the interparietal and the supraoccipital bones. § 626. Sutura sagittalis, az.—Sagittal suture.—The synarthrodial articulation between the right and left frontal and the parietal bones. It extends from the nasal bones to the lambdoidal suture. In Human Anatomy, the sagittal suture is confined to the articulation of the two parie- tals with cach other, the two frontals uniting so early that they are considered as a single bone. § 527. Sutura coronalis—Coronal or parieto-frontal suture.—The synarthrodial artic- ulation between the frontal and parietal bones. § 528. Fig. 57—Preparation.—The skull was thoroughly cleaned, and while still moist the following structures were removed from the right side :— (A) The tympanic bulla was removed by inserting an arthro- tome between it and the basioccipital and prying steadily, thus exposing the Pars petrosa, the Foramen lacerum jugulare and Hm. lacerum medium, the Fenestra ovalis and Fenestra rotunda. (B) The Os pterygoideum and a part of the Os palatinum were removed by the nippers to expose the row of foramina. (C) The teeth were extracted with the nippers to expose the alveoli (sockets of the teeth). a, b.—Fractures made in removing the bulla. Bulla tympanica.—Tympanic or auditory bulla (Fig. 58). § 629. Cd. oc., Condylus occipitalis—Occipital condyle—The occipital condyle is formed mostly by the exoccipital, but somewhat also by the basioccipital. It articulates diarthrodially with the atlas. Cn, eu., Canalis Eustachiana.—Eustachian canal (Fig. 58). D. m., Dens molaris.—Molar tooth. DD. pm., Dentes premolares.—Premolar teeth. D.c., Dens caninus.—Canine tooth. DD. i., Dentes incisores.—Incisor teeth. Fm. m., Foramen magnum, az. § 5380. Fm. cd., Foramen condylare—Condylar foramen.—This foramen is some- times nearly hidden either by the projection of the bulla or its unusual approach to the Fim. jugulare. § 5381. Fm. j., Foramen jugulare—s. lacerum posterius.—Jugular or posterior lacer- ated foramen. § 582. Fm. stm., Foramen stylo-mastoideum—Stylo-mastoid foramen.—This is the ectal termination of the Aqueductus Fallopii (Fig. 56, 59, M. a. i.). § 583. Fm. 1. m., Foramen lacerum medium—s, Fm. spheno-petrosum—Middle 184 ANATOMICAL TECHNOLOGY. lacerated, or spheno-petrosal foramen.—The opening of this foramen on the ectal sur- face of the skull is just within the mouth of the Eustachian canal. It perforates the lateral edge of the cephalic projection of the bulla, and may be seen on most prepared skulls by looking into the mouth of that canal. The existence of the Foramen lacerum medium in the cat is not mentioned by any of the authorities, so far as we are aware ; but the foramen so named in this figure is between the cephalic extremity of the pars petrosa and the alisphenoideum—the position occupied by the foramen lacerum medium in man, as stated by Quain, A, I, 62, and in the dog, as stated by Flower, A, 101. This foramen in the cat also transmits an artery, which has been called internal carotid in the table of foramina (§ 562). It is so called since it anas- tomoges with the cerebral vessels within the cranium, and arises from the carotid at the proper place—slightly centrad of the origin of the lingual. It passes along the carotid canal and unites with a larger vessel extending along the mesal side of the bulla. The artery is imbedded in the wall of the Eustachian tube in its passage along the Eustachian canal to the foramen. ‘ Fm. ov., Foramen ovale. Fm. rt., Foramen rotundum. § 5384. Fm. 1. a., Foramen lacerum anterius—s. fissura sphenoidalis—Anterior Jacerated foramen or sphenoidal fissure. Fm. op., Foramen opticum, transmitting the Nervus opticus. § 535. Fm. pit. p., Foramen palatinum posterius—Posterior palatine foramen— There are usually two openings of the posterior palatine canal in the roof of the mouth as shown in this figure. (See also Fig. 56.) Fm. pit. a., Foramen palatinum anterius—s. Fm. incisore.—Anterior palatine or incisor foramen. § 586. Fs. tyh., Fossa thyrohyalis.—This is the pit into which is inserted the dorsal part of the Os hyoides (§ 224). § 537. Fs. (Fossa) mandibularis—Mandibular or glenoid fossa.—This receives the mandibular condyle and articulates diarthrodially with it (Fig. 62). § 538. Ft. rt., Fenestra rotunda.—This opening connects the tympanum with the scala tympani of the cochlea. In the living body it is covered with membrane. § 589. Ft. ov., Fenestra ovalis.—This connects the tympanum with the vestibula. In living bodies it is closed by the stapes and its connecting soft structures. § 540. M. a. e., Meatus aunditorius externus—External auditory meatus.—This extends from the side of the head to the ectal surface of the Membrana tympani. § 541. Margo alveolaris—Alveolar margin or border of the jaw.—In this border of the jaw the teeth are implanted. : . supraoccipitale, az.—Supraoccipital bone. exoc., Os exoccipitale.—Exoccipital bone. . basioccipitale, az.—Basioccipital bone. . basisphenoideum, az.—Basisphenoid bone. alsph., Os alisphenoideum (Fig. 56). pt., Os pterygoideum.—Pterygoid bone. presph., Os presphenoideum, az. orsph., Os orbito-sphenoideum (Fig. 56). . frontis (Fig. 56). vm., Os vomeris.—Vomer (Fig. 59). . palatinum.—Palate bone (Fig. 56). . malare.—Malar bone (Fig. 56). O. maxillare.—Maxillary or upper jaw bone (Fig. 56). ° 29999999990 THE BULLA TYMPANICUM. 7 185 O. pmx., Os premaxillare.—Premaxillary or intermaxillary bone. § 542. Pre. par., Processus paroccipitalis—s. paramastoideus—Paramastoid or paroccipital process.—This is a curved shelf-like projection of the exoccipital which abuts against the caudal end of the bulla. Pre. pro., Processus mastoideus—s. pars mastoidea.—Mastoid portion of the peri- oticum. Pre. z., Processus zygomaticus.—Zygomatic process of the temporal bone. Prc. po., Processus postorbitale.—Postorbital process of the frontal bone. § 543. Fig. 583—Preparation.—The soft parts were removed ; then, while the skull was yet moist, the ventral face of the bulla was ground off on a fine emery-stone. It might be removed with a watch-spring saw or on an ordinary grindstone. In grinding, the pressure should be only moderate to avoid breaking the delicate septum. § 544. Bulla tympanica—The auditory or tympanic bulla.—The bulla is a hollow subspherical part of the O. tympanicum enclosing the tympanum or middle ear. — A delicate bony septum divides the cavity into two un- Fie. 58. — VENTRO - LATERAL equal parts. This septum arises from the floor, and VIEW OF THE LEFT BULLA extends dorsad, but leaves a space over the fenestra ro- AND ADJACENT Parts; x 1.5. tunda which puts the two chambers in communication. In the lateral aspect of the bulla is the external auditory meatus (M. a. e.); attached to the ectal part of this is the external ear, and to the ental part the Membrana tympani or ear drum, which completely separates the tympanum or middle ear from the exterior of the body. Flower, A, 110, and 26, 4; Huxley, B, 249 ; Straus-Durckheim, A, I, 409. Cd. oc., condylus occipitalis.—Occipital condyle. § 545. Cn. eu., Canalis Eustachiana—Eustachian canal.—This is a short bony tube leading from the tympanum to the ventral surface of the skull. Flower, A, 111. Fm. m., Foramen magnum, az. Fm. cd., Foramen condylare.—Condylar foramen. Fm. ov., Foramen ovale. Fs, mnd., Fossa mandibularis.—Mandibular or glenoid fossa (Fig. 57), Ft. rt., Fenestra rotunda (Fig. 57). Ft. ov., Fenestra ovalis. M. a. e., Meatus auditorius externus.—External auditory meatus. O. boc., Os basioccipitale, az.—Basioccipital bone. Pre. z., Processus zygomaticus.—Zygomatic process of the temporal bone. Spt. tym., Septum tympanicum.—The bony partition dividing the interior of the bulla into two unequal chambers. § 546. Fig. 59—Preparation.—The soft parts were removed (§ 250, B), and then the section was made with a watch-spring saw while the skull was still moist. The section was made about 2 mm. 186 : ANATOMICAL TECHNOLOGY. to the left of the meson to avoid injuring the mesethmoideum and other mesal parts. The remaining parts of the left half were after- ward removed with the nippers; the septa of the frontal and sphe- noidal sinuses were likewise partly removed. Sel .~ 0, vomeris es Pepel, Fie. 59.—HEMISECTION OF THE SKULL, RiautT SIDE; x 1.5. Bulla tym., Bulla tympanica.—Tympanic or auditory bulla (Fig. 58). Fm. j., Foramen jugulare—s. Fm. lacerum posterius—Jugular or posterior lacer- ated foramen. Opposite the occipital condyle and nearly caudad of the condylar foramen is an un- named opening for a vein, Fm. op., Foramen opticum.—Optic foramen. Fm. sphplt., Foramen spheno-palatinum.—Spheno-palatine foramen. Fs. ap., Fossa appendicularis (Fig. 56). § 547. Fosse of the Cranial Cavity—(A) Fossa cerebellaris, az—Cerebellar fossa.—This is the part of the cranial cavity caudad of the osseous tentorium. It contains the cerebellum and medulla (Fig. 88). (B) Fossa cerebralis, az—Cerebral fossa.—This is the part of the cavity of the skull between the tentorium caudad and the olfactory fossa cephalad. It contains the cere- brum, thalamus, part of the optic lobes and the crura (Fig. 88). (C) Fossa olfactoria—s. rhinencephalica—Olfactory or rhinencephalic fossa.—This is the smallest of the fosse. It is limited cephalad by the Lamina cribrosa and extends caudad to the dorso-ventral ridge formed by the frontal and orbito-sphenoid. It lodges the rhinencephalon or olfactory lobes (Fig. 88). M. a. i., Meatus auditorius internus.—Internal auditory meatus (Fig. 57). O. exoc., Os exoccipitale.—Exoccipital bone (Fig. 56). O. soc., Os supraoccipitale, az.—Supraoccipital bone. HEMISECTION OF THE SKULL 187 . ip., Os interparietale, az.—Interparietal bone. . boc., Os basioccipitale, az—Basioccipital bone. pro., Os perioticum.—Periotic bone (Fig. 59). bsph., Os basisphenoideum, az.—Basisphenoid bone. temporale.—Temporal bone. parietale.—Parietal bone (Fig. 56). pt., Os pterygoideum.—Pterygoid bone. alsph., Os alisphenoideum.—Alisphenoid bone, . plt., Os palatinum.—Palate bone (Fig. 57). . orsph., Os orbito-sphenoideum. . frontis.—Frontal bone (Fig. 56). § 548. O. vomeris, az—Vomer.—The vomer is a mesal bone forming part of the septum of the nasal cavities. § 549. O. mesethmoideum, az,—Vertical plate of the ethmoid.—This is a mesal bone forming most of the partition between the nasal cavities. O. Nasale.—Nasal bone. O. mxtrb., Os maxillo-turbinale—Maxillary or inferior turbinated bone.—It is a greatly plicated bone occupying the ventral p wt of the nasal cavity. § 550. O. ethtrb., Os ethmo-turbinale—Ethmo-turbinal bone.—This is also a greatly plicated bone ; it occupies the dorsal and greater half of the nasal cavity. It projects caudad into both the frontal and the sphenoidal sinuses (Fig. 60). O. pmx., Os premaxillare —Premaxillary or intermaxillary bone (Fig. 57). O. mx., Os maxillare—The upper jaw bone.—ln this figure it is not marked, but it is the deeply shaded part just caudad of the O. Prma. Pre. pcl., Processus postclinoideus, az.—Posterior clinoid process. Pre. prcl., Processus preclinoideus, az.—Preclinoid process. Sella, Sella turcica, az.—This is a space or pit formed by the two clinoid processes (Fig. 88). § 551. S. sph., Sinus sphenoidalis—Sphenoidal sinus.—This is a space in the pra- sphenoid bone. It is separated from its platetrope by a bony partition. It is lined by a continuation of the nasal mucous membrane, and communicates freely with the nasal cavity. S. frn., Sinus frontalis.—Frontal sinus (Fig. 56, 60). § 582. Tent., Tentorium.—The osseous tentorium cerebelli is a moderately thick plate of bone projecting from the parietal bones into the cranial cavity ; it separates the cerebrum from the cerebellum (Fig. 88). Each parietal bone furnishes half of the tentorium, and its halves are conjoined at the meson by a ventral continuation of the sagittal suture ; (see Fig. 88). 099909999099 § 553. Fig. 60—Preparation.—The skull was divested of its soft parts (§ 250, B). It was then sawed obliquely across its cephaliz half so as to include the optic foramina, and to fully expose the frontal sinuses. The left lateral wall of the olfactory fossa was nipped away, and likewise the lateral projections of the maxilla. Cn. Ich., Canalis lachrymalis.—Lachrymal canal (Fig. 56). Fm. (Foramen) opticum—Optic foramen.—The optic chiasma rests in the groove between the two foramina (Fig. 114). 188 ANATOMICAL TECHNOLOGY. Fm. sphplt., Foramen spheno-palatinum.—Spheno-palatine foramen. Fm. infor., Foramen infraorbitale.—Infraorbital foramen. § 554. Lm. (Lamina) cribrosa—Cribriform plate of the ethmoid.--The mesethmoid separates the bones of the two sides. The cribriform plate is the cranial part of the eth- moid, the ethmo-turbinals properly belonging to the face. O. presph., Os presphenoideum, az.— , Presphenoid bone. O. plt., Os palatinum.—Palate bone. O. Ich, Os lachrymale.— Lachrymal one (Fig. 56). : O. planum (Fig. 56). ae O. ethtrb., Os ethmo-turbinale—Eth- mo-turbinal bone.—In this figure is shown the rounded scroll-like part projecting into the frontal sinus (§ 550). O. frontis.—Frontal bone. Sinus frontalis.—Frontal sinus (Fig. 56). or, § 555. Fig. 61—Preparation.— : After the removal of the soft parts Fm. opttcum. (8 950, B), the rami were separated at the symphysis menti (Fig. 62). Fie. 60—Dorso-caupaL VIEW OF THE LAMINA CRIBROSA AND THE SINUS § 556. An. (Angulus) mandibularis— Frontauis ; x 1.5. Mandibular angle. Cd. mndb., Condylus mandibularis.— The condyle or arthral head of the mandible (Fig. 62). D. m., Dens molaris.—Molar tooth. DD. pm., Dentes premolares—Premolar teeth—The bicuspides of Anthropotomy. D. c., Dens caninus.—Canine tooth. DD. i, Dentes incisores.— Incisor teeth. Fm. m., Foramen mentale— Mental or labial foramen.—There are almost invariably two on each side in the cat. Fs. (Fossa) coronoidea—Cor- onoid fossa.—From this fossa arises mate ; a large part of the masseter muscle, Fic. 61—LatTERAL VIEW OF THE LEFT MANDIBU- Prec. cor., Processus coronoi- LAR Ramus; x1. deus.—Coronoid process. § 557. Ramus, Ramus mandibularis—Mandibular ramus.—The mandible is made up of two similar bones joined at the symphysis menti, and these rami form the frame- work of the floor of the mouth; Flower, A, 120. In Human Anatomy, the “ramus” is the so called “ascending part,” and not the entire half of the mandible as here ; Quain, A, I, 54. § 558. Fig. 62—Preparation.—All the soft parts were removed DORSAL ASPECT OF THE MANDIBLE. 189 (§ 250, B); while still moist the two rami were slightly separated at the symphysis menti, and the teeth of the right side were extracted with the nippers to show the alveoli, as in Fig. 57. da. mandi Fie. 62.—DorsaL VIEW OF THE MANDIBLE. (Modified from Straus-Durckheim), x 1.75. § 559. Alveoli.These are the cavities in which the teeth are implanted. § 560. Cd. (Condylus) mandibularis—Mandibular condyle or arthral head.—This smooth cylindrical process articulates diarthrodially with the Fossa mandibularis of the temporal (Fig. 57). D. m., Dens molaris.—Molar tooth. DD. pm., Dentes premolares.—Premolar teeth. D. c., Dens caninus.—Canine tooth ; Wilder, 75. DD. i., Dentes incisores.—Incisor teeth. Fm. di., Foramen dentale inferior.—Inferior dental foramen. Margo alveolaris—Alveolar margin.—The margin or border of the jaw in which the teeth are implanted. Prc. (Processus) coronoideus.—Coronoid process. § 561. Symphysis menti.—The symphysis is the amphiarthrodial articulation be- tween the two rami. It is indicated in the figure by a dark line just to the left of the incisor teeth. In old cats this symphysis often becomes anchylosed, but in young individ. uals considerable motion is possible between the two rami. 190 ANATOMICAL TECHNOLOGY. § 562. Table of the Foramina and Canals of the Skull, the Bones enclosing them, and the Principal Structures to which they give Passage. The foramina are enumerated, commencing at the caudal end of the skull, Fig. 56, 62. All are lateral or paired except the foramen magnum, which is mesal. BONES ENCLOSING STRUCTURES THAT TRAV- oe THE FORAMINA. | ERSE THE FORAMINA. Basi- ex- and supra-| { Myelon, N. (spinalis) accessorius Foramen magnum .......... | occipitale......... { (XI), A. basilaris. Foramen condylare......... Exoccipitale........ N. hypoglossus (XII). Basi- and ex-occipi-| ( N. vagus ( (X), N. (spinalis) acces- Foramen jugulare........... tale, tympanicum sorius (XI), N. glosso-pharyn- Foramen stylo-mastoideum.. Meatus auditorius internus. . Aqueductus Fallopii Hiatus Fallopii........... a Meatus auditorius externus.. lacerum medium Foramen (§ 533) Canalis Eustachiana........ Foramen ovale.............. Foramen rotundum.......... Foramen lacerum anterius... Foramen opticum Foramina olfactoria......... Foramen palatinum posterius Foramen spheno-palatinum. . Foramen palatinum anterius. Foramen orbitale............ Canalis lachrymalis Foramen infraorbitale....... Foramen dentale inferius.... Foramina mentalia.......... and pars petrosa. . Tympanicum, pars mastoidea....... | Pars petrosa, basi- t sphenoideunm ... Alisphenoideum, bul- ; la tympanica Pars petrosa mastoidea, tym- Pars petrosa, pars panicum. ...... Pars petrosa Tympanicum........ Alisphenoideum ... Alisphenoideum ... Ali- and orbito-sphe- noideum.......... Orbito-sphenoideum. Lamina cribrosa... Palatinum Palatinum.......... | Maxillare, premax- illare. Palatinum, maxillare Lachrymale, max- illare, mavxillo- turbinale. Mavillare........... Mandibula.......... Mandibula.......... geus (IX), Vena jugularis. N. facialis (VII). N. auditorius internus (VIID, N. facialis (VII), A. auditoria in- terna, N. facialis (VII). N. petrosalis superficialis (ec- talis), (branch of Vidian). Admits air to the membrana tympani. Arteria carotidea interna. ee Eustachiana, A. carotidea interna (§ 533). N. maxillaris inferior (8d. divi- sion of V); small meningeal artery. N. maxillaris superior (2d or middle division of V). N. oer Palen (1st division of ), N. oculomotorius (III), N. ee (VI), N. trochlearis (IV), A.carotidea externa (large branch from the rete mirabile). Ve . opticus (IT) ; a meningeal ar- with NN. olfactorii. NN. palatini, AA. palatine. NN. spheno-palatini, AA. sphe- no-palatine. N. naso-palatinus, A. nasalis, N. oculo-nasalis, A. ethmoidalis. Ductus lachrymalis. N. infraorbitalis, A.infraorbitalis, (N. dentalis inferior, A. et V. 1 __dentales inferiores. N. mentalis, A. mentalis. THE STRUCTURE OF BONE. 191 § 568. The capacity of a prepared skull may be obtained by filling it through the Fim. magnum with sand or fine shot, and then pouring the material into a graduate glass. If the material used in determining the capacity is fine enough to pass through the fora- mina, they must be plugged in some way. The weight of the brain may be obtained approximately by reckoning the cubic centi- meters of capacity as grams and adding 4 per cent. (Wyman, 76). Thus, if a cat’s skull has a capacity of 25 cc., the brain of the same cat would weigh approximately 26 grams. Wyman’s statement refers only to the human brain, but presumably the specific gravity of the cat’s brain is nearly or quite identical with that of man. § 565. Obvious Structure of Bone.—In life the surface is covered with a dense layer of connective tissue, the periosteum. Entad of this periosteum isa layer of compact bone. The intermediate part of all bones is, however, more or less loose in structure, something like a sponge, hence it is called spongy or cancellated bone. This is especially abundant toward the end of long bones and in the vertebral centra. § 566. Microscopic Structure.—A solid mass containing: A. Haversian canals, cyl- indrical channels shown as circles in cross section, as cylinders in longitudinal sections of long bones. These canals contain the blood vessels, as may be demonstrated by exam- ining a finely injected cat’s scapula (see Frey, A). They anastomose freely, and open either upon the ectal surface or within the medullary canal. ; B. Lacune and canaliculi. These are the spaces occupied by the protoplasmic bone cells or corpuscles and their prolongations. They appear in outline like irregularly fusiform connective tissue corpuscles with many fine prolongations or branches. These branches anastomose with the branches of neighboring lacune, and sometimes open into an Haversian canal. Tn transections of long bones the solid matter and lacune are seen to be arranged in more or less concentric lamelle around the Haversian canals. CHAPTER VI. MYOLOGY—THE STUDY OF THE MUSCLES. GENERAL CONSIDERATIONS—FREQUENCY OF MUSCULAR VARIATIONS—EXPLANATION OF TECHNICAL TERMS—APHORISMS FOR DISSECTORS—LIST OF INSTRUMENTS AND MATERIALS—HOW TO USE DISSECTING INSTRUMENTS—PRACTICAL SUGGESTIONS— CLIPPING THE HAIR-—CUTTING THE SKIN—REMOVAL OF THE SKIN—NAMES AND SYNONYMS OF THE MUSCLES HEREIN DESCRIBED—DESCRIPTIONS OF FORTY MUSCLES OF THE CEPHALIC REGION OF THE BODY, WITH DIRECTIONS FOR THEIR DISSEC- TION—THE STRUCTURE OF MUSCLE, General References to Myotomy.—Bernard, A, 182-206 ; Chauveau (Fleming), 184- 186; Cleland, A, 1-7; Heath (Keen), A, Appendix ; Hodges, A; Hyrtl, A, 59-67 ; Mojsis- ovics, A, 1-15 ; Straus-Durckheim, B, 180-162; Reeves, A. § 567. Muscular Homologies.—The following works and papers deal with the general and special homologies of muscles ; the first three embrace all Vertebrates and all regions of the body ; the others refer mainly to the limbs of the Mammalia: Humphrey, E, 105-188 ; Meckel, A, V, VI; Cuvier, A, I; Quain, A, I, 185; Mivart, 4 ; Macallister, 9, 2,19; Rolleston, 13; Krause, A ; Coues, 1, 36, 47 ; Wilder, 1,4, 10, 20. § 568. General Considerations.—For the reasons stated in § 204, Practical Anatomy always begins with the skeleton, including the bones and cartilages, the arthra (joints) and ligaments. Of the soft parts, the muscles are most easily prepared, examined and preserved, and they serve, together with the bones, as Jandmarks for the recognition of the vessels and nerves ; hence Myology naturally succeeds Osteology. Yet the practical study of the muscles is not without its difficulties. Upon the limbs, excepting the distal segments, the muscles are much more numerous than the bones. For example, in the arm and shoulder girdle, if we omit the manus, there are five bones, scapula, clavicle, humerus, ulna and radius. Excluding those which arise from the humerus and are inserted upon the manus, more than thirty distinct muscles are attached to these five bones. The larger bones also are readily recognized, even when covered by soft parts; but two or more muscles in the same locality may have the same general form and direction, so that their determination may involve a careful examination of their attachments. Hence, whereas most of the bones may be prepared in the same way, the general rules for dissection must be modified and supplemented with respect to each muscle, in order that it may be exposed, dissected, examined and removed to the best advantage. § 569. Just how explicit the directions should be has not, apparently, been fully determined by anatomical teachers and writers. Some “Laboratory Directions” are so MUSCULAR VARIATION. 193 meager as to be, according to our experience, of no value whatsoever. Nowhere, in zootomical works, have we found them so complete as in the “ Dissector’s Guides ” which are used in the Medical Schools. Yet even these, in our opinion, are not altogether suited to the needs of the beginner. They are not sufficiently full; all the parts in a given region are considered at once, a plan better adapted to the advanced student ; finally, too little attention is given to typographical and paragraphic details which might facili- tate the recognition of statements and reference to other parts of the work. Without assuming to have decided correctly in this matter, we have acted upon the belief that dissection is a fine art, and by no means easy to acquire; that the beginner is liable to fall into grave errors as to manipulation, fact and interpretation; and that, upon the whole, it is better for him to follow even an imperfect method than none at all. § 570. Variation —Another difficulty met with in the study of muscles is the frequency of variations and anomalies not only as to size and shape, but also as to connections, vas- cular and nervous supply, and even presence. All standard works upon Human Anatomy record the existence of such variations, and it is probable that the careful examination of any human subject would disclose one or more departures from the condition regarded as normal. Notwithstanding the intrinsic probability that any other Mammals, at least the domes- ticated species, would vary in a similar manner, most dissectors of the lower animals seem to have assumed that what is true of one individual is true of the whole species, and the myological descriptions of Straus-Durckheim (A), Chauveau (A), Coues (47), and Krause (A) rarely mention departures from rule. Yet no two anthropoid apes have been found to agree in all respects, as may appear from the published dissections of Duvernoy (100), Humphrey (10), Champneys (1), Wyman (47), Macalister (21, 41), Barnard (1), the senior author (1) and others, and Huxley has distinctly expressed (A, 410) the belief that “endless varieties will no doubt be met with by those who carry their inquiries farther” than by the dissection of single individuals of a species ; see also the remark of Galton, 1, 175, note 30. The senior author bas remarked upon the existence of individual variations among domesticated dogs (21, 308), and we may add that no one of the scores of cats dissected by us or our students has failed to present some peculiarity of muscular arrangement. The records of these variations have not as yet been put into shape for publication, and in the present descriptions it has seemed better to give, in most cases, only what seems to be the most usual structure. The student is reminded, however, that his very first dis- section may disclose some feature hitherto unobserved. § 671. Hrrors of Manipulation.—The beginner should bear in mind that nothing is more easy than to commit some error of manipulation—whether by a cut too many or a cut too few—which may greatly affect the appearance of the parts, and lead to very mis- taken conclusions. As a rule, therefore, supposed anomalies should not be published until submitted to competent criticism, or carefully checked by the dissection of other individ- uals, or still better of the other half of the same. In all cases, the student will do well to recall the advice of Cuvier to a young medical student who ventured to tell him that he had discovered something very new and remark- able ina human body. Cuvier replied : ‘‘ Go and anatomize an ¢nsect, the largest you can find ; then reconsider your observation, and if it appear to be correct, I will believe you on your word.” After making the dissection, the student confessed that he had been in error ; (Lee, A, 56). As has been suggested by the senior author (22, 307), it is doubtful whether any dis- section by beginners should be published at all, excepting upon the approval of an experi- enced anatomist, after thorough examination. 13 194 ANATOMICAL TECHNOLOGY. § 572. Errors of Interpretation —When an author denies the existence of a part the presence of which is affirmed by other writers, the discrepancy may be due to either of five causes :— 1. Its absence is the rule, and its presence in the other cases was exceptional, 2. It was absent, though normally present. 8. It was present, but accidentally overlooked. 4, It was observed but not recognized, or was mistaken for some other part. 5. It was seen, but purposely ignored. Of course the last named explanation is also the last to be entertained, but either of the other four contingencies is liable to occur with even experienced dissectors and learned anatomists. For example, the M. entopectoralis (Fig. 72), “ pectoralis minor,” is said by Straus-Durck- heim (A, II, 336), and implied by Meckel (A, VI, 249), and Mivart (B, 145), to be wanting with the cat; its existence in any Carnivora is also denied by Cuvier (A, I, 370), and A. H. Young (1,171). Owen, however, speaks (A, III, 50), of the ‘‘ pectoralis minor of the dog,” and its presence in that animal is admitted by Haughton (115) and Wood (7, 52), as it is in the cat by the senior author, who refers (20, 306) to it as found in all the Felide and Canide examined by him. The muscle considered by the writers last named to represent the “‘ pectoralis minor” of man is so large in most Carnivora that it was not recognized by the five writers first. named as the representative of that rather insignificant muscle; in the bear and skunk, however, as stated by the senior author in the paper referred to, it is again smaller than the WV. ectopectoralis. In illustration of the second case, the WZ. supinator longus (Fig. 74) is said by Meckel (A, VI, 303), and Huxley (A, 355) to be wanting with the dog. Chauveau, however, affirms (A, 290) its presence in dogs of all breeds, and it has been repeatedly observed by the senior author. Hence we may conclude, provisionally at least, that it was exception- ally absent in the individuals dissected by Meckel and Huxley. THE TECHNICAL TERMS OF MYOLOGY. § 573. Mlusculus—Muscle.—The name for a mass of muscular fibers. Such a muscle may or may not be a true muscular integer. What constitutes a muscular integer has not been determined ; as stated in the senior author's brief discussion of the subject (10, 68), the phrase “ morphological integer” seems to have been first used with reference to the muscles by Coues (7, 223), but the gen- eral question is discussed, directly or indirectly, by Owen, Parker, Spencer, and more recently, Humphrey (E). In the present work, it has seemed best to us to recognize as separate muscles, or as distinct divisions of muscles, all the muscular masses whose origins and insertions are fairly constant and capable of definite description. In applying separate names to the divisions of the human trapezius (Fig. 66, § 607), and deltoideus (Fig. 66, § 674), and yet treating the long and short heads of the coracoideus. (Fig. 75, § 668), as a single muscle, we are certainly open to the charge of inconsistency. In the present transitional state of opinion respecting muscular integers, entire consis- tency is hardly to be expected. § 574. Muscular Groups.—It is sometimes convecient to speak of two or more muscles collectively as a group, as, e. g., the pecto- ralis group, the trapezius group, the triceps group. PARTS OF A MUSCLE. 195 § 575. Subdivisions——As has been well stated by Humphrey (BE, 110), the longitudinal subdivision of a muscle may be either vertical or horizontal. For the sake of distinctness, we shall cail the subdivisions of the former kind divisiones, and those of the lat- ter lamine. For example, as has been remarked by the senior author (20, 306), the ‘‘ Jf. ectopectoralis (Fig. 72) tends to separate into superimposed laminz, while the entopectoralis tends to form fasciculi”’ In the former the “ cleavage”’ is horizontal, in the lat- ter vertical. § 576. Parts of a Muscle.—The essential and usually largest portion of a muscle is the mass of muscular fibers ; this is called its body or belly. Sometimes one—rarely if ever both—of the ends of a muscle is attached to bone directly or rather to its periosteum. This is the case with the humeral end of the IZ. brachialis (Fig. 74, § 692), and the IL. entotriceps, div. intermedia (Fig. 75, § 686). More often, however, there intervenes between the muscular por- tion and the bone a cord or sheet of white inelastic fibrous tissue, constituting the tendon. The attachment is then said to be tendi- nows, while in the former case it was muscular. Tendons may be so short as to be hardly distinguishable, like the coracoid tendon of the Jf coracoideus (§ 668), or they may be longer than the muscular portion, like the humeral tendon of the same muscle (Fig. 75). Sometimes, especially with thin flat muscles like the lamine of the IZ. ectopectoralis (Fig. 72), the tendinous sheet may be so short as to be practically absent. § 577. Attachment Lines and Areas.—Muscular attachments usually, and tendinous attachments sometimes, cover considerable areas (brachialis, Fig. 68); in other cases the attachment is along lines (entopectoralis, divisio caudalis, Fig. 69). § 578. Origin and Insertion.—Of the two attachments of a mus- cle, one is called origin and the other insertion. Usually, but not always, the origin is from the more fixed part of the body, and the insertion is upon the more movable part. § 579. Choice of Origin and Insertion.—With the membral muscles, one attachment is generally nearer the soma (§ 54) or the proximal end of the limb, and this attachment is always called the origin. Thus the scapular attachments of the IZIZ. biceps (Fig. 75) and subscapularis (Fig. 73) are the origins of those muscles; so 196 ANATOMICAL TECHNOLOG Y. also, the origins of the WM. entopectoralis (Fig. 72) and clavo- trapezius (Fig. 66) are, respectively, their sternal and vertebral attachments. But the question is less easy with some muscles which connect different parts of the soma with each other, or which extend between the head and the scapula, clavicle or sternum. Without feeling sure as to what is best, we have adopted the following basis :— As between the head and the neck or the trunk, the latter are more central and afford origin to the muscles of the head. The sternum is part of the trunk, and sternal] attachments are therefore origins. The scapula and clavicle appertain to the arm rather than to the trunk, and attachments thereto, as compared with attachments to the head or neck or trunk, are insertions. It will be seen that the acceptance of these rules entails some apparent contradictions : For example, the clavo-mastoideus (Fig. 67), like the clavo-trapezius (Fig. 66), arises from the skull and is inserted upon the clavicle; but the sterno-mastoideus (Fig. 67), like the splenius (Fig. 67), arises from the trunk and is inserted upon the skull. Hence the origin of the clavo-mastoideus practically coincides with the insertion of the sterno-mastoideus. In man, where the clavicle joins the sternum, the two muscles are commonly described as one, under the name of sterno-cleido-mastoideus, and one part of the muscle therefore arises where the other is inserted, and vice versa. § 580. The Determination of Muscular Homologies.—Of course the function of a muscle depends upon its insertion, but there is considerable difference of opinion as to whether the origin or the insertion is the better guide to the determination of its homology. We are disposed to assign greater morphical importance to the ori- gin, according to the views of Barnard (1, 114). As to the value of vascular and nervous supply, see Cunningham (7) and Gadow (3). § 581. Fascia.—This is simply a thin sheet of the same kind of fibers as the tendon, but the fibers may present two kinds of ar- rangement. Sometimes the tendon itself is so thin as to be called a fascia, or it may be continued as a thin sheet upon one or the other face of the muscle; in both these cases, the fibers are nearly or quite parallel. The name fascia, however, is more often given to a sheet of fibers crossing one another in various directions, and forming a sheath or covering fora muscle or a group of muscles. A fascia is also called an aponeurosis, but the name is objectionable on account of both length and etymology. § 582. Forms of Muscles.—The body of a muscle may be fusi- form or spindle-shaped, like that of the If, biceps (Fig. 78); teni- ate (strap-shaped or ribbon-like), as with the occipito-scapularis (Fig. 67); fan-shaped like the subscapularis (Fig. 78); quadri- APHORISMS FOR DISSECTORS. 197 lateral like the acromio-trapezius, or triangular like the spino-tra- pezius (Fig. 66). There are other and less usual forms which will be indicated in special cases. § 583. Designation of the Borders of Muscles. tees of the muscles are thin and triangular or teniate, so as to present sharply defined borders, in place of the more or less rounded aspects or sur- Jaces of a fusiform muscle like the diceps. Such a flat muscle may become twisted upon its axis in such a way as to change the relations of the borders to the body-planes. In these cases, for the sake of convenience, it will be considered that the muscle has the general direction which it had at its origin, al- though this may sometimes involve an apparent contradiction of the terms in which the insertion is described. For example, the IZ. pecto-antebrachialis, dv. cephalica (Fig. 72), arises at the meson, and its borders are called cephalic and caudal throughout its whole length, notwithstanding the fact that the line of insertion upon the ulna has a proximo-distal direction, so that, as based thereon, the borders would be prozimal and distal. § 584. Connect.—For the exposure of the ectal layer of muscles, certain areas of skin must be lifted. The lines of incision which circumscribe such areas are said to ‘‘connect’’ certain parts or points, usually some of the ‘‘landmarks”’ elsewhere (§$§ 225-233) enumerated. § 585. Girdle.— When the skin, especially of a limb, is divided by an incision encircling the part, the latter is said to be ‘‘ girdled.” § 586. Transect.—In order to examine fully the attachments of a muscle, it is usually desirable to divide it transversely and reflect the two ends in opposite directions. For the sake of brevity, this entire operation will be indicated by the use of the single word transect. APHORISMS FOR DISSECTORS. § 587. 1. ‘* Without skilful manipulation we can neither teach by demonstration facts which have been already discovered, nor hope to extend the limits of observation and experimental knowl- edge.”’—L. 8. Beale, A 2. ‘‘A piece of true dissection ought to turn out an object of wonder and beauty.’’—Goodsir, A, I, 24. 3. ‘An anatomist therefore in these curious things had need to have a fine and dainty hand, and at command.’’—Crooke, A, 460. 198 ANATOMICAL TECHNOLOGY. 4, ‘‘The best workman uses the best tools.’’—Owen. 5. The value of instruments depends not upon their handles, their finish or their cost, but upon the adaptation of their size, form and temper to the work in hand. 6. Fingers are often the best forceps. 7. Handling and cutting are necessary evils. 8. Neglect of the knife may leave the truth concealed ; its misuse may establish an error. 9. ‘‘Let the eye go before the hand, and the mind before the eye.”’—O. W. Holmes. 10. Fat is the anatomist’s worst enemy. 11. ‘‘ Drying is even worse than decomposing.’ —R. M. Hodges. 12. The skin makes the best wrapper. 13. There are two sides, but only one meson. 14. The bones are the guides to the muscles, the muscles to the vessels, and the vessels to the nerves. 15. The attachments of a muscle determine its homology and function; the thickness and length of its body indicate respectively its power and the distance through which it may contract. 16. The attachments of a muscle are often closely associated with those of others, but its body is usually distinct. 17. In dissecting muscles, the science consists in discriminating between fascia or tendon and mere connective tissue; the art, in removing the latter so as to leave the muscles distinct. 18. Dissection according to direction favors the acquisition of methods and the learning of names and specified relations ; but the knowledge of parts is not complete until they have been approached and examined from all sides. See also § 122. § 588. List of Instruments and Materials for the Dissection of Muscles.—Arthrotome, Fig. 16, § 135; blocks, § 137; coarse forceps, Fig. 18, 145 ; fine forceps, Fig. 20, § 146; scalpels, medium and Charricre, Fig. 23, 24, § 155; coarse scissors, curved flatwise, Fig. 25, § 156 ; hair scissors, § 158; towels, § 165; sharp tracer, Fig. 17, § 166; tray, § 167; waste pail, § 195; waste papers, § 172; wetting bottle, Fig. 27, § 170. § 589. The Material for Dissection.—A lean animal should be preferred ; it should be divided by abdominal transection (§ 234) ; injected with alcohol (§ 285), but not—for the first dissection—with plaster ; kept in 42-55 per cent. alcohol (§ 286), and not allowed to dry. USE OF THE SCALPEL. 199 HOW TO USE DISSECTING INSTRUMENTS. § 590. Hyrtl complains (A, 62) that ‘‘some people hold the for- « ceps like fire-tongs, and the scalpel like a cheese-knife.”’ It is true that most anatomical instruments are for either grasping or cutting, but their proper and successful employment demands much more care and delicacy than is needed in ordinary household operations. The good whittler is not necessarily an expert dissector, and even the coarse scissors are to be handled very differently from shears. The anatomist, like the surgeon—who is an anatomist and some- thing more,—should have such command over his muscles and nerves that whatever instrument is in his hands becomes for the time being like a part of himself, an extension of his fingers, sharper, firmer and more slender, yet almost equally mobile and sensitive. Fig. 63.—THE ScaLPEL HELD As A PEN. (From Bernard). § 591. Use of the Scalpel (§ 155).—The scalpel may be held in either of three general ways :— A. Like a Pen (Fig. 63).—The edge is directed backward and downward, or forward and upward. This is for ordinary dissection. B. Like a Carving-knife (Fig. 64).—The edge may be directed upward or downward. This is for the division of more resisting tissues. C. Like a Violin-bow (Fig. 65).—The scalpel is held between the tip of the pollex on one side and the tips of the other digits upon the 200 : ANATOMICAL TECHNOLOGY. other. This is for long sweeping strokes, where the greatest freedom is desired. Minor modifications of these three ways will be readily adopted as the dissector becomes familiar with the instrument. Fie. 64—THE SCALPEL HELD AS A CARVING-KNIFE. (From Bernard). § 592. Use of the Scissors (§ 156).—Contrary to the more usual custom, dissecting scissors should be held with the pollex and me- dius. The index then serves both to steady the instrument and to Fie. 65.—THE ScALPEL HELD As A VIOLIN-Bow. (From Bernard). aid the medius in its opposition to the more powerful pollex. In nearly all cases the points of curved scissors should be turned wpward and away from the part under dissection. This precaution is es- THE USE OF INSTRUMENTS. 201 pecially needful in the trimming of vessels and nerves and inflated hollow viscera (§ 331). § 593. Use of the Forceps (§ 145).—The forceps are commonly held between the pollex and the index. In long continued dissec- tions the medius may be substituted for the index at intervals. The digits should be employed in place of the forceps when practicable, both as a relief from fatigue and to avoid crushing the tissues. The forceps should be used upon muscles as little as possible, and vessels and nerves should be grasped by their sheath of con- nective tissue. For the separation of slender muscles and of vessels and nerves, the safest way sometimes is to insert the tip of the closed forceps and then allow the blades to separate gently. § 594. Use of the Tracer (§ 166).—The tracer is to be held like a pen or pencil. Its form permits a rotation on its axis, so that the point may have any desired direction. The tracer should be more constantly in the hand than any other instrument. Scalpels and other sharp instruments should only be used when the tracer will not answer the purpose. The tracer is also very useful in detecting the position of con- cealed hard parts, as ribs, cartilages and vertebree. The point may be introduced deeply without impairing the condition of the parts for dissection, and the curvature enables one to lift upon it the ribs or cartilages so as to count them more accurately. § 595. Use of the Arthrotome (§ 135).—As its name implies, the distinctive use of this instrument is for the division of joints and other rough operations which might injure the more delicate edge of the scalpels. Yet the student should accustom himself to accu- rate and careful manipulation, and endeavor to separate the contig- uous bones at an arthron without injuring the cartilages. He should try to feed with the point of the instrument. PRACTICAL SUGGESTIONS FOR DISSECTORS. § 596. 1. Select a lean animal for all anatomical purposes, and especially for the dissection of the muscles, vessels and nerves. The directions for killing are given in § 192. 2. Take the precautions for cleantiness which are described in § 199. 3. Remove superfluous parts of the animal, the tail in some cases ($ 243), the caudal or cephalic region of the body, according to the 202 : ANATOMICAL TECHNOLOGY. directions for abdominal and thoracic transection which are given in $$ 237, 242. 4. See that all the instruments, materials and books for dissec- tion, reference and record are at hand and in order before getting the subject or beginning to work. 5. Refer constantly to a skeleton, or to the bones especially con- cerned, or to accurate figures. 6. Have plenty of Zight upon the part under dissection, so that details of structure may be seen. 7, When a part from which or toward which an incision is to be carried lies upon the meson, the incision should extend 1-2 cm. beyond the meson. This permits the flap of skin to be reflected across the meson to that extent. If, however, this flap of skin is to be removed, the incision removing it should run parallel with the meson, and upon the side under examination. Objections to Mesal Incisions—Both the ectal and ental aspects of the skin present spe- cial features at some mesal points, and several muscles besides those of the skin itself arise at the meson, and are liable to injury by a mesal incision. There are two sides, presuma- bly similar, but there is only one meson. 8. Incisions should be as long as may be consistently with the shape and structure of the parts, and the dissector’s knowledge of them. 9. When important or delicate parts are liable to be injured, the cuts should be shorter and more carefully made. 10. Vessels and nerves should be dissected from the center toward the periphery, so as to avoid the risk of missing, cutting or tearing the branches. 11. Vessels injected with plaster should be divided with the arthrotome or the bone scissors. 12. In place of the block, especially while the separated arm is under dissection, a folded wet towel may be used; this permits a kind of bed to be made which keeps the arm in place. 13. “To put any group of muscles on the stretch, put the parts concerned in the position into which they would be brought by their antagonistic muscles. For example, to put the flexors of the manus on the stretch, put the manus in a state of extension, and vice versa.’’—Heath (Keen), A, 16. 14. Study the actions of a muscle by pulling it in the line it nat- urally occupies. Note the difference between a direct and an indi- rect action. (Wilder, 4.) SUGGESTIONS FOR DISSECTORS. 203 15. As arule, muscles must be divided and reflected before the attachments can be fully determined. The attachments are usually more distinct upon the ental aspect. 16. ‘‘ When several similar muscles of a group—as those upon the antebrachium—are to be transected, cut them at different levels, so as the more easily to match their proximal and distal parts.’’— Heath (Keen), A, 16 17. The borders of a thin muscle should be grasped and slightly raised, first with the forceps and then with the fingers. If the other border is accessible, it should be treated in the same way, and then the entire width at about the middle raised to permit the passage of a scalpel. 18. In transecting a wide muscle, cut one border, then lift it, keeping the sides of the cut separate, and cut a little deeper, applying the scalpel to the edge of the muscle. 19. Avoid cutting muscles at theirattachments. If it is desirable to remove part of a large muscle, leave a small piece of the body attached to each tendon. If necessary—for special reasons—to re- move an entire muscle, insert the edge of the arthrotome in the angle formed by the attached ends and the bones. 20. Parts under dissection should be wet occasionally with a mixture of water, glycerin and clove-oil (§ 170). 21. Parts which have been exposed, but are no longer under actual dissection, should be covered with skin or rubber-sheeting, or with a bit of cloth wet with the glycerin mixture; and a dry towel should be laid over all. 22. “ Put all fragments on a piece of paper.” —Hodges, A § 597. Avoid especially the following: drying, tailing, pecking. The prevention of drying has been already considered. Tailing is the making of a shallow cut at the beginning or the end of an incision. It is especially apt to occur with beginners, and while dividing the skin. To avoid it, hold the point of the scal- pel perpendicularly to the surface at both the beginning and the end of the incision. Pecking.—We use this homely word to designate one of the most common and most pernicious faults of anatomical beginners, the habit of aimlessly poking and pinching the parts, espe- cially while showing them to the teacher or demonstrator. It reminds the observer of nothing so much as the dabbing and peck- ing which hens inflict upon a piece of meat. The student should 204 ANATOMICAL TECHNOLOGY. bear in mind that a single false cut, and even a pinch in the wrong place, may mar his work beyond repair; he should exercise con- stant self-control, and never touch the specimen excepting for a definite and sufficient reason. Pecking is only one of several forms of what may be called anatomical Philistinism; a lack of appreciation of delicacy, whether in structure or in methods of manipulation. § 598. Clipping the Hair.—Unless the skin is to be preserved, or there is some other objection, the hair should be removed from a specimen which is to be preserved in alcohol and dissected at intervals. If the hair is allowed to remain, it interferes with the accuracy of dermal incisions, and with the ease of making them ; it is apt to become detached and disfigure the dissections : finally, unless considerable time is spent in squeezing out the alcohol when the specimen is removed from the jar and the water when it is returned thereto, the hair causes both a waste and a weakening of the alcohol in which the specimen is preserved. Use the hair scissors (§ 158) or a pair of ordinary scissors with the points blunted. The hair is more easily cut against its inclina- tion, that is, with the scissor points directed cephalad upon the soma and proximad upon the limbs. After abdominal transection, begin at the cut border of the skin. Clipping is facilitated by wetting the tips of the hair with a sponge only moderately full of water or weak alcohol. Cut close to the skin. The operation usually occupies about an hour. Do not put the removed hair into the sink. Place it in the waste-pail, to be buried. § 599. Cutting the Skin.—If the hair remains, wet it with 15 per cent. glycerin, or dilute alcohol, or water, along the line of the proposed incision. Then, with a small comb, or the tracer, or the handle of a scalpel, part the hair evenly along the same line so as to expose the skin clearly (§ 354). If the hair has been removed, indicate the line of incision by a scratch made with the tracer or the point of the scalpel. Place the tips of the left index and medius, one upon each side of this line, at the cut border of the skin, and divaricate them so as to stretch the intervening skin. Grasp the scalpel like a pen, at an angle of 45°, and divide the skin by a single steady stroke as far as the tension exists. At the beginning and end of the stroke, make the scalpel nearly perpendicular so as to avoid tailing (§ 597). REMOVING THE SKIN. 205 Unless one is quite familiar with both the locality and the art of dissecting, this first incision should merely divide the skin proper. The borders may be still farther divaricated, and a similar incision . made through the connective tissue and fat, and in some cases the dermal muscle (§ 629), until the darker red and closer texture shows that the ordinary skeletal muscles have been reached. - With lean animals this second incision will be very shallow, but in some cases the fat forms thick layers between the dermal mus- cles and the skin and deeper muscles. On the cheeks of old males, and sometimes on other regions, the skin and connective tissue are so thick as to puzzle the beginner. Shift the tips of the index and medius, and repeat the operation to the end of the line. The separate strokes should join each other accurately, so that the entire incision is straight and smooth-edged. After the skin is divided, the subcutaneous fat and connective tissue may usually be cut to the proper depth by a single long steady stroke. § 600. Removing the Skin.—The edge of the area of skin to be removed, preferably at the angle formed by two incisions, should be grasped, first by the forceps and then by the fingers, and lifted so that the scalpel may be applied to the connective tissue by which it and the fat are held loosely to the deeper muscles. Excepting in the case of some rare form (which should not be dissected by a beginner), the skin should be kept well upon the stretch, and the edge of the scalpel should be applied against the tissues to be exposed, following the direction of the muscular fibers. The object is to remove with the skin all the subcutaneous fat, con- nective tissue and ectal fascia, so as to expose at once and fully the surface of the muscles, etc., to be examined. This, the anatomical method of removing the skin, is more diffi- cult than the “ flaying’’ of the butcher or the “‘skinning”’ of the taxidermist. Both of these desire the skin free of fat and connective tissue, and therefore keep the edge of the knife turned toward it. The taxidermist must avoid stretching, but this is easier than to follow strictly the above method. The beginner will usually be tempted to get the skin off in the easiest and quickest way, which is that of the butcher; but he then is obliged practically to repeat the operation for the removal of the tissues which should have been lifted with the skin. § 601. Rigor Mortis.—The spontaneous stiffening of the mus- 206 ANATOMICAL TECHNOLOGY. cles which supervenes soon after death renders dissection difficult. The condition usually passes off within a few hours, and may be speedily overcome by immersing the animal for 40-60 minutes in. water at about 35° C. (95° F.). DESCRIPTIONS OF CERTAIN MUSCLES. § 602. Limitation.—For the reasons stated in § 128, the myological portion of this work directly relates to only about one fifth of the whole number of muscles which have been enumerated in the cat. As with the bones, however, (§ 368), the student is advised to pursue the subject further, making original drawings and descriptions of at least one muscle in another part of the body. Whether it can be at once identified with some mus- cle in man is of less importance, so far as the training of the pupil is concerned, than the accurate determination of its connections and other characters. § 603. The Method here Followed.—With few exceptions, each of the forty muscles here considered is described under the following heads :— 1. Synonymy.—We have given the names for the same muscle employed by Straus- Durckheim and Mivart, and the names for what appears to us to be the homologous mus- cle in man and in the horse. The anthropotomical names are taken from ‘‘ Gray ” and “ Quain,” and the hippotomical ones from the French and the English (Fleming’s) editions of “Chauveau.” In some cases, we have been unable to satisfy ourselves as to the homol- ogy. We should have been glad to include references to the works of Leyh (A) and Gurlt (A) upon the horse, to Krause’s Anatomy of the rabbit (A), and to Coues’s paper on the opossum (47). The authors’ names are indicated by the initial letters only. 2. Figures.—Here are enumerated the figures wherein the muscle appears. 3. General Description.—This is a brief indication of the general form and connections. 4, Posture.—We have indicated the position of the body or limb which seems most favorable to the examination of the muscle. 5. Exposwre.—Here are given directions for bringing the muscle into view by the removal of the skin or overlying parts. 6. Dissection.—This includes the operations by which the borders of the muscle are to be raised, its body transected and the ends reflected so as to display the attachments. Vand 8. Origin and insertion.—Here are given more detailed descriptions of the two attachments. In addition to the above, a complete account of each muscle should embrace its nervous and vascular supply, its actions, direct, indirect and associated, and its variations. Errors and Defects.—During the past four years the descriptions and directions here given have been employed by the students in the anatomical laboratory of Cornell Univer- sity. Inasmuch, however, as annual modifications have been found necessary, we cannot hope that their present form is altogether what it should be, and we shall be very grate- ful for the correction of errors and the pointing out of defects. We desire here to repeat the expression of our sense of obligation to Prof. T. B. Stowell, who has kindly followed the descriptions and directions scalpel in hand, and has given us the benefit of many valuable suggestions and criticisms as to both the facts and the method of stating them, and as to the extent of variation in different individuals. A former special student, Dr. E. M. Howard, generously placed at our disposal for comparison his manuscript descriptions of the muscles of the cat. § 604. The Names of the Muscles.—The number, extent and nature of the changes proposed in the names of the muscles are set forth in the Table on p. 207. In that Table the names in the left hand column are those adopted in the present work ; TABLE OF THE MUSCLES. 207 those in the right hand column are Latinized from those employed by Straus-Durckheim ; those in the middle column occur in standard works upon Human Anatomy, or in the writings of anthropotomists. In the last column are words or abbreviations indicating the changes which have been made in the names employed by Straus-Durckheim (8.-D.) or anthropotomists (anth.): thus, abbrev. = abbreviated; tr’l’d = translated; unif. = unified. § 605. TABLE, Here Adopted. Fig. Anthropotomy. Straus-Durckhein. Changes. Spino-trapezius.....] 66 | Trapezius (in part). .| Dorso-cucullaris ..,.| §.-D., unif. & tr’l’d. Acromio-trapezius ..| 66 ss a ..| Acromio-cucullaris..| 8.-D., translated. Clavo-trapezius..... 66 * i ..| Clavo-cucullaris....) 8.-D., translated. Occipito-scapularis...| 67 | Rhomboideus capitis, Occipito-scapularis..| 8.-D. Rhomboideus...... 67 | Rhomboideus major.) Rhomboideus...... 8.-D.: anth., abbrev. Sterno-mastoideus .. Clavo-mastoideus... Levator clavicule.. . Dermo-humeralis... Latissimus......... Clavo-deltoideus.... Pecto-antebrachialis. Ectopectoralis...... Entopectoralis...... Xiphi-humeralis.... Serratus magnus... Levator scapule.......- Coracoideus........ Subscapularis Supraspinatus...... Spino-deltoideus. .. Acromio-deltoideus.. Infraspinatus. ..... Micostalis.......... TOPOS. osock 5 areca bt a Epitrochlearis...... Meditriceps...... Sia Ectotriceps......... Entotriceps Supinator longus... Biceps...........4- Brachialis.......... Extensor (carpi) t radialis longior. Extensor a radialis brevior. Extensor communis. Extensor minimi... Extensor ulnaris... Indicator Pronator teres...... Flexor radialis .... ‘Subscapularis ; Sterno mastoide- us (in part)... t | Sterno-mastoide- } us (in part)... t Levator clavicule.. . Latissimus dorsi.... Deltoideus (in part). Pectoralis major.... Pectoralis minor.... Serratus magnus... Lev. ang. scap...... Coracoideus....... ‘ Supraspinatus...... Deltoideus (in part). ca “ce Infraspinatus....... Teres minor........ Teres major........ Dorso-epitrochlearis Triceps (in part).... | Triceps (in part) and anconeus... Supinator longus... Biceps Brachialis anticus... Ex. carpi rad. longior....... { oe carpi rad. t brevior ....... Ex. digitorum com. . Ex. minimi digiti... Ex. carpi ulnaris.... .| Extensor indicis.... Pr. radii teres...... Fix. carpi radialis .. Sterno-mastoideus. . Cleido-mastoideus. . Transv.-scapularis .. Dermo-humeralis. . . Latissimus dorsi. ... Delto-clavicularis. .. Pecto-antebrachialis Large pectoral...... Grand pect. (in part) and sterno- trochiterianus.. Grand pect. (in part). Serr. mag. (in part). “ “ec Coraco-brachialis. .. Subscapularis...... Supraspinatus...... Delto-spinalis...... Delto-acromialis.... Infraspinatus Micostalis.......... Triceps (in part).... Triceps medius..... Triceps externus.... } Tri. int. (in a and anconeus. Supinator longus... Biceps. .......005-: Brachialis Radialis primus... . Radialis secundus.. . Ex. dig. communis. . Ex. proprius minimi Cubitalis..... eeees Indicator Pronator teres...... Cercialis........... 8. D. & anth. S. D., translated. Anth., 8.-D. 8.D.; anth., abbrev. 8.-D., transposed. 8. D. Gen eralized, Generalized. New. Auth. and 8.-D, .| Anth, Anth., abbrev.; 8.-D. Anth. & 8.-D. Anth. & S.-D. 8.-D., transposed. 8.-D., transposed. Anth. & §.-D. 8.-D. 8.-D.; anth., abbrev. Anth., abbrev. 8.-D., abbrev. Generalized. 8.-D., abbrev. Anth. & 8.-D. Anth. & §.-D. « 8.-D.; anth., abbrev. Anth., abbrev. Anth , abbrev. Anth., abbrev. Anth , abbrev. Anth., abbrev. 8.-D. 8.-D.; anth., abbrev. Anth., abbrev. 208 ANATOMICAL TECHNOLOGY. Where more than one name is used in Human Anatomy, the shortest is here given; the coracoideus, for example, is often called coraco-bruchialis, and the sterno-mastoideus, sterno-cleido-mastoideus. The occipito-scapularis, lerator clavicule and dorso-epitrochlearis occur in man only as anomalies, and have received names in addition to those here selected. The names employed by Straus-Durckheim have been put into their classical and tech- nical form, excepting in the case of the “large pectoral” and ‘grand pectoral.” It is probable that one cause of the slight use made of the names of this eminent anatomist is the fact that he chose to publish them in the vernacular form. § 606. The Sources of the Names Here Used.—Of the names of the 40 muscles here described, seven are employed both by Straus-Durckheim and in the standard works upon Human Anatomy; these are: sterno-mastoideus, serratus magnus, subscapularis, supraspi- natus, infraspinatus, biceps, and supinator longus. The following three names have been applied in Human Anatomy, but are not used by Straus-Durckheim : levator clavicule, levator anguli scapule, and coracoideus. The following nine names are used by Straus-Durckheim, but not by anthropotomists : oceipito-scapularis, rhomboideus, micostalis, teres, brachialis, indicator, pronator teres, dermo- humeralis, and pecto-antebrachialis. The last two refer to muscles which do not exist in man, and four of the others are but slight modifications of the anthropotomical names. The following eight names are abbreviations of the anthropotomical names : latissimus, epitrochicaris, extensor radialis longior, ex. rad. brevior, ex. communis, ex. ulnaris, ex. minimi, and fleor radialis. The following seven names are translations or transpositions of those used by Straus- Durckheim: acromio-trapezius, clavo-trapezius, spino-deltoideus, acromio-deltoideus, clavo- deltoideus, clavo-mastoideus, and meditriceps. As to the hybrid nature of some of these terms, see § 53. The following four names are the names in common use modified after the analogy of the now almost universally adopted ectogluteus : ectopectoralis, entopectoralis, ectotriceps, entotriceps. Two names remain to be accounted for. One of these, spino-trapeztus, was substituted for Straus-Durckheim’s dorso-cucullaris for the sake of uniformity with respect to the other divisions of the human trapezius, and the correlative division of the deltoideus. This leaves us responsible for but one entirely new name, wiphi-humeralis. While the muscle so designated seems to us sufficiently distinct to demand a separate appellation, we are not particularly pleased with the name, and stand ready either to accept a shorter one or to regard the muscle as only a division of the ectopectoralis or entopectoralis when the proper evidence is forthcoming. THE TRAPEZIUS GROUP. §°607. General Remark.—The human UW. trapezius, a single muscle, seems to be rep- resented in the cat by three nearly distinct muscles, which are here called—beginning with the most caudal—spino-trapezius, acromio-trapezius, and clavo-trapezius. They extend from the cervical and thoracic dorsimeson to the scapula and clavicle. The names of all the muscles are in italics. To avoid frequent repetitions, the capital M, the initial of Musculus, will be prefixed only when otherwise there might be some risk of misunderstanding. § 608. Explanation of Fig. 66.—The left ectal skeletal muscles of the neck and shoulder. THE TRAPEZIUS GROUP. 209 Preparation.—A subtriangular flap of skin was lifted as di- rected in § 610, together with the dermal muscles connected there- with. The flap was reflected dorsad, but is omitted from the figure ; the reflected dorsal end of the dermal muscle called supra-cervico- cutaneus, however, is shown. Both cut edges of the skin were lifted and retracted or reflected slightly. The dermo-humeralis (§ 629) was mostly removed with the skin, but its brachial end appears just dorsad of the elbow. The fat and connective tissue have been removed so as to leave the borders of the muscles more distinct. From the hiatus trapezii, just dorsad of the convexity of the shoulder, the fat has been removed so as to expose the lymphatic gland (Gl. lymphatica), and the hiatus itself was extended dorsad so as to expose the ventral or lateral margin of the occipito-scapularis. In this and the other descriptions of the myological figures, the parts are enumerated under three heads: bones, etc. ; muscles ; vessels, nerves, glands, etc. Bones.—Clavicula—Collar bone (§ 422).—In this figure the bone itself does not appear, but the position of its mesal or sternal end is indicated by the dotted line from the word clavicula ; see rhaphé. Mesoscapula—Spine of the scapula (§ 390).—The position of this ridge of the scapula, intervening between the MM. acromiv-trapezius and spino-deltoideus, is approximately indicated by the name. It is more distinctly shown in Fig. 67. Metacromion (§ 396).—This process of the glenoid end of the mesoscapula may be felt through the muscles at a point corresponding with the beginning of its name. Fascia.—This strip of fascia—hardly deserving the name of ligament—passes from the lateral or scapular end of the clavicle to the surface of the M. supraspinatus, as better shown in Fig. 67. Rhaphé (trapezio-deltoidea) (§ 616).—This line or seam of connective tissue, between the M. clavo-deltoideus and the MM. clavo-trapezius and clavo-mastoideus (Fig. 67), coin- cides nearly with the position of the clavicle. It is usually more distinct upon the ental aspect, and is somewhat exaggerated in the figure. The word is sometimes spelled raphé. Spine neurales vertebr. (vertebrarum) thoraci. (thoracicorum),—The third and thirteenth thoracic (‘‘ dorsal’) neural spines (Fig. 30).—The spines themselves do not appear, but the numbers 3 and 13 indicate the positions of the third and the last of the series. Muscles.—In the figure the name of each muscle is preceded by IM, the initial of Museulus. Acromio-deltoideus—The acromial portion of the deltoid (§ 670).—This is the interme- diate one of the three muscles which, in the cat, seem to represent the single deltoid muscle of man. It and the spino-dedtoideus are inserted, like the human deltoid, upon the humerus; but the third portion, the clavo-deltoideus (the ‘‘delto-claviculaire” of Straus-Durckheim) is associated with the brachialis and inserted upon the ulna. Acromio-trapezius—The acromial portion of the human trapezius (§ 613).—This is the intermediate one of the three muscles which, in the cat, appear to us to represent the human trapezius (§ 607). In the figure the name is written obliquely across the scapular end of the muscle; the word tendon, near its vertebral end, indicates the imperfectly 14 210 ANATOMICAL TECHNOLOGY. defined tendon of origin (§ 614). Upon the muscle are also written the names M. occipito- scapularis, hiatus trapezti, and Gl. lymphatica. Cervico-auricularis (§ 615).—This muscle of the ear is shown at the dorsimeson between the ear and the M. supra-cervico-cutaneus ; its name is omitted. Clavo-deltoideus (§ 637).—See also acromio-deltoideus. Clavo-trapezius (§ 615).—See also acromio-trapezius. Dermo-humeralis (§ 629).—Most of this dermal muscle was removed with the skin; the name is written across the brachial end which passes between the MW. triceps and latissi- mus to be attached to the latter and the bicipital arch. Latissimus (§ 635).—This is more commonly called latissimus dorsi. Its caudal por- tion is covered by the skin; its dorso-cephalic angle is overlapped by the spino-trapezius, but exposed in Fig. 67. Levator clavicule (§ 627).—The scapular end is seen to emerge from entad of the clavo- trapezius, to partly overlap the acromio-trapezius and to be inserted upon the imperfectly defined metacromion rather than upon the clavicle, as might be supposed from the name. Occipito-scapularis (§ 617).—This is fully shown in Fig. 67. Here, its lateral border appears at the dorsal end of the hiatus trapezii which has been enlarged so as to show the position of the muscle. Spino-deltoideus (§ 674).—See also the acromio-deltoideus. Spino-trapezius (§ 611).—See the acromio-trapezius. Sterno-mastoideus (§ 622).—Part of this shows darkly between the skin of the neck and the clavo-trapezius. It is more fully shown in Fig. 67 and 72. Supra-cervico-cutaneus (§ 615)—Most of this cervical dermal muscle was lifted with the skin, and only its reflected dorsal end is shown. Teres (§ 680).—This appears in the interval between the spino-trapezius, spino-deltoideus, latissimus and triceps. By inadvertence, the name is written with the addition of the qualifying adjective major ; since the muscle more often called teres minor is here desig- nated as micostalis, there seems to be no need of a compound term for the muscle in question. Triceps.— The name is written across the two largest portions of the muscle commonly Known as triceps in man. The M. is upon the scapular head, here called meditriceps (§ 682), and most of the rest of the name is upon the part here called ectotriceps (§ 684); the surface of the latter presents a superficial furrow. Other Parts.—Gt. (glandula lymphatica).—A somewhat large lymphatic gland embed- ded in the fat which occupies the hiatus trapezii. Gl. (glandula) parotis—The parotid salivary gland (Fig. 87).—The caudal border of this usually pale gland is exposed by slightly cephaloducting the occipito-presternal edge of skin. Gl. (glundula) submazillaris—The submaxillary salivary gland (Fig. 87).—This appears a little ventrad of the Gl. parotis, and is usually of a deeper color. Hiatus trapezii (§ 613).—This is an elongated lozenge-shaped interval between the cephalic margin of the M. acromio-trapezius and the caudal and dorso-caudal margins respectively of the MM. clavo-trapezius and levator clavicule. In reality, the very open angle formed by the intersection of these two borders is near the middle of the length of the hiatus, but in the preparation the margins of the MI. clavo-trapezius and acromio- trapezius have been artificially separated a little farther dorsad. V. (vena) jugularis—The jugular vein (Fig. 101).—This is exposed between the UW. clavo-trapezius and the margin of the skin, where it obliquely crosses the M. sterno-mastot- deus. § 609. Exposure.—It is usually more convenient to expose the THE TRAPEZIUS GROUP. 211 entire trapezius group by lifting a single large flap of skin. This flap, however, may be divided afterward so that one or two of the muscles may be covered while the other is under examination. In so doing, the skin is more easily divided ento-ectad (from within outward). fic. 66—THE EcTaL SKELETAL MUSCLES OF THE LEFT SHOULDER AND NECK, AFTER REMOVAL OF THE DER- / MAL Musciges. (The left side of the head is shown ja outline below in order to facilitate the student’s recogni- tion of the regions in this his first systematic dissection.) 212 ANATOMICAL TECHNOLOGY. § 610. Caution.—In making all incisions through the skin of the cat, it is necessary, in addition to the general directions in § 599, to keep in mind the presence of the Jf. dermo-humeralis (§ 629) and other muscles constituting the panniculus carnosus, a thin muscu- lar layer between the skin and the proper skeletal muscles. The dermal muscle is usually to be divided and lifted with the skin. With fleshy animals, the risk of cutting at the same time the underlying skeletal muscles is obviated by the intervention of a layer of fat which should also be removed with the skin (§ 600). With lean animals, the two sets of muscles may usually be distin- guished from the thinness and paleness of the dermal layer, and from the fact that it is moved when the skin is pulled in any direction. Connect (§ 584) the presternum (Fig. 30 and 49, § 228), with the thirteenth thoracic neural spine (Fig. 30 and 66, § 227), and with a point 1 cm. cephalad of the crista lambdoidalis (Fig. 56, § 226). The occipito-presternal incision should have a slight caudal con- vexity so as to skirt the base of the ear. The vertebro-presternal incision should cross the brachium at about the junction of its first and second fourths; this incision may be commenced at the middle of its length, and be carried thence in both directions. Lift the flap at the presternal angle, and remove with the skin the fat, connective tissue and dermal muscles. Reflect it across the dorsimeson. M. SPINO-TRAPEZIUS. § 611. Synonymy.—The caudal part of the human trapezius, Q., A, 1, 187; G., A, 3873 ; dorso-ceucullaire, 8.-D., A, TI, 834; portion dorsale du trapéze, Ch., A, Fig. 90, “1,” 216 ; dorsal trapezius, Ch. (F1.), A, 203; hinder portion of the trapezius, Miv., B, 187. Figures.—Ectal aspect (66) ; insertion (67, 44); transection (99, 100). General Description.— An elongated triangle, from the thoracic dorsimeson to the mesoscapula and the surface of the J/IZ. supra- spinatus and infraspinatus. Dissection.—The ventro-caudal border will appear as a slightly saised line nearly parallel with the presterno-vertebral margin of the skin. In recent specimens the color of the muscle is usually a brighter red than that of the subjacent IZ. latissimus. Lift the border near its middle, and trace it mesad, noting that, about 1 cm. from the meson, the muscular fibers are replaced by a thin tendon which is not always easily separated from the subjacent muscle. Then trace the border ventro-cephalad, noting that it M, SPINO-TRAPEZIUS. 2138 thickens slightly as it crosses the vertebral border of the scapula, and ends upon the fascia covering the WZ. infraspinatus. Continue to lift the ventro-caudal border, and dissect up the middle part of the muscle as far cephalad as possible ; then pull it caudad, and at the same time dorsad or ventrad. This will indicate the cephalic border, which is much shorter than the other, and extends latero-ventrad from a point between the 1st and 4th tho- racic neural spines. The dorsal half of the cephalic border is muscular, and separable without much difficulty from the adjacent caudal border of the dz. acromio-trapezius. Opposite, or slightly dorsad ot, the vertebral border of the scapula, the border of the Af. spino-trapezius becomes tendinous, thin and indistinct, so that its true limits are best ascer- tained by pulling upon the muscular portion. It is also overlapped to some extent by the JZ acromio-trapezius. The cephalic border of the muscle may easily be traced, entad of the tendon of the AL. acromio-trapezius, to a point 8-10 mm. cephalad of the mesoscapula, and about the same distance from the nearest part of the border of the scapula. Here it terminates upon the fascia covering the Jf supraspinatus. The muscle should now be transected (§ 586), and the ental surface cleared of fat, especially near the attachments. § 612. Origin.—From the tips and interspinous ligaments of most or all of the thoracic neural spines. The attachment of the cephalic border may be at any point between the Ist and 4th spine, and that of the ventro-caudal border at any point between the 11th and 18th. The origin of the caudal 2-3 cm. is by a triangular tendon, the lat- eral angle of which is 1 cm. from the meson. ‘The rest of the muscle arises by fleshy fibers. Opposite the cephalic 3 or 4 spines there are sometimes slight intervals filled with loose connective tissue ; opposite the others, the corresponding intervals, when they exist, are occupied by a firm fascia which practically renders the attach- ment continuous across the spines. Insertion.— Along a curved s-shaped line obliquely crossing the mesoscapula (Fig. 44). The cephalic two thirds of the insertion is by a thin tendon 1-2 cm. long and 1-1.5 cm. wide, which is attached to the fascia upon the ectal aspect of the supraspinatus, and to the mesoscapular tuberosity which it crosses very obliquely. Here it joins the caudal and usually fleshy third of the insertion, which extends upon the fascia covering the infraspinatus at an angle of 214 ANATOMICAL TECHNOLOGY. about 45 degrees with the mesoscapula. On the ectal surface of the spino-trapezius, along the line of union of the muscular and ten- dinous parts, is received the insertion of the acromio-trapezius (Fig. 67). M. ACROMMO-TRAPEZIUS. § 618. Synonymy.—he intermediate part of the human trapezius, G., 373; Q., I, 187; acromio-cucullaire, S.-D., A, ll, 333; portion cervicale du trapéze, Ch., A, 216, and Fig. 90; cervicul trapezius, Ch. (Fl), A, 303; anterior part of the trapezius, Miv., B, 137. Figures.—Ectal aspect (66) ; ental aspect and insertion (67); insertion area (44). General Description.—Thin ; sub-trapezoidal ; from the dorsi- meson, in the caudal part of the cervical region and sometimes also the cephalic part of the thoracic, to the metacromion, and the adja- cent surface of the M. spino-trapezius. Dissection.—The caudal border has been indicated in describing the spino-trapezius, which is often slightly overlapped by it. It nearly coincides with a line drawn between the vertebral ends of the two mesoscapule. Lift it at the vertebral border of the scapula, and note that, 8-10 mm. from the meson, it becomes a thin tendon which may be traced across the meson to its platetrope without severing any definite attachments to the subjacent parts. Ventrad it may be traced to a point about 1 cm. caudad of the mesoscapula, and 1.5 to 2 cm: from the nearest part of the vertebral border of the scapula where it terminates upon the ectal surface of the spino- trapezius. The cephalic border of the muscle may be recognized as forming the caudal margin of a narrow intermuscular interval, the hiatus trapezti, at the side of the neck, about midway between the convex- ity of the shoulder and the meson. This interval is filled with con- nective tissue and fat, in which are imbedded a lymphatic gland and an artery. Follow this border to the meson, noting that, for about 1 cm. therefrom, it is either continuous with the caudal border of the next muscle (clavo-trapezius) or slightly overlapped by it. They may be separated, however, without cutting fibers. Ventrad of the hia- tus this border is usually overlapped for 3-5 mm. by the levator clavicule, the border of which must be lifted with care. Transect the acromio-trapezius at the vertebral border of the scapula. § 614, Origin.—In two or three parts: Inthe caudal five eighths the thin tendon is continuous across the meson with its platetrope, M, ACROMIO-TRAPEZIUS. 215 and is connected with the subjacent parts only by small nerves and vessels. It thus spans the interval between the vertebral borders of the scapula, which project slightly dorsad of the intervening verte- bral region. In the next two or three eighths the median raphé of the tendon is joined by a low median fascia which springs from the supraspinous ligaments. Sometimes, in the cephalic eighth, the muscular fibers reach the meson. The line of origin extends from the caudal end of the axial spine to some point between the Ist and 4th thoracic spines, thus filling the interval between the spino- trapezius and clavo-trapezius. Insertion.—In three parts: (A) the cephalic fifth is attached to the ectal surface of the metacromion (Fig. 44), and is usually over- lapped by the dorsal border of the levator clavicule ; (B) the cau- dal fourth or fifth is attached to the ectal surface of the spino- trapezius, along a dorso-caudal line forming an angle of 30-45 degrees with the mesoscapula ; (C) the intervening portion of the muscle is inserted upon the glenoid border of the mesoscapula. Remark.—The most notable feature of this muscle is the wide tendon of origin, which with its platetrope forms a heart-shaped area with its apex directed cephalad. The office of the muscle seems to be mainly that of a ligament, to prevent the separation of the vertebral borders of the scapule. M. CLAVO-TRAPEZIUS. § 615. Synonymy.—The cephalic or clavicular portion of the human trapezius, G., A, 873; Q., A, I, 187; clavo-cucullaire, 8.-D., A, II, 3382; part of the “ portion antérieure du mastoido-huméral,” Ch., A, 209; part of the anterior or superior portion of the mastoido- humeralis, Ch. (Fl.), A, 197; cephalic part of the “cephalo-humeral,” Miv., B, 147, and Wood, 9, 101, Fig. 23, “¢.” Itis thought by some that this muscle does not represent any part of the human trapezius. Figures.—Ectal aspect (66); ental aspect of reflected ends (67) ; clavicular end (72). General Description.—aA wide teeniate muscle, from the occiput and the cephalic part of the dorsimeson to the clavicle and the trapezio-deltoid raphé. Dissection.—The larger part of the cephalic border of the hiatus mentioned under the dissection of the acromio-trapezius is formed by the caudal border of the clavo-trapezius. Trace this border dorsad, bearing in mind its close union with the cephalic border of the acromio-trapezius. Then trace it ventrad, using great care in lifting it from the subjacent levator clavicule, and noting that, ven- 216 ANATOMICAL TECHNOLOGY. trad of the point of crossing, the interval between the two muscles is filled with a fascia so dense as to practically unite them. Lift the skin from 1-2 cm. along the occipito-presternal line. Dissect up the caudal border of the elavo-trapezius for 2-3 cm. at the junction of its dorsal and middle thirds, and pull it caudad. This may serve to indicate the position of the ventro-cephalic bor- der near the cut edge of the skin. Moreover, between the border of the clavo-lrapezius and the caudal border of the adjacent sterno- mastoideus, just caudad of the ear, will be seen emerging one or two nerves. Follow the border of the clavo-trapezius to the crista lambdoi- dalis, noting that, for 15-20 mm. therefrom, it is closely united with the caudal border of the adjacent sterno-mastoideus. The two muscles may usually be separated without cutting fibers, but some- times a slender fasciculus passes from one to the other obliquely at about the middle of their length. Part of the occipital end of the muscle is covered by a small tri- angular muscle belonging to the ear. This, the AZ cervico-auricu- laris (subcervico-pavilien of Straus-Durckheim, A, I, 194), is shown in Fig. 66, but not named ; it must be removed with great care to a point just cephalad of the crista lambdoidalis. Trace the ventro- cephalic border of the clavo-trapezius to the clavicle, which may be felt in the muscles between the presternum and the convexity of the shoulder. Transect the muscle at its middle; in reflecting the ventral end of the muscle, use great care in separating it from the subjacent clavo-mastoideus, which is also attached to the clavicle. After reflecting the dorsal part, divide it lengthwise along a line corre- sponding with the angle formed by the meson with the crista lambdoi- dalis ; the wider of the strips so formed may then be reflected across the meson, and the narrower upon the head, as shown in Fig. 67. § 616. Origin.—In two parts: (A) by a thin tendon 5-10 mm. long, from the mesal 10-15 mm. of the crista lambdoidalis; (B) by fleshy fibers from the supraspinous ligament for 4-5 em. from the crest to the caudal end of the axial neural spine (Fig. 30, §§ 208, 471). Insertion.—The details of the insertion differ considerably in individuals, and perhaps in the same individual according to age and the development of the clavicle. Sometimes the sternal end of the clavicle projects about 1 mm. mesad of the I. clavo-trapezius, M. OCCIPITO-SCAPULARIS. 217 while in other cases the muscle extends mesad of the bone so as te join the border of the ectopectoralis. Pull the muscle dorso-cephalad, and note its apparent continua- tion across the clavicle with the clavo-deltoideus. The muscles, however, are joined by a raphé, the ¢rapezio-deltoid, which is more apparent upon the ental aspect. Most of the clavo-trapezius is inserted upon this raphé ; but the ental fibers of the cephalo-ventral third or fourth are attached directly to the ventral border of the sternal and straighter half of the clavicle. Variations in the mode of insertion should be noted, drawn and reported. M. OCCIPITO-SCAPULARIS. § 617. Synonymy.—There seems to be some doubt as to its human homologue ; rhom- boideus capitis, Miv., B, 145, and Wood, 9, 92, Fig 28, ‘‘d”; occipito-scupulaire, 8.-D., A, II, 881; part of rhomboide, Ch., A, 202 ; part of rhomboideus, Ch. (F1.), A, 188. Figures.—Slightly at the dorsal end of the hiatus trapezii (66); ectal aspect (67); lateral border (73) ; insertion area (45), Exposure.—by the removal of the MM. acromio- and clavo- trapezius. General Description.—Narrow, teniate, near—and nearly par- allel with—the dorsimeson, from the crista lambdoidalis to the coraco-vertebral angle of the scapula. Dissection.— A bout midway between the occiput and the scapula the lateral border of the muscle appears as a slightly raised line 10-15 mm. from the meson. Trace it nearly to the occiput. Lateri- duct the middle of the cephalic half of the muscle so as to indicate its mesal border ; then transect. § 618. Origin.—By fleshy fibers from the crista lambdoidalis, entad of the origin of the clavo-trapezius, beginning 5-10 mm. from the meson, and extending 12-15 mm. laterad to a point nearly in line with the temporo-parietal suture (§ 493), where it is overlapped by the dorsal border of the sferno-mastoideus. Caudad, the mus- cle gradually approaches the lateral border of the rhomboideus. At the junction of the third with the last fourth, the muscle narrows and thickens, so as to become prismatic rather than teeniate. Insertion.—The narrowing muscle is wedged pretty closely between the rhomboideus at its mesal side and the levator anguli scapule at its lateral side, and is inserted either between these mus- cles upon the coraco-vertebral angle of the scapula (Fig. 45), 6-16 mm. cephalad of the mesoscapula, or upon the ental surface of the 215 ANATOMICAL TECHNOLOGY. second muscle close to its own insertion; in some cases, these two forms of attachment coexist. § 619. Explanation of Fig. 67.—The second layer of skeletal muscles of the left shoulder and neck. Preparation.—After the reflection of the skin and derma! mus- cles as in Fig. 66, the following muscles were transected and re- flected: spino-trapezius, acromio-trapezius, clavo-trapezius and Fic. 67.—Ta Seconp LAYER OF SKELETAL MoscLEs OF THE NECK AND SHOULDER, levator clavicule. The skin was also removed from the left side of the head, together with the external ear, the parotid and submaxil- lary salivary glands, and parts of the II. temporalis and masseter. Bones.— Acromion (§ 392).—This process of the mesoscapula is seen to afford origin to the acromio-deltoideus. Clavicula ($§ 422, 608).—By the reflection of the clavo-trapezius and the deflection of the clavo-mastotdeus, the clavicle is brought into view. Its name is connected with its sternal end. M. RUOMBOIDETS. 219 Crista lambdoidalis—The lambdoid ridge of the skull (Fig. 56)—The crest itself does not distinctly appear, but its position coincides with the lines of attachment of the occipito- scapularis and sterno-mastoideus and part of the clavo-trapezius. Mesoscapula and metacromion (Fig. 44 and § 608). Trochiter—The larger or cephalic tuberosity of the humerus (Fig. 30 and 74, § 420). Zygoma—The zygomatic arch (Fig. 30, 56, $8 207, 229).—The outlines of this promi- nent bony arch are shown just dorsad of the name. Muscles.—The acromio-deltoideus (§ 670), dermo-humeralis (§ 629), spino-deltoideus (§ 674), teres (§ 680), and triceps (§¥ 682, 684), are sufficiently described in the explanation of Fig. 66 (§ 608), and the supraspinatus, infraspinatus and teres (the word major is super- fluous) in the explanation of Fig. 74 (§ 672). The masseter, temporalis, splenius and digastricus are not particularly described in this work. Acromio-trapezius (Fig. 66, § 613).—This was transected so as to leave the semicordate tendon wholly in the vertebral part, which is reflected dorsad. The scapular part is slightly lifted so as to show the manner of its connection with the ectal surface of the spino-trapezius. Clavo-trapezius (Fig. 66, § 615).—The clavicular end has been reflected. The other and much wider end was longitudinally divided from the angle between the cephalic and mesal parts of the origin, and the two portions thus formed were reflected respectively cephalad and dorsad. The name is written upon the latter only. Latissimus (Fig. 66, § 635).—By the removal of the vertebral end of the spino-trapezius, the dorso-cephalic angle of this muscle is exposed. In the interval between its cephalic border and the caudal border of the rhomboideus, are seen some of the proper vertebral muscles. By inadvertence, the fibers in the dorso-cephalic corner are not represented as parallel with the border. Levator angult scapule (Fig. 73, § 686).—A part of the ectal aspect is seen between the splenius and the supraspinatus. The ental aspect of the whole muscle appears in Fig. 73. Levator clavicule (§ 627).—This has been transected near its insertion upon the meta- cromion, and the metacromial end is somewhat indistinctly seen reflected upon the spino- deltoideus. : Oceipito-scapularis (§ 617).—The cephalic attachment is seen to have been covered by that of the clavo-trapezius, and its scapular end is wedged in between the rhomboideus and the levator anguli scapule. Rhomboideus (§ 620).—The cephalic border is not satisfactorily represented in this figure. The scapular end of the muscle is better shown in Fig. 74. Spino-trapezius (Fig. 66, § 611)—The vertebral end has been removed altogether. The scapular end is lifted a little so as to show its relations with the acromio-trapezius and with the ectal aspects of the supraspinatus, infraspinatus and spino-deltoideus. Sterno-mastoideus (Fig. 72, § 622).—The removal of the clavo-trapezius, the salivary glands and the external ear has exposed its cranial attachment and its intersection with the clavo- mastoideus. Its sternal end and its connection with its platetrope are shown in Fig. 72. Other Parts.—Mt. au. ev.—Meatus auditorius externus.—Its lumen is exposed by the removal of the concha or external ear with the skin. M. RHOMBOIDEUS. § 620. Synonymy.—The human rhomboideus major, with probably the 7. minor also, G., A, 875 ; Q., A, 191; rhomboide, S.-D., A, II, 334 ; rhomboide, Ch., A, 202; rhomboideus, Ch. (Fl.), A, 188; rhomboideus major, Miv., B, 145. Figures.—Ectal aspect (67); scapular end, ectal aspect (74); scapular end, ental aspect (75); insertion area (44, 45). 220 ANATOMICAL TECHNOLOGY. General Description.—Trapezoidal in outline ; from the caudal part of the cervical dorsimeson and the cephalic part of the tho- racic, to the vertebral border of the scapula. Exposure.—By the removal of the MMW. spino- and acromio- trapezius. Posture.—Ventricumbent, with one or two blocks lengthwise under the thorax so as to permit the ventriduction of the shoulder. Usually the body must be steadied by cords or chain-hooks. Lat- eriduct the vertebral border of the scapula so as to render the IZ. - rhomboideus tense. Dissection.—The ventro-cephalic border of the muscle has been exposed by the reflection of the occipito-scapularis. The caudal border may be seen along a line running nearly laterad from the 4th or 5th thoracic spine, opposite the gleno-vertebral angle of the scapula. Note that the texture of the muscle is looser than that of the ¢rapezii, and that the caudal border is thinner than the ventro- cephalic, excepting the dorso-cephalic third of the latter. This muscle may be safely transected by cutting ecto-entad ; in reflecting it, note that the thickest part is opposite the 1st and 2d thoracic spines. § 621. Origin.—In two parts: (A) from the caudal two or three fifths of the cervical supraspinous ligament; in the latter case it includes the caudal two thirds of the axial spine, and thus extends about 1 cm. cephalad of the acromio-trapezius ; (B) from the sides of the tips of the first four thoracic spines and from the interspinous ligaments caudad of each of them, excepting, sometimes, the 4th. Insertion.— At least two forms of insertion are found. The sim- pler is as follows (Fig. 44, 45): the cephalic three fourths is attached by short tendinous fibers along the vertebral border of the scapula, passing gradually from its ental to its ectal margin. The cephalic half or third of this portion is closely united with the insertion of the levator anguli scapule. The caudal fourth is attached by fleshy fibers upon the gleno-vertebral angle in apposition with the origin of the teres. The other mode of insertion presents four divisions: (A) the cephalic 8 mm. is attached by fleshy fibers to the ental aspect of the lev. ang. scap. close to its insertion upon the ental margin of the vertebral border of the scapula, and caudo-ventrad of the insertion of the occipito-scapularis ; (B) the next 6-8 mm., constituting the thickest part of the muscle, is attached by fleshy fibers to the ental M. STERNO-MASTOIDEUS. 2o1 margin of the vertebral border, opposite the triangular space at the vertebral end of the mesoscapula; (C) the next 2-2.3 em. is at- tached by a thin tendon, 2-3 mm. long, upon the ectal margin of the vertebral border from opposite the middle of the space just men- tioned, and thus slightly overlapping part B, to within 8-10 mm. of the gleno-vertebral angle of the scapula; (D) the caudal 5-6 wm. is separated from the rest by an interval 1-5 mm. wide, and is in- serted by fleshy or very short tendinous fibers upon the ectal aspect of the gleno-vertebral angle in apposition with the origin of the teres. The scapular end of the muscle may be separated more or less readily into four divisions corresponding with the parts of the insertion just described, and the caudal division is sometimes quite distinct, with a decided extension toward the Zeres. M. STERNO-MASTOIDEUS. Remark.—This is strictly a muscle of the neck, but is here described on account of its close relations with the muscles of the shoulder and with blood-vessels. § 622. Synonymy.—The sternal part of the human sterno-cleido-mastvid, G., A, 857; Q., A, 1, 292; sterno-mastoidien, 3.-D., A, I], 248; sterno-mawillaire, Ch., A, 210; sterno- maaillaris, Ch. (Fl), A, 198; sterno-mastoid, Miv., B, 134. Figures.—Lateral aspect of cephalic half (66); lateral aspect (67); united sternal por- tions (72) ; sternal portion (73). § 623. General Description.—Teniate, along the ventro-cephalic border of the clavo-trapezius, from the presternum to the mastoid process of the temporal bone and the ventral part of the crista lambdoidalis. Posture.—Latericumbent ; a block transversely under the neck ; the head hanging. Exposure.—Connect the angle of the mouth with the occipito- presternal line (§ 610) by an incision corresponding with the direction of the margin of the upper lip. Note that the skin of the cheek, especially in old males, is very thick. Dissect up both edges of the skin for about 1 cm. The zygoma (Fig. 30, 56, 67) may be felt as a firm bony arch between the JZ temporalis (Fig. 67) dorsad, and the Jf masseter ventrad. Just caudad of the zygoma may be felt the cartilaginous meatus auditorius (Fig. 67, Mt. au. ex.), partly embraced “by the small, pale and rather I6oa6-fexinired parotid gland (Fig. 87, 107). Divide the meatus close to the head, and reflect the flap, together with the 222 ANATOMICAL TECHNOLOGY. ear and parotid, for 2-3 cm., taking care not to cut caudad of the crista. Then reflect the ventral flap for about the same distance. In the depression just caudad of the mandibular angle note the firmer tex- tured and darker colored submazillary gland (Fig. 66, 87). Its dorsal border is often quite firmly attached to the ventral border and ectal surface of the sterno-mastoideus. Remove the gland, together with the dense connective tissue in the groove between the head and the neck ventrad of the origin of the occipito-scapularis. Along the ventral border of the space occupied by the submax- ilary gland is the Vena jugularis (Fig. 101), which lies upon the ectal aspect of the sterno-mastoideus, crossing very obliquely from its ventral to its dorsal border. Divide the vein at the middle of its length, reflect the ends and free the surface of the muscle from fat and connective tissue. Dissection.—The dorsal border of the muscle is apparent at about its middle, where it was crossed by the V. jugularis, and where it in turn crosses the ventral border of the subjacent clavo- mastoideus. Lift this border, taking care not to include the fibers of the clavo-mastoideus.