THE HUMAN SPECIES THE HUMAN SPECIES CONSIDERED FROM THE STANDPOINTS OF COMPARATIVE ANATOMY, PHYSIOLOGY, PATHOLOGY AND BACTERIOLOGY BY LUDWIG HOPF AUTHORISED ENGLISH EDITION WITH 2l6 ILLUSTRATIONS AND ^ PLATES LONGMANS, GREEN, AND CO. 39 PATERNOSTER ROW, LONDON NEW YORK, BOMBAY, AND CALCUTTA 1 909 AUTHOR'S PREFACE. WHENEVER the question as to the essential nature of Man is raised the uninitiated seem to think that there is nothing easier to answer. To them not only all that concerns the body, but also man's soul, is something so long since settled, so self-evident, as to require no further discussion. On the other hand, however, ever since the establishment of anthropology as an inde- pendent science, with untiring diligence experts have been busy investigating the nature of Man as compared with that of the lower animals, and now not a year passes without these investigations resulting in distinct modifications of the accepted points of view, in one or other direction. The aim of this book is the comparison of the essential characteristics of Man with those of the lower animals in the light of the results of recent research. Many a character hitherto regarded as distinctively human will be found to be shared by the lower animals, many another be proved man's indisputable possession, though here and there he may not be particularly edified thereby. To arrive at a clear understanding of the nature of Man the parallels drawn between him and the animal world must not be confined to anatomy and physiology only, but extended, in a rigidly critical spirit, vi PREFACE to psychology and pathology, for psychology is but the physiology of the soul, and pathology the doctrine of life under changed circumstances. THE AUTHOR. STUTTGART, July, 1907. PREFACE. IN his work on the " Human Species," Hopf compares the structure, functions and diseases of man with those of animals. It must not be taken, however, that the volume is simply a collection of facts and details. A glance at the headlines of the pages will reveal the wide extent of the ground covered. After discussing the distribution of mankind, the ancestors of man, the struc- ture and functions of the various tissues, Hopf deals with such interesting questions as psychology, the origin of the mind, emotions and their expression, social customs, marriage, communism, modesty, shame, religion and art. He then proceeds to consider the diseases of man and animals, the parasites common or peculiar to each, .and concludes with a fascinating chapter on self- help in animals and primitive man. Realising that such aspects of the subject will appeal to the general reader, the text has been shorn of scientific terminology as much as possible. In preparing an English translation the Editor has tried to follow out the general idea of the author, and therefore no apology is needed for the terminology employed. Difficulties have arisen in adapting the German classification to the English reader, and in some instances it has been necessary to retain terms and distinctions not usually current in English books. A vii viii PREFACE few alterations and additions have been made, but these in no way affect the deductions, theories or views of the German author. Wherever possible, German quotations from English works have been verified, and the original English wording cited. There is little doubt but that those who study this work will find in it a fund of information presented in an interesting, though concise, manner. W. H. 1909. CONTENTS. PART I. PAGE INTRODUCTION AND GENERAL CONSIDERATIONS i DISTRIBUTION OF MANKIND 19 DOES MANKIND CONSIST OF ONE OR OF SEVERAL SPECIES ? . . .24 THE ANCESTORS OF MAN . . .26 VIEWS OF BRANCO 26 „ „ DUBOIS 27 „ „ SCHLOSSER 27 „ „ RHUMBLER 28 „ „ MORRIS 28 „ „ COPE 28 „ „ KLAATSCH 29 FOSSIL APES 29 TERTIARY MAN . -33 STATURE OF TERTIARY MAN . . • 36 BIRTHPLACE OF TERTIARY MAN 37 QUATERNARY MAN ........... 39 TRANSITION FROM THE PALEOLITHIC TO THE NEOLITHIC PERIOD . 46 NEOLITHIC MAN 49 PART II. A. COMPARATIVE ANATOMY AND HISTOLOGY 52 I. BONES 52 SKULL 53 VERTEBRAL COLUMN 66 THORAX 69 BREAST BONE, COLLAR BONE AND SHOULDERS .... 70 PELVIS 72 ABSENCE OF TAIL 73 EXTREMITIES 75 II. MUSCULAR SYSTEM 83 III. SKIN, HAIR, NAILS, PIGMENTATION, GLANDS 95 IV. HEART AND VESSELS 107 SPLEEN, LYMPH GLANDS . . 112 BLOOD-CELLS . . . 112 x CONTENTS PAGE V. RESPIRATORY SYSTEM 113 VI. DIGESTIVE SYSTEM 118 MOUTH 122 GLANDS 124 (ESOPHAGUS AND STOMACH 125 INTESTINE 128 APPENDIX 130 LIVER AND PANCREAS 131 VII. KIDNEYS, BLADDER 134 ORGANS OF GENERATION ........ 140 VIII. NERVOUS SYSTEM 149 BRAIN 152 CEREBRAL NERVES 167 WEIGHTS OF BRAIN 168 SYMPATHETIC SYSTEM 171 IX. THE SENSES 171 1. TOUCH 171 2. SIGHT 174 3. SMELL 178 4. TASTE 180 5. HEARING 183 B. COMPARATIVE PHYSIOLOGY AND PSYCHOLOGY 189 GENERAL PHYSIOLOGY 189 I. SKELETON AND MUSCLES 192 SUPERIORITY OF ERECT POSITION 193 II. SKIN AND APPENDAGES 199 PERSPIRATION 199 FAT SECRETION 200 ODOUR ........... 201 TRANSPIRATION 202 POWER OF MOVING SKIN 202 III. HEART AND VESSELS 203 HEART BEAT 204 BLOOD PRESSURE 204 VOLUME OF BLOOD 205 PROPERTIES OF BLOOD 205 IV. RESPIRATORY SYSTEM 209 TEMPERATURES 212 V. DIGESTIVE SYSTEM 214 LIVER AND ITS ACTIONS 218 VI. URINOGENITAL SYSTEM ........ 221 URINARY ORGANS 221 REPRODUCTIVE ORGANS 222 PUBERTY 222 MENSTRUATION 223 CONCEPTION AND FORMATION OF EMBRYO . . . 229 PREGNANCY 230 INFANCY 231 CONTENTS xi PAGE VII. NERVOUS SYSTEM 232 VIII. CRANIAL NERVES AND SENSE-ORGANS 238 SMELL ........... 238 VISION 241 HEARING 248 TASTE 251 TACTILE AND TEMPERATURE SENSE 252 PSYCHOLOGY 256 WHERE is THE ABODE OF THE MIND ? ..... 256 THE DUALISM BETWEEN MIND AND LIFE 257 WHAT is THE RELATION OF THE HUMAN TO. THE BRUTE MIND? 259 SPECIAL COMPARATIVE PSYCHOLOGY 266 IDEATION ........... 267 MEMORY 268 DELIBERATION, JUDGMENT, REASON . . . . . . 270 CURIOSITY 271 COUNTING, RECKONING, MEASURING, WEIGHING .... 272 SPEECH 275 EMOTIONS AND THEIR EXPRESSION ....... 282 LAUGHTER 283 DISPLEASURE, SORROW, FRIGHT, PAIN . . . . 284 SOBBING, KISSING 286 GRIEF, ENVY, JEALOUSY 287 ANGER 288 WILL, IMPULSES 290 SOCIAL CONDITIONS AND OBSERVANCES 295 COMPANIONSHIP, FRIENDSHIP 295 MARRIAGE, MONOGAMY, POLYANDRY 297 COMMUNAL MARRIAGE AND TOTEMISM 299 FAMILY AND HOUSEHOLD LIFE 301 PATRIOTISM 302 MIGRATION IMPULSES 302 COMMUNISM 304 PARENTAL FEELINGS 305 GRATITUDE, TRUST 306 SENSE OF SHAME 307 RELIGION 308 TOTEMISM 308 ANIMISM 309 IDOLS 311 ARTS AND HANDICRAFTS . 313 FIRE . . . 313 STONE WEAPONS AND TOOLS 317 NAVIGATION . . . 337 DOMESTIC ANIMALS . . 339 FIELDS AND GARDENS 342 SALT . . -345 SENSE OF BEAUTY AND ADORNMENTS 346 xii CONTENTS PAGE PAINTING 349 PALAEOLITHIC ART 350 NEOLITHIC ART 352 IRON AND BRONZE PERIODS 353 Music 355 SINGING 356 MUSICAL INSTRUMENTS 361 WRITING 362 PSYCHOLOGICAL RETROSPECT AND FORECAST 370 C. COMPARATIVE PATHOLOGY AND PATHOLOGICAL ANATOMY . . . 375 I. GENERAL PATHOLOGY. INFLAMMATION, ETC. .... 375 GIANTS AND DWARFS 378 DEFORMITIES 381 HERMAPHRODITES 383 SEXUAL CHARACTERISTICS ........ 383 II. SPECIAL PATHOLOGY 390 1. INFECTIOUS DISEASES 390 CHOLERA .......... 390 ENTERIC FEVER 391 TUBERCULOSIS 391 LEPROSY 392 DIPHTHERIA 392 TETANUS 393 INFLUENZA .......... 393 WHOOPING COUGH 393 RELAPSING FEVER 393 PNEUMONIA 394 Pus 394 MALTA FEVER 394 ACUTE RHEUMATISM ........ 394 MENINGITIS 394 DYSENTERY 395 VENEREAL DISEASES ........ 395 SCARLET FEVER, MEASLES, ETC. 396 ANTHRAX, GLANDERS, ETC 397 RABIES, FOOT-AND-MOUTH DISEASE 397 PSITTACOSIS 397 ACTINOMYCOSIS 397 MALARIA 398 YELLOW FEVER AND PLAGUE 399 CANCER 399 2. NON-INFECTIOUS DISEASES 401 PARASITES 401 INTOXICATIONS 404 DISEASES OF DIGESTIVE ORGANS 407 DISEASES OF RESPIRATORY ORGANS 408 DISEASES OF GENITO-URINARY ORGANS 409 DISEASES OF MUSCULAR SYSTEM 411 CONTENTS xiii PAGE DISEASES OF NERVOUS SYSTEM 411 DISEASES OF THE SKIN 417 SURGICAL CONDITIONS OF THE DIGESTIVE, RESPIRATORY, GENITO-URINARY, AND NERVOUS SYSTEMS . . . 418 DISEASES OF THE EYE 426 DISEASES OF PREGNANCY 429 DISEASES ASSOCIATED WITH LABOUR ..... 433 APPENDIX — COMPARATIVE THERAPEUTICS 443 SELF-HELP IN ANIMALS 444 CARE OF WOUNDED 447 OBSTETRICS 449 MEDICAL ART IN EGYPT, GREECE, ALEXANDRIA, ROME, ETC. . . 450 LIST OF ILLUSTRATIONS. FULL PAGE ILLUSTRATIONS. PLATE FACING PAGE I. Upper molars of Tertiary apes, later anthropoids and Hottentots. (Wiirtt. Jdhreshefte des Vereins fur vaterl. Naturkunde, 54 Jahrg., Tafel i.) 64 II. Lower molars of Tertiary apes, later anthropoids and of man. (WUrtt. Jahreshefte des Vereins fur vaterl. Naturkunde, 54 Jahrg., Tafel ii.) 64 III. Brains of mammals and of man 156 IV. Deformities. (Ranke, Der Mensch) 386 V. Bacteria, cocci and amoeba primarily pathogenic for man. (Lehmann and Neumann's Atlas) 394 VA. Bacteria, cocci and amoeba primarily pathogenic for man. (Lehmann and Neumann's Atlas') . . . 394 VI. Specific internal parasites of man 402 V!A. Specific internal parasites of man 402 VII. Specific internal parasites of man 402 ILLUSTRATIONS IN THE TEXT. FIG. PAGE 1. a, Mesopithecus Pentelloi; b, Skull of a gorilla. (Homes, Urg. d. M.) 31 2. Restored skull of the Pithecanthropus erectus. (Dubois) . . . 32 3. Transverse section of the Hohlefels in Aachtal (Swabia). (Homes) . 44 4. Red painted pebbles from Mas d'Azil. (Homes) .... 47 5. Shell-heap at Magern (Portugal) showing the exhumed skeletons. (Homes) 49 6. A pile-dwelling. (After Prof. Haberlin) 50 7. Transverse section of the metacarpal bone. (From Thome', Zoologie) 52 8. Human skeleton 54 9-12. Skulls of anthropoids and of the lower races of man. (From the Corresp.-Blatt f. Anthrop., Ethnol. und Urgesch., 1877) . . 55 13. Skull of a newly born Orang. (From Selenka) 56 14. Skull of a human embyro often months. (From Selenka) . . .56 15. Dolichocephalous skull viewed from the side. (From the Corr.-Blatt f. Anthrop., etc., 1883) 57 xvi LIST OF ILLUSTRATIONS 16. Human palate with intermaxillary bones. (Ranke) .... 59 17. Development of the Human embryo. (Haeckel, Anthropogenic) . 62 18. Development of the Gibbon embryo. (Haeckel, Anthropogenic) . 62 ig. Gorilla foetus of the size of a human foetus of one to one and a half months. (Duckworth) 63 20. Human teeth ........... 64 21. Human vertebral column in erect position viewed from the right side. (H. Meyer) 67 22. Episterpheus (front view) 68 23. Fifth cervical vertebra (viewed from underneath) .... 68 24. Human thorax 69 25-31. Collection of scapulae. (Ranke) ....... 71 32. Male pelvis. (Ranke, Der Mensch) 73 33. Female pelvis. (Ranke, Der Mensch) 73 34. Arm and hand of three anthropoids. (From Haeckel, Anthropogenic] 76 35. Human skeleton. (From Haeckel, Anthropogenic) .... 79 36. Skeleton of a gorilla. (From Haeckel, A nthropogenie) ... 79 37. Muscles of the head and neck. (Thome) ...... 85 38. Rudimentary muscles of the human ear. (Haeckel) .... 85 39. Muscles of the human axilla (thorax from the side). (Ludwig Tobler, The Fascia Axillaris of Man) 86 40. Anterior muscles of the human neck. (Heitzmann-Zuckerkandl) . 87 41. M. rectus abdominis. (Heitzmann-Zuckerkandl) .... 88 42. Muscles of the trunk and lower extremities. (Thome) ... 90 43. Facial muscles of mimicry. (Henle) 91 44. Muscles of the human thumb and fifth finger. (Heitzmann-Zucker- kandl) 92 45. Muscles of arm and hand, front aspect. (Thome, Zoologie) . . 93 46. Muscles of trunk, etc., back aspect. (Thome, Zoologie) ... 94 47. Posterior muscles of the thigh. (Heitzmann-Zuckerkandl) . . 95 48. Muscles of human calf. (Heitzmann-Zuckerkandl) .... 96 49. Section of skin of finger tip. (Thome', Zoologie) . . . -97 50. Transverse sections of hair (magn.). (Waldeyer) .... 98 51. Russian hairy man. (Ranke, Der Mensch) ...... 99 52. Julia Pastrana. (Haeckel, Anthropogenic} 99 53. Pithecia satanas. (Brehm, Tierleben) 100 54. Sinus hairs of the Norway rat. (Thome', Zoologie) .... 102 55. Inguinal skin of a European woman, blonde, thirty-eight years. (Adachi) 104 56. Trunk of a girl of Vista. (Hartmann) 106 57. Circulatory system of man. (Thome, Zoologie) .... 109 58. Human spleen. (Ranke, Der Mensch) 112 59. Lymph cells 113 60. White blood corpuscles, mobile and immobile. (Ranke) . . .113 61. Red corpuscles of human blood. (Kolliker, Gewebelehre) . . . 113 62. Adult male oran-utan (throat sac) 116 63. Anterior section of larynx viewed from within. (Thome, Zoologie) . 116 64. Heart, large circulatory trunks and lungs. (Thome', Zoologie) . . 117 65. Terminal ramifications of the bronchial tubes with the air-cells. (Thom£, Zoologie) 118 66. Mouth, palate and pharynx. (Thome, Zoologie) .... 122 LIST OF ILLUSTRATIONS xvii FIG. PAGE 67. Human tongue. (Thome, Zoologie) 123 68. Liver, stomach, spleen and pancreas (liver and stomach laid open). (Ranke, Der Mensch) 126 69-71. Gastric glands of man. (Oppel, Part I.) 127 72. Inferior surface of the liver. (Ranke, Der Mensch) .... 132 V73. A portion of the liver. (Thome, Zoologie) 133 74. Liver cells. (Haeckel, Anthropogenic} 133 75. Wolffian bodies of the human embryo. (Kobelt) .... 137 76. Section of human kidney. (Ranke) 138 77. (i) Malpighian body of man. (2) 3 epithelial cells from convoluted canaliculi. (Kolliker, Gewebelehre) 138 78. Transverse section of medulla spinalis from the region of the back. (Thome, Zoologie) . . . . . . . . .151 79. Spinal cord ; front view. (Thome", Zoologie) 152 80. Nervous system of man 154 81. Median section of brain . . 157 82. Human brain viewed from beneath 161 83. Sagittal section of the parietal eye, parietal nerves and distal extremity of the epiphysis of an almost mature embryo of Hatteria punctata. (Oppel, Vergl. mikr. Anat., Part v., Fig. 83) .... 165 84. Epiphysis and surrounding parts of the skull of a child of twelve years. (Oppel, Vergl. mikr. Anat., Part v., Fig. 123) . . . 166 85. Touch-bulbs in the hand of the ape. (Kollmann) .... 173 86. Touch-bulbs in the human hand. (Hibert) 173 87. Diagrammatic section of the right eye. (Thome, Zoologie) . . 176 88. The eyeballs represented as lying imbedded in the orbital fat with the attachments of the oculomotor muscles. (From Thome, Zoologie) 177 89. Outer wall of right half of the nose. (From Thome, Zoologie) . . 179 90. Olfactory nerve-cells, highly magnified. (Thome, Zoologie) . . 180 91. Female nosed ape. (Haeckel, Anthropogenie) 181 92. Male nosed ape. (Haeckel, Anthropogenie) 181 93. (i) Circumvallate papillee ; (2) Individual taste-bud. (Highly magni- fied.) (Thome, Zoologie) 182 94. Human ear 186 95-96. Ape's ear. (Haeckel, Anthropogenie) ...... 187 97-98. Man's ear. (Haeckel, Anthropogenie) 187 99. Human ear ' 188 100. How a quadruped stands 192 101. How the bird stands 193 102. Man standing naturally. (Munk-Schultz) 194 103. Fore-legs of horse, stepping and supporting. (Munk-Schultz, Physio- logie) 196 104. Erect gait of gibbon • . . 197 105. Erect gait of orang-utan 197 106-107. How a man walks. (Munk-Schult/) 198 108. Aortic valves. (From Ranke) . . 203 109. Human respiratory movements. (Munk-Schultz) . . . .211 no. "Larynx in inspiration. (Munk-Schultz) ...... 212 in. Larynx during phonation. (Munk-Schultz) . . . . . 212 112. A ripe human Graafian follicle. (Haeckel) 224 xviii LIST OF ILLUSTRATIONS FIG. PAGE 113. The human ovum after issuing from the Graafian follicle, surrounded by the cells of the discus proligerns (in two radiating crowns). (Nagel) 224 114. Spermatozoa or spermia of various mammals 225 115. Fertilisation of a mammalian ovum by the spermatozoa. (Haeckel) . 226 116. Gastrula of primitive-gut animal or gastrasad ..... 227 117. Gastrula of amphioxus. (Haeckel, Anthropogenic) .... 227 118. Central nervous system of the human embryo at the beginning of the seventh week 229 119. Diagram of the complete olfactory tract. (Munk-Schultz) . . . 239 120. Diagram of the anterior portion of the eye. (Thome") . . . 242 121. Eye resting and accommodating (magnified five times), after Helmholtz. (Munk-Schultz, Physiologic) 243 122. Ophthalmoscopic appearance of human fundus 244 123. Ophthalmoscopic appearance of fundus of horse 245 124. Scheme of layers of the retina. (Ranke) 246 125. Portion of Corti's organ 250 126. Right reindeer's horn with notches 274 127. Girl laughing 283 128. Black baboon grinning ......... 283 129. Chimpanzee undeceived and annoyed. (Darwin, Expression of the Emotions) ........... 284 130. Expression of grief. (Darwin, Expression of the Emotions) . . 284 131. Boy crying. (Darwin, Expression of the Emotions) .... 285 132. Angry dog. (Darwin) , 288 133. Angry man. (Darwin) 288 134. Trepanned neolithic skull. (Homes, Urgeschichtc des Menschen) . 310 135. Grave in South Bulgaria . . . . . . . . .311 136. Ivory figure from the side. (Homes, Urgeschichte der Kunst) . . 312 137. Ivory figure, excavated at Briinn, £ natural size. (Homes, Urges- chichte der Kunst) . . . . . . . . . .312 138. Neolithic hollow clay figure, from Laibach Moor, £ natural size. (Homes, Urgeschichte der Kunst) ....... 313 139. Crescentic clay structure from a barrow near Oldenburg, £ natural size. (Homes) 314 140-42. Stone plaques from the civic monument in Skane. (Homes, Urges- chichte der Kunst) . . . . . . . . . -315 143. Carved flints, J natural size. (Homes) ...... 319 144. Flint knife of the La Madeleine type. (Homes) 320 145. Shoulder blade of reindeer with the needles which had been carved out of it. (Homes) 321 146. Lance-head from reindeer horn. (Homes} 321 147. Neolithic reniform axe-head made of stag's antlers. (Homes) . . 322 148. Neolithic polished stone axe-heads with holes for handles. (Homes) . 322 149. Stag's horn arrow-head, harpoon and hook from the pile-dwellings at Font (reduced). (Homes) 323 150-54. Weapons and implements of the Bronze Age (Hungary and Bohemia). (Homes) 324 155. Copper battle-axe from Servia. (Homes) 325 156. Objects found in the Swiss pile-dwellings of the Bronze Age. (H6rnes) 325 157. La Tene sword from Hallstatt. (Homes) 326 LIST OF ILLUSTRATIONS xix 158. Neolithic pottery from South-west Germany. (After Schiiz) . . 329 159. Neolithic pottery from South-west Germany. (Swabian Exploration Reports, VII.) 330 160. Plaited and woven work, spindles and spinning-wheels from the Swiss lake villages 332 161. Tree-dwelling from Southern India. (Homes) 334 162. House-urn from Alba Longa. Hallstatt period. (Homes) . . 336 163. Inflated goat's hide for a boat. (Cor.-Bl.f. Anthr., 1904) . . . 338 164. Tree canoe from the pile-dwellings in Lake of Biel .... 339 165. Skull of hound. (Robenhausen) 341 166. Skull of Bostaurus, var, primigenius ....... 341 167. Skull of a bog swine from Lattringen . 342 168. Mandible of bog swine from pile-buildings at Schaffis . . . '. 342 169. Goat-like sheep. (Graubiinden) 343 170. Cereals of the pile-builders • . 344 171. Bronze sickle from Dachingen (Wurtemburg). (Swabian Exploration Reports, IV.) 344 172. Handmill from South Sweden 345 173. The spotted bower bird (Chlamydera moculata). (Brehm) . . 347 174. Ornaments made of teeth and shells from La Madeleine. (Homes) . 348 175. Bronze ornament of the Hallstatt period, | natural size. (Homes) . 349 176. Back view of female torso in ivory from Brassempouy. (Palaeolithic, J natural size) 350 177. So-called sceptres with figures of animals. (Homes). . . . 351 178. Bisons. Frescoes from the wall of the grotto Font de Gaume (Dor- dogne). (Homes) j 352 179. Chafer. (After Landois) 359 180. Hind leg of Stenobothrus pratorum. (After Landois) . . . 360 181. Pipe of reindeer bone .......... 361 182. Clay drum from Ebendorf, near Magdeburg 361 183. Flute player of limestone from Keros, near Amorgos, £ natural size. (Homes) 362 184. Rod with marks scratched on it, made of reindeer-horn. (Homes) . 363 185. Flints, painted in red, from Mas d'Azil. (Homes) .... 364 186. One side of the hieroglyphics inscribed on the obelisk at Luxor. (Karpeles) 365 187. Example of a Chinese inscription of Yu. (Karpeles) .... 366 188. Example of the arrangement of the lines in an ancient Babylonian inscription. (Karpeles) ........ 367 189. Knotted cord from Hepatone, Tahuata, Marquesas Islands. (After v. d. Steinen) ^69 190. Knotted cord from Hepatone, Tahuata, Marquesas Islands. (After v. d. Steinen) 370 191. Giant tadpoles of Rana esculenta, \ natural size .... 378 192. A Bush pygmy. (After Fritoch) 37Q 193. Cretin. (Virchow) 380 194. Hare-lip. (Bardeleben) 382 195. Hen with cock's plumage ......... 385 196. Tail on a boy, six months old. (Granville Harrison) . . . 386 197. Supernumerary digits. (Ranke) 387 198. Supernumerary milk glands ........ 388 xx LIST OF ILLUSTRATIONS FIG. PAGE 199. Russian hairy man. (Ranke) 389 200. Julia Pastrana. (After Haeckel) 389 201. Flea 403 202. Human head-louse . 403 203. Crab-louse 4°3 204. Bed bug 403 205. Microsporon furfur 404 206. Oi'dium albicans 4°4 207. Sarcina ventriculi 4°4 208. Pes varus 425 209. Pes valgus 425 210. Pes equinus 425 211. Calcaneus 425 212. Robert's pelvis. (Spath) 439 213. Nasgele's pelvis. (Spath) 439 214. Osteomalacic pelvis. (Spath) 440 215. Pelvis in hip-joint disease. (Spath) 441 216. Contracted pelvis in lordosis. (Spath) 442 PART I. Introduction and General Considerations. WHEN we bear in mind the age of mankind as estimated by the geologist, the recognition of man's true place in Nature must seem a comparatively young, even modern, achievement. This fact is certainly very striking, but is easily explained by the circumstance that the question as to man's place in Nature is indissolubly bound up with the question of man's origin. Ever since there have existed on our planet thinking beings who have speculated as to the origin of the visible world, two conflicting dogmas have found currency. " The world was created," cried some ; " The world has grown," replied the others. Thus it is but natural that the same difference of opinion has prevailed from the earliest times on the subject of the origin of man. The belief in a Creator of the world, and of man, is found in its lowest form among certain savages, who hold the curious doctrine that not the Creator himself but certain animals, acting for him, created the world and man. According to the faith of the Savo Islanders (Solomon Isles) it is to the shark that we are indebted for the creation of the island, and of the men and the mound-birds who inhabit it. Among the tribes of America the idea of animal demiurges is strongly developed. They re- gard animals as symbols of the divine force in Nature, and as existing before the creation, and taking part in the production of the world and of man. The principal part, however, is played by a fabulous bird which is either a god itself or a revelation (abode) of the same. Certain western tribes of North America imagine the earth to have been created by a crow ; the people of Delaware and Florida venerate the stag as a powerful spirit and creator of the world and of man. Others, again, attribute the act to the hare, 7 2 THE HUMAN SPECIES the beaver, the otter, or the bear, but wherever the coyote appears it is to him that chief honour is paid, on account of his sagacity, and he is regarded as the creator ; indeed, in the Oregon region, where the language contains no special word for "deity," the "little wolf" — half animal, half higher being — is the chief object of veneration. On a considerably higher plane stand those tribes who attribute the creation of the world and of man to a mediator between God and man, in other words to a demiurge pos- sessing human attributes. All the nomadic tribes of the Polar regions, for instance, believe in a powerful benevolent deity who, however, is too sublime to conduct the work of creation personally, and has consequently entrusted it to his only son. The same fundamental idea is to be traced in the Javanese tradition, according to which there dwelt in the centre of the universe, long before the creation of heaven and earth, a deity named Sang-yang-Wisesa who gained permission from the supreme god to create heaven and earth, sun and moon, and finally man himself. This demiurge, Sang-yang-Wisesa, is identical with the Unkulunkulu of the Zulus of South-West Africa, with the Numank Machana of the Peruvian Indians, and with the demiurgic architect of the Aztecs, who first im- proved the form of the created world on its emerging from the deep, whereupon man, in his original state a formless mass of flesh and blood, was brought to perfection by Quetzalcoatl. Although among many American tribes the deity from whom man has descended is of an undeniably anthropomorphous nature, being himself the " First Man" among many others the idea of a demiurge in human form is clearly traceable. For instance, the Leni Lenape represent the first man, Nahabasch, as mediator between god and man ; the Caribbeans maintain that the first man, Loguo, descended from heaven and returned thither after creating the world and man ; finally, the Algon- quins' principal god, Menabogho, is sometimes represented as mediator between the supreme spirit and mankind, sometimes as the progenitor of the human race and creator of the second world, the first having been destroyed by evil spirits. We sometimes even find the first man regarded as the son of the supreme spirit ; for instance, among the Califor- INTRODUCTION AND GENERAL CONSIDERATIONS 3 nians, whose great god Cumango sent his son, the first man, Guaayayp, down to earth to perfect the state of imperfectly created man. Etalapass, the god of other western tribes of America, did, it is true, create men, but they were imperfect and incapable of movement till another god, Ecannin, had compassion on their helplessness and opened their mouth and eyes, bestowed the power of movement on hands and feet and taught them to make boats and nets. In the mythology of the maritime tribes of North America sagas tell of semi-human beings whose definite separation into man and beast only took place later through the intervention of the son of god during his wanderings on earth.1 Son of god and creator of the world is also Adam Kad- mon of the cabalistic book of Jezirah ; he proceeds from Ensoph, the highest of beings, as the first source of light ; thereupon ten Sephiroth, or spiritual powers, radiate from him and serve, in conjunction with the twenty-two numerically con- ceived consonants of the Hebrew alphabet, as the instruments of the creation of the world and man. The Gnostics again, whether they incline to the Greek or the Oriental version, are unanimous in attributing the material world, including man, not to the highest divine being, the Pleroma, but to an inferior creator, a demiurge, who is connected with the material world, and subordinate to the Pleroma. " Pleroma " signifies " fulness of Divine life ". Whether this idea of a demiurgic son of god be primary or, as Waitz and other anthropologists assume, secondary, of later date, it must certainly be deemed inferior to the conception of a single omnipotent creator. This type of creator is to be found, under the most varied forms, among the savage peoples of all parts of the world. Space does not permit us to attempt a complete enumeration of the names under which the creator appears, and the traditions of the creation of man therewith connected. But we must not overlook the remarkable sagas, current among certain tribes, which treat of the creation of woman as a distinct act of creative power. The Munda Kolhs, for instance, maintain that their god Singbonga only then pro- 1 A full account of North American mythology will be found in the Bureau of American Ethnology Bull. 30. I * 4 THE HUMAN SPECIES ceeded to create a girl when the first boy had been killed by a horse. In the tradition of the Andaman Islanders the first man created by Paluga was tall and blackbearded, and did not receive a wife until he had proved that he was capable of sup- porting himself; the Arawaks, a branch of the Caribbeans, are so lacking in chivalry as to assert that man was created by a good spirit, and woman by an evil one. The Eastern Eskimos also ascribe the creation of the world and man to two distinct deities : one good, bearing the masculine name of Tongarsak, the other malevolent and nameless, but it has not been proved that they impute the creation of woman to this latter. The contrast between a good and an evil creator is still more striking in the Zend-Avesta, the sacred writings of Zoro- aster, the philosopher of ancient Persia. Ormuzd, wishing to raise a bulwark against his enemy, Ahriman, created the material world with its living beings in 365 days, taking 75 days for the creation of man alone. This primitive being was bisexual, and from him descended the first pair, Meschia and Meschiana, the progenitors of the peoples of the earth. Ormuzd was, however, powerless to prevent man's ultimately falling a victim to the sinister god Ahriman (Death). Zoroaster's teaching represents man as created for his own sake, whereas, in the Indian doctrine of the revelation of Ekhumescha, according to the Sastra of Brahma, living organ- isms, including man, were created merely in order to serve as a purifying, intermediate stage for the fallen devetas (angels), the cow forming the last stage but one, and man the final. In all these legends man is simply a dynamic creation. The supreme being willed that he should be, and he was. In con- trast to this purely dynamic process of creation we have the conceptions of those nations who endeavour to explain the process on material mechanical grounds. Here too we find the most diverse ideas prevalent, for is it not inevitable that all speculation as to the creation of the world in which we live should be powerfully influenced by our surroundings, organic and inorganic? Hence it need not astonish us to learn that man is sometimes supposed to have originated in plants. For instance, the Leni Lenape think that the supreme spirit formed the first man and woman out of a tree- INTRODUCTION AND GENERAL CONSIDERATIONS 5 stump. According to the belief of the Sioux Indians, the first created men stood for several generations like tree-trunks, with their feet rooted in the ground, until a great snake gnawed through the roots and thus endowed man with the power of movement. The Caribbeans believe that their creator, Aluberi, seated himself on a tree and broke off twigs which he changed into animals ; but one he turned into a man, and the man fell asleep, and on awaking found a woman at his side. The Bagoba tribe, inhabiting South Mindanao, believe that the first plants were a bamboo and a betelnut palm, and that at the bidding of their god, Todlai, from the cleft bamboo there sprung a boy and from the palm a girl ; when they were grown up they married and became the parents of the human race. In other parts of the world the creator is supposed to have made man out of animals ; the Dieyeries, an Australian tribe, believe man originated from black lizards. The benevolent deity, Moora Moora, changed their feet to fingers and toes, added a nose to the face and, in order to preserve their equili- brium when standing erect, removed the tail, whereby they became lords over all other creatures. Nevertheless, traditions of man originating in plants or ani- mals are rare in comparison with the overwhelming majority of those wherein he has been created out of clay, earth, or stone. Traditions of this type are current among the Gallas of East Africa, the Javanese, the North American Indians, and, in very pronounced form, among the Semitic tribes of Further Asia, the Babylonians and the Hebrews, their followers in civilisation, and, in yet another more modified form, among the Mohammedans. The so-called Mosaic tradition of the creation handed down from the Babylonians, forms one of the most remarkable phenomena in the history of civilisation, for it not only consti- tutes a strict article of the Jewish faith but, from the founding of Christendom, has continued for over nineteen centuries to be the official explanation of the origin of man in all Christian churches and schools. The philosophic-theological speculation of scholasticism could do it no harm, for even after the early dialectical stage of scholasticism had given way to pure philo- sophy, the quintessence of the philosophy was, after all, only a confirmation of the belief in revelation. Thomas Aquinas, the 6 THE HUMAN SPECIES celebrated disciple of Albertus Magnus, remarks drily on this subject : " The beginning of the world (and of man) is not a matter of knowledge but of revelation ". Even the naturalists and mystics of more modern times, such as Valentin Weigel, Theophrastus, Paracelsus, Cardanus and Telesius, do not go very deeply into the question as to how and whence man came into the world, but occupy themselves instead in attempting to establish the true relation between divinely created man (microcosm) and the universe (macrocosm). Cartesius, even while admitting that God created man, cannot explain the actual process of creation, and when Leibnitz ad- vances his theory of a world constructed of animate monads proceeding, according to predestined plan, from the first monad, God, by means of ceaseless radiations from the Godhead, he still does not show us how the special creation of man from these monads is to be explained. If we examine the views of the natural philosophers of the more positive school down to the most recent times we find the same result. Even assuming an omnipotent and omniscient God as Creator of the world and man, thought is still baffled as to the manner of their creation. The Almighty had but to will, and all organisms, up to man himself, God's own image, stood complete before him. This was the view held by all those philosophers who found satisfaction in an analytical exposition of detail, while their faith in the Scriptures remained unshaken. Linnaeus, to whom we owe the establishment of the theory of species, cannot rid his mind of the conviction that every form of life had its original corresponding species, and that of every living creature, includ- ing man, God first created a pair. Cuvier, the great authority on comparative anatomy, firmly supported the theory that all created species are original and immutable, and explained the occurrence of new species in consecutive geological strata as resulting from vast upheavals in certain parts of the world, whither, later on, living beings from other parts found their way. Agassiz likewise accepted the theory of these devastating revolutions, but is more consistent in that he supposes an intervention of the Creator after each upheaval, and, feeling INTRODUCTION AND GENERAL CONSIDERATIONS 7 the incessant re-creation of complete organisms to be somewhat too improbable an hypothesis, he takes refuge in the theory that all living beings, man included, originated in eggs created by the Supreme Power. The Koran requires no such sworn evidence. In the fif- teenth Sura it is written : " God said to the angels : ' I will make man out of dry earth and black clay, and after that I have made his form perfect and breathed my spirit into him then shall ye fall down and worship him ' ". The first Arabian philosophers, Alkendi, Alfarabi and Ibn Sina, in spite of their acquaintance with the Aristotelian phil- osophy, were orthodox dogmaticians, and even among the later sects none would have ventured to question the teaching of the Koran ; indeed, the orthodox members of the Hanifilic sect even maintain that all strife and contention over the articles of faith laid down by the Koran is expressly forbidden by Mahomet. The truth of this assertion is supported by the fact that among Mohammedans the creation of man is sometimes discussed, but never his origin. The conception of a simple, natural origin of man can as well arise in the mind of the untaught savage as in the highly cultivated brain of a philosopher. Hence we find among savages traditions that in their essence bear a strong analogy to the teachings of the natural philosophers of all times. Certain tribes of Eastern Asia settle the matter with ad- mirable simplicity by saying that the first man came into existence of his own free will. The majority of primitive peoples, however, who believe in a simple origin of man, endeavour nevertheless to give some satisfactory interpretation thereof, choosing one or other substratum whence man is supposed to have arisen. In the Mautewa Islands of East Africa a demon fished a case, containing human forms, out of the sea, and they grew into men, and the amiable demon turned into a leguan in order to protect them from vermin. On the banks of the Bramapootra the story goes that out of p. swelling on the hand of Kalia Adeo issued the twelve families of the Gonds, who, however, in consequence of an evil smell attaching to them were shut up in a cave by the god Mahadeo, only 8 THE HUMAN SPECIES four brothers escaping. A similar idea prevails in Madagascar, only in this case the first human being, a man, is already created and becomes afflicted with an abscess on the left leg, to which strange source the natives discourteously trace the origin of woman. According to a Slavonian tradition the first man was created out of already-existing organic matter, but here the organic matter is of divine origin, for during his first wandering God grew weary and a drop of sweat fell from him to the earth, where it straightway turned into a man. In America there is a widespread belief that man originally issued from the earth, from caves, or from stones. The Greenlander believes the first man to have been made of clay and the first woman, the mother of all succeeding genera- tions, to have sprung from his thumb. The Iroquois believe themselves to have come from the heart of a mountain, and the Oneidas call themselves " sons of stone " because they believe, like the people of Rotuma in Polynesia, that the first man was made out of a stone. The belief in man having originated in caves is found in Central America, among the Indians of the Antilles, the Carribeans, the Solostos and other Brazilian and Peruvian tribes, the latter even venerating under the name of " paracina " those places where the first human beings are supposed to have emerged from the earth. Under these circumstances, therefore, we need feel no surprise at finding a widespread belief in man's origin in plants. The Salivas, on the Orinoco, believe the first human beings to have been like reeds, others like the fruit on the trees, and a third variety of a nobler type, to have come down from the sun. The national hero of the Goldens in Northern Asia in the course of a pilgrimage through the land came upon a mighty tree whose branches bore round shining discs. With an unerring bow- shot he brought one to earth, but no sooner had it touched the ground than it turned into a human being, a woman, whom the hero married, they thus becoming the progenitors of the tribe. Similar legends of the origin of man are found among the Hereros of South-West Africa, in the Island of Nive in Poly- nesia, and in Samoa, where a creeping plant grew on a rock, and on dying bred worms and afterwards man. Here the animal origin of man is only indirectly implied, but in all parts of the INTRODUCTION AND GENERAL CONSIDERATIONS 9 world legends are to be found treating of man's immediate descent from animals. Among the Fiji Islanders the first boy and girl were pro- duced from a hawk's egg, while the Santals — a Bramapootra tribe allied to the Kolhs — prefer to believe that the progenitors of the human race proceeded from the eggs of a pair of ducks. In New Zealand man originated in an egg laid by a monstrous bird on the water. A Peruvian legend tells how three eggs fell from heaven — gold, silver and copper — containing respectively the princes, the nobility, and the common people. Other tribes of Peru, before the time of the Incas, traced their genealogy from the puma, jaguar, eagle, vulture, etc., just as the North American tribes believe their ancestors to have been the dog, wolf, bear, hare, bog boar, beaver, wild turkey, turtle dove, tortoise, crocodile, snake or salmon. The tribes of North-West America carry their belief in an animal origin so far as to think that their chief ancestors descended from heaven in the form of birds. The result of this belief is the well-known Totemism, in which Virchow tries to find a dim feeling after Darwinism, or relationship with the animal world. We need not dwell upon the belief of the Aleutians in their descent from a dog, and that of the Ainos that their forefathers were bears, but the widespread belief in man's descent from the apes is deserving of more attention, being of great anthropo- logical interest. Savage tribes of the Malay Peninsula, who are regarded by the more civilised Malays as no better than animals, trace their descent from a pair of "unka putch" (the white mountain ape), who sent their young down to the plains, where they reached such a state of perfection that they and their de- scendants became men. Similar to this is the Buddhistic legend of the origin of the platyrrhine races of Thibet ; they are sup- posed to have descended from two very perfect apes and to have been changed into men to people the snowy regions. Another instance we have in the Djatwas of Rajputana who claim to descend from the ape-god Hanuman, and in support of the legend maintain that their princes bear the sign of their origin in a prolongation of the spine. A close examination of these traditions reveals the fact that in every case a process of generation is pre-supposed, a fact io THE HUMAN SPECIES occupying a still more prominent position in those doctrines of creation held by all polytheistic races, whether civilised or un- civilised. As a rule all phenomena of the universe, man not excepted, are attributed to the union of two primitive beings, a male and a female. Signs of this belief are found even among those races who believe man to have simply arisen from the earth. The Indians of New Holland in North America believe that they were literally bom from the earth as from a human mother ; they believe that before the beginning of things there existed a creative force, in female form, which first bore a stag, a bear and a wolf, and uniting 'in turn with each produced the most diverse offspring, till lastly man was born. Naturally, where a female creative force was imagined the idea of a male being was necessarily associated therewith. This belief is held by the Comanches of North America, by the natives of Sumatra, the New Zealanders and the inhabitants of the Marien Islands, and it is invariably through the union of a god, or hero, with a female deity (the Earth) that man has originated. To regard the creation of the world and man as resulting from a process of generation is so entirely natural and consist- ent a point of view for the untaught mind, which necessarily judges everything by its own surroundings, that it is not sur- prising that the priests and philosophers of the older civilisations presented the doctrine of creation in anthropomorphous form, in order to bring it. nearer to the general mind (or perhaps with precisely the opposite aim ?). According to the Egyptian, Babylonian and Phoenician cosmogony, the creation of the world and man results from the union of two primitive beings, the male fair, the female dark. Among all branches of the Aryan race we likewise find the idea of all living beings having descended from two parents ; thus the Indians have Brahm and Brahwani, the Greeks Zeus TraTijp and 4v)/j,iJTvjp, the Romanic nations Jupiter and Rhea. As early as in the Rig- Veda we find the legend of the great parents Dyauspitar and Prthivi matar, and Tacitus mentions the ancient Teutonic legend of the god Tuisco being the son of Heaven and Earth. Among nations of the Mongolian stock, particularly the Chinese and Japanese, it is but natural to meet with the same fundamental INTRODUCTION AND GENERAL CONSIDERATIONS n idea when we consider their special veneration of ancestors. And what are the gods and goddesses wherewith the polythe- istic imagination peoples heaven and earth but personified natural forces called into action at the creation of the universe and afterwards worshipped under the names of heaven, earth, light, etc. ? Nor need we despise this theogony since it is, in reality, the dawn of approaching natural science. One step further and a veil is lifted, revealing the venerable fathers of natural philosophy in earnest meditation over the material causes of the world and of man. First comes Anaxagoras who taught that the earth had brought forth man and beast from the germs scattered over its surface, until they were able to propagate their race alone ; the world, however, was not formed out of the pre-existent matter until that matter was associated with the force-giving spirit. Thus Anaxagoras cannot escape Dualism any more than can Archelaos of Miletus, or Empedocles whose derivation of the organic world from the four elements is extremely interesting : first came plants, then animals and men, whose different parts at first grew separately out of the ground and were afterwards set together by Eros (love, or elective affinity), the most fan- tastic forms being thus accidentally evoked, destined to ultimate destruction. The human being, moreover, was at first a form- less mass of earth and water, cast up by subterranean fires and attaining its perfect form only by slow degrees. Diametrically opposed to the above were the views held by the old Ionian naturalists who, according to the express testimony of Aris- totle, admitted none of the various motive forces of matter. Thales and Pherekydes assume water to be the first element from which all else has proceeded ; Anaximander, infinite sub- stance ; Anaximenes and Diogenes of Apollonia, air ; Hera- clitus, fire (heat). Diogenes and Anaximander alone state their convictions as to the origin of organisms, the former assuming that the influence of the sun's heat caused the earth to produce vegetable and animal organisms ; the latter, however, expressly states that all animals, man included, originated in fish-like form in the primeval ooze and only on the drying up of the earth attained their present form. Neither the Atomists nor the pantheistic Eleatic philosophers seem to have shared this view. 12 THE HUMAN SPECIES Xenophanes argued from the occurrence of fossilised marine animals in high mountains that the earth had passed from a semi-fluid to a solid state. Parmenides, like Democritos, thought the development of man due to the influence of the sun's heat on the earth. In the works of Plato and Aristotle, his disciple, nothing is to be found on the origin of living- organisms. Aristotle, the naturalist so far in advance of his contemporaries, limits himself to a classification of plants, animals and man, in a regular system, and a description of the same on general lines, but as regards their origin he preserves a complete silence. It is owing to the predominant influence of Aristotle on the philosophy of the Middle Ages that the scholastics and their followers so seldom ventured to formulate independent theories on the origin of the world and of man. Strange to say, Ebn Tophail, the Arabian philosopher who died towards the end of the twelfth century, mentions in his celebrated book an earthborn autochthon. " In the temperate zones," he says, " autochthones may actually have existed in former times, the earth producing out of itself, per generationem human forms capable of absorbing the rational spirit, eternally radiating from the Godhead." Even the anti-scholastic Andreas Caesalpinus in the seventeenth century, held it to be possible that animals originated in their perfect form from the effect of the sun's heat on the earth, since they could not have been produced by generation. Other independent thinkers of the sixteenth and seventeenth centuries, while adopting a monistic standpoint, leave us nevertheless in doubt as to their conception of the actual origin of organisms out of "divine substance, itself one with God ". We pass on to the latter half of the eighteenth century when cosmology seemed to enter upon a new era with Kant's theory of the formation of the world. After stating that our solar system with its moons and planets has been evolved from nebulae, and showing that our earth must have required an enormously long period of cooling and consolidation before water could be formed on its surface, it might have been ex- pected that he would extend the theory to organisms, but in his later works, for instance, in the Criticism of the Teleo- INTRODUCTION AND GENERAL CONSIDERATIONS 13 logical Faculty of Judgment^ he firmly supports the dualistic view and ascribes the creation of organisms to God, according to his special aim and intention. Fortunately, about the same time the doctrine of the origin and evolution of organisms found champions in those thinkers who, as forerunners of the great naturalist and philosopher, Charles Darwin, merit our respect. In France it was La- marck, the celebrated author of the Histoire naturelle des animaux sans vertebres, who in his Philosophie Zoologique (published 1809) set f°rth the view that the entire .animal world as at present existing must be considered as descended in changed form from earlier organisms, a theory which was republished in elaborated form in 1815. Lamarck explained the gradual transformation of animals as the result of use and habit, whereas his friend, Geoffroy St. Hilaire sought the cause in the modifications of the qualificative and quantitative state of our atmosphere. Both were defeated in the contest with Cuvier, which Goethe followed with so deep an interest, but the struggle was taken up by other men, each of whom brought to it his own conception of the story of creation. Both Lamarck and St. Hilaire held the theory that the higher organisms have been developed, through progressive modifica- tion, from a few original types of the simplest organisation. Oken, the German naturalist philosopher, could not con- ceive of living creatures having arisen by other means than that of original generation ; hence his view that germs of life, called by him Infusoria, originated in the bed of the ocean, and through the absorption and discharge of gases, in other words through breathing, developed into living organ- isms. In his opinion all higher organisms, man necessarily included, are constructed from an infinite number of Infusoria, and after death are again resolved into the separate elements of the organic substance whence they sprang. Apart from the fact that what Oken described as Infusoria were discovered later on by the microscopist Schwann to be cells, he has still given us no satisfactory explanation of the actual construction of organisms out of his so-called Infusoria, and the progressive development of the lower into the higher forms. i4 THE HUMAN SPECIES The first man in Germany to attack boldly this question was no other than the great poet and thinker, Goethe, whose genius gave him a deep insight into the secrets of the organic world, and made him pre-eminent, even in technical matters, over his contemporaries. His Metamorphosis of Plants, written in 1790, was followed by Comparative Craniology, and in 1818 by Metamorphosis of Animals, in which work Goethe assumes as the leading factors in metamorphosis an internal creative force, the type, and an external creative force, or power of adaptation. Then followed a long series of works by the German naturalists C. Ernst v. Baer, Schleiden, Unger, Viktor Carus, Schaaffhausen and Ludwig Biichner, and by the English naturalists, Erasmus Darwin, William Herbert, Herbert Spencer and Huxley. The way was thus well prepared for Charles Darwin's epoch-making work on the Origin of Species by means of Natural Selection (1859). Darwin adopts the theories of Lamarck and St. Hilaire on the metamorphosis of organisms, but his penetrating mind seeks to prove them on entirely new lines, in that he assumes, as the main agents of metamorphosis, inheritance, individual variation, inherited variation, the struggle for existence and natural selection. His first work treats solely of animal and vegetable organisms, but in his later work, On the Descent of Man, he applies the same laws to the gradual evolution of man from lower forms of life. In the introduction * he vigorously protests against the .attacks of ignorance on science. " It is those who know little, and not those who know much, who so positively assert that this or that problem will never be solved by science." Darwin considers that there is ample justification for the conclusion that man, in common with all other species, is evolved from some lower and extinct form. It was inevitable that a member of the ape family should be selected as the immediate forerunner of man, but that Darwin represents one of the surviving forms of ape as the pro- genitor of the human race is merely a false assertion on the part of his antagonists. Unlike Lamarck, who pleads the 1 Complete Works of Charles Darwin, from the English, by Viktor Carus, Stuttgart, 1875, vol. v., p. 3. INTRODUCTION AND GENERAL CONSIDERATIONS 15 cause of original generation, Darwin does not occupy himself with the question of the origin of life itself. He simply assumes that in all probability every organic being that has ever existed on the earth has descended from some prototype, into which life was breathed by the Creator. Haeckel,1 however, Darwin's zealous follower in Germany, goes further. To him the question of man's origin is not only the question of questions, surpassing all other problems of the theory of evolution, but it brings him back to the question of original generation. He distinguishes two varieties : autogony, or origin of organic matter from an inorganic, non-albuminous fluid, and plasmogony, or origin of organisms in a fluid con- taining carbon in some form. Here natural science coincides with certain of the ancient theories of cosmogony. In many of the old traditions of creation, life was held to have originated in the darkness of the deep, and in the latter half of the last century scientific research actually revealed the fact that in the lowest depths of the ocean, where an even temperature of 4° Celsius is perennially maintained, protoplasm existed in the form of the Gymnocytoda, to which is allied the Bathybius, a low form of life, discovered by Huxley, consisting of a con- glomeration of jelly-like particles. To these succeed in a progressive scale of development the Lapocytoda, furnished with an integumentary membrane, formed by the congealment of the outer surface, then the first cellules with a nucleus, and lastly the testaceous cytoda with nucleus. Like the belief in the central, position of the earth, the conviction of man's central place in Nature dominated thought throughout the Middle Ages. Hence it is oddly inconsistent that the encyclopaedias of the early Middle Ages (Isidor von Sevilla, sixth to seventh century ; the Venerable Bede, seventh to eighth century ; Rhabanus Maurus, eighth to ninth century) and more especially the voluminous works of the scholastic naturalists of the following centuries, place the anatomy and physiology of man side by side with that of plants and animals. Indeed, -in the works of Albertus Magnus on natural science (1193-1280), the description of man receives but scant attention. 1 E. Haeckel, Our Present-day Ideas upon the Origin of Man. Bonn, Strauss, 1899. 16 THE HUMAN SPECIES A fuller account is given by the English writer Bartholomaeus, surnamed Anglicus, in the fifth volume of his Encyclopaedia, De genninis rerum coelestium, terrestmuin et internarum proprietati- bus et de variarum remm accidentibus (1258-1260). Encyclo- paedias comprising human anatomy and physiology were also compiled by the French author Vincentius Bellovacensis (died 1264), the Englishman, Alexander Neckam, and his friend, Alfred de Seresbel, and by the Dutchman, Thomas Cantimpra- tensis, whose bulky comprehensive work, De naturis rerum, was later issued in a smaller edition, in the German language, revised by the Canon of Regensburg, Konrad v. Megenberg ; the work in this form became the first German Natural History and was very frequently published. The first part of this Book of Nature1 deals with " Man in his common nature ". We may pass over the specialists in human anatomy of the latter part of the Middle Ages and the subsequent scientific regeneration of Europe, since they occupied themselves mainly with a close study of the human body itself rather than with theories of man's place in Nature. The founders of modern Zoology, on the contrary (Gessner, Aldrovandi, Swamer- damm, Ray, etc.), were content to compile zoological works, or to publish studies of minutiae without establishing any relation between man and the lower animals. This state of things was completely changed when the great reformer Linnaeus sub- jected the whole world of organisms to observation and exam- ination. He it was, too, who in his zoological system placed at the head of the mammalia the order of anthropomorphous animals (later styled Primates or "chief of animals") wherein man was classified with the Simiae and Prosimiae. This system was revised and man's place more clearly defined by Blumen- bach and Cuvier. They subordinated the order of Quadra- mana (four-handed animals), comprising Simiae and Prosimiae, to the order of Bimana headed by Man, since in man's case alone did they admit the possession of two hands. In Huxley's opinion this view is false, as the apes also have but two hands. The majority of authors towards the end of the last century subdivided the Primates into three classes : (a) Prosimiae, (b) Simiae, (c) Man. 1 Edited by Dr. Franz Pfeiffer. Stuttgart, 1861. INTRODUCTION AND GENERAL CONSIDERATIONS 17 Apes were again subdivided as follows : — (a) The American (New World) Platyrrhines, with broad nasal septum and short bony auditory passage. (b) The Old World Catarrhines^ with narrow nasal septum. The catarrhines, especially the higher varieties, the anthro- poids, are in their physical structure most closely related to man. Robert Hartmann divides the whole order of Primates into three families : — (a) Primarii : Man and the anthropoid apes. (b) Simiae : Apes, both Platyrrhines (broad-nosed) and Catarrhines (narrow-nosed). (c) Prosimiae : semi-apes (Lemuridae). Huxley also places man together with the anthropoid apes in a separate class, stating his reasons for so doing as follows : " The anatomical differences separating man from the gorilla and chimpanzee are not so great as those distinguishing these latter from the lower apes". This opinion has become a general axiom of modern natural science and is approved by Haeckel. In his lecture on the " Origin of Man " he says : " Comparative anatomy applied to the Catarrhine group, proves conclusively that the morphological differences existing between man and the anthropoid apes are not so great as those between the anthropoids and the lowest members of the same group ". Man's place in this order is most clearly defined by Haeckel's classification : — (1) All the Primates, including man, descend from a common prototype. (2) The progenitors of man formed a group of Catarrhines, now extinct. The very earliest ancestors of this group belonged to the lower caudate apes, possessing three or four sacral vertebrae. The later ancestors of the group belonged to the tailless apes with five sacral vertebrae. (3) The Catarrhines form a natural group which may be traced back, directly or indirectly, to a branch of the Prosimiae. (4) The true apes (Simiae) have been developed from the half-apes (Prosimiae). But this classification of man in the order of the Primates did not satisfy the supporters of the doctrine of evolution, 2 iS THE HUMAN SPECIES among whom may be numbered almost all naturalists l ; they demanded a still closer investigation in order to ascertain the relation of man to the other mammals and lower vertebrates. C. Gegenbauer, in his Manual of Human Anatomy? finds nothing in the physical structure of man constituting a funda- mental difference. " In the construction of the human body we find not only resemblances to the organisation of animals but a widely comprehensive correspondence wherever there is a simi- larity of function, a correspondence complete down to the finest structural details ; an absolute uniformity is not to be expected since it is not found even among closely related animals." In spite of the manifold resemblances between man and the lower animals, Gegenbauer feels bound to point out that man in the structure of his bodily organs has not yet reached the highest stage of creation, in that rudimentary organs still persist in his structure ; these, however, are not to be regarded simply as imperfections, but rather as a form of compensation, preparing the way for the organism to attain ultimate perfection. One of the most important points of resemblance between man and the other mammals is the maxillary joint, which dis- tinguishes them sharply from certain birds, reptiles and amphi- bia furnished with a quadrate joint. Further, all mammals have a diaphragm, forming the partition between thorax and abdomen. Their red blood cells are small, circular, and bicon- cave. The skin is covered with hair. All new-born mammals are fed on the milk of the mother. The sucking action has developed the palate and the epiglottis, and is not found in any other class of animals. Man's correspondence to the whole class of vertebrates rests chiefly on their possessing in common a firm inner framework of bone and cartilage consisting of vertebrae and skull, and en- closing the organs of psychical activity, the brain and spinal cord. Common also to all is the ventral heart, as opposed to the dorsal heart of the Articulata and Mollusca ; the early appearance of a respiratory tube distinct from the intestinal 1 The most obstinate resistance was offered by Virchow. Even as late as 1895, in his speech at the opening of the Anthropological Congress at Vienna, he asserted that man could equally well have descended from the sheep, or elephant, as from the ape. 2 Fourth edition. Leipzig, Engelmann, 1890, vol. i., p. 33. DISTRIBUTION OF MANKIND 19 tube ; the highly developed muscular system, and the perfection of the urinary and genital organs. In all these respects man corresponds, broadly speaking, not only to all the other mammals, but to birds, reptiles, amphibia and fishes ; hence all mammals, birds, reptiles, amphibia and fishes must be descended from a common prototype.1 Now as the fishes occupy the lowest position among the vertebrates, Darwin is justified in concluding that all vertebrates are descended from a fish- like prototype. As lowest of the fishes once ranked the Amphioxus lanceolatus with its small, symmetrical, lancet- shaped body, without brain or heart, and, strictly speaking, without a head ; since it possesses in place of a vertebral column merely a Chorda dorsalis, such as is found in the Ascidians, Darwin 2 concludes that here we have most probably the parent form of the vertebrates. Haeckel 3 carries his in- vestigations of man's ancestry still farther back, extending them to still lower invertebrate animals. Thus he takes the Gastraea as ancestor of all the Metazoa, because it represents the gastru- lar stage of all Metazoa, the members of the Volvox genus as representing the blastula stage in the development of the Meta- zoa, and lastly the Protozoa corresponding to the single-celled egg. As connecting link between the lowest Metazoa and the Ascidians on the one hand, and the Amphioxus on the other, Haeckel selects the Frontonia, a class of the humblest chordate animals, from which are descended both molluscs and mammals. The Frontonia form a branch of the invertebrates, which in their turn are probably descended from the Rotatoria, or wheel animalcules. Distribution of Mankind. For many centuries we have unhesitatingly accepted the Mosaic classification of man as descendants of Shem, Ham and Japhet, the three sons of Noah. The tribes described by Pliny in his Natural History and mentioned by Sebastian Munster in his Cosmography (sixteenth century), were regarded as particularly abnormal : the Cynocephali, the Cyclops, the Megapods and sundry other monsters haunted the mind of 1 Darwin, vol. v., p. 206. 2 Darwin, vol. v., p. 208. 3 Haeckel, Lecture, etc., p. 27. 20 THE HUMAN SPECIES the credulous reader, in spite of the voyages of discovery made in the fifteenth century. Natural science had but just shaken off the fetters of scholasticism, and the men had not yet arisen who should bring a clear, unbiassed judgment to bear on the reports of the explorers. The first attempt at a strictly scientific classification of the human race was made by Lin- naeus ; he divides mankind into four races : — (1) The American, physically characterised by reddish colour of the skin, slender stature, straight, thick hair, and almost beardless chin. His temper is choleric. Linnaeus sums him up thus laconically : " He is stubborn, contented, fond of liberty, paints his body in Daedalian style and is ruled by habit ". (2) The European, with white skin, fleshy body, fair, curly hair, blue or grey eyes ; of sanguine temper. " He is active, shrewd, inventive, likes closely-fitting garments and respects the authority of law." (3) The Asiatic, with yellow skin, of compact build, has dark hair and brown eyes and is melancholy in temper. " In character he is cruel, avaricious, fond of show ; he likes to dress in flowing garments and is ruled by prevailing opinion." (4) The African, with black skin, loose build, very black curly hair, velvet-smooth skin, broad, flattened nose, protruding lips ; of phlegmatic temper. " He is cunning, indolent, indiffer- ent, anoints his body with grease and is governed through despotism." In the Linnaean system together with much able, pertinent criticism, there are many erroneous statements ; e.g., the classification of all the diverse tribes of Asia in one group, and the fact of furnishing all Europeans with fair, curly hair and blue or grey eyes. Moreover, it is obvious that Linnaeus is not entirely free from the fantastic notions prevalent among the mediaeval writers of Natural History. Besides the Homo diurnus as highest representative of the Homo sapiens he gives further a four-footed, hairy, speechless Homo ferus on the strength of alleged cases where children grew up among animals without human care. Linnaeus enumerates as Homini monstrosi : — (i) The inhabitants of the Alps, small, active and timid. DISTRIBUTION OF MANKIND 21 (2) Human beings furnished with a single testicle : the Hottentots. (3) The beardless : many American tribes. (4) The megacephalous, with conical heads : the Chinese. (5) The oblique-headed, with skulls flattened in front : the Canadians. Blumenbach's system, which has obtained for so long in the scientific world, though possessing valuable advantages over that of Linnaeus is still not entirely adequate. He gives five races or varieties. (1) The Caucasians, white skinned, with red cheeks, brown, or brownish hair, round skull, oval face, smooth forehead, narrow, slightly aquiline nose, small mouth, perpendicular front teeth, face symmetrical and agreeable. In Europe all nations with the exception of the Laplanders and Finns. In Asia the inhabitants of all parts as far as the Caspian Sea, the Obi, and the Ganges. In Africa, the North Africans. (2) The Mongols, with yellowish sallow skin, straight, thin hair on the head, almost square skull, broad face, shallow and flattened, the nose small and turned up, narrow eyes and pro- jecting cheek-bones. In Asia all nations except the Caucasians and Malays. In Europe the Finns, Lapps and Eskimos. (3) The Ethiopians, with dark brown skin, black, curly hair, laterally compressed skull, bulging forehead, projecting cheek- bones, blunt nose, blending into the prominent upper jaw, upper teeth sloping, protruding lips, retreating chin, femoral bone curved inwards. In Africa, all tribes except those of North Africa. (4) The Americans, with copper-coloured skin, thin, straight, black hair, low forehead, deep-set eyes, rather large nose slightly turned up, broad but not flattened face. Forehead and skull frequently artificially deformed. In America, all aborigines except the Eskimos. (5) The Malays, with chestnut- brown skin, black hair, rather soft, thick and curly, skull rather narrow, forehead rounded, broad nose with thickened tip, large mouth with upper jaw slightly projecting. In Asia, the inhabitants of the Malay Peninsula, the Marian, Philippine, Molucca and Sunda Isles. In Australasia, the islanders of the Pacific Ocean. 22 THE HUMAN SPECIES The advantage of Blumenbach's system consists in the greater prominence given to the relative values of the skull, both the occipital and sincipital, and in the greater exactitude of the geographical distribution, those characters acquired by physical conditions and culture being made subordinate and regarded as secondary race distinctions. Cuvier, the illustrious anatomist, has treated the subject more simply ; following the plan of the Mosaic distribution he recognises only three races : the white, the yellow, and the black, without further particularising their distinguishing char- acters. The latter task was undertaken by the later French naturalists who took into account, as additional race characters, skull, nose and hair. Thus Topinard subdivides each of Cuvier's three races into six sub-races. Darwin, in the Descent of Man, in order to show the inherent difficulty of classifying mankind according to race has compared the views of different authors on the point. Vivey gives two races, Jacquinot three, Kant four, Blumenbach five, Buffon six, Hunter seven, Agassiz eight, Pickering eleven, Bory St. Vincent fifteen, Desmoulins sixteen, Morton twenty- two, Crawford sixty, and Burke sixty-three. Of the more recent classifications Huxley's celebrated system has won pre- eminence by its simplicity. He admits only four principal types, these being variously modified by means of intercrossing. 1. The Xanthochroic Type, half white, fair, with blue or grey eyes, bearded, with abundant growth of hair on the body, dolichocephalous, mesocephalous or brachycephalous skull. In- habitants of the greater part of Central Europe. In the South and West they are replaced by the Melanochroi (Brunettes), a result of intercrossing between Xanthochroi and one of the dark types. In the East is found an admixture of the Mon- golian type. 2. The Mongolian Type, in stature short and thick-set, with golden-brown skin, sleek, coarse, black hair, scanty beard, pro- nounced brachycephalous skull, flat, small nose and oblique- looking eyes. They, inhabit the entire region east of a line from Lapland to Siam. Differing from the type in their skull formation are, first, the dolichocephalous Chinese and Japanese, secondly, the Polynesians, approaching the Australian type and DISTRIBUTION OF MANKIND 23 probably a mixture of Malay with Negrito, and, thirdly, the Eskimos, Greenlanders, and all aborigines of North and South America with their pronounced dolichocephalous skulls. 3. The Negroid Type. — In all individuals of this type the skin and eyes are brown or black, hair of the same colour, short, woolly and not abundant. The skull is dolichocephalous, the forehead rounded and childish, the nasal bone flattened, and the teeth sloping. This type inhabits Madagascar and the region between the Sahara and the Cape of Good Hope. Modifications of the type are the Bushmen and Hottentots, the latter having perhaps originated in an intercrossing of Bushmen and Negro. The Negritos, representing a further modification, resemble the Australian type. 4. The Australian Type. — The representatives of this type are characterised by a dolichocephalous skull, extremely prominent eyebrows, unusually large teeth (especially the canines), and the sloping position of the upper front ones. In stature they are tall and long-limbed, with skin of a choco- late brown and black hair, long and woolly. This type is found on the mainland of Australia and in the heart of the Deccan and Hindustan. According to Huxley, representatives are also to be found in Egypt, but it is not clear to what tribe he refers. Amongst the systematists the philologist Friedrich Miiller occupies a special position. Had he attempted to base his distribution of mankind solely on linguistic differences he would necessarily have failed, since it is well known that the most diverse peoples speak the same language. This it was which led him to adopt, in addition to language, the hair as dis- tinguishing character. Hence he gives two principal types: — 1. The Woolly-haired Type, namely, the bushy-haired Hottentots and Papuans and the fleecy-haired African Negroes and Kaffirs. 2. The Sleek-haired Type, namely, the straight-haired Aus- tralians, Eskimos, American Indians, Malays and Mongols, and the curly-haired Dravidians, Nubians and inhabitants of the Mediterranean coasts. Miiller's classification gives us twelve races subdivided into tribes according to language and race, but race and language seldom coincide. In spite of the 24 THE HUMAN SPECIES complexity of this system, on the whole there is real merit in Miiller's classification of the Middle European races, under which head he includes : — 1. The Basques. 2. The Caucasian tribes. 3. The Hamito-Semitic peoples. 4. The Indo-Germanic race. Does Mankind Consist of One or of Several Species ? As we have already seen in the mythologies of all nations man has sprung from a single pair of beings, but, be it observed, by the term " man " was understood only the particular nation concerned. On a closer examination, however, we are faced, not only in the legends of wild tribes but also in the Mosaic story of the creation, by the contradictory statement that the descendants of the first human parents have dealings with other beings who must have been created either before or together with themselves. Even Linnaeus professed himself a staunch adherent of the Biblical faith, but since those days scientific research has raised many a weighty argument against that faith. Karl Vogt,1 for instance, considers it beyond question that the human race has descended from several species originally distinct from each other as are the rest of the mammals; further, that during the countless ages of man's existence, those manifold bastard forms have arisen which we now call intermediate types, varieties or races. Haeckel gives the Veddahs as the lowest of the sleek-haired races, and the Akkas as lowest of the curly-haired, and con- siders it probable that still lower down at the common (Plio- cene ?) root the two chief branches of the human family blend into one. These two pigmy forms Haeckel regards as true species of the genus Homo, and vigorously protests against the assumption of a single human species. In this view he is supported by Dames, who asserts that were any animal but Man under discussion the widely differing characters would lead every zoologist to subdivide them into several genera and numerous species. The illustrious Quenstedt expresses himself 1 Karl Vogt, Zoolog. Briefe. Frankfurt, 1851, vol. ii., p. 553. ONE OR SEVERAL SPECIES 25 similarly : " If Negro and Caucasian were snails, the zoologists would unanimously declare them to be two perfectly distinct species that could never have arisen by gradual divergence from a common parent form ". In opposition to this view, the ma- jority of naturalists (Kollmann, Virchow, K. E. v. Baer, Ranke, etc.) agree in classifying man as a single species, their opinion being that the existing differences are not sufficiently distinctive to constitute different species, and hence that it is not a ques- tion of species, but rather of varieties or sub-species. With his customary critical thoroughness Darwin has stated his opinion on the subject so long discussed by the polygenists and mono- genists. The former argue that the various so-called races are found, on careful comparison, to differ importantly from one another, not only on anatomic-physiological lines (texture of the hair, relative proportions of the body, capacity of the lungs, form and cubic content of the skull, convolutions of the brain, etc.) but also on psychological and pathological lines. Now as these characters have persisted for thousands of years, and the different races have adjusted themselves to different climatic conditions, and have even different parasites (Pediculi), we may, without hesitation, infer that man consists of several species, more especi- ally when we remember that certain races are completely sterile when crossed. On the other hand the monogenists, whose theory was supported by Darwin, hold the view that the most distinct races possess a greater resemblance to one another in respect to form than is usually admitted. Further, that the chief distinctive race characters (formation of the skull, features of the face, colour of the skin, and distribution of hair on the body) are extremely variable, and, most important of all, the races graduate into each other. Now it is usual to unite all the forms that graduate into each other under a single species ; hence applying the same principle, there can be but a single human species. This view is supported by the fact that for many centuries the most complex intercrossing of the different races has gone on, and that all races bear a striking resemblance to one another in tastes, manners and customs, expression of the emotions, and the use of weapons and ornament. The question as to whether the separate races (sub-species) each originated from a single pair of progenitors has given rise 26 THE HUMAN SPECIES to a great deal of discussion. With domestic animals this is quite possible, provided that the varying descendants are most carefully selected for pairing. According to Darwin, the origin of most of our races is to be attributed not to a single pair of methodically selected progenitors, but rather to many indi- viduals, which varied, though perhaps in ever so slight a degree, and these variations were either natural or artificial ; hence, we may assume that in all probability the races of man have arisen in a similar way, whether through the modifying in- fluences of different physical conditions, or through the indirect effect of natural selection, more particularly of sexual selection.1 In comparison with sexual selection the influences due to climate, environment, continued use of parts and the law of correlation are of secondary importance. The fundamental precept, however, upon which all recent research as to man's origin must rest, is the conclusion with which Darwin closes his work on the Origin of Man, namely, that we are bound to acknowledge that man is descended from some lowly organised form. The Ancestors of Man. In his work, On the human teeth found in the pisolitic iron ore of the Swabian Alps? Branco assumes that the favourable moment for man's development from his animal prototype was during the Tertiary Period. It was not the severity of the struggle for existence that caused man to rise from the animal world ; indeed it was precisely this struggle that prevented the anthropomorphous animals from attaining to human state. " The struggle for existence had to be lightened for the develop- ment of man from an anthropomorphous ancestor to become possible." As superior equipment for the struggle Branco suggests the erect position, and the higher development of the hand and brain. Only on assuming an erect attitude could the hands become free ; Dames even goes so far as to say that man only became human when he learnt to stand firmly on his feet. At first the hands still required a support (such as trees, etc.), but gradually early man learnt to walk independently and left 1 Darwin, vol. v., pp. 218-37. 2Wiirtheim, Jahresheftef. vaterl. Naturkunde, 1898, p. 70. THE ANCESTORS OF MAN 27 the woods. As to the causes to which the erect position may be due, two points come under special consideration : first, the great weight of the body (Ch. Morris) which may well have led to the abandonment of an arboreal existence, and, secondly, the shortness of the legs. According to Morris, i man's half-human progenitors must have had short arms, similar to those of existing man, ill adapted for quadrupedal progression, and consequently the feet must have been already perfected for locomotion. The free use of the arms resulted in a higher development of the brain. No such intermediate form, as described by Morris, has ever been discovered, but, as Branco points out, fossil anthropoid remains of any sort are very rare, the Pithecanthropus being the only specimen pronounced by naturalists to be an "ape- man ". It will be quite clear, therefore, that Branco belongs to those zoologists who derive man from some extinct anthropoid, and not from any still existing species. Haeckel has been most consistent in developing the theories of Darwin, and has drawn up a genealogical table, which, having the Prosimiae (semi-apes), and Lemuridae, at its base, leads us up to the Simiae (apes), viz., the Catarrhines of .the Old World, and the Platyrrhines of the New World, and finally to the anthropoids, viz., the Chimpanzee and Gorilla of Africa, and the Orang and Gibbon of Asia. The group of Tertiary anthropoids gives rise to the " speechless ape- men," and these again to the Homo sapiens. E. Dubois's arrangement of the genealogical tree differs slightly from that of Haeckel in that he starts from the Proto- hylobates (primitive Gibbon). As its descendant we have the Palaeopithecus of the Sivalik stratum, next the Pithecanthropus erectus, and finally Man. From a lateral branch of the Proto- hylobates Dubois derives the Pliohylobates and the Gibbon ; and similarly from the Palaeopithecus, the Orang, Chimpanzee and Gorilla. Each of the above authors bases man's genealogy on the anthropoids, but a different view is held by Schlosser, who maintains that the New World Platyrrhines are far more closely related to the Old World anthropoids, and to man, than is usually admitted. That the Platyrrhines possess thirty-six teeth Schlosser regards as of secondary importance, but of great significance is the high finely arched skull, especially in the 28 THE HUMAN SPECIES Cebus genus. In his opinion the Cebidae are descended from Prosimiae, or Lemuridae which migrated from North to South America. Briefly put, Schlosser's theory is as follows : The anthropoids and man are the advanced descendants of Platyr- rhines which underwent transformation during the Tertiary Period. One grave objection to the theory is that up to the present no anthropomorphous fossils have been discovered in South America ! Quite recently Rhumbler, in tracing man's descent from earlier anthropoids,1 followed closely Darwin and Haeckel, and laid stress on the number of morphological characters possessed by man in common with the anthropoids which are absent in other mammalia. In his opinion it is impossible that the human foot, one of the most eminently distinctive characters of man, can have been evolved from the prehen- sile foot through climbing large trees, as suggested by Klaatsch. Rhumbler considers it far more probable that during the transition to the erect attitude the opposable first toe of the prehensile foot was the chief part to come into contact with the ground, and that in this way according to the law of adaptation it acquired its present importance as one of the three points of support for the human body. It has been remarked already that Charles Morris is of the opinion that the shortness of the human arm has been inherited and not acquired. According to E. D. Cope 2 man also inherited a foot adapted for locomotion. Both these views are fundamentally opposed to the anthropoid origin of man. According to Cope's theory, man's early progenitors never led an arboreal life, whereas the foot of the ape has become prehensile through adaptation. Cope assumes the common parent form of man and the apes to have been the Phenacodus, an order belonging to the early Tertiary Period, which must have possessed a prehensile hand and a foot con- structed for support and locomotion. From the Phenacodus, remains of which are found in the oldest eocene strata of 1 Corr.-Blatt d. deutsch. Gesellsch.f. Anthropologie, etc., 1904, No. 8, pp. 62-64. 2 The Geological Magazine, London, 1886, p. 238. FOSSIL APES 29 North America, and occasionally in Europe, the apes and man are descended on the one side, and on the other the un- gulata (hoofed animals) and the carnivora. This view is shared by Topinard. Klaatsch also denies any special importance to the anthro- poids among man's progenitors, but seeks his origin in still earlier forms of the mammalia. He assigns great importance to the teeth. Taking the highest figures that have been obtained from the observation of anomalous cases of every kind of human being, and arranging them synthetically, he arrives at a set of teeth corresponding not to that of the apes, but to that of much earlier eocene mammals. Similarly, the protuberances of the molar teeth in man correspond to the same in groups of eocene mammals. Klaatsch further points out that the opposable thumb is not peculiar to man and the apes but was present in the parent form of all mammals ; nor did the special development of the great toe originate with the apes, it being found in the prehensile foot of certain half- apes. In the opinion of Klaatsch the great toe acquired its present importance through man's ancestors having climbed very thick-stemmed trees requiring a firm side pressure of the prehensile foot against the trunk. The theory that several lower animal forms have served as the fundamental form of man is unconditionally rejected by Klaatsch, for, he argues, only to adduce two proofs, it is inconceivable that the redness of the lips and the presence of hair in the armpits, both dis- tinctive characters of man, should have been repeatedly de- veloped from different animal ancestors. Fossil Apes. Up to the present the fossil remains of apes that have been discovered are not abundant, although of extreme interest, especially to those naturalists who base the origin of man on the anthropoids of the Tertiary Period. Fossil remains of apes have been discovered from the year 1836, and have been described by the most experienced palaeontologists ; they were formerly not recognised as such and were not admitted by Cuvier to the end of his life. Fossil apes and semi-apes have been found more abundantly during the last decades of the 30 THE HUMAN SPECIES nineteenth century, among others a gigantic semi-ape, dis- covered by Forsyth Major in Madagascar. These discoveries led the indefatigable Haeckel to draw up a complete scale from the earliest fossil semi-apes to the anthropoids and man.1 At the base stand the early eocene Pachylemurs with forty-four teeth ; then follow the eocene Nekrolemurs (Adapidae) with forty teeth, and the Autolemurs (Stenopidae) with thirty-six teeth, like the New World Platyrrhines. Remains of the teeth of a macacus, named by the discoverer Inuus suevicus, have been found at Heppenloch near Kirchheim-unter-Teck (Jura Alps, Swabia), and ascribed to the pliocene age. Of still greater interest to us are the fossil remains of anthropoid apes (see Fig. I, a). The most ancient relic found in Asia is the remnant of an upper jaw, discovered in the Sivalik strata of India. Standing alone and probably belonging to the pliocene period is the anthropoid ape called by palaeontologists Palczo- pithecus sivalensis ; it is distinguished by a comparatively narrow palate, and molars resembling those of the gibbon and chimpanzee, but still more closely those of man. The discovery of fossil anthropoids in Europe dates from 1836. The remains found were most frequently those of the Plio- pithecus antiquus, and were chiefly jaw-bones, upper and lower, furnished with teeth ; this anthropoid is held by Schlosser and Zittel to be identical with the gibbon, but is regarded by Dubois as representing a separate order of long-armed apes, now extinct. Judging from the distribution of the fossils, the Pliopithecus antiquus inhabited a region extending from the north, south-east, west and south-west of France over Switzer- land to Steiermark. Another extinct gibbon of the early pliocene period is the Pliohylobates, surnamed Eppelsheimensis, from Eppelsheim, the place of its discovery. The fossil femur closely resembles the corresponding bone in man ; indeed, Pohlig, from the presence of a linea aspera, declares this gibbon to resemble man far more closely than any other, extinct or living. Still greater interest was aroused by the discovery of the Dryopithecus Fontani in the south-west of France, in the middle of the nineteenth century. At St. Gaudens, Haute Garonne, the first relics brought to light were two halves 1 Haeckel, Lectures, p. 22. FOSSIL APES 31 of an under-jaw and a humerus, apparently that of a young animal, and later on another jaw was discovered near St. Gaudens, and judged by Owen to be indisputably that of a gibbon. The humerus, as well as the teeth, is strikingly human, according to the testimony of most natural- ists; indeed, both in the first place were attributed to man. This Dryopithecus underwent, op the whole, many vicissitudes. At first it was considered the most human of fossil apes, only to be later declared by Gaudry and Zittel as the least human, a conclusion again disputed by Pohlig and Schlosser. Here, as usual, the truth is to be found midway between the extremes. Judging from the formation of the teeth and the very slight prognathism, there can be no doubt, says Branco, FIG. i. a, Mesopithecus Pentelloi. b, Skull of a gorilla. (Homes, Urg. d. M.) that the Dryopithecus in these respects is most closely related to man, but there are other points to take into consideration. In the first place, it has been pointed out that the tongue of the Dryopithecus occupies a much smaller space than is the case with any other anthropoid, but truth compels us to admit that in this respect an approach to the anthropoid type is found among many wild tribes, e.g., the Sambaquis, the Cayapo Indians and the Nago negroes. Gaudry has drawn attention to still another characteristic of the Dryopithecus lower jaw, which detracts from its claim to human resemblance, viz., the retreating chin sloping backwards from above ; Gaudry's in- vestigations have shown also that the wisdom teeth were not, as at first supposed, erupted at a later date than the others, nor 32 THE HUMAN SPECIES are the eye-teeth specially small. Nevertheless, the Dryo- pithecus has so much in common with man that it must rank as one of the most remarkable phenomena in the whole pedigree of man. To the Dryopithecus belong probably also the teeth of anthropoid apes, found since 1850 in the pisolitic iron ore of the Swabian Alps, consisting of one lower pre- molar (milk-tooth), two upper molars, and seven lower molars. The two upper molars were at first declared by Owen to be human teeth, and Quenstedt was the first to assign them to an anthropoid, though he admits that their resemblance to human teeth is so close as to be misleading. Branco gives an exact description of each tooth, and arrives at the conclusion that they bear the closest resem- blance to those of a gibbon, in fact a Dryo- pithecus. Whether this particular Dryopithecus was a Dryopithecus Fontani, or the mem- ber of another species, FIG. 2. Restored skull of the Pithecanthropus he leaves undecided. Doubt and uncertainty surround the most recent important discovery of anthropo- logical palaeontology, namely, the fossil remains found in Java (1891) in the Upper Tertiary strata and described by the discoverer, E. Dubois,1 as Pithecanthropus erectus, an inter- mediate form between the anthropoid apes and man (see Fig. 2). The remains found include a third right molar tooth, a left femur and a second left molar. As Dubois points out, the extraordinary resemblance to man is less in the teeth, though they too are sufficiently characteristic, than in the cranium and femur. The most striking points about the skull are the absence of the special structure peculiar to all other anthropoids, and its great capacity, reckoned at 990-1000, or two-thirds of the capacity of the human skull. 1 E. Dubois, Pithecanthropus erectus, eine menschenahnliche Uebergangsform aits Java. Batavia, 1894. TERTIARY MAN (PLIOCENE AND PLEISTOCENE) 33 The line of the profile resembles that of the most pithecoid races of man : the Veddahs of Ceylon and the Akkas of Cen- tral Africa. The femur, with a slight forward curve, is of a length and thickness proportionate to the frame of a man of medium height and of normal weight. Dubois is of the opinion that these remains belonged to a creature representing the intermediate stage between anthropoids and man, so long the object of Haeckel's search, a descendant of the anthropoid species Anthropopithecus sivalensis. Remains of Anthropo- pithecus sivalensis have been found in the Upper Tertiary stratum of India, namely, an upper jaw with the teeth ; it is of a short, broad, horse-shoe shape, like the human jaw, so that the beginning of the possibility of speech already existed. Besides Dubois and Haeckel, the naturalists Dames, Manou- vrier, Marsh, Nehring, Petit and Vernau believe the Pithecan- thropus to be neither man nor ape, but an intermediate form between the two. The skull has been almost as often declared by naturalists to be that of an ape as that of a man, and most authorities are agreed that the femur closely resembles the human bone or even actually belonged to a man. According to Branco, the Pithecanthropus was undoubtedly an ape, but an ape well able to stand erect owing to the occipital cavity being situated nearer to the middle of the base of the skull and the occipital bone being sharply curved forward. Finally, when we take into consideration the large, well-arched skull with its spacious brain-cavity, we may infer that the Pithecanthropus erectus was distinguished from all other anthropoids by special powers of intelligence. Tertiary Man (Pliocene and Pleistocene), The discovery of the Pithecanthropus erectus has made the question of Tertiary man's existence one of burning inter- est, though it had long played an important part in all anthro- pological journals and at anthropological congresses, and was well worthy of the attention bestowed upon it. Since the remains of Quaternary man have been found in Europe, Asia, North and South America, we necessarily infer a Tertiary man as ancestor of the Quaternary man, as the 3 34 THE HUMAN SPECIES latter could not have arisen suddenly, through a trap-door, as it were. Schlosser has expressed his opinion on this subject with unmistakable clearness in the " Literaturbericht fiir Zoologie," 1883 (Archiv fiir Anthropologie, pp. 160, 289). Since not only most of the mammals, but also most of the anthropoids, ex- isted in the Pliocene Period, it would be remarkable, says Schlosser, if man had not also existed at that time, but he considers it probable that Tertiary man differed widely, both physically and mentally, from the species Homo of the present day. It must be admitted that clear proof of the existence of Tertiary man is as yet very scanty, being limited to discoveries in two different places. In a hard conglomerate, undoubtedly Tertiary, in Burma, remains of hewn flint stones were found, one in the form of a stone knife, together with the tooth of a hipparion. Still more interesting are the discoveries in the loess of the Pampas of South America. Here in the lowest stratum, unquestionably belonging to the Tertiary Period, numerous traces of man's existence were brought to light, such as weapons, carved bones, marks of former fireplaces, and human skeletons (small and dolichocephalous). It is character- istic of these places of discovery that the glyptodon is gener- ally found together with the traces of man's existence. In one cavity a skeleton was found under the carapace of a glyptodon, no other remains of the glyptodon being present. Other glyptodon carapace having been found in a perpendi- cular position — -serving perhaps as screens — -we can but ton- elude that Tertiary man slew the giant armadillo in the chase and robbed it of its carapace for his own purposes. It is no matter for astonishment that so few fossil remains of Pliocene man have been found when we compare the scanty discoveries of Pliocene anthropoids and bear in mind that, in all probability, the entire number of human beings in the Pliocene Period did not exceed a few thousands. Certain French and German naturalists believe that they have discovered traces of the presence and activity of Tertiary man, though not in the form of skeletons or bones. Mortillet attributes the fragments of flints found near Thenay, in France, to a hypothetical anthropomorphous being, and the palaeon- TERTIARY MAN (PLIOCENE AND PLEISTOCENE) 35 tologist Gaudry was inclined to assign to the Dryopithecus similar fragments collected from the Tertiary limestone of Beauce, near Paris, by Abbe Bourgeois. Since Mortillet took up the subject, the Pleistocene flint tools, the so-called " eoliths," have never ceased to be brought forward as proof of man's existence towards the end of the Tertiary or beginning of the Quaternary period, Rutot, in France, and Klaatsch, in Germany, vigorously defending the theory. In judging doubtful flint implements of the Upper Tertiary strata Mortillet attached the greatest importance to the bulbe de percussion, Rutot to the retouche. Rutot does not admit the possibility of their having been formed by natural agencies (change of temperature, strong water-currents, sea-waves, movements of strata), and his investi- gation of various strata led him to classify the consecutive zones as Reutelia, Mesvinia and Mesvino-Chelle'a. Besides hewn stones, specimens of which are said to have been found also in Portugal by Ribeiro, carvings on bones were regarded as proofs of the existence of Tertiary man, and are thought to have been produced by means of a flint instrument. Capellini found crescent-shaped carvings on the bones of a Balaenotus, Desnoyers has drawn attention to carvings on bones of the Tertiary Period from the sand-quarries of St. Prest, and von Diicker believed he had found traces of man's work on the bones of a hipparion from Pikermi (Greece). Virchow and Ranke hesitated to pronounce the Tertiary flints the work of man. Virchow, while admitting the possibility of other explanations, inclined to the bslief that they had been cleft by fire. Zittel,1 the geologist and palaeontologist, ex- presses himself more positively. In the flint fragments in ques- tion, he sees merely the work of natural agencies, fragments that have been split asunder by meteorological processes and re- sembling those, for instance, that are scattered for miles over the surface of the Libyan desert. Homes 2 shares this view in «very particular, and regards the so-called flint implements of the Upper Tertiary strata, brought forward by Rutot, and •defended by Klaatsch, as merely illusory natural phenomena. There would be no difficulty in collecting from the thousands of 'Zittel, Handbitch der Paliiontologie. Munchen, 1893, vol. iv., p. 710. 2 Homes. Der diluviale Menscti in Eitropa. Braunschweig, 1903, p. 22. 3* 36 THE HUMAN SPECIES flintstones in West Flanders a whole series having the appear- ance of bsing hewn. Homes and Szombathy have pointed out that both the bulbe de percussion and the retouche could have arisen in a perfectly natural way. The only absolutely reliable proofs of an apparently hewn stone having been artifici- ally produced lie in the character of the outline and the re- gularity of the retouche; Rutot's flintstones fail in both these requirements. This is severe criticism, but any one who, like the writer, has had frequent opportunity of examining whole series of alleged Tertiary stone implements will not think it unjust, for the bone carvings are extraordinarily vague and deceptive. In Ranke's opinion the incisions may equally well have been caused by natural agencies, such as sharp-edged stones, the teeth of rodents (porcupine, beaver), the swordfish, etc. Moreover, Homes is entirely justified in emphasising the fact that up to the present no traces of encampments or dwell- ing places from the Tertiary Period have been found in Europe. To sum up : Tertiary man probably existed in Europe but we have as yet no definite proof thereof. The stature of the Tertiary man must remain a matter of conjecture, since we do not know whether it is possible to assign the proportions of the South American Tertiary man to the alleged European. The effect of civilisation on the human body being partly injurious, weakening and stunting, partly beneficial and favourable to growth, man's ancestors, as Branco : remarks, may have been taller, or shorter, than the average man of the present day. If we accept as a fact that giants lived in Europe in the Tertiary Period, it must be remembered that no traces of any giant descendants of theirs have ever been found in any part of the world. Kollmann assumes that Tertiary man was a pigmy, and regards as his descendants the neolithic pigmies of South-East France and Switzerland, and the still existing pigmy tribes of Africa, Asia, Europe and America. This, how- ever, is but another hypothesis, and one which can only find support in the low stature of the Pampas skeletons of Tertiary man in South America. Admitting the existence of Tertiary man, where shall we seek his birthplace and primitive home ? The recent discovery 1 Branco, loc. fit., p. 113. TERTIARY MAN (PLIOCENE AND PLEISTOCENE) 37 of the Pithecanthropus in Java has again brought this question into prominence, for, needless to say, the generally accepted legend to the effect that the Mesopotamian Paradise was man's first home can be regarded by scientific anthropology as nothing more than legend. Danvin acted as pioneer in this question. Arguing from the theory that man is a lateral descendant of the Catarrhine stock, and that these exist, and have existed only, in the old world, he reasons that Australia and the islands of the Pacific are necessarily excluded from being man's original home. As, also, the early progenitors of man must have been inhabit- ing a hot country at the time of losing their hairy covering, and as in each great region of the world the living mammals are closely related to the extinct species of the same region, Darwin i concludes that Africa was probably man's birthplace, especially as it is probable that Africa was formerly inhabited by extinct apes closely allied to the gorilla and chimpanzee. In recent times the old theory has been revived of Aus- tralia being the birthplace of man, and Schbtensack - of Heidelberg has spoken, and written much, in its defence. In his opinion it is not to be supposed that the development of man from a lower form has been the result of so severe a competi- tion for life as that experienced by the anthropoids and other mammals, for man being unequipped by nature, and still in- capable of making weapons for himself, could not have competed in a struggle against powerful beasts of prey. No part of the world could have been more favourable to man's development than Australia, for the struggle for existence must have been milder there than elsewhere, the hunting of the marsupial fauna offering no particular danger. Schotensack nevertheless assumes South-East Asia to have been the first home of man, the Pithe- canthropus having been found in Java. From this point the de- scendants of the Pithecanthropus spread to Australia by way of the Celebes and New Guinea, which in the Pliocene Period were still connected with the mainland. In support of this the- ory Schotensack says : The Australians of the present day may 1 Darwin, loc. cit., vol. v., p. 203. 2 Dr. Schotensack, Die Bedeutung Australian fitr die Heranbildvng des Menschen aus einer niederen Form. Verhandlung des natur-med. Vcrcins. Heidelberg, 1901. 38 THE HUMAN SPECIES be described as the remnant of a very ancient race both in physical and cultural respects. At the time of their discovery they were ignorant of the art of pottery and of the use of bow and arrow ; their only instruments were the boomerang and the throw-stick, both of which have been found amongst palaeolithic remains in other parts of the world (also in Europe). Schoten- sack further assumes that when early man migrated from Australia back to Asia over the isthmus he took these weapons with him and thus spread their use. The arts of pottery and stone-grinding, and the use of bow and arrow, he learned later on in other lands. Those who had remained in Australia could have no share in these inventions, for the Pliocene isthmus became later submerged. Schotensack also points out that the Aus- tralian, in order to obtain the wild honey that was to be had in abundance, must have climbed high trees, whereby the great toe developed gradually its present position and significance as a distinctive character of man. The Australian had discovered the art of making fire, and subsequently that of cooking, the frequent thunderbolts and prairie-fires having taught him the meaning of fire and its effect on the flesh of animals. In conclusion we must make mention of the dingo (the wild dog of Australia), an animal introduced into Australia by man and representing in that land the only non-marsupial mammal. The dingo was domesticated by man, and this probably led to the domestication of the wild dog by those who had migrated from Australia to other parts of the world. Schotensack's view is shared almost entirely by Klaatsch, the latter merely suggesting that man migrated to Australia before the Pliocene Period, even returning to Asia over the Pliocene isthmus, since it has been all but proved by the dis- covery of eoliths that Tertiary man existed also in Europe. We have seen above how far this statement may be regarded as conclusive, but on other grounds the Schotensack theory has no lack of antagonists. Rhumbler J does not deny that the Australian corresponds in many ways to Palaeolithic man, but he considers it far more probable that the great continent of Europe-Asia, connected with America by the Behring Straits, was the first to be inhabited by man, and that at an extremely remote period a 1 Corr.-Blatt f. Anthropologie, etc.. 1904, p. 64. QUATERNARY MAN 39 part of the human race migrated to Australia and were eventu- ally cut off from their fellow-beings. In support of this theory there is the fact that all the more highly developed forms of the mammalia have occurred without exception on the great continent. The greater the continent the more numerous will be the individuals inhabiting it, hence the greater probability of some among those individuals surpassing the rest by reason of their superior organisation. This proposition may equally well be applied to man. Klaatsch, for instance, has pointed out that both the skull and the extremities of primitive, diluvial man bear a greater resemblance to those of the Mongolian race than to those of the Australian. In any case he attributes, as does also Const. Konen, the Neanderthal man (see below) to an extremely remote geological age, at the latest the Upper Pliocene Period. Quaternary Man. While the evidences of Tertiary man are somewhat limited, diluvial (Quaternary) man has bequeathed us not only his bones and teeth, but human portraits — the work of his hands- giving the rough outlines of his stature. Even when both skeleton remains and portraits are absent from his former dwelling-places, there exist the traces of his activity in the form of weapons and tools of stone, bone and horn, besides the tubular bones of the animals he slew in hunting, and hearths where he cooked their flesh. From the differences existing between the various stone implements and animal bones examined by him, Mortillet concluded that Diluvial man passed through four stages of culture. It should be borne in mind that although this may be applied to France it does not hold good for the rest of Europe (and at present we are considering Europe alone) ; for the climate of France, especially in the south, admitted of uninter- rupted habitation and the unbroken development of its human inhabitants, whereas in all other parts of Middle Europe habita- tion was interrupted by the intervening Glacial Period. Morlillet's four periods are as follows: — (i) The Chelles period (from Chelles in the Seine et Oise Departement) with a warm, damp climate and a warmth-loving 40 THE HUMAN SPECIES fauna. The man of this period was of a low order, and em- ployed both as weapon and tool a thick, heavy, rough-hewn flint like a cudgel (coup de poing], (2) The Monstier period (from Moustier in Dordogne). Re- presentatives of this period are to be found also in those parts of Italy, Germany, Austria and Poland, that escaped the influ- ence of the Glacial Period. It was marked by a cold, damp climate, and its fauna was suited to these conditions. Man had progressed, and no longer used the heavy cudgel, but had hand-picks, hewn only from one side, and racloirs. (3) The Solutre period (from the place of the same name in the Saone et Loire Departement) with a dry, temperate climate. Man shared this period with the reindeer, wild horse, and mammoth ; he shaped his flint like a laurel leaf and sometimes even furnished it with a handle. (4) The Madeleine period (from La Madeleine in Dordogne) was again cold and dry, so that the mammoth died out, but the reindeer was still to be found in abundance. The man of this period preferred light, narrow stone-knives, made tools out of bone and horn, and possessed marked ability for drawing and carving on bone and horn. Homes x combines the Chelles with the Moustier period, thus reducing the four to three. The earliest period he subdivides into two stages, the first of which, following on a Pliocene Ice Age, comprises the discoveries at Tilloux, Mosbach and Sudenborn (near Weimar), the Elephas meridionalis, antiquus and/r/>;«- genius, and man ; the second contains the discoveries made at Tanbach, Elephas antiquus, rJiinocerus megarhinus, Cennts giganteus, the reindeer and man. The human remains from the Diluvial Period, when man dwelt partly in caves, and partly in colonies in the open country, may be arranged in three categories according to their antiquity. To the oldest and at the same time lowest race of man (corresponding to the Chelles- Moustier period) belongs the Homo antiquus. Remains of the same have been found in France at Tilloux, Villefranche and Moustier; in Belgium in Spy Grotto ; in Germany at Tanbach, in the Neanderthal caves at Diisseldorf and in the Riibeland caves ; in Austria at Krapina 1 Homes, he. cit., p. 6. QUATERNARY MAX 41 (Croatia), and in the Stramberg cave ; in Russian Poland in the lower cave of Wierschowic. The low stage reached by Homo antiquus is most strikingly shown by Neanderthal man with his massive skull, strongly projecting brows, retreating forehead and chin, and the curved bones of his extremities. Virchow, who was inclined to look at the pathological side of everything, declared the remains to be those of an old man whose bones had been rendered crooked in childhood by rickets, and his joints attacked in old age by deformative rheumatism. This then was the verdict for the Neanderthal race, and yet Virchow asserts that among the Frisians, individuals with the same dolichocephalous skulls, and the same projecting supercili- ary ridge, are to be commonly found. Even in the fragments of a lower jaw found in the Sipka cave Virchow endeavoured to discover some pathological character ; the two teeth next to the right eyetooth, viz., the two right pre-molars, are deeply imbedded in the jaw, and Virchow, considering their great size, thinks this to be an example of retention of temporary teeth in an adult. Walkhoff, however, has pointed out that this is no sign of retention, nor does it point to a race of giants, as Wankel suggests ; it is the normal jaw of a prehistoric child of about ten years of age with, it is true, somewhat extraordinarily large teeth. Another striking peculiarity of this lower jaw is the rudimentary state of the muscular attachment of the digastricus and genioglossus, which in conjunction with the absence of chin points to a very low stage of culture and but rudimentary powers of speech. The fossil remains found at Krapina (Croatia) may be referred to a similar period, and consist of teeth and fragments of bone belonging to at least ten individuals of various ages. The brows are still mere prominent than in the Spy and Neanderthal skulls, the jaw being enormously developed, with a still more retreating chin than that of the Sipka jaw, and the remaining molar teeth are marked by corrugations of the enamel of a pithecoid nature. Equally striking is the rudi- mentary state of the muscular process for the genioglossus muscle. Viewed in the light of Walkhoff s explanation of the Sipka jaw, the discoveries at Krapina, together with all the above- 42 THE HUMAN SPECIES mentioned remains of bone and teeth, may be referred to an early Palaeolithic race ; Schwalbe and Klaatsch in the meantime had subjected the Neanderthal man to renewed investigation, and indisputably established his low type of development. Ac- cording to Klaatsch the Homo recens, the Neanderthal man, and the Pithecanthropus erectus are descended from a common parent belonging to an extremely remote period. Schwalbe believes the Neanderthal type to be quite extinct, and maintains that not a drop of its blood flows in the veins of the human race of to-day. Walkhoff, on the other hand, regards the Neanderthal man as the fundamental form of the Homo recens and the isolated cases of resemblance to the Neanderthal type found among the lower races of man as cases of reversion. The men of the earliest Diluvial Period may have been physically of a very low type, and in mental respects may never have advanced beyond the rudiments of speech, but they were nevertheless men, essentially distinguished from the anthropoids by their superior skull and brain capacity. Homes and Vernau agree that between the Homo antiquus of the Neanderthal type and the Homo antiquus of the later Diluvial Period a race of African origin should be inserted. This race chiefly inhabited the West and South-west of Europe, but was also to be found in the East, and dwelt in caves, or in the open country, possibly protected by screens of brushwood or skins. Remains of their dwellings have been found in France in the caves of Brassempouy, Solutre and Laugerie Haute ; in Belgium in the caves of Pont a Lesse ; in North Italy in the caves of Mentone : in Moravia at Briinn and Predmost, and in Ukraine in the caves in the neighbourhood of Kiev. That men of an African type actually lived in Europe during the Solutre* period is indirectly proved by the ivory figures of steatopygous females such as could only have been made by an African who had had opportunity of observing his fellow- countrymen. In the so-called "Capuchin head " we find the African platyrrhinism, prognathism and retreating chin reproduced with unmistakable clearness. But there are also positive proofs. Both the skeletons from the eighth igneous stratum found in the Grotto of Mentone are almost of pigmy proportions with QUATERNARY MAN 43 elliptic skull, platyrrhine nose, pronounced prognathism and retreating chin. Gaudry (Contribution a Fhistoire des homines fossiles] considers that the Mentone skull resembles the Australian type, especially in the formation of the lower half of the face ; namely, the narrow, elliptical curve of the jaw, the marked prognathism, the narrowness of the lower jaw, and the size and corrugation of the teeth. These characters, however, are also common to the lower African types of man. The human remains from the Austrian loess-deposit point to a low type, though perhaps not quite so low as the Neander- thal type. The femur from the Willendorf loess-deposit is sharply curved and furnished with a very prominent crest, and belonged to an adult of middle height and compact build. The dolichocephalous skull found under the Franz-Joseph Street in Briinn shows a low, coarse brow formation with strongly projecting supra-orbital ridge and retreating fore- head ; the parietal bones have a very slight curve and there is a large gap at the lambdoidal suture. The upper and lower jaw from Predmost have been examined by Walkhoff, who considers that the chin is an improvement on those of the Sipka and Krapina jaws but still in a very backward state of development ; the most striking anthropoid character is the increased tendency towards the formation of enamel on the crowns of the molars. In any case these beings from the loess- deposit, in spite of their low type, must be definitely regarded as human. Vernau sees in the man of the second stage the parent form of the third, and holds the opinion that improved conditions of life led to the gradual change, but so long as proofs are not forthcoming this opinion must remain a mere hypothesis. The third race, belonging to the Madeleine period, shows a decided advance in physical structure, but since we are ignorant as to whether the region was uninterruptedly inhabited, we cannot state with certainty whether these men of improved physical structure descended from those of the second period, or whether they belonged to a distinct type originating else- where. The Madeleine race (called the Cro-Magnon race, from the place of their discovery) must have been superior to the earlier inhabitants of Middle Europe, not only physically but 44 THE HUMAN SPECIES also intellectually, since the skulls found are of large capacity (e.g., skulls from Cro-Magnon have a capacity of from 1,590 to 1,640 ccm.;. The men of this period usually dwelt in caves, but some- times made their homes under projecting rocks or in other protected places. In France we have the Madeleine Stations, Laugerie basse, Les Eyzies, Bruniquet, Mas d'Azil, etc. ; in Switzerland, Kesslerloch ; in Belgium, the Trou de Chateaux ; in Germany, Schussenried, Andernach, and various caves in the Jura Alps, Svvabia (see Fig. 3) ; in Austria, the Gudenus cave and Kulna near Sloup; in Russian Poland, the Maszyck caves. Human remains have been found in Cro-Magnon, FIG. 3. Transverse section of the Hohlefels in Aachtal (Swabia). (Homes.) Laugerie basse, La Chancelade, in the Duruthy cave near Sorde, in the seventh igneous stratum in the Kieder grotto at Mentone, and in the Fiirst-Johanns cave at Cautsch in Moravia. It is probable that the various human remains discovered belong to several different races rather than to any single one ; the French naturalists, Hamy, Dupont, Herve and P. Girod, who agree in regarding the Hyperboreans of the present day, the Tschaktschens, and the Eskimos, as the nearest relatives of the Madeleine cave-dwellers of Western Europe, must be referring solely to those below medium height, to which race the tall, well-grown people of Cro-Magnon surely did not belong. To the pigmy race of the Madeleine period are to be attributed QUATERNARY MAN 45 most probably the small tools of flint, bone and horn, clearly intended for small hands. It was they too who produced the surprisingly faithful drawings of animals on horn and bone so that we involuntarily compare these reindeer hunters with the equally gifted, artistically endowed Eskimos of the present day. In caves of Bohemia (e.g., the Zuzlawitz caves) small, dolichocephalous skulls have been found with very slightly arched parietal bone, and powerful teeth. Now it would be of incalculable value to anthropology if the problem of the physical structure and general appearance of Palaeolithic man could be solved by the portraits of him which he has bequeathed us. But the hope of solution from this quarter cannot be other than illusory. As trustworthy evidence we might perhaps take the circular, ivory female figures of Bras- sempouy,1 for they represent with unmistakable realism steato- pygous females of an inferior African race. On the other hand, the ivory human figure found in the loess-deposit at Briinn would lead us to hazardous conclusions, were we to re- gard it, with its low forehead, projecting brows, broad nose and long chin, as the deliberately designed representative of the race to which the skull belongs found in the same place. The same may be said of the steatopygous figure and the head from the crystalline limestone of Mentone. Moreover, as is seen from Piette's recent investigations in this direction, the possibility of false imitations must be taken into account. One fact, however,, is clearly established by the palaeolithic sketches of the human body, namely, that at that time man went unclothed. (La femme au renne, hunter with bison.) To draw conclusions from the details of the sketches would be as much out of place as to regard our children's attempts at drawing as faithful portraits. How far a naturalist may be led astray by his imagination is shown in the interpretation Piette gives to his latest discoveries in the Mas d'Azil cave. Scratched on the shoulder-blade of an animal is an indistinct drawing, en face, on one side, and on the other a clear sketch, en profit, of a man with strongly marked phallic characters; breast, back, abdomen and nape of the neck are covered with hair, both 1 M. Homes, Urgesch. d. bild. Kunsl in Europa. Wien, 1898 p. 47 and plate ii. 46 THE HUMAN SPECIES arms stretched forward, the right hand apparently holding a wooden club. Now, because the calves and seat are very little developed, and the latter, moreover, is somewhat long, and the face characterised by a very prominent nose, retreating brow and chin, Piette concludes the sketch to represent the Pithecan- thropus erectus, whereas it is obviously only another example of a childishly executed human portrait. As to the descent of Palaeolithic man we are still by no means well informed. We can, certainly, as Homes1 remarks, prove that he existed in various places, but whence he came and his previous manner of existence \ve know not nor can we ascertain it without a "history of his antecedents' antecedents". Broadly speaking, the discoveries of Western Europe permit us to conclude that during the diluvial period several different races existed. Some of the inhabitants of the middle period probably came from Africa originally. But we can form no opinion as to the probable birthplace of Neanderthal man, nor can we state with certainty2 whether the people of the third period, the rein- deer hunters of Cro-Magnon and Laugerie, were of Northern or of Southern origin ; or whether they had developed in Middle Europe from earlier existing forms. As France and Spain were connected with North Africa by an isthmus, during the diluvial period, Homes considers this to have been the source whence Middle Europe received its palaeolithic inhabitants, and he assigns the same part to this " Diluvial Orient " as that played by West Asia in more recent times in connection with Europe. A closer acquaintance with the details of this question is, in the opinion of Homes, only to be obtained by the co-operation of palaeolithic geology and archaeology. European Diluvial Man. Transition from the Palaeolithic to the Neolithic Period. The same doubt and uncertainty that envelops the origin of diluvial man has long surrounded his later fate. Did he simply disappear in order to make room for the newly arrived neolithic man, or was some remnant left that under new influences de- 1 Homes, Der dilnv. Mensch, etc., p. 2. - Homes, he. cit., p. 184. EUROPEAN DILUVIAL MAN 47 veloped and attained to a higher state of culture ? When we consider that in many parts of Europe (Belgium, Switzerland and Austria) a completely new neolithic stratum occurs im- mediately above the palaeolithic, that in others again between the two strata an entirely neutral one occurs, varying in depth, we are justified in rejecting the theory of a gradual transition. Many parts of France, too, by the occurrence of a perfectly neutral stratum between palaeolithic and neolithic go to prove the migration of the reindeer hunters and a subsequent period of abandonment before the advent of a new race. On the other hand, discoveries have been made in parts of North and South France and North Italy whereby a gradual transition from the one period to the other may be traced. In the cave at Mas d'Azil, Piette found the small stone implements of the palaeolithic age, but no sign of the art productions of that time. In- stead there were flat pebbles (see Fig. 4), bearing peculiar signs painted in red, resembling the hieroglyphics of the oldest civilisations. There were no signs of pottery, ground stones, or domestic animals (the usual neolithic characters), the only suggestions of the period being the grains of corn and the rind of stone-fruit. At that time, called by the French the Asylien (Tourassien) Period, the climate must have closely resembled that of the present day, the fauna also being the same. The reindeer had disappeared and the stag had taken its place, and from its antlers the hunters carved harpoons. It is possible that some of the palaeolithic reindeer hunters had remained and now hunted the stag instead. It is not to be assumed, however, that palae- olithic man himself laid the foundations of the later culture of which we find traces in his dwelling-places ; indeed, we are compelled to believe that this culture was due to the influence of strangers who gradually supplanted the old-established popu- lation. Our acquaintance with the physical structure of the man of this transitionary period is very slight, being obtained from the FIG. 4. Red painted pebbles from Mas d'Azil. (Homes.) 48 THE HUMAN SPECIES scanty remains discovered in the South of France and the North of Italy. In the Mas d'Azil cave, Piette found two skele- tons, the flesh of which had been removed with stone implements, and the bones coloured red with oxide of iron. In the " Barma grande," the fifth Grotto of Mentone, lay three skeletons, also coloured red (a full-grown man, a young woman, and a youth) ; the skull formation is dolichocephalous, and similar to that of the Cro-Magnon race. We still need a detailed anatomical description of these skeletons which, judging from the system of burial, all belong to the same race. We have now only to consider the later transitionary period between palaeolithic and neolithic, traces of which have been found chiefly in Italy, France and Denmark ; they occur also in Portugal, Belgium, England, Poland, Finland, in the Ural Mountains, and even in Palestine. This stratum (in France, Campignien ; in Denmark, Kjokkenmoddingen) has been named Mesolithic from the simultaneous occurrence of palaeolithic and neolithic characters therein. The chief meso- lithic characters are : fossil remains of animals, wild and domestic ; barbed arrow-heads of flint with handles ; polished stone axes, and potsherds. The occurrence of palaeolithic together with neolithic characters is most strikingly illustrated in the North- east and South-east of Italy, where the discoveries show a mingling of the two such as can only have been caused by the irresistible advance of a new culture. " Perhaps," says Homes,1 " the native element, pushed ever backward as the superior cul- ture advanced, retreated from the West to the East of Europe, and is responsible for the contents of the ' kitchen middens/ being acquainted with the art of pottery but ignorant of agri- culture and cattle-rearing." Probably the dog was their sole domestic animal. Karl Penka is quite clear as to \vhat race mesolithic men belonged. He believes them to be the descendants of the dolichocephalous, palaeolithic race who on the approach of the Cro-Magnon race followed in the track of the retreating rein- deer and became the progenitors of the fair-haired, blue-eyed Aryans, a theory supported by no proof whatever, there being even no remains of the supposed reindeer forthcoming. 1 Homes, Der dilnv. Mensch, etc.. p. 92. NEOLITHIC MAN 49 In France a human skeleton was discovered in a refuse heap, and numerous skeletons, male and female, differing in age, were brought to light in the mesolithic formation in Portugal (see Fig- 5)- Quatrefages, who examined them, is of the opinion that they represent two races, a dolichocephalous, and a brachycephalous, and assumes that the Atlantic coast was first inhabited by the barbarous, dolichocephalous race, and that the brachycephalous tribes who arrived at a later date were more highly cultivated, possessed stone knives, and gradually mingled with the native race. FIG. 5. Shell-heap at Magern (Portugal) showing the exhumed skeletons. (Homes.) Neolithic Man. Neolithic man, as compared with palaeolithic, had made enormous progress in civilisation. He was no longer dependent on rough-hewn flint tools, though they were still in use. He had acquired the art of grinding and polishing many other kinds of stones which he found in the river-beds ; he fitted them into handles of wood or horn, and could even drill holes in them for the purpose. His well-ground stone axe served him not only as a weapon in hunting, and in war, but was also used for felling trees from which he fashioned his log-canoe, and obtained the beams for 4 50 THE HUMAN SPECIES his hut and material for various wooden utensils. Sometimes he still dwelt in caves, sometimes in the open country in huts of wicker work, pit-houses, or terramaras, or in pile dwellings on the lakes (see Fig. 6). Fish, birds, and the varied produce of the chase — especially venison — formed his food. He had also learnt to domesticate such animals as dogs, oxen, goats, sheep and pigs ; he cleared the forest and tilled the ground and sowed corn (millet, barley and wheat), and was able to appreciate the value of various wild fruits as articles of food. But neolithic FIG. 6. A pile-dwelling. (After Prof. Haberlin.) man possessed yet other advantages over his predecessor. He had acquired two new arts : pottery and plaiting and weaving, both essentially adapted to help forward the work of civilisation. We may safely conclude that these arts were introduced into Europe from elsewhere, discoveries in Egypt having proved that in other continents the dawn of a new day had broken long before the people of Europe had left the Palaeolithic Age behind them. The art of plaiting and weaving flax, and the employ- ment of flax in spinning, must also have been brought from other lands, for in none of the earlier palaeolithic deposits was NEOLITHIC MAN 51 any trace of flax seed or thread ever found. Lastly, the neolithic system of burial also shows a considerable advance ; the dead were no longer buried separately in caves, or in the open fields, but many together in a small room skilfully con- structed of stone, or, as in the Rhine districts, in graveyards arranged in rows, and apart from the country settlements. Specimens of these settlements have also been excavated and they may be described as villages. In the graves the skeletons are found sometimes lying at full length, sometimes in a sitting posture or half-sitting with the knees drawn up to the chin, sometimes lying on the side. The discoveries of neolithic graves prove beyond a doubt that Europe in the neolithic period was not peopled by one uniform race alone, but that the process of division into dolichocephalous and brachycephalous races (the latter of small stature) which began in the palaeolithic period was continued into the next. Remains of a tall, dolichocephalous race have been found in the stone coffins and burial vaults of Sweden, in the cave graves of Aurignac and Duruthy, in the neolithic graveyards on the Rhine, and in the narrow " sitting-graves " of Lengyel (Hungary). A few isolated graves in Sweden contain brachycephalous skeletons of short stature, as do the Aggteleker caves in Hungary and the grottoes of the French Maritime Alps ; the skull of a lake dweller preserved in the Museum at Berne also belongs to a member of the same race. In the dolmens (cromlechs) of France remains of dolichocephalous and brachycephalous individuals were found together — a triumphant proof that the two races were con- temporary. The frequent discoveries of mesocephalous skulls proves that a mingling of the races most certainly took place. In course of time, the dolichocephalous type died out in Europe (with the exception of Scandinavia), being gradually supplanted by the mesocephalous race, till they in their turn were forced into the background by the brachycephalous, which eventually became the predominant European type. 4* PART II. A. Comparative Anatomy and Histology. I. The Bones. IN common with the radiata, mollusca and arthropoda man possesses a skeleton as framework for the muscular tissue, and — __ __ ^j,juj. -• in common with the vertebrata, ??? " - ' .-,.*•• v an inner skeleton, which in the lower fishes and in the early stages of development of the other vertebrates is cartilagin- ous in nature, in the later stages osseous. The bones may be classified as solid, porous and cellular. They contain as inorganic con- stituents basic phosphate of lime together with fluorine, calcium, carbonate of lime, phosphate of magnesia and soluble salt ; as organic, bone, cartilage and fat (see Fig. 7). The number of bones in the human body (see Fig. 8), when the hyoid bone, the sternum and the coccyx are each reckoned as one only, is 223. The human skeleton is so constructed that wherever it corresponds to the animal skeleton it still pos- sesses certain essential differ- ences which render the smallest human bone immediately dis- tinguishable from the corre- 52 FIG. 7. Transverse section of the metacarpal bone : a,, outer sur- face ; b, inner surface ; c, medul- lary canals ; d, lamellae ; e, bone cavities with their ramifications. Highly magnified. (From Thome, Zoologie.) THE BONES 53 spending animal bone. It is the aim of the present work to specify these distinctions and to define the characteristic attri- butes of man. In view of the paramount importance of the skeleton of animals and man it is clear that even the most concise treatise on comparative anatomy demands a relatively large amount of space. The Skull. A skull in the form of a hard capsule made up of several bones, containing the brain, and connected with the facial bones, is possessed solely by the vertebrates. C. Gegenbauer1 has stated with admirable clearness the relation of the human to the animal skull. He says : " The peculiarities of the organisation of the human body are nowhere so significant as in the skull ". When we bear in mind that the formation of the skull in all vertebrates is determined by its relation to the brain, to the organs of sense and to the upper extremity of the intestinal system, the conditions may be formulated as follows : — In all animals, the apes included, the ultimate capacity of the brain is attained much earlier than in man, so that the human skull has a considerably longer period in which to develop for the benefit of the growth of the brain. Gratiolet points out as cause of this fact that in the anthropoid skull the closing of the sutures begins in the frontal region, whereas among the higher races of man it takes place first at the sutura parieto-occipitalis. The lower races of man in this respect re- semble the anthropoids. As regards the cavities in the skull for the reception of the higher organs of sense man is by no means superior to the animals, indeed in the development of certain senses he is their inferior. While the cranium of lower animals ceases early to grow, the facial bones continue to develop until adult age ; this accounts for the preponderant development of the face in all animals up to the anthropoids, as well as for the still greater development of the teeth, and the masticatory muscles, these latter giving rise, in the male, to a bony vertical ridge (see 1 C. Gegenbauer, Lehrbtich der Anatomie, and edition, p. 253. 54 THE HUMAN SPECIES FIG. 8. Human skeleton: a, parietal; b, frontal bone; c, temporal bone; d, upper jaw; e, lower jaw; /, clavicle; g, ribs; h, radius; i, femur; k, patella ; /, tibia; m, tarsal bones; n, metatarsal bones; o, occipital bone; p, seven cervical vertebrae; q, vertebral column; r, scapula; s, humerus ; t, ulna; u, pelvis; v, carpal bones; w, metacarpal bones; x, fingers; y, fibula ; z, toes. THE BONES 55 Figs. 9 and 10). According to Topinard the average capacity of the skull of a Male European = 1400 ccm. Male Gorilla = 498 „ Female Gorilla = 458 „ Male Chimpanzee = 409 „ Female Chimpanzee = 392 „ Male Orang = 426 „ Female Orang = 406 „ FIG. ii. Female Australian. FIG. 12. Microcephalous skull. Skulls of anthropoids and of the lower races of man. (From the Corresp.-Blatt f. Anthrop., Ethnol. und Urgesch. 1877.) Ranke,1 taking the capacity of the skulls of a male and female European (Bavarian) respectively at 1503 and 1325, states it to be an established fact that the absolute cubic content of the female skull is less than that of the male. In all the higher races of man, the inferior height and arch of the female skull, 1 Ranke, Der Mensch, ist edition, i., 293. 56 THE HUMAN SPECIES and the more perpendicular position of the forehead are con- sidered as secondary sexual characters, whereas among the lower races the distinction between male and female is much slighter. The human skull, in addition to its relatively superior size, has other distinctive characters : — On the inner surface of the skull we are struck by the great size of the basal angle and the downward direction of the occipital foramen which in the other vertebrates tends rather backwards. This situation of the occipital foramen gnables the human head to be freely balanced on the vertebral column ; it is caused by the skull and brain being pressed in this direction during an early phase of embryonic development. In all other animals, up to the anthropoids, the frontal half of the skull is FIG. 13. Skull of a newly-born Orang. (From Selenka.) FIG. 14. Skull of a human embyro of ten months. (From Selenka). preponderant, and this has' led to a proportionately greater development of the cervical muscles (see Figs. 13 and 14). In man the inwardly visible basal angle corresponds with the out- wardly visible inclination of the planum nuchae ; this inclines at a sharper angle in man than in animals, a fact due to the greater development of the brain. Hence the higher develop- ment of the frontal lobes in the human brain causes the greater breadth of the interorbital septum and the great size and extent "of the ethmoidal cells. In the ape the frontal lobes are smaller and narrower and the interorbital septum is there- fore narrow, the ethmoidal cells being either entirely absent, or but very slightly developed. The sutura transversa occipitalis, which makes its appear- ance very early in the foetus, sometimes fails to close completely, THE BONES 57 thus giving rise to the so-called Os Incae, and Virchow con- sidered the presence of the Os Incae as the character of a low race ; he also felt compelled to regard as a fixed character of the anthropoids, and the lower races of man, a certain furrow- like depression of the temporal region (sometimes called " temporal strait ") combined with extreme narrowness of the sphenoid bone and the formation of a lepidoid process from the temporal bone direct to the frontal bone. Ranke,1 however, has shown that among civilised races the same phenomenon occurs in a certain percentage of cases. The division of the frontal bone into two parts, which is peculiar to the lower mammals, not only occurs in the embryonic human skull, but is found not seldom in adults, when the two frontal bones are joined by a suture ; this was pointed out by Canestrini in the brachycephalous skulls exhumed from the glacial drift.2 An important difference exists between the arcus supra- orbitalis of the human being (where it is always more pro- nounced in the male than in the female) and that of the anthropoids. In the latter, the prominent supraorbital ridge rests on a massive bone foundation and the frontal cavities are but rudimentary, whereas in man the cavities are highly developed, as may be seen from the skulls of Neander- thal, Spy, Krapina, the Aus- tralian of the present day, many South Sea Islanders, and, indeed, many an inhabi- tant of South Germany. It is the cranium which determines the dimensions of the whole head. The Swedish anatomist, Retzius, was the first to classify the primitive races of Europe as (i) long-headed (dolicho- FIG. 15. Dolichocephalous skull viewed from the side. L, diameter ; r.L, maximum diameter ; GH, height of face ; GL, length of profile ; NL, height of nose ; OH, height of ear. (From the Corr.-Blatt f. Anthrop., etc., 1883.) cephalous). where the diameter from front to back is greater than from side to side, and (2) short-headed (brachycephalous) 1 Ranke, loc. cit., i., 291. 2 Darwin, loc. cit., vol. v., p. 50. 58 THE HUMAN SPECIES where the diameters are almost equal. Now, as each naturalist adopted his own method of measurement the results were very conflicting and unreliable, until the agreement l on crani- ometry was drawn up at Frankfort, whereby the German level was adopted as a basis for future measurements. The level is determined by two straight lines passing through the lowest point in the lower rim of the orbit, and through a point in the upper side of the bony auditory orifice perpendicular to the middle of the cavity of the ear (see Fig. 15). Taking this level as a basis, measurements are made of the diameter, the entire height, the maximum breadth, breadth of the brow, angle of inclination of the occipital foramen, angle of the profile, etc. As we have seen in Part I., two distinct races of man have existed from the most remote times, a dolichocephalous and a brachycephalous, and the intercrossing of these two races in the course of ages has resulted in a third, a meso- cephalous. It must not be supposed, however, that this quality is peculiar to man, for the wild horse of the Palaeolithic Age was divided into two races ; one small, short and broad- headed, the other larger with a long narrow head ; the same dis- tinction is found among the half-wild, half-domesticated cattle of the neolithic pile-dwellers. Proceeding to the face we take first the orbits which belong partly thereto. The lower we descend in the scale of the verte- brates, the more laterally placed are the orbits and the less clearly are they distinguished from the temporal cavities. In man and also in the apes and anthropoids the orbits are situated in the front of the face and are completely closed. The laminae papyraceae which in man aid in forming the orbit are found otherwise only in the apes and in certain armadillos. In the gorilla and chimpanzee, it is true, the orbits are tubular and prominent, but this need not be regarded as an absolute contrast to the conditions of things in man, for the orang also does not possess this bony orbital tube. In certain apes, and other mammals, the upper jaw-bone con- sists of two parts. Now, although in adult man the same bone is generally not so divided as in the two-month-old embryo, the division is found and not seldom remains throughout life, lCorr.-Blatt.f. Anthrop., etc., 1883, vol. i., p. i. THE BONES 59 especially among the low prognathous races, whence Darwin concludes that the division must have been a constant character of the early progenitors of man. Formerly the absence of the in- termaxillary bone, bearing the incisors, ranked as one of the lead- ing distinctive characters of the human face. This bone, which is separated from the canine teeth by a suture was first described by Galen ; later on Vesal, and after him, Peter Camper, Blu- menbach and Sommering dispossessed man of it, judging it to be the peculiar property of the lower animals, until Meckel, and at the same time Goethe, proved it to be a normal formation in man, transitionary and appearing at a very early stage, but constant. Ranke l has definitely cleared up the point (see Fig. 1 6). The sutura incisiva (the suture dividing the back edge of the palate of the two intermaxillary bones from the palate of the upper jaw-bone) is always present in young mammals and only later becomes indistinct, finally disappearing. In the middle of the sutura incisiva is the foramen incisivum. The sutura incisiva may be observed not only in the skull of the newly born but also in adults; indeed, it has been shown that, as Autenrieth supposed, in the human foetus, each of the upper incisors is imbedded in a separate intermaxillary bone, giving rise, accordingly, to a sutura inter- incisiva. Out of 100 skulls from the Munich Collection examined by FIG. 16. Human palate with inter- r> I ... maxillary bones. (Ranke.) Kanke, the sutura incisiva was found in 73 per cent, the sutura interincisiva in 10 per cent. Thus we see that the intermaxillary bone is by no means to be considered a peculiarity of the lower animals, nor are we justi- fied in regarding the divided nasal bone as a specific character of man, as asserted by Wiedersheim,2 for the nasal bone is frequently found divided in other mammals, and though in certain apes it grows together in early youth, the suture re- lCorr.~Blattf. Anthrop., etc., 1901, p. 96. 2 Wiedersheim, R., Dei- Ban desMenschen als Zeugms fur seine Vergangen- heit, Freiburg, 1887, p. 66. 60 THE HUMAN SPECIES mains distinctly visible (e.g., in the genus Cebus). Moreover, Hyrtl has pointed out that in the Hottentot skull the two bones are either partially, or completely, grown together, and this affords sufficient proof that its divided state cannot be peculiar to man. Virchow takes the catarrhine construction of the nose to betoken a low race ; by catarrhine construction is understood that state wherein the nasal bone is not connected with the frontal bone by a more or less broad, transverse sutura, but tapers to an end, as in the gorilla and orang, in the form of small ' narrow laminae generally grown together. This construction of the nasal bone is common among the Malays but is rarely .observed among other nations. In man the lower edge of the nasal cavity generally terminates in a sharp point, called the nasal spine, whereas in the anthropoids the lower edges are blunt and the nasal spine is absent. Exceptions are found, however, among the markedly prognathous European and negro races ; here the edges of the nasal cavity slope gradually away and on either side two low ridges are seen, between which runs a shallow prenasal fossa. The malar bone (cheek-bone), which in the lower mammals is simply a narrow ridge and in the carnivora a wide arch, broadens in man and the apes into a solid arched plate with processes to the temporal and frontal bones and the upper jaw bone ; in the anthropoids, it has a much broader span than in man owing to the greater development of the masticatory muscles. The maxillary joint, the quadrate bone of amphibians, reptiles and birds, is in man as in all the other mammals a temporal joint, and the condyloid process possesses the character of a transverse cylinder. In many mammals the two halves of the lower jaw-bone remain divided throughout life, but they unite into one solid bone in man, in the walrus, sloth, camel, pachydermata, ungulates, bats and apes. In the anthropoids the lower jaw is far more strongly developed than in man, proportionately to their greater masticatory muscles. In all the higher orthognathous races the jaws, upper and lower, form an equilateral triangle, the breadth being to the length as 100 : 100. On the other hand, in all the lower, prognathous races, as well as in the anthropoids, the jaws THE BONES 61 form instead of an equilateral, an isosceles triangle, the sides being greater than the base. Hence the proboscidate character of such skulls. The leading peculiarity of the human jaw, distinguishing it from that of the highest anthropoids, and of all other mam- mals, is the projection in the middle of its exterior surface, the protuberance of the chin. Compared with the most ancient human jaws from the Palaeolithic Age (La Naulette, Sipka, Krapina), the lower jaw of the Homo recens, with its more or less strongly defined chin, has undergone marked improvement. The most varied opinions prevail as to how the formation of the chin and the consequent improvement in the form of the jaw was brought about. Walkhoff assumes that the trajectories of the Musculus digastricus and especially of the M. genio- glossus have been the chief factors in determining the growth of the chin. Weidenreich holds the view that the development of the chin is due to a reduction in the size of the teeth, and of the alveolar edge of the lower jaw, but this is probably erroneous, since, at the present day, man, civilised and uncivilised, possesses a chin in spite of his teeth being almost as large as those of palaeolithic man. Toldt believes the true cause to lie in the development of the form of the head, particularly in the broadening of the frontal part of the skull, which has lead to a corresponding in- crease in the width of the face and of the lower jaw ; in order to relieve the consequently great tension of the lower jaw the bones were strengthened at the point of union of the two halves. This first takes place at the time of birth, appearing as the ossicula mentalia in the median symphysis and forming the starting-point for the structure of the chin. It did not originally exist in the earliest races of man, but has developed gradually in the course of time under the influence of the function it was to perform. Hence, according to Toldt,1 the chin is correlated to the whole structure of the head and is a material advantage possessed by man over all the other animals ; it is, by no means, to be regarded as a sign of weakness or degeneration, which it would be were it traceable to a reduction of the teeth. Another important difference between man and the other JC. Toldt, Vienna, Corr.-Blatt f. Anthropol., etc., 1904, pp. 94-98. 62 THE HUMAN SPECIES mammals, the anthropoids included, lies in the measurements of the skull in profile. This measurement was formerly based on Camper's facial angle, but since the Frankfort agreement it I II in FIG. 17. Development of the Human embryo. (Haeckel, Anthropogenic.) I II III FIG. 18. Development of the Gibbon embryo. (Haeckel, Anthropogenic.) takes, in common with all other craniometrical measurements, the German level as basis. Camper described a horizontal line passing along the base of the nose and orifice of the external auditory canal, and classi- THE BONES 63 fied all skulls according to this line, attaching special importance to the direction of the cheek-bone. He then described at right angles with the horizontal a perpendicular passing down the profile from the highest central point of the brow ; he thus obtained a clear impression of the proboscidate character of the animal skull in comparison with that of man. He arrived at the following results : — In a Macaeus cynomolgus a facial angle of 42° ,, „ young orang-utan „ „ „ „ 58° ,, an adult European „ ,, „ „ 80° But there are human beings possessing a much smaller facial angle ; for instance, the negroes and Kalmucks have a facial angle of 70° owing to the prognathous character of their skulls. Isolated cases of true prognathism in a lesser degree are found in all races, caused by the prominence of the whole upper jaw and the corresponding projection of the lower jaw, but these cases should be care- fully distinguished from the very prevalent alveolar prognathism where only the aveolar process projects. E. Fischer (Freiburg) at a meeting of Anthropologists at Dortmund (1902) l showed conclusively that in spite of the many differences between the human facial angle and that of the apes, they have still much in common in the early phases of embryonic development. Fischer compared the human embryo with the embryo of Macaeus cynomolgus and of Semno- pithecus maurus. That there is a close resemblance between the „ FIG. 19. Gorilla fetus of the size of human skull and that of the apes a human fetus of one to one and in the early embryonic stages ^™onths< Nat size' (Duck has been long admitted, and this refers not only to the anthropoids but also to the lower apes 1 Corr.-Blattfilr Anthrop., etc., 1902, p. 153. 64 THE HUMAN SPECIES whose skulls are strikingly human in appearance in the arch, the relatively slightly developed organ of smell and its probo- scidate character and-in the breadth of the septum interorbitale (see Figs. 17 and 19). The human teeth also possess distinctive characters. In early zoological manuals we find it asserted that man alone possesses an unbroken series of teeth, and that they are all of the same size ; only the first part of this assertion is correct, it being a fact that in man neither is a whole series of teeth absent as in certain other mammals, nor does he possess certain spaces into which the upper and lower canine teeth fit, as in the carnivora, or only the lower canines, as in the apes. As regards the uniform size of the teeth, however, man has in reality no advantage over the other mammals, for, apart from individual differences of size in the molars and incisors, we find signs of a transition stage between the anthropoids and man, both in the molars and canines, there being people in whom the points of the canine teeth are considerably higher than the rest. The milk molars of man and the anthropoids bear a great resemblance to one another, but when we come to the canine teeth the resemblance disappears. Man has shorter and broader permanent molars than have the anthropoids, and the form and height of the molar cusps are constant in man but vary in the different anthropoids. Another human attribute is the lesser divergence of the molar roots (see Fig. 20). In man and in the anthropoids, the upper pre- molars and molars proper have three roots, the lower two ; further, the four cusps of the upper molars are generally the same in man and the anthropoids, but in the Pro- simiae only the first molar has four FIG. 20. Human Teeth. I. Incisor; tt_ ^.1 i_ • u II. Canine ; III. Molar ; (a) CUSPS, the Other two having but crown, (b) root. three each. In man the inner anterior cusp is connected with the outer posterior cusp by means of a ridge and the inner exterior cusp is separated, as it were, from the rest of the tooth by a small furrow. PLATE I. Upper molars of Tertiary apes, later anthropoids and Hottentots. FIG. i, la, ib, 2, aa and 6, Upper molars from the pisolitic iron ore. „ 3 and 33, Upper molars of the Orang. „ 4 and 43, „ ,, ., ,, Gibbon. ,, 5 and 53, ,, ,, ,, a Hottentot. (Wiirtt. Jahreshefte dfs Vereins fur vaterl. Naturkunde, 54 Jahrg., Tafel i.) PLATE II. Lower molars of Tertiary apes, later anthropoids and of man. 2 3 FIG. i, la, 2, za., 4, 4a, 5, 6, 6a, 7, ja., Lower molars from the pisolitic iron ore. ,, 10, Last lower milk premoiar, from the pisolitic iron ore. ,, 3 and 33, Lower molar of the Gibbon. „ 8 and 8a, Lower molar of the Orang. ,, 9, Lower molar of man. (Wiirtt. Jahreshefte des Vereinifiir vaterl. Naturknnde, 54 Jahrg., Tafel ii.) THE BONES 65 The above are the usual figures for the upper molars in man, but there are also races, who have not teeth of a uniform size, in whom the second and third upper molars have three cusps : e.g., the Eskimos and not seldom Americans who are descended from European emigrants. The molars of the lowest races of man (Malays, Australians and negroes) have the highest number of cusps (4, 4, 4) and all these races have besides unusually large teeth. The lower molars in man have normally five, but sometimes six cusps and two roots. It not uncommonly happens, however, that there are only four, three, or two cusps, whereas in the anthropoids far less variation is to be observed. The first and third molars have usually five cusps, but this is subject to modification, especially in the third molar which in most, though not in all, anthropoids is very large, larger indeed than the first or second. Darwin l is of the opinion that the wisdom tooth is tending to become rudimentary among the civilised races, and attributes the fact to the preference for soft food, whereby the posterior part of the alveolar arch has become reduced (Schaaffhausen). In the United States it is said to be of quite common occurrence that children have some of their molars extracted, as the lower jaw is too small to allow of the development of the normal number of teeth. Speaking generally, we may say that the teeth of civilised man stand at one end of the scale, those of the anthropoids at the other, and the negro's midway between. To palaeolithic man eating and chewing were evidently of more importance than speaking. The jaws were longer and contained larger teeth. Since then the tendency to a reduction of the upper and lower jaw — a tendency dating still farther back in man's history — together with the transition from prognathism to orthognism has sensibly increased. As a form of compensa- tion, the jaws have become broader, as Toldt (see above) has shown, and in the lower jaw the chin has been developed.'2 Klaatsch, to whose untiring pen we owe the rehabilitation of the Neanderthal man, and who follows up the very earliest traces of man, regards the human teeth from an original point of view. As in his opinion man by no means stands at the head of all living beings with respect to all parts of his 1 Darwin, loc. cit., v., 257. 2 R. Wiedersheim, he. cit., p. 172. 5 66 THE HUMAN SPECIES organisation, so also he considers that the human teeth are among the most primitive possessed by any of the existing mammals. Had man not sacrificed twelve teeth in the course of his gradual development, he would now have forty-four, the largest number possessed by any land-dwelling mammal. One of the most important points in classifying man in the order of animals is, in the opinion of Klaatsch, the four-cusped human molar. Now as the arctocyon and the Phenacodus (a member of the Ungulata) of the Eocene Period possessed molar teeth which resemble man's as closely as man's resemble those of the anthro- poids, Klaatsch concludes that man, as regards his molar teeth, has not progressed beyond the stage of development reached by the mammals in the Tertiary Period. Further proofs must be produced in connection with other organs of the human body. Wiedersheim l has pointed out that the teeth of the higher vertebrates show interesting signs of reversion. In fishes, amphibians, and certain reptiles the first signs of teeth are epithelial formations which later become absorbed into the mesoderm and form the teeth-ridges, and these develop in due course into the actual teeth. The higher vertebrates have also in the first place similar teeth-ridges but without the pre- liminary formation of papillae. Rose, however, has found that in the human embryo a transitionary formation of rudimentary papillae precedes the formation of the teeth-ridges. Vertebral Column. In the fishes, batrachians, and reptiles, the division of the body into distinct regions is rudimentary, first being perfected in the birds ; the vertebral column in birds, and in mammals, differs conspicuously as to the number of separate vertebrae. Man alone (see Fig. 21) possesses a fixed number of verte- brae. Birds have frequently very numerous cervical and lumbar vertebras, and in mammals the figures are as follows : — 12 to 23 dorsal vertebrae 3 to 7 lumbar vertebras 2 to 5 forming the sacrum 4 to 46 caudal vertebrae 7 cervical vertebrae 1 R. Wiedersheim, loc. cit., p. 172. THE BONES 67 (except in the dugong). Man, on the other hand, has invari- ably 7 cervical, 12 dorsal (very rarely 13), 5 lumbar, 5 composing the sacrum, 4 (very rarely 5) united in the coccyx. The human vertebral column resembles most closely that of the anthropoids. In the orang, gorilla, and chimpanzee, the normal number of thoracic-lumbar vertebrae is 1 6, in the hylobates 18. In exceptional cases the fifth lumbar verte- bra is converted into the first sacral. According to the relative number of his vertebrae, man occupies an intermediate position between the hylobates and the other anthropoids.1 Peculiar to man is the double S-shaped curve of the spine ; according to Cunningham and Huxley there are faint signs of it in the gorilla, but it is entirely absent in all other anthropoids, even in an erect attitude. ( In all mammals the dorsal and lumbar vertebrae are ventrally concave, and in Euro- pean children and the lower races of man (e.g., the Veddahs), the lumbar vertebrae at least are ventrally concave. In the adult of the higher races it is the S-shaped curve which gives the spine its elasticity and enables it to maintain an erect position.2 This divergence from the original type of the Primates is, according to Klaatsch, due to the fact of the lumbar vertebrae being sharply curved against the sacrum, this being caused by the repeated backward pressure of the sacrum FlG in climbing high trees, after the manner of existing wild tribes. Through the peculiar curve of the lumbar spine thus attained, the weight of the head and of the upper part of the trunk was directed so far to the back as to establish the balance necessary for the erect position. On this head the apes may be divided into two groups : the lower apes having the same curve as all other quadrupeds, and the anthropoids in JC. Gegenbauer, lac. cit., i , 175. 2Ranke, loc. cit., i., 351. 5* 21. Human vertebral col- umn in erect position viewed from the right side. (H. Meyer.) 68 THE HUMAN SPECIES the following order : gorilla, orang, chimpanzee and hylobates bearing an increasing resemblance to the curve of the human spine. Another peculiarity possessed by man, in centra-distinction to the apes, is that the spinous processes of all human cervical vertebrae branch out into two points ; this does not occur in any other Primate, and in the chimpanzee only at the second and third cervical vertebra (see Figs. 22 and 23). Moreover in the chimpanzee, gorilla and orang, the spinal processes are much longer than in man. Of phylogenetic importance is the perforation of the transverse processes of the cervical verte- brae giving them the appearance of two processes joined to- gether, of which the anterior ones (from the point of view of comparative ana- tomy) must be re- garded as rudiment- -Venal cavity ary cervical ribs. ' "Condyioid process The neck with its covering of flesh and muscle is a further characteristic attri- bute of man. It rises freely above the shoulders, is cylindrical in the neighbourhood of the head, becoming broader towards the thorax, and is curved, back and front, where it joins the head. It forms another distinction between man and the anthropoids, for in the latter the neck is by no means free, the head hangs forward on the breast, sunk between the shoulders as in a human being deformed by rickets. The ligamentum nuchas is considerably less de- veloped in man than in the other mammals. Schwalbe has found that in the cervical ligament of the ruminants the elastic filaments are arranged like cords inside which they Odontoid peg Condyloid process Venal cavity Condyloid process FIG. 22. Episterpheus (front view). FIG. 23. Fifth cervical vertebra (viewed from underneath). THE BONES 69 are connected with one another by means of well-defined anastomoses. Thorax. The barrel-like form of the human thorax is due to the erect position (see Fig. 24). The thorax was originally keel- shaped and is so still in all those mammals who support the weight of the body on all four extremities (pachyderms, beasts of prey, ruminants, equidae), the barrel-shaped form being a later development in man and in all mammals the weight of whose bodies is supported by water, by air, or by the posterior extremities (marsupials, rodents, in- sectivora, cetaceans, ot- ters, sea-otters, bats and anthropoids). That the barrel form has been evolved from the keel form can be proved, onto- genetically and phylo- genetically. The deter- mining factor in the transformation of the thorax in the Primates was the gradual conver- sion of the anterior ex- tremities into organs of prehension, with their great muscular development. This form of the thorax causes the centre of gravity to be transferred to the back, thus facilitating the adoption of the erect position.1 Man in common with the orang has normally twelve ribs, the gorilla and chimpanzee have thirteen, the hylobates fourteen. As Wiedersheim * states so emphatically, the history of evolu- tion has shown that man's progenitors must have had a greater number of ribs, and it is a fact that a thirteenth rib is present in the human embiyo ; it disappears later on, though in exceptional cases it continues to develop. Traces of super- numerary ribs have been found in the region of the lumbar 1 Wiedersheim, loc. cit., pp. 39-41. "Ibid., p. 42. FIG. 24. The Human Thorax. B, sternum ; Sb, scapula. 70 THE HUMAN SPECIES vertebrae, and it is not uncommon to meet with cervical ribs proceeding from the last cervical vertebra. The sternum, or breast-bone, which, it must be remembered, in our early progenitors consisted of a series of consecutive parts, in all mammals, may be divided into three parts : hilt, blade and ensiform process ; but in man, as in the rest of the Primates, it forms a uniformly broad, compact plate. The interarticular cartilages correspond to the lateral parts of the episternum of the other mammals.1 The clavicle, or collar-bone, is developed in the same way as in the mammals which employ the upper limbs for grasping, scratching, flying, climbing or striking. The human clavicle corresponds most closely in its development to that of the apes and bats. A masterly and exhaustive treatise on the scapula has been issued by Ranke.2 In the quadrupedal mammals the scapula forms the point of support for the upper limbs and consists of a long, almost triangular bony plate with a relatively deep cup- like cavity (the glenoid cavity) at its outer angle. Into this cavity the head of the humerus fits, producing thereby an almost perpendicular upward pressure. The surface modelling of the shoulder-blade is modified, on the one hand, by the mechanical action of supporting the arm, and, on the other hand, to an important degree by the muscles. The shoulder-blade is further strengthened by the thickening of the edges converging towards the glenoid cavity, and also by the spine of the scapula, which in many mammals (e.g., the carni- vora) runs midway between the two edges of the scapula towards the glenoid cavity. The spine of the scapula indicates the direction of the main pressure, forms the chief support and is situated perpendicularly to the middle of the joint (Figs. 25-31). The closest resem- blance to the human shoulder-blade is found in the orang, gorilla, and chimpanzee ; that of the hylobates is intermediate between the anthropoids and the cynocephalous apes. The anthropoid scapula differs from the human in the following respects (p. 71). The incisura scapulas is absent. The posterior border of the human scapula takes a downward perpendicular 1 Wiedersheim, loc.cit., p. 49. *Corr.-Blattf. Anthrop., 1904, p. 139. THE BONES direction ; in the anthropoid it describes a curve from the upper exterior edge to the lower interior. The basal line of the spine, described from the posterior edge of the scapula to the lower edge of the glenoid cavity, forms with the posterior border : in man a right angle; in the orang an angle of 120°. The angle of the scapula in the anthropoids corresponds to their semi-erect position. The articular cavity differs also in form and depth in man and the anthropoids. In the orang it is comparatively deeper and narrower. In man, the surface of the cavity is kidney-shaped, in the orang purse-shaped. In man, the humerus possesses a far greater power of rotatory Collection of scapula. (Ranke.) FIG. 25. FIG. 26. FIG. 27. FIG. 28. FIG. 29. FIG. 30. FIG. 31. 25. Man. 26. Gorilla. 27. Chimpanzee. 28. Orang. 29. Hylobates. 30. Dog. 31. Stag. (Corr.-Blatt f. Anthrop., etc., 1904, 141.) motion. In man, the surface of the cavity is nearly parallel with the outer edge of the scapula ; in the anthropoids the angle of inclination is 45° = £ R. The chief difference between the human scapula and that of the gorilla, which resembles man's more closely than does that of the orang, is that the spine cuts the outer edge at a much lower point in the gorilla than in man. The incisura scapulae is absent in the gorilla as in all the other anthropoids. The chimpanzee has a consider- ably narrower shoulder-blade than has the orang, gorilla, or man, though in outline it shows many points of similarity to the human scapula. It is clear at a glance that the scapula of the hylobates possesses very little human resemblance, as it is 72 THE HUMAN SPECIES extremely narrow and is divided into two almost equal parts by the spine (similarly to the scapula of the carnivora) ; indeed in many respects the scapula of the hylobates is even less human in character than that of the semi-apes, particularly the Indri of Madagascar. Among the mammals, however, with the exception of the anthropoids, the scapula of the bat most closely resembles that of man. The fossa supraspinalis is small, the fossa infraspinalis much larger. Like man, the bat uses the upper extremities only to a very slight degree as organs of support. Man's broad, flat back is one of his most distinctive char- acters, and no less important is the form of the trunk, which somewhat resembles an hour glass, thus causing the abdominal organs to be entirely supported by the pelvis. The pressure of the intestines caused by the erect position has resulted in that transverse broadening of the iliac bones, which, contrasted with the narrow pelvis of the anthropoids, is so distinctive a human character, and in the human female has been still more increased through sexual adaptation.1 This sexual difference in the human pelvis (see Figs. 32 and 33) is a specific human character ; in the lower races of man the difference is less strongly developed. Wiedersheim '2 states the case with admirable clearness, showing that in the human being the pressure of the uterus during pregnancy is sagittally directed and not ventrally as in the other mammals. The uterus is supported by the iliac bones. It has further been shown by Wiedersheim that the number of vertebrae above the sacrum was originally greater, that the pelvis was situated more towards the back and that the forward tendency still persists. This is proved by cases where the fifth and even the fourth lumbar vertebra has joined the sacrum similarly to the case of the orang, chimpanzee and gorilla. In man the coccyx generally consists of four, in rare cases of five, vertebras, in all of which, with the exception of the uppermost one, the true vertebrate form is rudimentary. More than five coccygeal vertebrae have never been observed in man, even in the embryo. The absence of a tail is no distinctive character of man, for 1 Wiedersheim, loc. cit., p. 41. z Ibid., p. 86. THE BONES 73 there are tailless animals in other orders, and the backward curve of the coccygeal vertebras (named by Waldeyer " inner tail " or cauda occultd) is shared by the tailless anthropoids. Embryological research has proved that the early progenitors of man, and the anthropoids, undoubtedly had outer tails. The human embryo of from four to six cm. has a real tail outwardly visible and projecting, with segments, medullary canal and caudal intestine.1 The spot where the point of the os Sacrum Acetabulum Suture of the pubic bone Cavity of the hij Hip-bone FIG. 32. Male pelvis. (Ranke, D. M.) Sacrum Iliac bone Ligament Coccyx Hip-bone jmif ^^gpr^ Suture of pubic bone FIG. 33. Female pelvis. (Ranke, D. M.) coccygis presses outwards against the skin, where formerly the tail actually passed through before the subsequent curving of the sacrum, is indicated in the embryo by the vertex coccygeus. As the time of birth approaches, this vertebra disappears and is replaced by a smooth hairless spot (glabella coccygea) which often assumes the form of a small depression (foveola coccygea).2 1 Wiedersheim, loc. cit., p. 27. 2 Ibid., p. 7. 74 THE HUMAN SPECIES To enter more thoroughly into the distinctions between the human pelvis and that of the apes we cannot do better than quote the definition of the same as formulated by Albrecht,1 " Man alone possesses a fossa iliaca interna". In the apes the superficies iliaca interna is more or less convex, the fossa interna in man being due to the pressure of the intestines caused by the erect position. Similarly, in man alone is the anterior section of the superficies iliaca externa convex. Again, only man and not one of the apes possesses a spina superior anterior ossis ilei projecting above the incisura inter- spinalis anterior, and of all the Primates he has relatively the smallest space between the superior and inferior anterior spines. When we consider further that man possesses the smallest space between the cornu posterius acetabuli and the tuber ischii, and that the dorsal surface of the symphysis is con- vex in man, and concave in all apes, we have sufficient proof that the erect position of man has led to marked modifications of the pelvis. To Ranke 2 we owe the formulation of still another dis- tinction between the human and anthropoid skeletons, namely, the relation of the trunk to the entire stature and to .the length of the leg. Taking the stature at 100, the length of the trunk is :• — - In the male gorilla . . . 50*40 „ chimpanzee . . . 44/80 „ orang-utan . . . 44'5O „ pure negro . . . 36*98 ,, German . . . 36*27 Hence in man the trunk is shorter than in the anthropoids. We may now consider the proportion of the trunk to the leg. Taking again the stature at 100, we obtain the following figures: — A South German is to a gorilla as 1 346 : 69^2 ,, „ to a chimpanzee as 1346 : 78*5 „ ,, to an orang as 1346 : 78 Hence in man the leg is longer than the trunk, in the anthro- poids shorter. ^Corr.-Blattf. Anthrop., etc., 1883, p. 100. 2 Ranke, loc. cit., ii., p. 7. THE BONES 75 Extremities. Next in importance to the head and vertebral column, as regards distinctive human characters, come the extremities. In the first place, the head of the humerus differs widely from that of the anthropoids and other mammals. The head of the human humerus is almost a perfect segment of a sphere ; that of the gorilla, according to Aeby, is like a transversely placed cycloid. In mammals, as a rule, the articular cavity of the scapula is placed downwards, in man it has an outward direction. In the quadrupeds, the head of the humerus during walking is pressed into the joint ; in man, the head is free, thus rendering a backward and forward rotatory motion possible, in addition to the up and down motion. Another distinctive character of man is the length of the humerus, which in the human body is shorter, but in the anthropoid longer than the femur. Man in his more highly developed state is further distinguished from the anthropoids by the shortness of the fore- arm in proportion to the upper arm (see Fig. 34). According to Wiedersheim, taking the humerus at 100, the length of the radius is as follows :— In the European . . . -'73 Aino . . 77-4 Veddah .... 80 „ Chimpanzee .... 90^94 In the gibbon the forearm even exceeds the upper arm in length, and to this the fact is due that in an erect position the finger- tips touch the ground. The perforation of the fossa olecrani, peculiar to the anthropoids and lower apes, occurs very seldom in the higher races of man, but its absence cannot rank as an absolutely distinctive character, since it is frequently observed in the lower races (S. Africans, Veddahs) and occurs in pre- historic skeletons. " In man the fore-foot, fitted exclusively into the radius and thus rendered movable, has developed into the hand" (Pfitzer). The rare cases where an articulatio ulno- carpea occurs (i.e., where the ulna is connected with the tra- pezium and pisiform) must be regarded as cases of atavism.1 In man the os centrale, which appears in the embryo, 1 Wiedersheim, loc. cit., p. 85. 76 THE HUMAN SPECIES unites with the os naviculare in the second half of the third month, whereas in the orang and the majority of the other apes, it occurs regularly as an independent bone and is absent only in the gorilla and chimpanzee. With respect to the evolution of the human hand, Darwin believes it to have been brought O about in accordance with the principle of the divi- sion of labour, in propor- tion as the hands were perfected for prehension the feet became adapted for support and progres- sion. Klaatsch, however, asserts that in the Eocene Period even the carni- vora possessed a hand with an opposable thumb, very similar to the hu- man hand, and that later a reversion of the hand to a claw took place. Thus in Klaatsch's l opinion the human hand has not been evolved from the foot of a quad- rupedal progenitor ; it is no new acquisition nor is it the peculiar property of man, but a very ancient heritage from the re- mote ancestors of man and the mammals. From the earliest times the hand has held an important place in the development of the land vertebrates owing to the opposable thumb. 1 Corr.-Blatt f. Anthrop., 1901, p. 102. Ill FIG. 34. Arm and hand of three anthropoids. I. Chimpanzee. Il.Veddah. III. European (Mediterranean). (From Haeckel, Anthro- pogenic.) THE BONES 77 The prototype of the carnivora (arctocyon) like the pro- totype of the ungulates (phenacodus) had a hand which closely resembled that of the prosimiae and primates of the present day. When the human hand is compared with the hand of an anthropoid many points of difference may be observed. Man alone possesses a perfect hand fitted for the most delicate uses. The hand of the highest anthropoid, the gorilla, is broad and clumsy, and, in the opinion of R. Hartmann, is more like a lion's paw. The length of the palm is considerable, but the fingers only become independent from the middle of the first phalanx ; between the third and fourth fingers the skin is continued almost to the second phalanx. The dorsal surface of all the fingers is convex.1 In the chimpanzee also the four fingers are connected with each other by a membrane which sometimes extends as far as the joints between the first and second phalanges. As in the gorilla, the horny skin of the palm is furrowed with countless wrinkles, and the gorilla has numerous small callosities deeply imbedded in the lines of the hand. Another of the typical features of man is the thumb, sur- passing as it does in length and anatomical structure the thumb of even the highest anthropoids. In man the thumb extends as far as, or even past, the middle of the first phalanx of the index finger. In the gorilla it reaches but a short way beyond the base of the first phalanx of the index finger, while in the chimpanzee and other anthropoids it is still shorter. The human thumb alone has remained stationary throughout the ages and has thus not increased in perfection. In all the apes, without exception, the thumb has undergone retrograde changes, so that the hand, even of the gorilla and the gibbon, is no longer a perfect organ of prehension. In all apes the index finger is shorter than the third finger, though, it must be admitted, cases are sometimes found in man betraying very similar ape- like conditions. Distinctively human is the power of bending the hand so as to form a kind of scoop, and the power of completely encircling a ball (suited to the size of the hand) with the curved fingers (A. Ecker). In his book Ranke 2 advances several points, of 1 Ranke, loc. cit., ii., pp. 15, 24. zlbid., p. 7. 78 THE HUMAN SPECIES great value in comparing the upper limbs of man with those of the anthropoids. Taking the stature at 100, the length of the arm together with the hand is : — In the gorilla . . . 64*9 ,, „ chimpanzee . . 67'6/ „ „ orang . . 8072 „ man . 45-16-45-43 Again, given the stature at 100, the length of the hand is :— In man . . . . i r6 „ the gorilla . . 17-4 „ „ orang . .22 „ „ chimpanzee . -23 Hence we see that relatively to his stature man has the shortest arm and the shortest hand. No less striking and equally valuable as distinctive characters are the differences between the lower extremities. With re- spect to the human femur it is much longer than the anthro- poid, and is much more extended in the hip-joint (see Figs. 35 and 36). The trochanter tertius for the insertion of the muse, gluteus maximus is absent in the anthropoids, but it cannot be regarded as peculiar to man since it is found also in the horse, ass, rhinoceros, tapir, certain rodents, and some other mammals. Moreover the trochanter tertius is not uniform in all races of man, being more markedly developed in the higher races, though, strange to say, it is to be found even in the man of the reindeer period,1 in whom also the characteristic curve of the shaft of the femur was already present. The femur discovered by Dubois in Java, which gave rise to so much discussion as to whether it had belonged to a man, or an ape, or to some inter- mediate being, led to the inevitable inquiry as to what con- stituted the distinctive signs of the human femur anatomically and histologically. In the following paragraph I give Bumtiller's (Das Menschliche Femur, Inaug.-Dissertat., Augsburg) definition of the differences between the human and anthropoid femur (hylobates excepted). The human femur is not only longer but thinner and more 1 Houze, " Le troisieme trochanter de 1'homme et des animaux ". Bulletin Soc, Anthr. de Belgique, Bruxelles, 1893. THE BONES 79 slender than the anthropoid femur. The transverse section of the diaphysis is in man triangular, in the anthropoids a broad, Human Skeleton. Skeleton of a Gorilla. FIG. 35- Man. FIG. 36. Giant gorilla. (From Haeckel, Anthropogenic). sagittally compressed oval ; the popliteal transverse section is in the anthropoid much broader and lower than in man. The differences in the condyles is very striking : in man 8o THE HUMAN SPECIES the lateral condyle is usually the longer and the median is apparently rudimentary, whereas in the anthropoid the condi- tions are exactly the reverse. The human femur is usually sharply bent at the top, but in the anthropoid femur the curve is slight and occurs sometimes at the lower end. The anthro- poid radii of the lateral knee ligaments are exactly the opposite of the human. This rough anatomical sketch may be followed by Professor WalkhofFs1 " Studien iiber die Entwicklungs- mechanik des Primaten-Skelets," which open with a differential diagnosis of the human femur as compared with the anthropoid. Walkhoff combined with his studies the application of the Rontgen rays, and found, as Culmann and H. Meyer had done before, that the femoral spongiosa corresponds, in its tractive curves and curves of pressure, to the structure of a crane. Now in man, according to Walkhoff, the bony crest which extends from the inner angle of the neck of the femur along the inner side of the bone and through the head is quantitatively by far the most important and is proportioned to the great pressure borne by this part of the limb in standing and walking. The anthropoid femur does not possess this trajectorium ; its spongiosa is coarser and its cells circular. Another characteristic attribute of man is the great extensi- bility of the knee-joint which has been of the first importance in enabling man to adopt the erect position. The platycnemia of the tibia peculiar to all anthropoids, with the exception of the orang, is only found in the lower races of man as may be seen from the prehistoric tibiae. A similar case is that of the retroversio tibiae, a retroverse position of the upper surface of the tibial joint. This may always be observed, as the investi- gations of Wiedersheim show, in the human embryo from the third month onwards; it disappears in the sixth or seventh month in children of the Caucasian race, but in the lower races remains and is to be seen in prehistoric skeletons. The fibula of man, during the earlier phases of embryonic development, is connected with the femur together with the tibia. But the weight of the body having been gradually trans- ferred to the tibia alone the fibula slipped, as it were, down to lCorr.-Blattf. Anthrop., 1904, p. 73. THE BONES 81 the tibia itself. Hence in man the tibial malleolus gains the ascendancy over the fibular and remains predominant. By means of the two malleoli, the astragalus and os calcis are held as in a vice in the same line with the tibia. Markedly developed in man is the os calcis (heel) for the reception of the important tendon of Achilles. The arched formation of the foot, which occurs only in man, causes the weight of the body to be supported by the heel and the balls of the great toe and small toe. The arched foot is incompatible with the free movement of the great toe, possessed by the apes (A. Ecker). In man the great toe together with its metatarsal bone is strongly developed, the other toes being quite short. In certain lower races (Veddahs, Australians), the great toe forms a kind of organ of prehension similar to that of the apes, but in all the higher races the power of prehension has been lost ; the great toe is an organ of support, the whole foot is a foot adapted for support. On examining the foot of an anthropoid, e.g., that of a gorilla, we are struck by the essential differential characters. Here the great toe diverges from the longitudinal axis of the foot at an angle of 60°. The opposability of the great toe is shown by a furrow running lengthwise along the sole. Besides this there are transverse furrows revealing still more clearly the resemblance of the gorilla foot to the human hand. The other toes are relatively small and slender, and are connected together by a membrane which extends as far as the base of the second phalanx.1 Wiedersheim 2 has briefly summed up the character- istic attributes of the human foot as compared with the anthro- poid : — (1) More complete development of the great toe ; (2) Reduction of the length of the toes owing to their having lost the power of prehension ; (3) Fuller development of all the tarsal bones ; (4) Parallel position of the axis of the great toe with respect to those of the other toes ; (5) Greater breadth ; (6) More pronounced arch formation. That the length of radii is absolutely, and relatively, greater , loc. cit., ii.. 16. 2 Wiedersheim, loc. cit., p. 95. 6 82 THE HUMAN SPECIES in man than in woman must be considered as a sexual character attained in the course of man's progress. The human foot is perfectly adapted for support, and as such forms one of the most distinctive characters of the human body. But all anatomists unanimously agree that it was not originally an organ of support but of prehension as it still is in the apes. This view is most vigorously upheld by Klaatsch, the Heidelberg naturalist. The human foot is to be traced to the same original form as is that of the other Primates ; even the fossil remains of the Tertiary Period show that the mammals already possessed a foot with the Primate character of an oppos- able great toe. In the opinion of Klaatsch, it is clear that the human foot was originally adapted to semi-erect climbing, and that at a later period when man's progenitors had attained the human state, and lived in scattered groups, the adoption of the erect position necessarily involved an adjustment of the foot to the new conditions. That man's ancestors did undoubtedly possess a prehensile foot is irrefutably proved by embryology. In a human embryo of about one inch in length examined by Wyman l the great toe was shorter than the others, and, instead of being parallel with them, projected at an angle from the side of the foot, thus corresponding with the condition of this part in the quadrumana. Hence Darwin concludes that the foot belonging to man's prototype was prehensile, and that our early progenitors without doubt led an arboreal life in some warm, forest-clad land. If they were from the beginning semi- erect, their mode of progression was probably similar to that of the orang, who swings his body forward with bent knees and rests on the outer margin and knuckles of the bent hands. In conclusion I may quote some comparative tables from Ranke's 2 work, showing the relative lengths of the upper and lower extremities in man and the anthropoids. Taking the stature at 100, the length of the leg is :— In the gorilla . . . 34/9 „ „ orang 3472 „ „ chimpanzee . . . 3 5 '20 „ man . . 48-47-48-83 The arm together with the hand is in man shorter, in the 1 Darwin, loc. cit., vol. v., p. 14. 2Ranke, loc. cit., vol. ii., p. 7. MUSCULAR SYSTEM 83 anthropoid longer, than the leg. The forearm in man is shorter, in the anthropoid longer, than the tibia. Again taking the stature at 100, the length of the foot is :— In man . . . . . 14-5 ,, the gorilla .... 20^4 „ „ chimpanzee . . . 2O'5 „ „ orang 25-5 Hence man relatively to his stature has not only a smaller hand but also a smaller foot than the anthropoids. II. Muscular System. Before proceeding to the comparison of the muscles of man with those of animals we cannot do better than again quote Gegenbauer's l words : " In the physical structure of man there is no justification for assuming a fundamental difference. In the construction of the human body we meet with far more than mere resemblances to the organisation of animals ; we find indeed a great and manifold correspondence in all those organs which perform the same functions. This correspond- ence extends to the most minute structural details. Absolute uniformity of all parts is not to be expected, since it is not found even among closely related animals." Gegenbauer goes on to treat of various characters of the human organism which are either present in a rudimentary state or are entirely absent, and points out that this is not necessarily a loss, since the rudiment- ary structures are not only made good by compensation but even open the way for new forms possibly of greater value to the organism, thus helping towards its ultimate perfection. Of special interest, viewed from this standpoint, are the conclusions given by Wiedersheim (see below) in his frequently mentioned book on the regressive and progressive muscles of man. The number of muscles proper to man (including those whose several origins bear special names) is : — In man 316 paired and 7 single „ woman 315 „ „ 8 „ As was to be expected, the human muscles, both the striate 1 Gegenbauer, Lehrbuch d. Anat. d. Menscfi., vol. i., p. 33. 6* 84 THE HUMAN SPECIES and the non-striate, possess histological peculiarities. The striate muscular fibres in man are 20^40 mm. long with an average diameter of '06 mm. ; those of animals have a diameter of •Ooi-'Oo8 mm. The non-striate muscles of man are '045 - '225 long, '004 - •007 wide; of animals, "OO2 - '009 long, '007 -'015 wide. It should further be observed that the muscles of certain mammals are not uniformly red, but appear more or less pale in some groups. The pale muscles exhibit distinct transverse striae but almost indistinct longitudinal striae, while the red muscles show exactly the opposite conditions (rabbit, guinea-pig). The gradual predominance of the red over the white muscles may be traced from the fishes up to the mammals. Birds may be divided into graminivorous with white muscles and carnivorous with red muscles. Wiedersheim,1 who has made a special study of the comparative anatomy of the muscles of man and the mammals, divides the human muscles with their extraordin- ary variability into three main groups : — (1) Regressive, rudimentary. (2) Rare, atavistic. (3) Progressive. Among the regressive, or rudimentary, the cutaneous muscles must first be mentioned, as in man — and occasionally also in the anthropoids — only enfeebled remnants thereof occur. The cutaneous muscle of the neck has shrunk into one with the platysma myoides, the tendinous galea aponeurotica has been developed at the cost of a part of the muse, occipitalis, and of the muse, epicraneus, the muscle which moves the scalp, only the m. frontalis (the corrugator of the brow) is properly developed (see Fig. 37, a). In rare cases the m. epicraneus persists in man together with the power of freely moving the scalp up and down. Rudimentary also, with rare exceptions, are the muscles which serve to move the external ear, the m. attrahens, m. retrahens and m. attollens auriculas (see Fig. 38). The smaller intrinsic muscles of the ear have entirely lost the power of voluntary movement. The fascia axillaris may be considered as a rudiment of 1 Wiedersheim, loc. cit., p. 125. MUSCULAR SYSTEM the panniculus carnosus of the mammals. According to Langer, the fascia axillaris divides at the outer wall of the axilla into FIG. 37. Muscles of the head and neck, a, m. frontalis; b, m. sphinct. palpebrarum ; c, levator palp. sup. ; e, levator labii super, alaeque nasi ; /, depressor nasi; g, levator labii prop.; k, orbicularis oris; /, depressor lab. inf.; m, depressor oris; n, m. mastic.; o, buccinator; p, m. tem- poralis ; q, m. occipitalis ; r, m. styl. hyoid. ; s, m. digastricus ; t, do. ; h, risorius min. ; i, risorius maj. (Thome".) two branches which unite in the fascia brachialis. They may be considered as to- gether forming a fibrous crescent-shaped arch, con- cave in the direction of the arm. Langer also met with cases where muscular fasci- culi, following a compara- tively independent course, crossed the axilla and formed a fleshy, connecting bridge between the edge of the m. latissimus dorsi and the lower surface of the m. pectoralis major. English and French anatomists apply the name fascia FIG. 38. Rudimentary muscles of the hu- man ear. (Haeckel.) a, m. attollens ; b, m. attrahens ; c, m. retrahens; d, m. helicis maj. ; e, m. helicis min. ; f, m. tragicus ; g, m. antitragicus. 86 THE HUMAN SPECIES axillaris to this anomalous muscle which is but loosely connected with the fascia proper. Hyrtl and others held it to be an aberration of the m. lat. dorsi. Comparative anatomy, however, supplies the explanation. As early as 1867, Turner declared the fascia axillaris to be a rudiment of the panniculus carnosus of the mammals. M. pect. maj. M. pect. min. Fascia axillaris — Inscript. tend. M. latiss. dorsi FIG. 39. Muscles of the human axilla (thorax from the side). The Fascia Axillaris of Man.) I natural size (Ludwig Tobler, The higher we proceed in the scale of the mammals the more rudimentary do we find the cutaneous muscles. They are highly developed in the monotremata and marsupials, but show signs of retrogression in the lower Primates. Speaking generally, the whole group of the anthropoids has lost the fascia axillaris and indeed every vestige of a cutaneous muscular system. The gorilla, on the other hand, possesses certain points MUSCULAR SYSTEM of resemblance to man. Normal structures of certain of the other Primates occur in man as fairly frequent variations (see Fig- 39)- In man, as in the Primates and gorilla, we sometimes find a flat, triangular muscle extending from the m. lat. dorsi through the axilla to the m. pectoralis maj., supplied in the great majority of cases by branches of the plexus brachialis.1 Other rudimentary muscles in man and the anthropoids are M. masseter M. styloglossus M. digastricus — M. stylohyoid M. splenius cap. M . sternocleidomastoid M. levat. scap. M. scalen. post. M. omohyoideus M. mylohyoideus M. disgastricus M. hyoglossus M. thyreopharyngeus M. omohyoideus Glandul. thyroidea M. sternohyoideus M. sterno-thyreoiders M. steonocleidcmast Pars ftemalis Pars clavicularis Anterior scalene fossa M. scalenus anter. Posterior scalene fossa M. scalenus medius FIG. 40. Anterior muscles of the human neck. (Heitzmann-Zuckerkandl.) the m. palmaris and m. plantaris, and still more regressive are the mm. interossei pedis, which are divided into plantares and dorsales. In certain phases of the embryonic development they are still plantar as they are in the apes and in most of the lower mammals. The change to the dorsal position, as illus- trated in man, and to a lesser degree in the orang and inuus, determines the retrograde metamorphosis of these muscles. 1 Ludwig Tobler, Inaug. Dissert., Leipzig, 1902. THE HUMAN SPECIES Regressive muscles in the human trunk are the musculi scaleni (see Fig. 40), and the m. triangularis sterni, the m. rectus abdominis (see Fig. 41) and pyramidalis, the vertebral and dorsally situated remnants of those muscles which in the caudate mammals serve to move the tail. Occasionally in man the m. caudo-femoralis is still found, a muscle which plays a great part in many of the caudate mammals. All the remaining caudal muscles of the mam- mals are to a greater or lesser degree de- generate in man, and the m. levator ani (or diaphragma pelvis) in man, and the anthro- poids, must be con- sidered as a remnant of the m. pubo-coccygeus and ileo-coccygeus. Darwin has drawn attention to numerous muscles of the human arm and hand which show a strong tendency to vary so as to re- semble the correspond- ing musclesin the lower animals. He attributes these variations to re- version (atavism), and in support of his opinion refers to the views of Wood, who con- siders that notable departures from the ordinary type of the muscular structures run in grooves or directions, which must be taken to indicate some unknown factor, which is of much im- portance to a comprehensive knowledge of general and scientific anatomy. Indeed, many a remarkable variation in the human muscles is only to be understood when regarded as a remnant of a FIG. 41. M. rectus abdominis. (Heitzmann-Zuckerkandl.) MUSCULAR SYSTEM 89 former state of existence. Wiedersheim l includes among the atavistic muscles the m. cleido-occipitalis between the m. trape- zius and sterno-cleido-mastoideus; the m. latissimo-condyloideus, an appendage of the m. latissimus dorsi, very rare in man, but constant in all anthropoids ; the m. epitrochleo-anconeus ; the levator claviculae, and the glutaeus quartus (ischio-femoralis). Klaatsch regards the short head of the m. biceps femoris as atavistic in the strictest sense of the term (see Fig. 42). In man the long head of this muscle proceeds from the tuber ossis ischii united with the m. semi-tendinosus, but the short head springs from the middle region of the posterior femoral surface, directly from the linea aspera. Now, as this muscle, which is possessed only by man, the anthropoids and the American pre- hensile-tailed monkeys, had originally no connection with the long head of the m. biceps which is supplied by the nerv. tibialis, but belonged to the glutaei and was innervated by the nervus peroneus, Klaatsch thinks it to be a remnant from the period when the ancestors of the lower mammals more closely resembled the Primates. According to Professor Eisler of Halle, the short head of the biceps finds its homologue in the other mammals in the m, tenuissimus, a muscle springing from the caudal vertebrae, or from the gluteal fascia and inserted into the fascia at the distal third of the tibia. This muscle is well developed in the carni- vora, in certain marsupials, rodents and insectivora, as well as in all the lower apes of the Old World. To the progressive muscles of man belong most of the facial muscles of mimicry, such as the m. frontalis, and especially those surrounding the eye, and the orifices of the mouth and nose, as well as those placed below the cheekbone, namely, the corrugator supercilii, orbicularis palpebrarum, pyramidalis nasi, levator labii superioris alaeque nasi, levator labii pro- prius, zygomaticus, triangularis oris quadratus menti and risorius (see Fig. 43). These muscles are undergoing progressive metamorphosis corresponding to the development of man's cranium, intelli- gence and powers of speech, though they vary considerably in arrangement, number, and function. 1 Wiedersheim, loc. cit., p. 126. 9o THE HUMAN SPECIES \b FIG. 42. Muscles of the trunk and lower extremities. (Thome\) a, serratus max.; 6, m. intercost. ; c, m. abdom. transv. ; d, m. sartorius; e, m. rectus femoris ; g, m. quadratus femoris ; h, m. ossis pub. ; i, m. adduct. femor. long. ; k, m. semimembranosus ; /, adduct. longus ; m, semi-tendinosus ; n, tensor femoris; p, glutaeus ; q, r, ilio-tibial band; 5, biceps femor.; t, gas- trocnemius ; n, soleus ; v, Tendo Achillis ; it>, peroneus long. ; x, ext. long, digit.; y, extens. hallucis ; z, m. tibial. ant.; o, ext. brev. digit.; j8, abductor hallucis ; 8 tendo extens. digit, pedis. MUSCULAR SYSTEM D All anthropologists are agreed that man alone possesses the power of giving animated and varied expression to the mouth and eyes, and that he owes this power to the perfection of the above-mentioned muscles. Progressively modified are the muscles of the hand, particularly of the index finger and thumb. The extensor of the index finger, of which the anthropoids have but a mere suggestion (in the gorilla) ranks as the specifically human muscle, par excellence, on account of the power of gesticulation it bestows. The flexor proper of the thumb (m. flexor pollicis long, propr.) is also thoroughly de- veloped in man alone. In most human subjects the two flexors of the fingers (m. flex, dig. comm. subl. and m. flex, digit, comm. prof.) are sepa- rated in such a manner that the four tendons of the pro- fundus are inserted through slits in the four tendons of the sublimis. When this is not the case, the conditions are similar to those prevailing in many of the mammals ; for instance, in most of the apes (see Figs. 44 and 45). The great muscle of the lower extremity in man, the gluteus maximus, so superior to the corresponding muscle in the anthropoids, owes its massive formation and progressive development to its influence on the erect position. The gastrocnemius and soleus with their insertion into the calcaneum exhibit similar distinct human characters. In conclusion we may mention the flexor of the great toe (m. flex, hallucis long.) as another characteristic acquisition of progressive development (see Figs. 46, 47, 48). If we compare the gorilla, the highest of the anthropoids, with man we are immediately struck by the formation and FIG. 43. Facial muscles of mimicry. (Henle.) C, orbicularis palpebra- rum ; D, pyramidalis nasi ; E, levator labii sup. ; F, levator labii prop.; G, zygomaticus; I, zygo- maticus minor ; K, triangularis oris; M, risorius. THE HUMAN SPECIES development of the muscular system peculiar to the latter. In the face of the gorilla we miss the play of expression peculiar to the human countenance, and it consequently appears dull and lifeless. The thick muscular neck is clumsy and has but few joints. The pectoralis major is enormously developed as are also the muscles of the whole arm. In man, the upper arm, as well as the fore-arm, tapers finely towards the hand and the muscles of the fore-arm terminate in slender tendons, whereas in the M. abduct, poll, brev M. flex. poll, brev M. lumbricales M. abduct, dig. V M . opponens dig. V M. flex. dig. subl. Hiatus tendon, m. flex. subl. M. flex. dig. pro- fund. FIG. 44. Muscles of the human thumb and fifth ringer. (Heitzmann-Zuckerkandl.) gorilla the two parts of the arm are almost equal in size through- out their whole length. The nates, so well -developed in man, and the rounded finely tapering femur, present a strong contrast to the corresponding parts in the gorilla, where the nates are meagre and the adjoin- ing thigh bones are pressed inwards. In man the lower part of the leg becomes smaller from the rounded calf towards the ankle, whereas in the gorilla the con- ditions are exactly reversed, the leg being even somewhat MUSCULAR SYSTEM 93 larger at the ankle than at the knee, and the muscles are equally fleshy from origin to insertion. Aeby has tabulated the measurements of the tibial muscles, taking loo as the unit of measurement and arranging the dis- tinct groups of muscles accordingly. With regard to the Trapezius Deltoid m. ?- M . coracoidus H M. biceps / — M. triceps g Flex, digit, subli M. oppon. poll. .»_ Abductor Flexor brev.f- Adductor" Flexor indie. ) Sternocleido- J mastoideus M. pect. maj. M. brach. intern, t. M. pronator trans. , /_ M. supinator longus 'I ~ M. radial inter. M. radial ext. im. >- M. rerm. digit. Abductor dig. quinti. PIG. 45. Muscles of arm and hand, front aspect. (Thome, Zoologie.) a, m. palmaris brev. ; fj, serratus maj. ; y, m. abdom. obliq. ext. ; 8, fibrous sheath of rectus abdom. gastrocnemius muscle, man shows the highest figures with 57'2 per cent., as opposed to 35 per cent, for the chimpanzee and 27'8 per cent, for the orang ; in the pronator muscle of the foot both animals surpass man, but in the supinator, man comes first with IO'4 per cent, against 7^9 per cent, for the orang. With respect to the extensor and flexor muscles of the 94 THE HUMAN SPECIES toes, however, man is considerably inferior with 14-8 per cent, to 31-3 per cent, for the chimpanzee and 49-1 for the orang. a Trapezius / Deltoid m. f hi°tef.'lheadoftricePs i Tendon of triceps k Anconeus / Supinator longus p Extensor dig. comm. - n Extensor dig. quinti °, \ Extensor dig. comtn. r Abductor poll. long. s Extensor poll. t Ext. indicis prop. FIG. 46. Muscles of trunk, etc., back aspect. (Thome', Zoologie.) m, flexor carpi uln.; c, rhomboid; d, infra spinatus; b, m. latiss. dorsi ; e, m. abdom. obliq. ext. ; v, m. glut. med. ; n, m. glut. max. ; a/, m. semimemb. ; x, m. crur. ten.; y, m. semitendn. ; 2, m. biceps femoris; a, m. vastus externus; j3, gastrocnemius ; 7, m. popliteus. Man does not stand at the head of the animal world as INTEGUMENTARY SYSTEM 95 regards all parts of his organisation, but what he has lost on one side he has gained on the other, through the improved state of those organs which determine his place in nature as homo sapiens erectus. On the whole, as R. Hartmann (Menschenahnliche Afferi) has shown, the muscular system of the anthropoids, in spite of many apparently constant peculiarities, in spite of great mani- fold variation, does exhibit close resemblances to that of man, even in the face of the conflicting statements of different writers. Notwithstanding their incapacity for an erect gait and their • M. glutaeus med. M. glutaeus maximus Tractus iliotibialis fasc. latae M. tensor fasciae latae FIG. 47. Posterior muscles of the thigh. (Heitzmann-Zuckerkandl.) many animal characteristics, the chief feature of these muscles is still their great resemblance to human muscles, although, it need hardly be said, the experienced anatomist immediately distinguishes any anthropoid muscle from its corresponding human muscle.1 III. Integumentary System. The comparison of the skin of man with that of animals forms one of the most interesting chapters in comparative anatomy. A skin composed of three distinct layers (epidermis, 1 Ranke, loc. cit., i., 450. 96 THE HUMAN SPECIES basement membrane, and corium) (see Fig. 49), man shares with the other vertebrates, from the fishes to the mammals, but in spite of an extensive general correspondence, on histological examination the human skin presents, nevertheless, certain peculiarities in one direction or another, as well as finer dis- tinctions. To the ordinary observer the chief distinguishing feature of M. biceps femor. M. plantaris M. gastrocnemius M. peron. long. M. flex. hall. long. Lig. mall, lateralis M. peron. brevis Tendo Achillis M. semimembranosus M. semitendinosus M. sartorius M. gracilis M. plantaris M. flex, digit, longus M. tibialis posterior FIG. 48. Muscles of human calf. (Heitzmann-Zuckerkandl.) man as opposed to most of the mammals (with the exception of the whale, dolphin, dugong, hippopotamus and rhinoceros) is the comparative nakedness of his skin, only the beard, head, pubes and axilla being covered with hair. But this is not strictly true, for on a closer examination. of the surface of the body we find that it is everywhere covered with very fine hairs, even in the apparently smooth face of a girl, and these INTEGUMENTARY SYSTEM 97 hairs are naturally more noticeable the more the individual inclines towards the brunette type. This fact justifies our including man among the hairy animals, especially when considered in conjunction with certain phases of his embryonic development. In the seventh month of intra-uterine life, the human foetus is covered with a coat of fine, downy hair, which, on the authority of Eschricht, is arranged in crests and circles that determine its direction. The hair is then most thickly developed in the region of the ischial tuberosities, while the palms of the hands and the soles of the -r^" ~1 rr~ ___ -^-^~~.^-lL-^ • ~~ ^=^.rfte FIG. 49. Section of skin of finger tip. (Magnified twenty times). (Thome, Zool- ogie.) i, Epidermis; *, Lowest layer of same; 2, Basement membrane; 3, Papillae ; 4, Corium ; 5, Adipose membrane ; 6-6 Sweat ducts (pores of the skin) ; 7, Sweat glands ; 8, Section of a vein. feet, the red part of the lips and the glans penis and clitoridis are quite bare. This first coat of hair eventually disappears, and makes way for a new permanent one acquired during the first few years of life, the hairs of which gradually increase in size and become deeper in colour. Thus arises, besides the pale-coloured downy hairs, the darker hair of the head, eyebrows and eyelashes. On the approach of puberty the axillary hair and pubes are developed, these being peculiar to man and possessed by no other mammal,, and as full maturity is reached the growth of hair increases on the chest, back and extremities in the male 7 98 THE HUMAN SPECIES sex ; this latter peculiarity may be considered as a secondary sexual character like the long hair of the head in the female sex. Darwin x infers from the lanugo of the human foetus, and the rudimentary hairs scattered over the entire body during maturity, that the progenitors of man were completely covered with hair and that its gradual loss was probably due to sexual selection, the character of nudity being first acquired by the female sex and transmitted equally to both sexes ; Darwin concludes that man first became divested of hair in the ab- FIG. 50. Transverse sections of hair (magn.). (Waldeyer.) I. Hair of the head : a-c, of a brunette Jew ; d-k, of brunette and blonde Germans ; l-n, of a Negro ; o-q, of a Japanese. II. Hair of the beard: r-v, of brunette and blonde Germans; w-z, of a brunette Jew. dominal region, since the young chimpanzee is almost hairless on the under surface of the body. A variety of reasons might be assigned for the loss of the hairy covering, but to whatever cause it was actually due, the process must have taken place in a warm climate. Klaatsch suggests that it might also have been encouraged, or hindered, by food as well as by climatic conditions. Sexual selection may have played a part through the persistent eradication of the hair from certain parts of the body (in the face of the woman, 1 Darwin, loc. cit., vi., 354. INTEGUMENTARY SYSTEM 99 for instance) and inheritance of the tendency. Isolated cases are recorded where, by a curious persistence of embryonic con- ditions, certain parts of the body retain an abnormal covering of hair throughout life. Such are those human beings with tufts of hair in the inguinal region and the so-called hairy men or " poodle-men," whose faces are completely clothed with hair, resembling the faces of poodles (see Figs. 51 and 52). Formerly, no satisfactory explanation of this condition could be offered, and still less of the correlated abnormal con- dition of the teeth which resemble those of the edentata. But since the influence of the N. trigeminus on the development of the hair on the face and of the teeth has been made the sub- FIG. 51. Russian hairy man. FIG. 52. Julia Pastrana. (Ranke, Der Meiisch.) (Haeckel, Anthropol.) ject of special study, we are inclined to attribute such phenomena to a disturbance of the N. trigeminus during foetal development. It is a striking fact, however, that the strange condition is strongly inherited. Hence the explanation of atavism is in- voluntarily suggested to our minds, together with Darwin's conclusion that the ape-like ancestors of man must have been completely covered with hair, and that both sexes possessed a beard. The hair on the forearm is in man, as in the anthropoids and most of the mammals, directed upwards towards the elbow (Schwalbe). Man is distinguished from the anthropoids by the arrange- 7* ioo THE HUMAN SPECIES ment of the hair on the head. In man the hair is arranged circularly, radiating generally from one crown but sometimes from two, corresponding to the two parietal eminences. The hair on the scalp grows only as far as the beginning of the forehead which itself remains smooth and naked, whereas in the anthropoids the hair grows down to the superciliary ridges. A correspondence with human conditions is shown by the anthropoids in the fact that on reaching maturity a beard and whiskers are developed (see Fig. 53) ; the anthropoids, how- ever, rarely possess a moustache, only the Cercopithecus cephus having a moustache as well as whiskers. In most of the apes, FIG. 53. Pithecia satanas. (Brehm, Tierleben.) the distribution of hair in and about the face is the same in both sexes ; in some, as for instance, in the black howler monkey and certain species of macacus, the male has a somewhat better developed beard than the female. In no animal is the sexual difference in the hairiness of the body so marked as in man. Man's beard generally ranks as a secondary sexual character. From the fact that certain tribes (Hottentots, Nigritos, aborigines of America, Malays, Mongo- lians) are beardless, or at least have not yet attained to the possession of a beard, Alexander Brandt infers that the beard is to be considered as a progressive sexual character, but it is open to doubt whether perhaps exactly the opposite is not the INTEGUMENTARY SYSTEM 101 case, whether the sexual character has not been gradually lost in consequence of the hair having been persistently removed for ornamental purposes, in accordance with a certain standard of beauty. Among the aborigines of America, the custom of carefully eradicating every hair from the face is well known to be practised, and the same custom probably prevails among the other tribes quoted above, thus causing gradual atrophy of the hair papillae. Assuming Darwin to be correct in his view that both sexes of the anthropoid ancestors of man possessed a beard, it is to be inferred that the transmission of this character to the male sex alone, as is the case among the higher races, has been brought about by sexual selection, and that the absence of a beard in the above-mentioned lower races is to be regarded as a regressive phenomenon, though equally the result of sexual selection. It was formerly asserted that eyebrows were not present in any of the monkeys. It has been shown, however, by R. Hartmann that tufts of hairs are to be found in the apes in the region of the middle section of the arcus supraorbitalis similar to those in the other mammals (beasts of prey, ruminants, etc.). Yet another character possessed by man in common with the other mammals is the arrangement of the hair in groups of two, three, or five hairs together. In the foetus this is invariably the case,1 and Wiedersheim 2 has found that it is frequently retained to adult age, each single hair on the head being accom- panied by one to three fine short hairs, analogous to the group of hairs in an animal. Hence we find 3 that from each follicle spring several hairs, which are either similar or dissimilar as a complex follicle produces one thick hair together with a number of fine wool-like hairs, but there is no justification for the view that this arrangement of the hair on the head is exclusively characteristic of man. The so-called woolly hair of the negro in no way resembles the wool of the sheep. Sheep's wool consists of close tufts of fine, wavy hair ; the hair of the negro is also curly and arranged 1 Kolliker, Handbuch d. Gewebelehre d. Menschen, 1859, p. 120. 2 Wiedersheim, loc. cit., p. 8. :JC. Gegenbauer, Gnmdziige der vergl. Anat., 1873, p. 88. THE HUMAN SPECIES in tufts, but the tufts consist of coarse, matted hair, spirally curled. A further distinction between man and the animals is the absence of sinus hairs in man. In the lower animals these hairs occur in the neighbourhood of the nostrils, on the lips and throat, above the eyebrows and on the cheeks, and are dis- tinguished by having large, ant-egg-like follicles penetrating to the subcutis (see Fig. 54). Owing to the fact that the nature of the pith of the hair is invariably characteristic of a species, it is possible to distinguish between the hair of different animals and between that of animals and man. In a human hair the proportion of medullary substance to the whole hair is as 1:3-5 (see Fig. 50). The structure of the nails, both finger and toe nails, must not be ignored as it forms a distinctive character of man, especially as opposed to the apes. Among the semi-apes, which, it is true, stand nearer the rodents and insectivora, the thumb is furnished with a broad, flat nail, while the nail of the index finger forms a claw, resembling an awl in shape, and sometimes the other fingers are also provided with claws. The New World monkeys are similarly provided, the thumbs of all four hands being furnished with flat nails and the other fingers with sharp claws. With the exception of the gib- bon, which has a broad flat nail on the thumb and great toe, all the New World platyrrhines, as well as the Old World catarrhines, possess curved, claw- like nails on all the fingers without ex- ception. Careful observation shows us, however, that also in man the nail of the little finger at least is more arched than the rest. Various other structures exist in the human body closely resembling those of the lower animals ; : among others may be 1 Since the completion of the present work an interesting treatise has appeared : Zur Morphologic und Anatomic der Halsanhange beim Menschen und bei den Ungnlaten, by K. Frohner, Stuttgart, 1907. With 72 illustrations and n plates. FIG. 54. Sinus hairs of the Norway rat. (Thome, Zoologif.) INTEGUMENTARY SYSTEM 103 mentioned the "swimming membrane," that web or skin ex- tending between the fingers and linking them together. As we have seen above, in the hand of the gorilla the fingers are webbed as far as the middle of the first phalanx, and between the third and fourth fingers the skin extends almost to the second phalanx ; similarly in the chimpanzee all the fingers with the exception of the thumb are connected by a membrane extending to the joints between the first and second phalanx. Cases of excessive growth of this membrane in man are very rare. The normal web-like skin between the fingers can best be observed by viewing the back of the hand with extended fingers. Griming has measured the extent of the membrane between the fingers, and found, in the case of the index finger, the length of the free finger to be 6 mm. less than that of the entire finger, and the second finger at the second division 21 mm. ; in most cases the third finger proved to be on an average 4 mm.1 longer at the second division than at the third. The pigmentation of the skin cannot rank as a distinctive character of man in contrast to the lower animals, particularly to the mammals, for the same brown colouring matter, differing quantitatively, is found in the rete Malpighi, and in the uvea and posterior surface of the iris in all mammals, and among all the peoples of the earth. By far the greater number of human beings are brunette, or darker. Red-haired people and red- skinned, or copper-coloured, races have a special deposit of red pigment in the hair and in the rete Malpighi. The Albinos, human and animal, are the only instances of complete absence of pigment ; this peculiarity is frequently inherited. The members of the so-called white races possess in reality, under the epidermis, a supply of darker, or lighter brown pigment which appears, varying in intensity, in certain parts of the body (axillae, genitals, plica ani). Klaatsch assumes the colouring of the oldest races to have been intermediate between the present extremes, and proceeds to discuss the probable causes which may have led to the decrease of pigment in the white races, and thinks it to have been frequently brought about by the same agencies. The 1 Ranke, loc. cit., ii., p. 53. io4 THE HUMAN SPECIES influence of the sun cannot have been the sole cause of the differ- ence in colouring ; still less can we regard the paleness as due to a deficiency of light, for the aboriginal race of the Eskimos is dark, in spite of living for several consecutive months of the year in snow -huts. Klaatsch therefore suggests other factors : on the one hand, food ; on the other, the immunity against certain poisons and infections imparted to the body by a particular colouring of the skin. This character, acquired by natural and sexual selection, was first theoretically assumed, but later abundantly confirmed by observations made in the tropics. One of the most interesting discoveries of modern times is that of the blue Mongolian spots in European children. These spots are dark blue in colour and were first found imbedded in the corium of the inguinal region in Eskimo children of West Green- land, and later on in other Mongolian children ; B. Adachi and K. Fujisawa 1 have now found them to be present in European children also. Adachi has devoted special study to the pigment in man and gives his results as follows : — In Europeans the pigment of the epidermis is generally limited to the rete Malpighi and is deposited in and between ^____^_ the cells in the form of ?j«x-::.X;; ; Heart, large circulatory trunks 6 po werl Ul VOCal andlungs. (Thome, Zoologie.) a, vk ha rk Ik descending aorta; Ik, left ventricle; rk, right ventricle ; vk, right au- ricle ; ha, vena cava inf. ; 1, trachea ; e and f, two carotid arteries ; dand g, the two venas jug. int., c and i, the two subclavian arteries ; b and m, the two subclavian veins. organ than does man at the pre- sent day. Some observations in histol- ogy yield the following figures for the dimensions of human (see Fig. 65) and animal bronchioli and alveoli. The breadth of the bronchioli in man = O'i8 - O'22 mm. „ the horse = 0-22 - 0*58 „ „ cattle = o'275 „ „ the pig = O'OOS - 0*150 „ The average size of the alveoli in man = O'2 mm. „ the horse = O'i3 „ „ „ sheep = o-o6 - OT „ „ cattle =0*17 - O'2 „ „ the pig =0-15-0-2 „ „ dog = OT „ i 1 Wiedersheim, loc. cit., p. 195. ^M. Sussdorf in Ellenberger, Histologie, pp. 516, 518. THE HUMAN SPECIES The accessory glands connected with the respiratory system, namely, the thyroid and thymus glands, present no important points of difference in man and the mammals. Of the thyroid gland we know that it arises through segmentation of a part of the anterior wall of the primitive intestinal tube (Remak) in the form of a plexus of vesicles, which are lined with epithelium and sometimes appear in isolated groups, sometimes united in a single mass. In the lower mammals (monotremata, many marsupials and certain members of other classes) two distinct glands are found, one on either side of the larynx ; in other mammals, as in man, the two lateral masses are connected by means of a bridge. The diameter; of the follicles of the thyroid gland is:— = 0-045 - O'i mm. the horse = 0x350 - 0-4 „ cattle = 0x335 - o-2 „ the pig = 0-055 - 0-5 „ ! The origin of the thymus gland is obscure. In man and animals this organ is constructed of glandiform follicles and divided into large and small lobes ; in all vertebrates it is most fully de- veloped in youth and is, with rare exceptions, vestigial in the adult. In man it consists of two lobes unequal in size only in the em- bryo, and undergoes reduction and FIG. 65. Terminal ramifications disappearance, usually commenc- of the bronchial tubes with , r , , the air-cells. (Thome, Zool- mg towards the end of the second year of life. VI. Digestive System. In order to form a correct estimate of the distinctive characters of the human digestive system we must first examine what man possesses, in this respect, in common not only with the rest of the vertebrates but also with the invertebrates. 1M. Sussdorf in Ellenberger, loc. cit., p. 524. DIGESTIVE SYSTEM 119 The fundamental form is the cell with its protoplasm pos- sessing ingestive and egestive powers. The lowest of the pro- tozoa have no distinct organ for the reception and digestion of food. The food is either admitted endosmotically, in fluid form (gregarina), or enclosed in solid form by any part of the non-differentiated body and digested, the undigested matter being discharged at any point of the body (monera, amoeba, rhizopoda). The infusoria possess distinct organs for the reception of food in the form of tubular processes radiating from the sur- face of the body ; indeed a mouth and anus may be said to be present but without an intestinal tube. The porifera are furnished with a system of canals having mouthlike orifices not only for the admission and rejection of water, but also for the reception of food. The ccelenterata possess a digesting cavity in the middle of the body with a ciliated orifice opening outward ; this structure may be said to constitute a stomach surrounded by parenchyma. Combined with this primitive stomach in the majority of the ccelenterata, are canalicular or pouch-like formations, but an anal orifice opposite the mouth does not exist, the orifice of the mouth serving also for the discharge of undigested matter. Signs of considerable progress in the development of the digestive organ are seen in the worms, whose digestive ap- paratus is either imbedded in the parenchyma, or situated in the abdominal cavity. The structural improvement consists not only in the fact that, in most cases, in addition to the mouth at one end of the body, a dorsal or ventral anal orifice is present at the opposite extremity, but in the far more significant fact that three distinct intestinal segments are to be distinguished, namely, the small, the large, and the terminal intestine. Indeed, in the tunicata we find an oral cavity, in the form of the sac-like anterior part of the body, and a dis- tinct expansion of the large intestine. In the echinodermata, even in their larval state, a further development of the intestinal differentiation which commences in the worms may be recognised. The circumstance that the oral and anal orifices, originally situated diametrically opposite each other, eventually lie on the same surface is no essential 120 THE HUMAN SPECIES contradiction of the general plan on which the animal body is constructed, for it is exactly on this surface that the division of the two parts of the body is most clearly to be seen. The lowest members of the echinodermata are the asteroidea, in which the anal orifice is absent. The arthropoda show certain advances in structure, though, as regards the position of the digestive organ in relation to the other parts of the body, they correspond closely to the worms. An intestine is present passing throughout the whole extent of the abdominal cavity supported by connective tissue, and even by a few muscles. The anal orifice, which is invariably present, is situated either ventrally or terminally. As in the worms, the three distinct parts of the intestine may be clearly dis- tinguished. But the special distinction of this class is their apparatus for seizing and masticating food. This apparatus is placed at the entrance to the alimentary canal, and is formed partly by the borders of the oral aperture, in the form of projections (upper and lower lip), and partly by modifications of the articulated appendages of the body (pseudo-podia, mandi- bles), and is considerably in advance of the masticatory system of the asteroidea, crinoidea and echinoidea. In the crustaceans, whose intestinal canal follows a straight course, the terminal section of the small intestine is transformed into a masticating stomach by means of chitinous margins ; the large intestine is short with appendicular glands and caecal, saccular expansions ; the terminal intestine is quite short with but few csecal pouches. The narrow, small intestine of the arachnida leads into the large intestine, which is usually of relatively great length and provided with lateral caecal sacs ; the terminal intestine is ex- panded. The intestinal region of the myriapoda and insecta differs but little from that already described, except that in the latter the small intestine serves as masticating stomach, or crop, the large intestine is furnished with glands, and in the terminal intestine two distinct sections may be observed, the final one in the form of a rectum. The separation of the intestinal canal from the wall of the body, which commences in the worms and arthropoda, char- acterises the mollusca also ; equally clearly defined are the three portions of the intestinal canal, which is coiled in proportion DIGESTIVE SYSTEM 121 to its length, and the oral and anal apertures are diametrically situated, approaching each other only in the cephalopoda and pteropoda. The brachiopoda are organised on the simplest scale, having a mouth situated between the two arms, or arm-like processes. The lamellibranchiata have a short oesophagus attached to the mouth, hepatic ducts leading into the stomach and the terminal intestine coiled. Together with the develop- ment of a head in the gastropoda and cephalopoda, a pharynx with a deposit of chitine is formed, whereupon follow an oesophagus, a stomach, commonly divided into cardia and pylorus, a large intestine and a terminal intestine, generally expanded. To arrive at a clear understanding of the nature of the digestive system of the vertebrates we must trace their em- bryonic development. Here we find that the entoderm and an inner section of the mesoderm form the nucleus of devel- opment, that in the higher vertebrates the intestinal sac is primarily closed and only secondarily furnished with anterior and posterior apertures. After a further differentiation into an anterior and posterior section the latter, which passes through the visceral cavity, forms the intestinal tube proper. A further peculiarity common to all vertebrates, including man, is the fact that the anterior section of the primitive in- testinal tube acts primarily (as in the tunicata) as respiratory cavity, and that the alimentary canal originates in the fundus thereof. In spite of the broad breathing cavity of the acrania being reduced in the craniata, it persists, nevertheless, up to the highest vertebrates as a cavity serving both for respiration and for the reception of food. From the reptiles upwards the cavity is reduced by the insertion of the palate. The median elongation of the velum palatinum forming the uvula (see Fig. 66) is no distinctive character of man, since it is present in the apes and in the hare, and is found in a rudimentary state in the camel and giraffe. Except in size, the tonsils of the apes differ but little from those of man. The tonsils most closely resembling human ton- sils are those of the carnivora ; they are oblong and tuber- culated, consisting of follicular glands invested simply in a THE HUMAN SPECIES covering of mucous membrane. In the pig the glands are disposed superficially, side by side; in the ruminants and in the horse they form more or less circular masses, though here, too, there is no saccular disposition.1 Man possesses tonsils in common with the reptiles, birds and mammals. In man the tonsil is furnished on either side of the middle line with three or four deep longitudinal grooves and numerous nodules with a diameter of sometimes as much as I mm. A further peculiarity of the human mouth lies in the histology of its mucous membrane, neither a stra- tum granulosum, nor a stratum lucidum, being present, nor, with the ex- ception of the lips and a portion of the lingual epi- thelium, is any sign of cornification to be found. The fishes possess a rudimentary tongue in the form of a protuberance, invested in mucous mem- brane, above the hyoid bone, but a muscular, pro- trusible tongue proper we find first in the amphibians. In the reptiles and birds it undergoes further muscular development, though the apex is frequently horny, and only in the parrot is an entirely muscular tongue present. The tongue of mammals is essentially fleshy, with its (see Fig. 67) muscular structure, its covering of mucous mem- brane and the numerous differentiations of the same. In all mammals we distinguish the epithelium, the mucous membrane with its papillae (see below), the lamina propria of the mucous membrane, the glands, the muscular structure and the support- ing organs (hyoid bones). In addition, many of the cheiroptera, 1 Ellenbefger, loc. cit., part iii., pp. 101, 109. FIG. 66. Mouth, palate and pharynx. (Thome, Zoologie.) a, tongue ; bb', pala- tine arch ; cc', palat. pharyng. arch ; long o'3 »> broad 0-19 » thick.1 1 Ellenberger, loc. cit., p. 692. DIGESTIVE SYSTEM 129 Lieberkiihn's glands are completely absent in the fishes, but from the amphibians upwards are to be found in the large in- testine of all vertebrates. In man, as also in the mouse, rat, squirrel and bat, the fundus of the Lieberkiihn glands contains cells different from those which envelop the villi.1 In man, between every two villi occur from three to seven Lieberkuhn glands from O'2 to 0-3 mm. in length. Only in man and the mammals are Brunner's glands present. In man as in many of the mammals these glands are most numerous in the neighbour- hood of the pylorus. In the carnivora they cease immediately below the stomach : — In the horse . . 7 to 8 mm. "i , ,, ,r below the „ cattle . . i ., 6 „ >• ,, . stomach.2 „ the pig . . i „ 4 „ j The nodule or follicles which occur in the mucous membrane of the small intestine, either isolated, or in groups, are most abundant in the duodenum and ileum ; they are present also, though to a lesser extent, in the fishes and amphibians, undergo further development in the apes and birds, and attain their highest perfection in man and the mammals. The isolated follicles measure : — In man .... O'6 to 3 mm. „ the horse . . . 2 „ 4 „ „ cattle . . . 2 „ 4 „ In the sheep, goat, dog and cat the isolated follicles are considerably smaller.3 Peyer's patches have been studied in the domestic mammals as well as in man. In man they are from 80 to 100 mm. long and as much as 20 mm. broad ; in the horse they vary in size according to the number of nodules (50-200) ; in cattle and sheep 20 to 50 follicles are found, in the pig 24 to 30 small groups, in the dog 1 5 to 30, and in the cat 4 to 7 patches.4 The large intestine derives its name from its greater pro- portions as compared with the small intestine. This may be observed even in the short terminal intestine of the fishes, apart from the sphincter which in many of the fishes divides 1A.. Oppel, loc. cit., partii., p. 326. 2 Ellenberger, loc. cit., p. 695. 3 Ibid., p. 698. *Ibid., p. 698. 9 1 30 THE HUMAN SPECIES the large from the small intestine. In the amphibians and reptiles the large intestine is straight. In the birds and, still more markedly, in the mammals, and in man, it describes a longitudinal and transverse course, sometimes straight and sometimes coiled. The rectum alone corresponds to the terminal intestine of the lower vertebrates, while the remaining greater part (the colon), according to the latest research in comparative anatomy, is a comparatively new acquisition of mammals.1 Among the peculiarities of the terminal intestine the caecum demands special attention, as its occurrence and development are extraordinarily variable, and, where it occurs, its presence, and still more that of its vermiform appendix, imparts a special character to the colon. In most of the fishes, batrachians and reptiles, the caecum is absent, but in the reptiles traces thereof may be found. In birds its absence is rare ; where present it is frequently double. Of the mammals all pachyderms and ruminants possess a caecum as well as almost all the rodents, marsupials, sirenia, all apes, and man. In the carnivora it is either very greatly reduced, or entirely non-existent, but in the ruminants it is markedly developed. Still more rare is the occurrence of the vermiform appendix : indeed, it may be said to be absent in the majority of the mammals, but is found in certain classes of the rodents (wombat, mouse, rat), in the anthropoids, and in man. In man this rudimentary organ varies in length from 2 to 8i to 23 cm. ; among the anthropoids the length is : — In the gibbon . . . 8'5 cm. „ „ gorilla . . 24 „ „ „ chimpanzee . . 14 „ Although in the rat and mouse it is considerably smaller, corresponding to their bodily proportions, all anatomists agree that, as regards the whole formation of the caecum and appendix, the rat and mouse most closely resemble man. In the colon of man and certain of the domestic mammals, the longitudinal muscular tissue lies in three fasciculi (Taenias Valsalvae) ; in the pig there occur also three, in the horse first JA. Oppel, loc. cit., part ii., p. 591. DIGESTIVE SYSTEM 13 1 four and later three, but in the carnivora and cattle they are entirely absent. In man the glands cease at the upper end of the columnae rectales, and in place of the cylinder epithelium stratified pavement epithelium is found. As regards the isolated follicles, they are larger and more numerous in the large in- testine than in the small intestine. The entire length of the large intestine, in the adult, as compared with the small intestine is as I : 4. The two great glandular organs, the liver and the pancreas, stand in closest relation to the digestive system, as may be shown, ontogenetically and phylogenetically, from the in- vertebrates up to man. The peculiar, often coloured, cells or cell-groups, occurring in the intestinal epithelium of the worms may be considered as the primitive rudiments of a liver. Such gland formations are most highly developed in those worms where the intestinal tube ramifies (Planarians) ; here too may be mentioned the accessory glands peculiar to the intestine of the Tunicata. The coloured cells of the inner surface of the intestinal tube in the Echinodermata and, still more markedly, the caecal appendix of the intestinal tube in the star-fish secrete a bile-like fluid, though neither can be said to possess a true liver in the sense of the liver of the higher animals. The glands connected with the large intestine of the arthropoda are admitted by all anatomists to be hepatic glands. The gradual development of the liver may be traced in the different classes of the mollusca. In the Brachiopoda and Pteropoda, consisting still of a number of tubes, the liver ap- pears in the Lamellibranchiata as an organ constructed of acini and lobes surrounding the stomach and a great part of the intestine. The liver of the Gastropoda is equally im- portant, and in the Cephalopoda, in the form of a compact gland with excretory ducts from the separate lobes, it has already assumed the character of the liver of the vertebrates. As in the invertebrates, the liver appears in its most primitive form as a tube-like appendage of the intestine, so also in the vertebrates, its development from the wall of the rudimentary intestine may be traced in the embryo. In its simplest form (as in the Amphioxus) it is a caecal appendix of the first 9* 132 THE HUMAN SPECIES portion of the intestinal tube, invested in epithelium of a greenish colour. In the embryo of other vertebrates (reptiles, birds, mammals and man) it consists of a double expansion of the intestinal tube where the latter forms the stomach ; two hepatic lobes gradually develop and later combine into one organ. Although, on the whole, the human liver closely corre- sponds to that of the anthropoids, there still exist certain fine distinctions, to which Ranke J has drawn attention in his frequently quoted work. For instance, he regards it as worthy of mention that the H -shaped arrangement of the sulci on the FIG. 72. Inferior surface of the liver. (Ranke, Der Mensch.) a, right hepatic lobe; b, left hepatic lobe; c, gall-bladder; d, vena cava ; e, Spigelian lobe; f, quadrate lobe ; g, porta hepatis ; h, hepatic duct ; i, cystic duct ; k, common duct; 1, lig. teres. posterior surface (see Fig. 72) is absent in the gorilla (Bischoff), chimpanzee and oran-utan (R. Hartmann). The liver of the gorilla differs further from that of man in that, in addition to the two principal lobes, it sometimes possesses other lobes indenting the margins. In conclusion it may be observed that the gall-bladder of the chimpanzee is -larger than the same organ in the other an- thropoids and in man. The close resemblance of the human liver to that of the pig has frequently been emphasised, but 1 Ranke, he. cit., i., p. 293. DIGESTIVE SYSTEM 133 microscopic research reveals fine distinctions which are not to be ignored. Thus, the hepatic lobes are: — In man . . ri to 23 mm. long '8 „ i'5 ,, broad In the pig . . 1-5 „ 2-5 „ long i „ 1-5 „ broad 1 Oppel - also mentions the similarity between the human liver and that of the pig, but draws attention also to its resemblance to that of the dog. He regards as the distinctive characters of the human liver (see Fig. 72) the frequent union of the lobes to double and three-fold formations ; further, the circumstance that the FIG. 73. A portion of the liver. (Thome, Zoologie.) i, artery; 2, portal vein ; 3, bile duct. FIG. 74. Liver cells. (Haeckel, An- thropogenic.) majority of the intralobular biliary ducts are situated in the marginal surface of the hepatic cells, though, between the mar- gins, biliary ducts also occur on which border three or four hepatic cells. The average diameter of the human hepatic cell (see Fig. 74), which frequently shows two distinct nuclei, is from 18 to 26 m., the lobes measuring i mm. crosswise and i'5 to 2 mm. lengthwise. The first appearance of a pancreas among the invertebrates is in the molluscs (Gastropoda and Cephalopoda), either in the form of gland lobules attached to the excretory ducts of the hepatic lobes, or in that of a pouch provided with a folded 1 Ellenberger, loc. cit., p. 710. 2 A. Oppel, loc. cit., part iii., p. 1067. 134 THE HUMAN SPECIES wall (Aplysia, Doris) and discharging itself into the stomach.1 In all the vertebrates the pancreas originates in an expansion of the intestinal wall, occurring behind the rudimentary liver. In man also there first exist two rudiments, a dorsal and a ventral. In the domestic mammals the dorsal rudiment becomes eventually the duct of Santorini, the ventral the duct of Wirsung ; in man, with rare exceptions, the latter duct alone persists. In man, as also in the fishes, birds and mammals, small aciniform glands, assumed to be mucous glands, are found in the wall of the Wirsung's duct. VII. Urogenital System. In the foregoing chapters we have seen that, in spite of man's position at the summit of the organic scale, he stands, nevertheless, in close connection with the more lowly organisms, being able to present few specific peculiarities in his structure. His urogenital system is no exception in this respect. Here, as before, we must go back to the lower forms of the animal organism in order to fully understand how the human organs have acquired the form we know them to possess. In the very lowest organisms, the Protozoa, with their extreme simplicity of structure, an organ of excretion is hardly to be expected ; in the Ccelenterata the excretory functions are performed by the general gastro-vesicular apparatus, and only a few possess organs which may be regarded as rudimentary kidneys. Such are the Actinia possessing mesenteric filaments, which have been ascertained to contain guanin, and, among the Siphono- phora, the Porpita with their curious spongy organ situated beneath the discoid air cavity. It is clear that in the lower marine animals, whose organism freely communicates with the surrounding water, an excretory organ of the nature of a kidney could not be developed to any great extent. Among the Echinodermata there are only a few types in which special organs of excretion are found ; such, apparently, are the interradial tubes with glandular walls as possessed by the Asteroidea, with and without an anal orifice, 1 C. Gegenbauer, Vergl. Anat., p. 533. UROGENITAL SYSTEM T35 and the variously formed canals which penetrate into the cloaca of certain classes of the Holothurians.1 There is sufficient ground for the assumption that these act as primitive excretory organs, even though the nature of the excreta be not as yet fully ascertained. The higher we rise in the organic scale the greater is the importance assumed by these organs and the more clearly are the excreta to be recognised. In the worms these latter take the form of granules and concrements corre- sponding chemically to the matter excreted by the kidneys of the higher animals and of man.2 " According as the body is articulate or inarticulate the excretory apparatus is complex or simple." Where the body-cavity is not clearly defined the ends of the tubes as well as the finest ramifications of the canals are closed, otherwise the canals, simple or ramifying, open on to the surface of the body, and, where the body-cavity is very clearly defined, into the interior also, when a special ciliated organ is seen ; indeed, in the Trematoda and the Radiata a common contractile bladder is found. The Nematoda exhibit a pore in the linea alba through which the contents of the two united lateral canals are excreted ; the Annelida have two canals regularly divided and almost invariably provided with an internal, ciliated orifice and an external orifice at the opposite extremity of the body ; the Gephyrea, lastly, possess two separate organs of excretion, the walls of the canals being of a glandular character ; one organ acts as a kidney, the other as a reproductive organ. Thus early do we find indications of the urogenital system of the higher animals. Among the Arthropoda little is definitely known as to the urinary organs of the Crustaceans. It has been ascertained that the larvae of the Copepoda possess a temporary excretory organ in connection with the extremity of the large intestine, and the excretory nature of the so-called testaceous glands in the double shell of the Daphnia, in the head-shield of the Apus and in the shell-valves of the Limnadiacea cannot be doubted, but it is still uncertain whether the looped canals of certain Crustaceans are true organs of excretion or not. On the other hand, the so-called Malpighian vessels, occurring in JC. Gegenbauer, Vergl. Anat., p. 342. zlbid., p. 253. 136 THE HUMAN SPECIES other members of the Arthropoda (Arachnida, Myriapoda and Insecta) and formerly thought to be bile ducts are now ascertained to be urinary organs, for they undoubtedly excrete uric acid, as is seen, for instance, in considerable quantity, in the red or yellowish moisture of the Lepidoptera, on their leaving the chrysalis. Typical organs of excretion are the looped canals of the molluscs ; they commence externally and after a course of varied length open into the body-cavity; the chemical com- position of their excreta confirms the view that they act as kidneys. In the Brachiopoda and Otocardia the kidneys are repre- sented by one or two pairs of canals ; in the Pteropoda and Heteropoda a kidney of a spongy nature is found, while of still more markedly spongiform construction are the renal bodies which occupy the two final, branchial branches of the vena cava'as far as the branchial heart.1 Proceeding from the Invertebrates to the Vertebrates we find the organs of excretion bearing an increasingly close re- semblance to those of man. In the Myxinoidea, belonging to the Cyclostoma, the simplest of conditions still prevail, it is true, but in the Bdellostomata the caecal transverse canaliculi of the ureter enclose a vascular convoluted body, or glomerulus, and the kidneys of the Petromyzontidae - are still more highly convo- luted, though as regards their uriniferous tubules they are very similar to the above. Peculiar to all members of the verte- brate kingdom is the early development of an excretory organ which, however, retains its original function of excretion only in the lower vertebrates, being superseded in the higher by a new organ, whereby the first either remains with a new func- tion, or disappears from the organism. In the fishes the two symmetrical, bilateral, lobular Wolffian bodies of glandular character situated at the lower part of the vertebral column originate from the posterior parts of the primordial renal ducts on either side of the vertebral column. The Wolffian bodies combine to form a single duct which opens either into a cloaca or separately behind the anal aperture. Thus an expansion in the form of a urinary 1 C. Gegenbauer, Vergl. Anat., p. 355. 2Ibid., p. 861. UROGENITAL SYSTEM bladder can be formed either in each separate ureter, or at their point of union, or at a still lower point. The Amphibians retain only the posterior part of the Wolffian bodies in a perfect state, either as a coherent mass or in the form of con- secutive segments. Moreover, a secondary duct in addition to the primary Wolffian duct either remains on either side of the Wolffian bodies, at that point where it communicates with the Wolffian duct, or arises through the union of the transverse excretory ducts. In the Amniota the Wolffian bodies are permanent, but in the Amnia they do not persist beyond the embryonic period (see Fig. 75). The permanent kidneys arise from the Wolffian ducts in the form of a bud, near the opening into the cloaca. In the reptiles the kidneys are placed far back and generally in the neighbour- hood of the cloaca, and possess a consider- able number of longitudinal convolutions, or lobes. The lizards and tortoises, like the amphibians, have a bladder springing from the wall of the cloaca. In birds the kidneys are embedded in the cavity between the transverse processes of the coccygeal vertebrae and consist usually of three lobes, sometimes united ; the ureters, which generally originate at the inner margin, open separately into the cloaca. The development of the mam- malian kidneys does not differ from that of the reptiles and birds.1 At first the kidney is unilobular ; later it is divided into lobes through separation of the glandular parenchyma, whereby the tubuli uriniferi in each lobe (see Fig. 76) combine to form a papilla, and the renal calyces unite to form the pelvis of the kidney (see Fig. 76). The number of lobes varies considerably but can always be ascertained from the number of the different papillae, simple and compound. The seals, bear and otter possess a small number of dis- 1 C. Gegenbauer, Vergl. Anat., p. 867. FIG. 75. Wolffian bodies of the human em- bryo. (Kobelt.) u, Tubuli urinif. ; m, Miillerian duct ; w, Wolffian duct. 138 THE HUMAN SPECIES tinct lobes. When the lobes are partly united the surface of the kidney becomes tuberculated, as in hyaena, ox and ele- phant ; when the cortical substance of the lobes is completely fused the surface of the kidney is quite smooth. If the lobes coalesce to such an extent that the majority thereof or the en- tire number are affected the result is a much smaller number of papillae, indeed there is sometimes but one single papilla present, as in the Marsupials, Edentata, Rodentia and certain of the Car- nivora, e.g., the dog and the cat. FIG. 76. Section of human kidney FIG. 77. (i) Malpighian body of man. (Ranke). a, renal papillae ; b, apex; A, B, C, Tubuli uriniferi ; magnified c, middle part ; d, cortical layer ; e, 300. (2) 3 epithelial cells from pelvis renalis ; f, ureter. convoluted canaliculi ; magnified 350. (Kolliker, Gewebelehre.) A peculiarity shared by man with all the mammals is that at first the ureters are embedded in the urachus section of the allantois, from which the urinary bladder is gradually developed, the process of the urachus towards the umbilicus and umbilical cord becoming ultimately obliterated. The consequence is that the bladder originally projecting far into the abdominal cavity gradually retreats to' the pelvis. The size of the urinary bladder, as well as its general structure, varies in the different mammals. In the Bovidae it is highly convoluted, in the Carnivora smaller, more muscular and almost circular. UROGENITAL SYSTEM 139 The human urinary bladder occupies an intermediate place and measures, according to its contents, 50 to 100 mm. in height, 40 to 80 mm. in breadth, and is capable of containing 200 to 400 cubic cm. The lobes of the human kidney being united into a single whole, as is the case in most of the mammals, the human organ has the same bean-like form and smooth surface as that of the mammals, and only in rare cases is its construc- tion of separate lobes revealed by an uneven surface. The human kidney, however, on being compared with the kidney of the mammals presents certain structural peculiarities, as, for instance, the number of papillae. These, in man, are to the Malpighian Pyramids always as 10 : 15, whereas the oran-utan, rabbit, dog, cat, cavy, hyrax, lutia, Rhyzaena and gryson possess but one papilla, and some rodents, Mus, for instance, have two, while the elephant has three, the hedgehog five, and the pig • nine to eleven. Tereg l gives the following diameters for the glomeruli of man and of various domestic mammals : — Man ..... O'2 mm. Horse . . . . 0*187 ., Cattle .... 0'22i „ Sheep .... O'2io „ Goat . . . . O'iSo ,. Pig 0-175 „ Dog 0-136-170 „ Cat O'i22 „ As regards the convoluted tubules the difference is less important. Their diameters are as follows : — In man ..... O'O5 mm. „ the horse .... 0^05 1 „ „ cattle 0-05 „ the sheep . . . o-o6 „ „ „ goat . . 0-051 „ ,, pig • 0-05 „ „ dog 0-048 „ The kidney of the Oran-utan has neither lobules nor Co- lumnae Bertini ; further, no renal calyces are present, and only 1 In Ellenberger, Vcrgl. Histol., p. 264. 140 THE HUMAN SPECIES one single papilla, very broad and smooth, discharges the urine into the pelvis. Whether similar conditions obtain in the other anthropoids has not been ascertained up to the present. Reproductive System. In a comparison of the reproductive organs of man and the animals it would be a mistake to ignore the non-sexual mode of reproduction which prevails among many animals, from the Protozoa to the Annelida and Arthropoda, for the same pro- cess of segmentation in the cell, which precedes the asexual budding, or gemmiparity, takes place also in the gradual matur- ing of the human ova and spermatic cells. Of far greater significance certainly are the points of contact between man and the animals when we come to sexual reproduction, or reproduction based on differentiation of the sexes, which, commencing in the Infusoria and Sponges, continues throughout all classes of animals up to man. In the Sponges, ova and spermatic cells are produced from the parenchymal cells without the mediation of special re- productive organs ; in the Infusoria, the nucleus acts as the female, the nucleolus as the male element, which combine after the conjugation of two individuals. In the Ccelenterata, which are either bisexual or of distinct sexes, special organs for the production of generative matter appear only at fixed periods ; when the germinal glands are situated on the surface the generative substance immediately reaches the exterior, but is discharged through the gastro- vascular system when the glands are more deeply situated. In the Echinodermata, with the exception of the Synapta, the sexes are distinct, and the reproductive organs are radially arranged. In the absence of sexual organs, the ova are fertilised in the water by the round-headed spermatozoa. Of considerably higher organisation are the worms : the hermaphrodite Bryozoa, Turbellaria, Trematoda, Cestoda, Hirudinea and Tunicata. The testicles, varying in number, and the ovary, together'with its vitelline cavity, are generally united at a common opening ; there is also a vas deferens, a kind of vesicula seminalis, and sometimes at the common excretory duct of the ovary and vitelline cavity an expansion appears UROGENITAL SYSTEM 14 ! which may be regarded as a uterus. Preliminary to the separa- tion of the sexes an unequal development of the double sexual apparatus in one and the same individual takes place, being on the one hand unduly increased, on the other arrested. The Nematoda, Chaetopoda and Radiata, in all of which the sexes are separate, possess tubular testes and ovaries ; the Nema- toda having seminal vesicles, oviducts and uterus. The sper- matozoa of the Annelida are clearly motile and have frequently a condensed head part. In the Arthropoda, in spite of their variability, progress from a lower to a form more closely re- sembling the vertebrates is to be traced, one of the most important signs thereof being the increased tendency to separa- tion of the sexes, hermaphroditism occurring only among the lower types. Where the sexes are distinct, the reproductive organs are either single (of the Crustaceans, the Copepoda and certain of the Arachnida), or paired and bilateral-symmetrical (Branchiopoda, Arthostraca and, of the Arachnida, the Galeodes and Araneida, besides all the Insecta). The Insecta are more highly organised, in that they possess a vesicula seminalis in the male sex, and a receptaculum seminis in the female sex. The Brachiopoda, parts of the Lamellibranchiata, and a large proportion of the Cephalophora are hermaphrodite ; in the remaining Cephalophora, and all the Cephalopoda, the sexes are separate. To the latter belongs the peculiarity of having the spermatozoa enclosed in a spermatophore. We have seen that in the Invertebrates the germinal glands are at first undifferentiated, and that, even after this character has disappeared, hermaphroditism is still very widely spread. Now it is one of the most eminently distinctive characters of the Vertebrates that the germinal glands are strictly differentiated into organs for the formation, respectively, of ova and semen, and the sexes are represented by separate individuals, although, as far as has been ascertained, both the germinal glands originate in the same embryonic rudiment, the Wolffian duct. Another character common to all the Vertebrates is the development of ovarian follicles from groups of cells in the primitive ovarian tube. Common to man and the mammals is the peculiar con- struction of the ovarian follicle — the ovum being contained within a Graafian follicle filled with fluid — and the minuteness r42 THE HUMAN SPECIES of the ovum, wherein, however, the nucleus ovi (blastodermic vesicle) and the nucleolus (germinal spot) may be distinguished. The diameter of the Graafian follicle is : — In man ...... 10-12 mm. „ other mammals as much as i cm. and more. The mature human ovum measures OT-O'3 mm. animal „ „ 1-1-5 » These figures show that the human ovum is easily distinguish- able from animal ova. A general survey of the entire vertebrate kingdom, including the most highly developed mammals and man, reveals extremely primitive conditions as regards the sexual organs of the lower forms of life. Thus in the Cyclostoma the testicles unite and form a simple organ which, in the absence of excretory ducts, discharges its contents when mature into the abdominal cavity, whence the semen is eventually evacuated. The Selache, Chim- aera and Dipnoi have paired but small testicles with epididymis and on either side a vas deferens, and paired, symmetrical ovaries which, however, are not connected with the oviducts in spite of these being also paired. From the fact that each ovi- duct becomes dilated at its lower extremity there results, on the right as on the left, a kind of uterus, each of which opens into the cloaca. The Ganoidei appear extremely backward in their development, being so simply organised that the ovaries as well as the testicles discharge their products immediately into the abdominal cavity, without the aid of special excretory ducts, and thence through a short canal into the ureter ; in certain species the ureter can open into the above-mentioned canal (Mullerian duct). The highest fishes are the Teleostei with their usually elongated testicles and ovaries, the latter in many species even serving as brood cavity for the development of the embryo. The amphibians in many respects resemble the fishes, the convoluted oviducts being situated beside the paired ovaries and, after uniting with the permanent and active Wolffian ducts, open into the cloaca. On the other hand, the testicles are united with the Wolfifian bodies, one part secreting the semen and another part performing the function of kidney. The Wolffian bodies do not persist in the Vertebrates higher than the reptiles. The male sexual organs consist of testicles UROGENITAL SYSTEM 143 generally oval in form, lying close to the vertebral column, and the epididymis with the vasa efferentia and vasa deferentia opening into the cloaca. The ovaries are aciniform ; the ovi- ducts (appearing as Miillerian ducts developed from the original Wolffian ducts) form as a rule important passages, each furnished with an abdominal infundibulum and a short excretory duct opening into the cloaca. The conditions prevailing among the birds are very similar, with the peculiarity that (with the exception of a few birds of prey) both the ovary and oviduct on the right side are un- developed. This peculiarity occurs also in the Monotremata. Each of the two Miillerian ducts forms a canal (oviduct), which opens into a sinus urogenitalis communicating with the cloaca and forms a uterus at its lower end. In the Marsupials the two Miillerian ducts are so connected that on each side a uterus, oviduct and vagina are formed, or the lumina unite into one cavity, whence they again separate to reach the sinus urogenitalis. The Monotremata and Marsupials are mammalia aplacentalia. In the Placentalia, to which homo sapiens also belongs, the embryo communicates with the vascular system of the mother through the placenta and remains enclosed in the uterus until fully developed. The germinal glands transformed into testicles are situated at first, like the ovaries, at the inner margin of the Wolffian bodies. When the Wolffian body unites with the testicle the former develops into the epididymis, the Wolf- fian ducts into the vasa deferentia and the Mullerian ducts remain rudimentary. Thus, only in the Monotremata do the testicles retain their original position ; in the Cetaceans, Hyrax, elephant and certain of the Edentata the testicles are placed below the kidneys ; in many rodents, the camel and certain of the Carnivora, they occur in the inguinal region of the abdominal wall ; lastly, in many of the mammals and in man they are contained in a scrotum. Other conditions obtain among the female members of the mammalia placentalia. The Wolffian ducts do not develop, while the Mullerian ducts form the oviducts, the uterus and vagina. Signs of an earlier structure are seen in the bicornuate i44 THE HUMAN SPECIES uterus opening into a single vagina, as found in many of the rodents, and in the partially divided uteri of other mammals, occurring also not infrequently in the human subject. With regard to the copulative organs, animals as low down in the scale as the worms possess a penis, to which corresponds in the female a vagina with bursa copulatrix for the admis- sion of the penis. In the Crustaceans (Arthropoda) a canal in the sexual organ (in the form of a foot) serves as penis for the introduction of semen ; in the Insecta the male is furnished with a copulative organ, varying in form, which is introduced into the bursa copulatrix of the female. Of the Mollusca only the Gastropoda and Cephalopoda possess a male copulative organ ; among the latter one of the arms undergoes a curious metamorphosis in order to serve as such. We find a similar transformation of an organ in the fishes (Selache and Chimaera) where a part of the ventral fin acts as spermatic duct and sexual organ. Other of the Selache have a protrusile organ, sometimes cartilaginous, similar to that of the Crustaceans, to which corresponds in the female roach a smaller organ resem- bling a clitoris. Surbeck considers the sexual organ of the Cottus gobio, a sub-species of the Teleostes, to possess the character of a penis, but Hyrtl points out that in the absence of corpora cavernosa this structure in the Teleostes cannot be regarded as a penis. Of the amphibians the salamanders possess a papilla open- ing into the cloaca, while the reptiles have sexual organs either proceeding from the wall of the cloaca in the form of tubes, or constructed of fibrous tissue. In the saurians and snakes the protrusile tubes, furnished with a spiral, seminal sinus, are dilated in the middle and bifurcated at the extremity, the glans penis being provided with spinous epithelium, which, however, is absent in the homologous female gland, the clitoris. Both here, and in the tortoise and crocodile, the higher vertebrate form of corpora cavernosa cannot be said to be present. The copulatory organ of the birds bears a close resemblance to that of the reptiles, being usually in the form of a tube sup- ported by fibrous tissue ; the didactylous ostrich possesses a penis consisting of two bodies united together and enclosed with a UROGENITAL SYSTEM 145 mucous membrane. The male organ of reproduction in all mammals up to man possesses similar fibrous corpora caver- nosa abundantly supplied with veins. Moreover, these corpora cavernosa (except in the case of the Marsupials, which differ also through their double penis) are connected with those of the urethra, which in all the higher mammals has been caused by the development of the sinus urogenitalis into a long narrow canal, and with its corpora cavernosa and the glans penis has been most instrumental in the formation of the true penis, whereas the homologous female organ, the clitoris, also provided with corpora cavernosa, is not united with the urethra (except in the Lemur and some of the Lemuridae), nor has it any connection with the urinary discharge. In the bats, carnivora, seals, whales, many rodents and apes, the penis contains inter- nally a supporting bone, but whether this is the case in the anthropoid apes I have been unable to ascertain. In most of the rodents the penis is either entirely or parti- ally surrounded by the sphincter ani ; in most of the other mammals it is attached, varying in extent, to the median linea alba, and only in the bats, the apes and man depends from the pubic arch. This cannot, therefore, be reckoned among the distinctive characters of man, but it has been ascertained that the hymen, in its characteristic form, is possessed ex- clusively by the female human subject, the horse, ruminants, carnivora and apes having only what may be called vaginal valves. In addition to the organs of excretion and reproduction, the accessory gland organs present many points of similarity and difference. Diisselhorst1 has made these interesting organs the subject of exhaustive study, and to his work I shall refer as being the most reliable source of information. The Littre urethral glands are present not only in man, in the upper wall of the pars prostatica and in the pars cavernosa of the urethra, but also in the mole and Cheiroptera (Insectivora), in the Leporidae, Muridae and Cavia (Rodentia) and in the Bradypus tridactylus, all Marsupials and Monotremata (Edentata). The Cowperian glands are very widely spread throughout the king- dom of the mammals. In man these aciniform glands are 1 A. Oppel, loc. cit., vol. iv., 1904. IO 146 THE HUMAN SPECIES about the size of a pea (5-9 mm. in diameter), having an excretory duct with a diameter of O'5 mm. The Bartholini glands of the female corresponding to the glands of the male are absent in the female ape, being replaced by numerous cavities, which, in their turn, are absent in the human female. On the other hand, the Cowperian glands are larger in the apes than in man, though, compared with the corresponding glands in most of the other mammals, they appear smaller. Among the Carnivora they are found well developed in Felis and Herpestes ; among the Insectivora, in the hedgehog and mole ; all Cheiroptera ; in the ruminant and non-ruminant Ungulata, and in many of the rodents. In the Equidae where the glands are well developed they have from six to eight ducts opening into the urethra. In the Edentata but little is as yet known of them, as they have been found only in the Myrmecophaga tridactyla, Chlamydophorus truncatus and Dasypodida, but in the Marsupials and Monotremata they are undoubtedly present and are confined to the male sex. The Prostate is not a specifically human organ ; indeed, it occurs in almost all classes of the mammals. The only point characteristic of man is that this tubular aciniform gland con- tains strands of muscular fibres. The separate acini have a diameter of 0*21 to 0*30 mm. In the apes the prostate is always well developed, bearing no trace of having originally consisted of two halves ; only in the orang, where it is longer and narrower than in man, is it divided into two lobes by a longitudinal sulcus. The bilobular construction is also peculiar to the Cheiroptera. Among the Insectivora the gland is clearly of double construc- tion, as shown in the mole and hedgehog ; in the non-ruminant Ungulata it sometimes appears fourfold, and in the Proboscidea consists of even more lobes, while in the sub-ungulata, Cetaceans, ruminant Tylopoda (with the exception of the giraffe) and Bovidia, as well as in the majority of the rodents, the prostate forms a solid independent mass. The form varies greatly in the Carnivora, the prostate of the Canidae, enclosing by means of its spiral form the whole of the urethra, presenting a sharp contrast to that of the Felidae and Herpestes where the dorsal half of the gland is entirely absent. In the majority of the UROGENITAL SYSTEM 147 ruminants, with the exception of those mentioned above, the prostate is replaced by a glandular layer between the urethral mucous membrane and the urethral muscle ; similarly in the Marsupials and Monotremata a stratum of urethral glands occupying the urethral wall supplies the place of a -prostate. One of the most remarkable structures in the province of the urogenital system of the male human subject is the vesicula prostatica, known to Morgagni and Albin, the small membranous vesicle situated in the prostate and discharging at the colliculus seminalis between the ejaculatory ducts ; according to Weber the history of evolution proves the vesicula prostatica to be a uterus masculinus. Riidinger has compared the vesicular fundus with the uterus and the lower section with the cervix and vagina, and is of opinion that the organ is not of so rudi- mentary and unimportant a nature as is generally assumed. In man the ejaculatory ducts only in rare cases open into the vesicula prostatica, but in the rodents where the vesicula seminalis is absent this is the rule. Little study, apparently, has been made of this organ in the other mammals, and with regard to its presence in the anthropoids no information has come to my notice. If, however, the theory of Reliquet and Guepin were to be confirmed, that only the human vesicula prostatica possesses follicles analogous to the alveolar depres- sions of the spermatic duct and the ejaculatory duct, this would indeed constitute a new specific human character. Glands in communication with the wall of the spermatic duct (ductus deferens) occur not only in man but in several of the classes of mammals and amphibians. In man these glands take the form of large cavities distributed over the wall of the spermatic duct, filled with secretion and furnished with excretory ducts. These glands form a distinctive character of man as contrasted with the rest of the Primates, they being absent in the latter. The glands of the spermatic duct constitute a distinction between the otherwise nearly related Insectivora and Cheiroptera, in that they are absent in the former and well developed in the latter. In the ruminants they occur in varying form and are absent only in certain of the Tylopoda. The possession of spermatic duct glands, with or without ampullaceous dilation of the duct, belongs to the peculiarities 10* 148 THE HUMAN SPECIES of the Subungulata and many rodents (rabbit, beaver, true Muridae and hamsters). In birds and reptiles no spermatic duct glands are formed, but they abound in the amphibians. In the male Anura either the caudal or oral extremity of the urethro- spermatic duct expands ; during the spawning season it forms a sinus of considerable size, but disappears during the winter. In the Urodeles there is no sign of this ampulla in the spermatic duct. The reproductive organs of the Vertebrates possess also other special glandular vesicles serving as receptacles of semen and hence called seminal vesicles. These vesicles attain full development in the embryo of six months, and their occurrence is not peculiar to man but common to the apes, lemurs (with the exception of Cheiromys), Insectivora, ruminant and non- ruminant Ungulata, Subungulata, rodents and Edentata. In the birds the dilation of the posterior wall of the spermatic duct before the opening into the cloaca is not of glandular construc- tion but acts merely as a seminal reservoir. Of the same nature is the olive-shaped expansion of the lower end of the ureter, which receives the ductus deferens, in the snakes. With regard to fishes, the Selache have no seminal vesicles, properly speaking, but in a number of Teleosteis (gobies, blennies, Cobitis, pike, etc.) Hyrtl has discovered seminal vesicles in connection with the testicles. In conclusion, the odoriferous glands of the anal and cloacal regions deserve consideration. It would seem at first sight that anal glands are absent in man unless we regard as such those sebaceous glands embedded in the hairy perinaeum which emit a secretion with a strong odour. True anal glands are absent in the apes, lemurs, ruminant and non-ruminant Ungulata, Subungulata, Proboscideae, Cetaceans, Sirenia and Edentata, while in the remaining classes of mammals they are sometimes very well developed, especially in the Carnivora, where they occur in both sexes. Further, certain of the rodents (Leporinae) possess special inguinal glands varying in colour and emitting a secretion which probably, like that of the anal glands, is connected with the reproductive system. Of the reptiles, the lizards in both sexes have small sebaceous glands situated ventrally from the cloaca, the tortoises simple non-glandular NERVOUS SYSTEM 149 anal vesicles, and the crocodiles rather large glands, called musk glands, opening into the cloaca near the anus. In the opinion of Diisselhorst the cloacal glands of the male Urodeles may be compared to the prostate, but up to the present nothing has been recorded as to the abdominal and pelvic glands and their functions. VIII. Nervous System. The faculty of receiving impressions from the outer world is common to all organisms up to man, but the possession of special organs for perceiving and conveying sensations (nerve fibres and nerve cells) does not extend to the lowest grades of the organic scale, for, though undoubtedly capable of sensation, the plants, the Protozoa and the lowest of the Ccelenterata (fixed Hydroidae, Lucernaria, Anthozoa) are constructed of tissue so differentiated as to exclude the possibility of the ultimate development of a nervous system. Such a structure is first found in the higher Ccelenterata, the Ctenophora and Medusae. The nervous system of the Ccelenterata, so far as has been ascertained, consists of ganglia, or small aggregations of nerve tissue, in the fundus of the digestive cavity, and nerve fibres proceeding from the ganglia. In the Medusae the system takes the form of a ring following the margin of the disc, and consisting of ganglia placed at regular distances, and nerve fibres connected with these ganglia. Such simple structures represent the fundamental type on which the nervous system of all organisms, from the Invertebrates up to man himself, is constructed. The nerve ganglia act as central organs receiving sensations by means of certain nerve filaments, and promoting action by means of others. The simplest example of this structure may be seen in those worms in which the body is not segmented (metameres) ; where, however, the body is articu- lated an almost uniform repetition of the central organs (ganglia) takes place. Moreover, the chief ganglia are, in all the worms, situated in the anterior part of the body, and herein we recognise the prototype of the central nerve organs of the animals of all the higher classes and orders. In the Echinodermata nerve trunks tapering towards the 150 THE HUMAN SPECIES ends are situated at the mouth or orifice for the admission of food, and in accordance with the radial structure are likewise radial. These radial nerves surrounding the mouth have been named by Joh. Miiller "ambulacral brain," and the term fitly describes the structure as compared with the true brain of the higher animals. With still more justice can we speak of a primitive brain in the Arthropoda, whose nervous system cor- responds on the whole to that of the Annelida, for of the two pharyngeal ganglia connected by commissures, the upper, or head ganglion, is always of more importance than the lower. Proceeding from the two pharyngeal ganglia, there is a chain of abdominal ganglia arranged in pairs and connected by com- missures ; sometimes, by means of transverse coalescence, these ganglia form an abdominal cord, corresponding to the spinal cord of the Vertebrates, and send off nerve fibres for the muscles, intestines and skin. In the insects the beginnings of a sympathetic system are evident, the system taking its rise in the abdominal ganglia and connected otherwise with the usual nerve fibres. In the Mollusca also a sympathetic system is present. At first sight their nervous system appears extremely complex, especially in the Bivalves, but closer examination reveals the fact that it is constructed on the same plan as that of the worms. It consists of two upper and two lower pharyngeal ganglia connected by commissures, and various distinctions are present, particularly with regard to the peripheral nervous system. As a rule, the nerve fibres proceed from the central parts of the pharyngeal ring and are connected with one another, and also with various independent ganglia. Distinctively characteristic of the Invertebrates are the gan- glia surrounding the oral aperture, and representing in their re- lation to the other ganglia a primitive order of central nerve organ, and distinctive of the Vertebrates is the symmetrically arranged nerve matter of undoubtedly central character enclosed in bony casement. In the Acraniata the nerve substance is dis- tributed equally throughout the entire length of the body ; in the Craniata it is divided into brain and spinal cord, but in all the Vertebrates alike the nerve masses originate in the upper blastoderm, first three and subsequently five consecutive cerebral NERVOUS SYSTEM KllKI vesicles being formed by expansion at the first section of the spinal canal. The cerebral vesicles are : the prosencephalon, thalamencephalon, mesencephalon, epencephalon and metence- phalon. These vesicles at first form a continuation of the longitudinal axis of the spinal cord, but subsequently stand at an angle thereto and remain connected with one another both durine o their original form and subsequently to their transformation into the different cerebral sections (ventricle, cavity of the brain)- The central canal of the spinal cord, which is developed from the posterior part of the primitive spinal canal, is similarly connected with the brain. In the lower classes of Vertebrates the medulla spinalis often exceeds the brain in bulk, but decreases in proportion as the brain develops. The centre of each half of the spinal cord consists of grey nerve matter with lateral processes (cor- nua) directed forwards and backwards (see Fig. 78). The peripheral nervous system FIG. 78 originating in the spinal cord is arranged according to the vertebrate articulation of the body ; from each vertebra springs a pair of nerves each consisting of two roots : an anterior (motor) and a posterior (sen- sory) nerve which unite together and form one trunk, dividing afterwards into two branches, a dorsal and a ventral nerve. Each of the extremities is supplied with a nerve plexus formed of a number of anterior spinal nerves ; for the anterior extremities there is the cervical plexus and the brachial plexus, and for the posterior extremities the lumbar, sciatic and brachial plexuses. There where the spinal nerves spring from the spinal cord protuberances appear in the latter, in the fishes to a slight degree but increasing in the higher Vertebrates (cer- vical, thoracic and lumbar swellings) (see Fig. 79)- A peculiarity possessed by man in common with the Am- phibians, Insectivora and Cheiroptera is the disappearing of the posterior section together with the formation of the so-called Fmp Transverse sec- tion of medulla spin- alis from the region of the back. Twice natural size. (Thom£, Zoologie.) Fma, an- terior ; Fmp, posterior longitudinal sulcus. Grey matter with cornua enclosed with- in white. Dark point represents spinal canal. 152 THE HUMAN SPECIES cauda equinaconsistingof spinal nerves which do not immedi- ately leave the vertebral canal but are contained therein for a part of their course (see Fig. 79). The Brain. Among the Vertebrates, the brains of fishes are of simple structure, especially in the lower orders, the five divisions of the brain corresponding in order to the five primitive cerebral vesicles. In the more highly organised forms a gradual de- velopment of bilateral, sym- metrical arches takes place, par- ticularly in the anterior or first vesicle, and later also in the second and third. The first vesicle (cerebrum) begins to overlap those parts posterior to it, and folds forming in its surface represent the first signs of convolution ; the posterior, or fourth, cerebral vesicle (cere- bellum) develops slowly ; the fifth vesicle (medulla oblon- gata) may be distinguished from the spinal cord by its breadth. In the amphibians the cere- bellum is divided laterally into two halves. During the larval state the differentiation of the second and third vesicles com- mences, the latter in the Anura increasing in bulk and dividing into two halves. The cere- Trunk of and cervical nerve Trunk of ist dorsal nerve Trunk of ist lumbar nerve Trunk of ist sacral nerve FIG. 79. Spinal cord ; front view. One-third of natural size. (Thome', Zoologie.) NERVOUS SYSTEM 153 bellum and medulla oblongata, however, remain somewhat primitive in type. Characteristic of the reptiles are the two curves of the brain, one occurring where the second vesicle separates from the third, the other in the neighbourhood of the medulla oblongata ; the separate divisions of the brain also increase in volume and in complexity of structure. The cerebrum with its two hemi- spheres covers the second vesicle and the lateral ventricles are well developed. The third vesicle (mesencephalon) is divided into two hemispheres by a deep fissure. In lizards and snakes the cerebellum is little developed, being more clearly differen- tiated in the tortoise and crocodile ; in the latter a median protuberance is distinguishable from the two lateral ones. In birds the cerebrum is more complex ; it consists chiefly of ganglion cells of the corpora striata, and with its hemispheres covers the small second vesicle. Here, too, the mesencephalon, or third vesicle, which is still of considerable size in the embryo, is divided into two halves as in the reptiles ; the cerebellum, however, is, in its middle part, still more highly developed than in the crocodile and almost completely covers the medulla oblongata. A glance at the embryonic brain of the mammals, with its manifold points of resemblance to lower forms, will show that we are not justified in assuming that an essential difference exists between the brain of the mammals and that of the lower Vertebrates. At a later stage of development extensive modifications take place, it is true, especially as regards the cerebrum, where the two hemispheres, separated from each other by a deep fissure, overlap the two olfactory lobes and are connected by a broad band of nerve tissue, the corpus cal- losum. Proceeding from the Monotremata up to the higher forms of life we find the cerebrum steadily encroaching on the mesencephalon, till finally, in the apes' and man, it covers the cerebellum. The second vesicle becomes the optic thalamus, the third the corpora quadrigemina, and the fourth, or posterior, develops into the relatively important cerebellum, the lateral lobes of which are developed, especially in the apes and man, at the expense of the middle lobe. '54 THE HUMAN SPECIES As the cerebrum increases in volume its surface begins to assume folds, and the convolutions and fissures develop, these being the standard of the position of the different orders in the organic scale. The anatomist Hu- schke,1 speaking of the importance of the convo- lutions, says : " The more complex the convolutions, the more impressions and branches they exhibit, the deeper thefissures between them, and the more sym- metrical their structure, the higher is the organ- ism ". Theconvolutions reach their highest development in man, the insula cerebri, for instance, only in man attaining its four to five fanlike branches. Now it is of special interest to ascertain in how far the human brain (in spite of a certain general cor- respondence) differs from the brain of those apes most closely resembling him. (See Plate iii.) An exhaustive study, " Ueber die typische Anordnung der Furchen und Win- dungen auf den Gehirn- hemispharen des Men- schen und der Affen " ( " On FIG. 80. Nervous system of man. a, cere brum ; b, cerebellum ; c, spinal cord ; on either side of the same the sympathetic ganglia. the typical distribution of the fissures and convolutions in the cerebral hemispheres of man and the apes "), has been published by Pausch, and a second 1 Huschke, Schddel, Him und Seele. Jena, 1854. NERVOUS SYSTEM 155 one by Ecker, " Ueber die Entwicklungsgeschichte der Win- dungen und Furchen der Grosshirnhemispharen im Fotus des Menschen " (" On the evolution of the convolutions and fissures of the hemispheres of the cerebrum in the human embryo ";, in the Archiv fur Anthropologie, iii., 1868. A comparison of the results of their investigations has been drawn up by Huxley, and incorporated by Darwin * in his work, On the Descent of Man. Huxley gives the following definitions : — (1) In the human foetus the fossa Sylvii develops in the course of the third month. During this period and in the fourth month the hemispheres of the cerebrum are smooth and rounded in form and project far over the cerebellum. (2) The true fissures first make their appearance between the end of the fourth month and the beginning of the sixth. This, according to Ecker, varies individually. In no case are the frontal or temporal fissures the earliest to appear. The first fissure is either the occipito-parietal or the Hippocampus major. (3) Towards the end of this period the fissure of Rolandi is developed, whereupon follow in the course of the sixth month the chief fissures of the frontal, parietal, temporal and occipital lobes. Hence Huxley concludes that man is descended from an ape-like type and moreover from one which differed in many respects from all members of the existing order of Primates. The brain of the human embryo in the fifth month may be said to be not merely the brain of an ape but the brain of an Arcopithecus, or of a member of the Marmoset species, though it differs from that of all existing Marmosets by virtue of its open fissure of Sylvius. With respect to the true Platyrrhines, Pausch records that in the brain of an embryonic Cebus Apella only one very shallow fissure was found in addition to the fissure of Sylvius and the Hippocampus. Of great interest in studying the origin of the human brain, is the fact that before temporal, or frontal, sutures appear, the foetal brain of man presents characters otherwise only found in the lowest groups of the Primates (apart from the Lemuridae), and this is precisely what we are led to expect on the theory that man has been 1 Darwin, loc. cit., v., p. 266. 156 TH"E HUMAN SPECIES evolved through graduated modifications from the same type as that from which the rest of the Primates have sprung. As early as 1866, in his Lemons sur la Physiologic (p. 890), Vulpien remarks : " Les differences reelles, qui existent entre 1'encephale de 1'homme et celui des singes superieures, sont bien minimes. L'homme est bien plus pres des singes anthro- pomorphes par ses caracteres anatomiques de son cerveau, que ceux-ci ne le sont seulement des autres mammiferes, mais meme de certains quadrumanes, des guenons et des macaques." * In Huxley's opinion, the anatomical differences between the brain of the highest apes and that of man consist, broadly speaking, of the superior size, absolute and relative, of the hemispheres of the human cerebrum, as compared with those of the orang and chimpanzee, in the smaller cavity of the human frontal lobes, caused by the upward projection of the supraorbital ridge, in the abundance of the human convolutions and fissures of the secondary folds together with less symmetry in their order and in the usually slight development of the human tempero-occipital fissure. As further distinction Wiedersheim - adduces the fact that the third frontal fold in the anthropoid brain differs from that of man in that a small, isolated gyrus occurs at the base between the sulcus fronto- orbitalis and the sulcus opercularis. This gyrus forms the surface of the insula cerebri. In all apes the insula lies deep and shows an inferior development to that of man. The anterior region of the insula, like the operculum, has been acquired during the later periods of man's history undoubtedly in connection with the development of the organs of speech (see Fig. 81). The finer anatomical distinctions in man's favour are based on differences in the structure of the cortex cerebri, the most important psychical organ. With respect to the structure of the brain, the mammals are divided into two great classes, the Gyrencephala and Lissencephala. In the Gyrencephala (apes, 1 " The actual differences existing between the brain of man and that of the higher apes are extremely slight. Man is much nearer the anthropomorphous apes, as regards the anatomy of his brain, than are the latter not only to the other mammals but even to certain of the quadrumana, the long-tailed monkeys and the Macacus species." 2 Wiedersheim, loc. cit., p. 137. PLATE III. Brains of mammals and of man. M M, German; L, Bushman; K, Gorilla ; I, Orang; H, Chimpanzee; G, Gibbon. NERVOUS SYSTEM '57 beasts of prey, Ungulata, etc.) the convolutions are relatively well developed ; in the Lissencephala the cerebrum does not cover the cerebellum, and the convolutions are either very slightly developed, or are completely absent. To this class belong the Cheiroptera, Insectivora, Rodentia and Edentata. Hermanides and Koppen have published l an admirable work Com SM Cop Ccl3 S. Ccl2 Ccl1 Cba Cbl Tc Vq Fp FIG. 81. Median section of brain. (Two-thirds natural size.) Vq, Fp, Fourth ventricle ; Mo, Medulla oblongata ; P, Pons Varoli ; Cca, Corpora mam. ; Tc, Tegmentum of grey matter ; H, Hypophysis ; H1, Optic chiasma; H2, N. opt. ; Let Grey com. bas. ; Cos, Comm. ant. ; Cba, Comm. bas. alb. ; Ccl1, Anterior end ; Ccl2, Genu ; Ccl3, Body ; Ccl4, Posterior swelling of corpus callosum ; FM, Foramen of Munro ; St, Septum lucidum ; Com, Median commissure ; SM, Sulcus Monr. ; Cop, Posterior commissure ; Cn, Pineal gland; Lq, Lam. quadrig. ; A, Aqueduct Sylv. ; Fta, Fissura cer. ant. ; Vma, Vel. med. ant. ; Cbl, Cerebellum. on the fissures and structure of the cerebral convolutions in the Lissencephala. These two authors, after investigating the brain of the rabbit, rat, mouse and mole, have obtained the following results : — (i) In these animals there exist fissures so connected with the cortical structure that where they occur either the cells 1 Archiv fur Psychologie, 37, 2. Fta .Vma 158 THE HUMAN SPECIES are arranged in a special order or the cortical structure as- sumes a new form. (2) In the structure of the cortex there are several distinct types to be recognised : the motor type, the type of the upper occipital cortex, that of the optic region and that of the olfactory cortex. The distinction between these various structures is shown by the differences in the strata of the large cells (stratum of the large pyramid cells in man), in the presence of the stratum granulosum and in certain peculiarities of the stratum of small cells (small pyramid cells in man) lying immediately under the molecular layer. (3) In the cerebrum a transverse fissure was found, a second occurring near the occipital pole, its position bearing a striking resemblance to that of the fissura occipitalis. It marks approximately the boundary between the cortical region named " motor " by the authors, and that situated nearer the occiput, and hence termed by them the upper occipital cortical region. (4) A fissura occipitalis in the lower surface of the occipital lobe in the rabbit is probably identical with the fissura calcar- ina. The cortex is here distinguished by the presence of innumerable granule cells, closely crowded together and separated from the molecular stratum only by a thin layer of dark-coloured large cells. In the other lissencephalous animals subjected to examination the stratum granulosum was not so highly developed as in the rabbit, but was nevertheless clearly recognisable. (5) The fissura rhinalis marks the commencement of a very striking modification in the cortical structure, indicated by the abundance of dark, large cells in the second stratum, and by the narrowness of the fourth cellular layer. In those cases where a distinct fissura rhinalis is absent the same abrupt change in the cortex nevertheless appears in the corresponding place. (6) In the posterior cornu large, dark-coloured ganglion cells are found with large and long-pointed processes, which occur nowhere else in the whole brain. (7) The results of the investigations show that the study of the structure of the cerebral cortex, which varies greatly in character, is of the highest importance in studying the con- NERVOUS SYSTEM 159 struction of the cerebrum of the various animals and must always be taken into consideration in homologising the fissures. A comparison of the weight of separate portions of the brain with that of the large hemispheres, or of the entire brain, yields very instructive figures. Thus Meynert (following Joh. Muller) takes the proportion borne by the cerebral hemi- spheres to the corpora quadrigemina as the unit of measurement, and finds that in proportion as the hemispheres develop, the peduncle of the crus cerebri (containing the voluntary motor nerves) surpasses in bulk the tegmentum of the crus cerebri. On the authority of Huschke,1 the weight of the optic thalamus and corpus striatum is as follows :— °/0 of the weight of the cerebral hemispheres. 13 calf „ „ sheep 14- 1 5 ,. Huschke 2 has further tabulated the proportion of the cere- bellum (Vermis, lobes, Pons Varoli and Medulla oblongata) to the entire brain. His results are the following :— In man . . . 12-13 °/0 cerebellum. „ the gibbon . . 13-91 „ „ „ „ cow 12 „ „ „ dog . 11-17 ,. „ „ horse . . 15-17 „ „ „ fox . . 15-18 „ „ „ goat . 17-18 „ „ „ Pig- i» ,. „ „ sheep . . 17-21 „ „ ii „ bear 19 „ „ „ cat . . . 20-23 „ „ „ „ rabbit . 24 ,, „ „ „ rat . . . 25-27 „ „ ,, duck-bill . . 25 „ „ „ „ raven . . 10-13 •• » „ „ wood-pecker . 14 „ „ Huschke, loc. cit., p. 104. *lbid., p. 73. 160 THE HUMAN SPECIES As to the proportion of the Rons Varoli (Fig. 82) to the cerebellum, the higher the mammal stands in the organic scale the narrower and shorter is the Pons Varoli in proportion to the cerebellum.1 Man possesses the broadest cerebellum, the next in order being the cats, and then, although at some distance, the ruminants. Each lobe of the cerebellum in man as in the animals consists of six parts. The difference between man and the mammals consists in the medulla being much less extensive in man than in the animals, and the central lobe in man occupies a more central position. In man, too, the vermis is somewhat triangular in shape, the apex of the triangle being posterior. A further study of comparative anatomy shows that the vermis and the cerebellar hemispheres in man develop in inverse ratio to the same in the animals. In fishes the cerebellum begins with the formation of the vermis, while in birds and mammals the hemispheres are developed at the cost of the vermis. In the lower mammals the cerebellum gradually becomes circular in shape, owing to the increasingly lateral position of the hemispheres ; in the higher mammals it in- creases in breadth, and finally, in the apes and man, attains its characteristic transverse expansion. Huschke2 gives the following figures for the proportion of the vermis to the hemispheres : — Otter . . 2 5 '6 °/0 vermis 74-4 °/0 hemispheres. Pig • • 32'8 „ „ 67-2 „ Dog . 39-42 „ „ 61-58 „ Fox . . 437 „ „ 56-3 „ Horse . 45-54 „ „ 55-46 „ Cat . 47-51 „ „ 53-49 „ Goat . 50 „ „ 50 „ „ In the anthropoids the cerebellum usually projects from under the margins of the occipital lobes, owing to the cerebellum being particularly broad, but in man this rarely occurs. On the other hand, the vermis of the human cerebellum is invariably more perfectly developed than that of the anthropoids. The thickness and curve of the corpus callosum (see Fig. 81) bears an exact proportion to the height and curve of the cere- 1 Huschke, loc. cit., p. 85. *Ibid., p. 77. NERVOUS SYSTEM 161 bral lobes. In the mammals as compared with other animals the corpus callosum increases in thickness rather than in length. Let Pec Tl, Cba Tc pa Cca FIG. 82. Human brain viewed from beneath. P, Pons V. ; Tbo, Tractus opt. ; Lpp, Grey lamina between Pons V. and corpora mam., Cca ; * In, Insula cerebri : marginal elevations of deep cerebral stratum ; Tc, Tuber ciner. ; Tbo, Tuber olfact. ; Let, Grey commissure; Ccl2 and Pec. Parts of corp. call.; Cba, White basal commissure ; Spa, Transverse gyrus consisting of white substance interspersed %vith vascular orifices ; Cca, Corpora mamm. ; Gf, Cerebral gyri ; T, Tegmentum of grey substance; B, Crus; Sr, Reticular white substance of the temporal lobe ; Mo, Medulla obi. The Roman figures represent the cerebral nerves. The hypophysis is absent. In proportion to the thickness of the human corpus callosum, which corresponds to the greater height of the human brain, ii 1 62 THE HUMAN SPECIES the corpora callosa of the other mammals are thin.1 In all Vertebrates the medulla oblongata, originating in the fifth cerebral vesicle, exists previous to the formation of the Pons Varoli ; in proportion, however, as the matter increases, it being the more vital part of the brain, the medulla oblongata is less prominent.- Two peculiar cerebral formations which have recently aroused special interest have still to be considered. These are the hypophysis cerebri and the glandula pinealis. In man peculiar conditions prevail with respect to the hypophysis. It is worthy of remark that the cavity in the hypophysis, corresponding, to a certain extent, to a sixth ventricle, has almost disappeared in man, and the organ is comparatively small. Huschke 3 gives the following figures for the proportion of the hypophysis cerebri to the cerebrum : — In man = i „ beasts of prey = i „ the pig = i „ „ horse = i ,, „ rodents = i ruminants = I 2304 723-960 450 352 104-360 77-121 52-99 „ „ birds = i In animals the hypophysis consists of an anterior lobe, having the character of a vascular gland, and a small posterior lobe of grey matter containing nerve fibres in its fine-grained, nuclear tissue. Tumours and other diseases arising in the tissue of the hypophysis are associated with the occurrence of acro- megaly ; I do not know whether the same conditions have been observed in animals. The glandula pinealis, which is situated on the anterior pair of corpora quadrigemina, has from the earliest times attracted the attention of anatomists far more than has the hypophysis ; indeed, the philosopher Descartes4 raised it to the dignity of the seat of the soul. Although we can hardly attribute so great a significance to it nowadays, it has attracted the notice of anatomists from another point of view, in that it has been 1 Huschke, loc. cit., p. no. *Ibid., p. 85. 3 Ibid., p. 106. 4 Descartes, Les passions de I'dme, 1649. NERVOUS SYSTEM 163 recognised as the homologue of the so-called parietal organs of the other Vertebrates. There is an exhaustive work on this subject by Dr. Studnicka in Oppel's Text-book of Compara- tive Microscopic Anatomy, Part V.1 By the term " parietal organs" are apparently understood unsym metrical structures, in saccular or vesicular form, arising by means of protrusion from the cerebral cortex, or in the roof of the mesencephalon, and originally serving to receive and transmit sensations of light ; in the majority of Vertebrates, however, they contain but the merest rudiments of organs for the reception of light, and are finally transformed into organs of an entirely different character, namely, into glandular tissue of unknown function. As a rule the parietal organs tend to lie superficially, and at this point the skull becomes markedly attenuated ; indeed, an opening sometimes occurs in the bone or in the cartilage (foramen parietale). In the region of the parietal organ the tissues are much more transparent and colourless than else- where. Almost invariably a close connection with the brain is found, and the organ is generally enclosed in the interior of the skull. In certain of the Vertebrates (e.g., Anura) the parietal organ lies above the roof of the skull, immediately under the skin. The general structure of the parietal organs corresponds to their origin in a protrusion of the cerebral lining and to their original function of (unsymmetrical) visual organs. The walls are found to be constructed of the same elements as those composing the nervous parts of the cerebro-spinal canal and the retina of the permanent eyes. The lens-cells of the parietal eyes resemble those of the true eyes, and the content of the lumen of these primitive eyes may be considered as the rudiments of vitreous bodies.2 Following, in the light of Studnicka's treatise, the parietal organs from the lowest to the highest classes of the Vertebrates, we are not astonished to find the Cyclostomata (with the ex- ception of the Myxinoides) furnished with well-developed parietal eyes in the form of pediculated vesicles with a retina, or so-called Pellucida, and even a plano-convex lens. 1 Dr. Studnicka, " Die Parietalorgane der Wirbeltiere," Oppel, vol. v., 1903. 2 Studnicka, loc. cit., pp. 9, 10. II * 1 64 THE HUMAN SPECIES The position of the parietal eye in the Petromyzon species is indicated by a white parietal spot between the permanent eyes, and by the epidermis and corium being destitute of pig- ment.1 In the Selache the vesicle has neither retina nor pellucida nor a true cornea, and only in the Spinax is a parietal spot without pigment to be recognised. - The parietal organ has the same form in the Ganoidea, but in the Teleostei it is a somewhat reduced organ, very de- fective in structure, without cornea and parietal spot, connected with the roof of the skull either by the distal extremity of the terminal vesicle, or by the entire upper surface of the same, whereby the roof of the skull is rarely perforated.3 Of still simpler organisation is the parietal organ of the Urodelian amphibians, being merely a sac with slight folds, lying in close proximity to the roof of the mesencephalon, but, on the other hand, the conditions prevailing in the Anura prove beyond a doubt that their progenitors possessed parietal eyes, for the white parietal spot between the existing eyes is, with very few exceptions, plainly visible.4 In reptiles the parietal organ varies greatly. Of the two parietal organs of the Saurians and Prosaurians only the anterior organ can claim to be a true parietal eye, but this claim has far more justice than in the case of any other vertebrate, for, where it does occur, all the attri- butes of the true eye are present, namely, the cornea above the foramen orbitale, lens, retina and pigment, and a corpus vitreum. and the nerves connected with the brain are clearly recognisable (see Fig. 83).5 Contrasted with this third eye of the Saurians the parietal organ of the Ophidians is only a solid structure abundantly furnished with blood vessels with a strand of nerve fibres in its peduncle, and is probably to be considered as a secreting gland. Of a foramen parietale and a parietal spot there is no trace.6 Nor can the Chelonia and crocodiles be said to possess a true parietal eye, only rudimentary sac-like appendages to the cerebral cortex being present without peduncle. Rudimentary 1 Studnicka, loc. cit., pp. 42-44. zlbid., p. 48. 3 Ibid., pp. 82-85. 4 Ibid., pp. 110-120. 5 Ibid., pp. 134-198. 6Ibid.. p. 199. NERVOUS SYSTEM 165 also is the corpus pineale of the birds ; it is either large and in the form of a sac, or small and constructed of follicles, or quite solid. In the embryos of certain swimming birds temporary rudiments of a parietal spot are present in the form of a small pigmental area, while only in the crested goose is the skull perforated by a foramen parietale above the place of the parietal organ. In mammals the parietal organ is a solid, conical body, wherein but a proximate part of the earlier lumen is present. A special peduncle is generally absent, except in the common chimpanzee, where the conditions are still simpler FIG. 83. Sagittal section of the parietal eye, parietal nerves and distal extremity of the epiphysis of an almost mature embryo of Hatteria punctata. (Oppel, Vergl. mikr. Anat., Part v., Fig. 83.) Pa, Parietal eye; Npar. Parietal nerve ; Ep, Epiphysis. than in man.1 In man the upper surface of the organ is uneven, in all other mammals it is smooth. The form of the parietal organ is liable to vary ; thus in the pig it is spindle-shaped and elongated, in the sheep pear- shaped, in the dog flat, and in man (see Fig. 84) conical, with the apex directed backwards. The human pineal gland measures sagitally 8-12 mm., transversally 6-8 mm., and is larger in the female sex than in the male sex. but in the former weighs only 0*00012 per cent, of the entire weight of the cerebrum. JStudnicka, loc. cit., pp. 210-219. i66 THE HUMAN SPECIES In structure the organ consists of a framework of connective tissue furnished with cells containing pigment bodies, of striated muscular fibres, blood vessels, nerve fibres and ganglion cells. The so-called brain-sand, traceable in the parietal organ of the Cyclostomata, and consisting of minute particles of carbonate of lime, phosphate of lime and magnesia, which was formerly considered of great importance, is found in man and in certain of the mammals. Neither man nor any of the mammals pos- sesses a foramen parietale, but Studnicka is inclined to regard <• > FIG. 84. Epiphysis and surrounding parts of the skull of a child of twelve years. Ep, Epiphysis ; R, Recessus pinealis ; Cp, Commiss. post. (Oppel, Vergl. rnikr. Anat., Part v., Fig. 123.) the white parietal spot as well as the similarly placed pigmented areas of certain animals (e.g., horse) as rudiments of a parietal spot.1 In conclusion we must mention as parts of the brain those cerebral nerves originating therein which, when completely developed, consist of twelve pairs. In spite of a general corre- spondence, certain distinctions are still to be noted between the higher and lower Vertebrates. Thus in the fishes, amphibians, birds and Monotremata, the nerves springing from the Bulbus olfactorius unite into a trunk, whereas in the higher mammals 1 Studnicka, loc. cit., i., 450. NERVOUS SYSTEM 167 and in man they pass singly through the Lamina cribrosa. In the Cyclostomata, on the contrary, each optic nerve passes separately to the eye subsequent to the formation of a com- missure near the point of origin, while in the other Vertebrates an optic chiasma is always present. It must moreover be re- marked that only in the reptiles, birds, mammals and man do the oculo-motor, trochlear and abducens nerves leave the brain separately and remain separate throughout their entire course. The vagus, which appears in the reptiles (snakes excepted), is closely connected with the accessories only in the higher Vertebrates and in man. The rest of the cerebral nerves present no points of difference among the various classes of Vertebrates. Having discussed the separate parts of the brain from the standpoint of comparative anatomy, it remains only to examine the entire mass of the human brain as compared with separate parts of the body, and with the weight of the entire body. On the authority of Vierordt l the absolute weight of the brain of an individual of twenty to thirty years is : — In the German man 1,461 gm. ; woman 1,341 gm. „ „ English „ 1,412 „ „ 1,292 „ „ „ French „ 1,358 „ „ 1,230 „ „ „ Swiss „ 1,350 „ „ 1,250 „ „ „ Russian „ 1,346 „ 1,195 „ Davis has drawn up tables according to the races. He gives as the average absolute weight of the brain : — European man 1,367 gm. ; woman i,2O4gm. Oceanian „ .1,319 „ „ I,2I9 » American „ 1,308 „ „ 1,187 „ Asiatic „ 1,304 „ „ 1,194 „ African „ 1,293 „ „ 1,211 „ Australian ,, 1,214 ,, „ 1,111 „ The figures show that the male brain is on an average 9 per cent, heavier than the female. The increase of size in the human brain due to its convolu- tions (as contrasted with a smooth, unconvoluted brain) Dumou- lins reckons as twelve-fold. 1H. Vierordt, Anatomische, physiologische und physikal. Daten und Tabellen. Jena, 1888. P. 39. 168 THE HUMAN SPECIES The most important point is the large number of cortical ganglion cells, of which about 2,000 millions (approximately I million to the centimetre) are situated on the cortex of the cerebrum, and about 10 millions in that of the cerebellum.1 On the authority of several anthropologists (Broca, E. Schmidt and A. Schmidt) there can be no doubt that the great weight of the brain among civilised nations is a direct result of civilisation. Broca examined the skulls of Parisians from the twelfth and the thirteenth centuries and compared them with skulls of the nineteenth century, and states that the capacity has considerably increased in the course of the centuries. E. Schmidt compared skulls of ancient Egyptians with those of modern Egyptians, and obtained what at first sight seems an opposite result, the modern Egyptian showing the smaller capacity. The apparent contradiction is in reality but a further proof of the theory, since the decrease in capacity is to be ascribed to the decay of the Egyptian civilisation. Buschan - extended his investigations to the neolithic skulls of France and the Rhine provinces, and obtained the same results as Broca with respect to the capacity of the skulls ; his research enabled him further to state that the frontal suture remains open in proportion to the increase of capacity following the rise and extent of culture. Moreover the brain varies in size among the civilised nations according to class and profession. Buschan gives the four following classes : — (1) Day-labourers, workmen. (2) Mechanics, artisans. (3) Tradespeople, clerks, teachers, lower officials. (4) Scholars and higher officials. Taking the figures obtained by Matiegka (Prague), Buschan reckons that a weight of 1 ,400 gm. is attained : — In the 1st class in 26*2 % of cases. ,, ., 2nd „ „ 42*8 „ „ „ „ „ 3rd „ ,,48'5 » „ )> » 4^ft » " 57 ^ » » )> 1 H. Vierordt, loc. cit., p. 44. 2 Buschan, Archiv fur Rassen- und Gesellschaftsbiologif, i., 5. NERVOUS SYSTEM 169 According to Spitzka, the brains of mathematicians and astronomers are heavier than those of any other class of in- tellectually cultured men. Ranke l gives some very instructive tables on the authority of Carus, Joh. Miiller and v. Bischoff, on the relative weight of the brain, i.e., the proportion borne by the brain to the rest of the body. In small Middle European singing birds ., the tufted capuchin .... „ .. common marmoset „ „ common squirrel-monkey . „ „ smooth-headed capuchin „ „ magpie „ „ rat . „ „ wan- wan gibbon .... „ „ German (woman) „ „ mole „ ., German (man) .... „ ,. teetee monkey .... „ „ lemur ..... „ ,. half-grown orang „ „ „ chimpanzee , cat macaque adult gorilla tapir . pigeon eagle . lizard . frog . dog . carp . fowl . sheep goose . salamander horse . young elephant 12-28 13 22 24 25 28 28 28(-48) 35 36-16 42 82(-i56) 96 1 04 (-170) 104 1 60 r6o 1 60 172 2i4(-304) 248 347 35i 380 40o(-7oo) 500 1 Ranke, loc. cit., i., p. 535. 170 THE HUMAN SPECIES In the tiger and lion i 5oo(-6oo) „ „ ox i 5oo(-8oo) „ „ gadus lota . . . . i 720 „ „ ostrich i 1,200 „ „ land turtle . . . . i 2,240 „ „ shark i 2,496 „ „ sea turtle i 5,680 „ „ tunny . i 37,440 The comparatively great weight of the brain of small singing birds and of the small apes and monkeys is very striking, but it has been ascertained that in man also small, light individuals possess relatively heavy brains. From the above scale it is clear that man does not possess the heaviest brain in proportion to the weight of his body, nor has he, as Aristotle taught, even the greatest quantity of brain in proportion to his size (Kara //,e7eSo civilisation which had formerly flourished there. •j The final victory of iron in mid-Europe must be reckoned from the beginning of the fifth century B.C. The locality after which this period is named is La Tene, a place on the Lake of Neuenburg, where on the bottom of the lake a whole stratum of beautifully made iron weapons, tools and ornaments has been found. The iron industry attained its greatest develop- ment under the Romans who became successors to the civilisation of La Tene, and spread their manufactures over all the countries of which they became possessed. Among utensils, or useful objects, one of the most useful, owing to its portability, is earthenware; it is also of great ARTS AND HANDICRAFTS 327 antiquity, and a special product of man. The mere working and kneading of earth and clay is, however, no special inven- tion of man's ; long before men made pottery, animals existed which knew how to make dwellings or nests as cradles for their offspring out of damp earth or clay mixed" with saliva. Thus, among insects, certain bees (Chalicodoma muraria) and wasps (Odynerus parietum) ; among birds, the jackdaw (Corvus monedula), woodpeckers (Xenops genibarbis), nuthatch (Sitta caesia), thrushes (Turdi), and certain swallows (Hirundo rustica), and martins and the Australian ariel (Chelidon ariel). All these animals can mould and knead excellently ; they can raise layer on layer, and construct their dwellings with the tools given them by nature in a manner suitable to their require- ments. The manufacture of an earthen vessel by the hand of man was, of course, a greater feat than any of these ; but the fragments of clumsy vessels which are found in the transitional states between the palaeolithic and neolithic, show that in their first beginnings these were of a very primitive kind. How it was that palaeolithic man did not make clay vessels although surrounded by plenty of rich clayey soil, will always remain an anthropological puzzle. We may indeed assume that man first carried his water supply in bone jpans and_ the.- skull-caps of animals, or in vessels of wood and hide which have Jong since perished ; or he may have used vessels of plaited osiers, as do the Terra del Fuegians at the present time. Well-made vessels of osier have been thought by some authorities (Ranke and others) to have suggested the making of pottery ; man discovered that vessels, the interior of which had been lined with clay, were much more water-tight. Acci- dentally, one such clay-lined vessel was put on the fire ; the osiers were burnt off, and the first piece of baked pottery was manufactured. Potsherds have indeed been discovered on the outer side of which is the impression of basket-work, but the principal ex- amples were carried out on pottery after the properties of clay had become known. Man, most probably, in different parts of the earth, got the idea of making his vessels for fluids and for dry provisions out of this convenient material. A glance at the way in which water will remain all day long in the hoof- 328 THE HUMAN SPECIES mark of a wild animal on a clayey soil showed him at once the impermeability of clay ; its plasticity was illustrated when he noticed how the impress of every finger which he placed on it remained, and he realised how it could be modelled into any desired shape. The clay vessels simply moulded by hand in a primitive manner were soon doomed to destruction. Later on he accidentally observed that any vessel which had been exposed to the fire for a long time exhibited a much greater hardness and durability. The first rude potsherds are found in transitional localities between the palaeolithic and neolithic periods, such as the cave of Mas d'Azil in France, and in the kitchen-middens on the shores of the " Ostsee " in Norway. From that time to this clay vessels have been manufactured wherever clay is obtainable. Pottery has never been known to the Eskimos, nor to the Northern Indians of North America ; nor to the Botokudes and Kayapos, in Brazil, nor the tribes of the pampas and Terra del Fuego, in South America ; nor to the Veddahs in Ceylon, the inhabitants of the mainland of Australia, the Maoris in New Zealand or the Polynesians. In most of these cases, but not in all, the cause of this is that the soil contains no suitable clay upon its surface. In all other regions of the earth pottery, at first simply hand-made, and later turned on a wheel, has risen from the simplest to the most elaborate forms, being gradually improved, partly by individual invention and partly by imitation of imported articles. Many potters indeed of the present day find it very difficult to manufacture on the wheel the same beautiful wide-bottomed vases which the men and women of old times made with a sure eye and free hand. Potteiy was made by hand in this way in mid-Europe up to the period immediately preceding the Roman. At first, the squat, thick-sided pots had generally a spherical shape, almost like the pumpkins of Southern climes. As time went on they were better shaped, and stood more firmly on even bottoms (Figs. 158 and 159). Better clay, too, was used, which was polished after the vase was finished, and soon became ornamented with some simple design. Handles were soon added, and plates, cups and pitchers were made. Finally, during the Hallstatt period, richly decorated and coloured urns ARTS AND HANDICRAFTS 329 and plates were placed with the dead in the graves, and these even now may excite our wonder and admiration. There were two ways in which the potters (who were the women) could carry out their object. They could either work from a lump, that is. from a mass of clay already roughly cut to the size required, or they could construct a vessel by degrees by building up or sticking together small pieces one upon another. In the first method the tools used in hollowing out the lump of clay were either the fingers, or else the elbow which was twisted round in the mass : or a mallet was used to beat FIG. 158. Neolithic pottery from South-west Germany. (After Schiiz.) and hammer it from within outwards, while with the left hand it was held on one of the so-called anvil stones. Still simpler is the method of working on the lump employed by the inhabi- tants of the Andaman Islands, who merely scrape out the mass of clay layer by layer with a mussel shell until the pot has attained the desired shape. The method of gradually building up small pieces of clay is the converse of this; the woman either lined the walls of a hole in the earth with a layer of clay, or else, on a hand-made bottom, she piled little rolls or lumps of clay and modelled it into layers with both hands. The polish was attained as it is now among primitive peoples by rubbing with mussel shells or smooth pebble stones. 330 THE HUMAN SPECIES Afterwards the vessels were allowed to dry and then burnt either on the open fire, or, in later times, in clay ovens. In the East (Asia and Egypt), brick ovens were used from the earliest times. Clothes^ Plaiting and Weaving. — Animals carry their clothes on their bodies, as scales, feathers or hair. Man has to make clothes for himself in order to cover his naked body, and to protect himself from the cold. This is a characteristic difference between man and beast. There are indeed many savage races in the tropics who go about either entirely naked, or clothed only with a loin cloth. Antediluvian man, however, had to protect himself against considerable changes of temperature, and to see that his body FIG. 159. Neolithic pottery from South-west Germany. Vessel of the goblet type. (Swabian Exploration Reports, VII.} was kept warm. Obviously it is impossible to say whether any feelings of modesty, such as generally distinguish man from animals, were experienced as early as this. In the drawings of the prehistoric reindeer hunters man appears naked, but the large number of flint instruments for skinning found in palaeolithic deposits show that he wore clothes, and that these were made of the hides of the animals he hunted. These hides must have undergone some kind of preparation to make them soft and supple. A sort of tanning, by means of rubbing and pounding the brains of a slaughtered animal on the inner side of the hide is, according to Conservator Krause of Berlin, of great antiquity, and produces a very soft leather. In the Bronze Age tanning with alum was known, as Olshausen noted in the leather found in the barrows of Amrum. O. Schrader, ARTS AND HANDICRAFTS 331 from the etymological point of view, states that tanning is one of the primitive arts. The hides of the prehistoric men were stitched together with the bone needles so frequently found in palaeolithic deposits. The holes for laces were bored by awls found in the same places, and made of the shin bones of animals ; the so-called sceptres of reindeer horn richly decorated, and provided with a large hole, apparently served to hold their clothes together across the breast. If palaeolithic men also inhabited tropical and subtropical regions, they must have made their clothes of bark, leaves and grasses, as do savage races to-day. In the matter of clothes the great contrast between the older and newer periods of the Stone Age is extremely well marked. In the Danish kitchen-middens spinning-wheels are found, and it may be gathered from this that the art of spin- ning (? flax) was by that time known to the neolithic people of the North. The spinning of threads is, however, no special acquisition of man, because, as Brehm points out, the tailor bird (Orthotomus longicanda) stitches together the leaves which form its nest with threads which it spins itself from the raw cotton. It was a longtime before man learned the art of spin- ning, but when he had once acquired it, he at once made great progress, by making his threads into plaits and these again into a woven texture. Such materials made by the antediluvian man we do not actually possess, as they only exist in the indestruct- ible representations of them found in Kesslerloch and the caves of Freudenthaler. It may be doubted, therefore, whether they were made of vegetable fibres, as neither spinning-wheels nor any fragments of such-like fibres belonging to this period have been found. It must be assumed, therefore, that sinews formed the original material for threads, and that with these their garments were held together, as are those of the Eskimos at the present time. We have more certain indications of the use of self-spun flax in the period of pile-buildings, for numerous spinning-wheels have been obtained from the bottom of the lake, as well as plaited and braided work, and also looms and woven material (Fig. 160). The braided work was always the older and simpler, and was followed later by the more com- plicated woven material made on an upright loom, such as is 332 THE HUMAN SPECIES now used by the negroes in West Africa. In the materials found at Robenhausen there are stuffs woven with woof and warp, which, owing to the character of the lake bottom, have been very well preserved. Originally wool was not used either for spinning or weaving. There are no traces of a woollen industry among the dwellers in pile-built houses, although they possessed domesticated sheep. Possibly the wool was used for other purposes, such as being made into felt with the hair of other animals, although felt of this kind is not found in the lake villages, but first appears in the northern tree coffins of FIG. 160. Plaited and woven work, spindles and spinning-wheels from the Swiss lake villages, i, basket-work; 2, mat; 3, net; 4, spun threads; 5, woven material ; 6, thread and plait ; 7, spinning-wheel ; 8, spindle and spinning- wheel. the Bronze Age, where the bodies are clothed in felt mantles, woollen coats, woollen jackets and woollen caps. Examples from the Hallstatt period show the men partly with short coats and partly with long mantles, and the women clothed in jackets and habits with capes. Whether these were woven of vegetable fibre or wool, cannot be made out on account of the few fragments of clothes which have been discovered. It must be remembered, however, that man has no mono- poly of the art of spinning. The same is true of plaiting and weaving, for quite apart from spiders and silkworms which spin and weave, there are many birds which are adepts at these arts, DWELLINGS 333 such as the weaver bird (Plocei), the golden oriole, the titmouse (Aegithalus pendulinus), the Chinese titmouse (Orites caudatus), and others ; there is also a small mammal, Mus minutus, which constructs an elegant nest of threads between the stems of plants. Dwellings. — Homes regards the tree-dwellings and huts made of interlaced boughs and stems, and furnished with a roof, as the type which most nearly resembles those of the beasts. It is probable that palaeolithic man constructed much the same huts in trees as do the Battas in Sumatra, certain South Indian and Malay races, and some of the very low tribes in South Africa to-day, but we have no positive evidence of this (Fig. 161). If it was so, the men of that time differed but little from the anthropoid apes in the matter of their dwellings. According to Brehm,1 the gorilla, the chimpanzee and the orang spend the night in nests, 20 to 30 feet above the ground, constructed of branches intertwined, and made comfortable with boughs and leafy twigs. Practically, the nest of the orang resembles that of a great bird of prey, and similarly is never provided with a roof. Thick boughs are either broken off, or bent and twisted together, interwoven with loose, leafy branches, and made impervious with foliage and grasses. Similar nests are constructed by many birds, such as jays, bullfinches, ravens, carrion crows, rooks, the American blue jay, the redwing, whereas the magpie, and also the squirrel, provide their basket-work nests with a roof. There are, however, many simple animal dwellings of which primitive man might have availed himself, as for instance, hollow trees, clefts in the rocks, or caves in the mountains. That man actually lived in caves like the beasts of prey well into neolithic times is evidenced by the numerous discoveries of fire-places and manufactured objects of all kinds deep in the limestone caverns of the European mountains, often " petrified " by lime salts. . Many authorities assume that caves were only used in the winter, because hunter-tribes for the best part of the year settled here and there in suitable spots where they erected temporary dwellings. This view, which has much in its favour, has been recently supported by a remarkable discovery. Among 1 Brehm, loc. cit., i. , p. 25. THE HUMAN SPECIES the many pictures on the walls of the Grotte des Vezeretales in France one was found showing a hut, built of stakes and pro- vided with a roof, showing that man at that period was able to do carpenter's wrork with his primitive tools. Like certain FIG. 161. Tree-dwelling from Southern India. (Homes.) savage races of to-day (the Hottentots, Gallas, Somalis, and Terra del Fuegians), he could cut off the stronger twigs or thinner branches, place them crosswise in the earth, fasten them at the top, and intertwine brushwood between them, and then cover the whole structure with hides. No doubt it was much simpler DWELLINGS 335 to twist together overhanging branches or brushwood into a roof, as, according to Tacitus, did the Finnish hunter-tribes, and as is the custom of the Hottentots and Bushmen to-day. ^schylus makes the Titan Prometheus boast that it was he who first taught men to construct brick and wooden buildings, before which they had dwelt like ants beneath the earth. There are clear indications that man dwelt in such wretched and bestial habitations buried in the earth, at any rate in prehistoric times. In Armenia, Xenophon found a race of men who in- habited underground dwellings, having narrow entrances like a well, though spacious underneath. Tacitus says the Germans, besides their mud huts, dug pits for dwelling in, covering the openings with manure ; they used them also as a refuge in winter, and as a storehouse for fruits. Virgil, too, sings of the Northern Europeans, " the Scythians live quiet lives deep in the earth in hollow pits". The description which Vitruvius gives of a similar dwelling in Phrygia shows that these pits, which were partly or entirely beneath the soil, and had more or less complete earthen walls, also possessed a roof. He states that over the entrance was a rounded dome made of stakes tied together, and covered with straw or rushes upon which earth was thrown. Similar, almost circular, pit-dwellings dating from the earlier Stone Age have been found in mid- and North Europe in considerable numbers ; inside them have been discovered numerous fire-places, crockery, and stone and bone tools. In addition to these roofed pit-dwellings, mud-walled huts were built, even in the early Stone Age. They were square with four upright corner posts, and horizontal beams between them. The roof was pointed, and the walls double, consisting of basket- work coated inside and out with mud, the space between being filled with a mixture of mud and straw. Schlitz has discovered an entire village of the Stone Age at Grossgartach, consisting of about ninety similar houses, with stables attached, together with a whole catalogue of household utensils. Representations of similar houses, some round and some square, from the Bronze, Hallstatt and La Tene periods, have been preserved for us in the baked clay house-urns (Fig. 162). Similar houses belong- ing to the German races are to be seen on the triumphal 336 THE HUMAN SPECIES column of Marcus Aurelius ; it must be remembered, however, that these probably represent rough, temporary dwellings, as the Germans of that time understood how to construct log houses. The use of posts, basket-work and mud for constructing substantial walls to dwelling-houses is a discovery which was known to prehistoric men of all eras ; but there is also an animal, namely, the beaver, which had learnt how to build in this manner long before him. This animal, which combines the work of a carpenter and a mason, can not only build strong dams with the logs and boughs which it has bitten off, mixed with mud which it col- lects and smears over them, but can erect its oven-like forts to which it betakes itself at high water to consume in peace the provisions which it has stored there. Man, too, so early as the Stone Age, found it con- venient in certain localities in Europe to take up his abode on the water. Thus in 1854 the first pile-built FIG. 162. House-urn from Alba Longa. village was discovered in the Hallstatt period. (Homes.) Lake of Zurich, and since then numerous other examples have been found in the neigh- bouring lakes. The strangest hypotheses have been brought forward as to the motives which induced man to choose such a site for his dwellings. The most natural and reasonable view is that man was compelled to make his dwelling-place in the water to secure himself against the attacks of animals or of other men. This is the object of the pile-built houses of North-West and South America, the Indian Archipelago, Melanesia and Africa. It must be supposed that the dwellers in the pile-built lake houses had formerly constructed similar buildings on land. The driving of the upright piles of oak, beech, birch and pine into the lake bottom was, however, a much more difficult NAVIGATION 337 matter than merely fixing them into dry ground. They suc- ceeded, however, in completing their arduous task with simple wooden and stone tools, joined their upright poles by means of crossbeams ; and on the platform thus formed they built their round or square huts with walls and floors of basket-work and mud, joining their lacustrine settlements with the dry land by means of easily moved wooden bridges. The terramara, a contrivance of the Bronze Age, consists of a pile-built village on dry land surrounded by a wall, examples of which are found in Upper Italy, Hungary and Bohemia. The best explanation is that of Homes, who thinks that the object was to protect the storehouses and sleeping-rooms from beasts of prey, troublesome domestic animals, noxious vermin, floods, etc., by raising them above the level of the ground. They are comparable to the houses of many South African and Papuan villages, which are raised on piles, the only difference being that the latter are never surrounded by a wall. Navigation. — All races who live on the shores of rivers or lakes are known to be proficient swimmers. It may therefore be assumed that the inhabitants of the pile-villages chose their lake dwellings owing to their familiarity with the water. But in order to sink their piles and to command the water, they must have had the means of travelling over it. We may understand easily how man first came to think of conveying himself in and steering a floating boat, when we consider how often he must have chanced to see broken trunks of trees floating in the water. If he swung himself on to one of them, he would discover that the trunk would bear him, and if he took a wooden pole in his hand he would find that with it he could steer in any direction he desired. This would lead to a new idea, namely, to bind together a number of trunks, and so to construct a raft which should be steerable and carry more than one person. Meanwhile, others would have discovered that the hides of animals when inflated (Fig. 163) were able to support considerable weights when placed in water. A stage made of longitudinal and cross beams fastened to four inflated hides, provided them with a ship able to brave all the billows ; this could be steered either by means of a rudder attached 22 333 THE HUMAN SPECIES to the stage, or by means of a man who swam behind and pushed the boat onwards, as is still the ancient custom in use on the Albanian lakes. Others again may have discovered that the bark of a strong tree removed en masse, fastened together fore and aft, and fitted with cross pieces floated capit- ally in water, and could carry at least one man, although great care was required to maintain equilibrium. Thus the first canoe was built. Under all circumstances, however, the solid tree-trunk must have inspired the most confidence, especially when hollowed out both in order to reduce its weight and to provide places for the rowers and for various appliances used on fishing and hunting expeditions. The hollowing out was probably accomplished by means of flint axes, the holes being further en- larged by burning with fire and then scraped out with sharp stones and shells. Neolithic canoes, two to five metres long, formed from tree-trunks, have been dug up at Robenhausen, Glasgow, and St. Valery (Somme) (Fig. 164). Such craft have long remained in the service of man, for even to-day in the Bavarian and Aus- trian lakes the fishermen and boatmen use the old solid tree- stems instead of boats put together by the art of the carpenter. The rudder consisted at first of a wooden paddle, widened at one end, and was used either standing or sitting ; it naturally permitted of very little actual steering. Sails were first used later on, when men had learnt to build larger canoes, or ships put together with planks, and caulked, and furnished at times with keels. And with this was combined the use of a movable rudder, attached to the stern of the ship. In such vessels man could navigate not only rivers and lakes, but also the sea itself, by cautious voyages along the coast, till at length, by additions to his invention, he could attempt further sea voyages, and so FIG. 163. Inflated goat's hide for a boat. (Corr. Bl.f, Anthr., 1904.) 339 become not only lord of the earth, but of the ocean also. Homes says of the ship that it is in the fullest sense both a weapon and a tool ; the most valuable instrument ever pre- sented to man's hand, and the key which has unlocked for him all the regions of the world. By this discovery man surpassed all the animals, and first established his right to be considered lord of the world, inasmuch as it made it possible for him to convey animals and plants to countries into which they had never come before. Training of Domestic Animals. — Although we may regard navigation as a characteristic attainment of man, we cannot apply the same terms to the training of domestic animals, as there is one animal which also pos- sesses domestic animals, and makes use of their products. This is the ant. Like all hymen- optera the ant is remarkably fond of the sweet juice secreted by aphides ; they do not only visit the scattered colonies of aphides in their settle- ments in different plants, but for the sake of convenience, seize the defenceless creatures and carry them off to the ant-hills where they can attach them to the underground roots of grasses. This is done in order to " milk " them, which is done by stroking the hind part of the abdomen till the sweet juice is excreted. At other times the ants allow the aphides to remain quietly on the plants they have selected for themselves, and then construct a covered way from the ant-hill to the colony of aphides, by which they can approach them unseen. 22 * 340 THE HUMAN SPECIES An aphide with a particularly long proboscis (Lachnus longirostris) attaches itself to the young shoots of trees in the interior of which the tree ants (Lasius fuliginosus and Lasius brunneus) make their galleries, by which they can reach their cattle, the aphides. Where no aphides exist, as in the tropics,, certain small sorts of locusts take their place, and are milked in the same way by the ants. There are still considerable differences between the various authorities as to the time when men first began to domesticate animals. Woldrich and Piette, for instance, consider that domestic animals were kept even in antediluvian times, and that the men of that period, whom we know only as fishers and hunters, had already tamed the reindeer and kept him in herds, with the help of the two antediluvian dogs (Canis Mickii Woldr. and Canis intermedius Woldr.).1 Woldrich bases his hypothesis on the fact that the reindeer bones found in the cave of Gudenus in South Austria belong to a small species. There is, however, no proof that this small species were tamer for differences in size exist in many of the wild deer. Against the view that the antediluvian reindeer were tamed is the fact that in the reindeer strata entire skeletons are seldom, or never, found. This shows that the palaeolithic man hunted the reindeer, and scattered them from place to place. Woldrich also maintains the possibility of the ox and horse having been tamed and domesticated, as well as the reindeer and dog. As far as the ox is concerned, there are no traces of this. Nor is it possible to suppose that the horse was tamed, unless we imagine that foals, taken after the mares had been killed and brought into human settlements, were entirely reared in the companionship of the human children. Band- like streaks have been found on the foreheads of many of the wild horses in prehistoric pictures, which have been taken for some sort of bridle. But all this stands on the very slightest foundation, as these animals which can only have been kept for pleasure, as is the case among all savage races, are certainly not indoor pets. It is only the transitional period between the two Stone Ages that provides any sure indications of a commence- ment, and it was the dog that the hunter and fisherman of 1 For dog ancestry, vide Flower and Lydekker's Mammals. PSYCHOLOGY the kitchen-middens (" Kjokenmoddingen ") chose to be his companion in the home. There is nothing remarkable in this occurrence if the habits of the half-wild dog are con- sidered— how he fawns on man and follows at his heel, half- shyness and half- assurance. We must conclude then that in early neolithic times the dog obtruded himself on man, and was accepted as soon as the latter discovered his utility in putting up and hunting wild animals. Besides the dog (Fig. 165), whom man has ever since regarded as a trusty friend, other domestic animals have been found in the deposits both on land and below the water. FIG. 165 Skull of hound. (Kobennausen.) Especially important sources of knowledge are the very definite remains of domestic animals recovered by Riitimeyer and Studer from the Swiss pile- FIG. 166. Skull of Bostaurus, var. primigenius. dwellings. The remains of two sorts of oxen, the larger primaeval ox (Bos Primigenius) and the smaller bog ox (Bos 342 THE HUMAN SPECIES Brachyceros) (Fig. 166). The bog swine (Figs. 167 and 168), apparently derived from the European wild boar, a goat, and a goat-like sheep, have also been found (Fig. 169). The horse, so frequently found in the first Stone Age in the neolithic period, is not found till the time of the pile-dwellings, and does not rank as a domestic animal till the Bronze Age is reached. In the same way the ass, the cat and domestic birds (the goose, duck, hen and pigeon) were not present during the earliest times in Europe. They were all later additions from the South and South-East. FIG. 167. Skull of a bog swine from Lattringen. FIG. 168. Mandible of bog sxvine from pile-buildings at Schaffis. Fields and Gardens. — The food of man has never con- sisted of meat alone, for his dietary also comprised the edible types of vegetables. In the early Stone Age he picked berries, shook down the wild fruits, gathered mushrooms and dug up roots. No traces, however, remain of all this activity ; it is only in the beginning of the second Stone Age that we come across distinct evidence of vegetable food, without, however, being able to say clearly whether it was derived from wild plants or from those cultivated by man. In the upper strata of the cave at Mas d'Azil, in Southern France, which clearly show the beginnings of neolithic civilisation with FIELDS AND GARDENS 343 its polished stone tools, are found not only broken stones of plums and cherries (which Piette considers were cultivated), but also the earliest specimens of grains of corn, of which no traces have ever been found of an earlier date. This shows that man must have had at this time settled abodes, as other- wise it is impossible to suppose that he could have cultivated fields or gardens. The tendency to a fixed habitation must have become stronger in each successive period, for, from the dwellings on land and water which have been explored, there are unmistakable signs of considerable neolithic husbandry, especially from the pile-dwellings, though like evidences can FIG. 169. Goat-like sheep. (Graubiinden.) be found in the huts on land. Heer, the botanist, has accur- ately classified the remains of household food-stuffs which have been found in the pile-dwellings. Among field crops he found ordinary wheat, and six- and two-rowed barley and millet (Fig. 170). Among fruits, two kinds of apples (a wild apple and a cultivated one), pears, cherries and plums ; and among plants used for spinning, flax. Besides these were grape-stones and poppy seeds. Other field crops, such as oats and rye, were only cultivated later by Europe 3 n races ; even the sorts named above were probably introduced into Europe by newcomers during the neolithic period. The men of this period had no metal tools or instruments 344 THE HUMAN SPECIES for tilling their fields and gardens. A pointed and hardened pole was all that served to break up the earth. More useful was the pole with a hook, from which later the primitive hooked plough was evolved ; or a pole to which a stag's horn, or a stone, had been fastened, of which many examples have been found. And when the fruits of the earth had been gathered in, they could either be eaten in the form of roasted grain, or they might be ground, by means of a sandstone grinder, either on a flat stone or on one with a trough cut in it. The ground grains would then be made into a paste with water, and baked to make a sort of loaf. The transition from the nomadic life of the hunter to the settled state of the agriculturist is the most remarkable epoch FIG. 171. Bronze sickle from Dachingen FIG. 170. Cereals of the pile- (Wurtemburg). (Swabian Explora- builders. tion, IV.) in the history of mankind. This step alone made the subse- quent development of human civilisation possible. But as \vith the keeping of domestic animals, so it is in the case of agri- culture. Man has no absolute monopoly, for the same remark- able little hymenoptera which employ aphides as cows, are also clever enough to plant certain grass seeds which are useful to themselves. An agricultural ant (Aphaenogaster) lives in a kind of cemented town, and takes certain measures accord- ing to the time of year. Within a smoothly laid yard they suffer nothing but a. single kind of grass to grow, which bears a sort of grain. These grains are removed, carefully hoarded, and yield a rich crop of small, hard, white seeds. When ripe they are harvested, carried into the corn-loft by the workers SALT 345 and freed fro'm chaff, which is thrown outside the house ; all these procedures differ but little from those adopted by man. Salt and how it was obtained. — According to the teaching of physiology a definite supply of mineral salts is very necessary for the maintenance of the human and animal tissues. The nutrient salts (sodium, potassium and calcium in combination with chlorine and phosphoric acid), which are lost in the urine and partly also in the faeces, have to be replaced by fresh supplies, or else the animal or man will die. This supply is ordinarily provided by the usual articles of diet, among which milk is especially important. There are, indeed, savage races who have no longing for special supplies of salt (sodium chloride) beyond that which is contained in the diet. Civilised man, however, finds salt indispensable, and many races obtain it from great distances by barter. There are also many animals (beasts of prey) which have no need of salt, whereas others (such. as the rumi- nants) take ener- getic measures to satisfy their need for salt ^IG° Z72° Handmill from South Sweden. We have no means of knowing whether palaeolithic man took salt with his food, or if so, how he obtained it. It is prob- able that his meat diet provided him with sufficient salt; it is still more probable that he had learned that ashes contain salt, by cooking his meat in hot ashes ; or that he obtained the salt which separated out from the pools near the sea- coast. When once the use of salt was fully established, it became a source of activity which at once raised savage man far above the animal kingdom by which he was surrounded. In all probability we may assume that the use of salt as a condiment belongs to the much more highly developed civilisa- tion of the neolithic period, when agriculture and stock-raising flourished ; moreover, in cases where there was no salt well in the vicinity, we may further assume that it was obtained from 346 THE HUMAN SPECIES the Southern and Western races, with whom we know, from the contents of their settlements, they were in close commercial relationship. The discoveries relating to earlier times have shown that in the following Metal Age (i.e., the Hallstatt period) the ob- taining and bartering of salt was an important industry. As at the present time, the salt was either excavated by miners, as in the celebrated Salzberg on the Lake of Hallstatt, or it was obtained by evaporating brine over a fire, as in the valley of the Seille, and in a region of mid-Europe which extends from Bohemia over South-West Germany as far as Alsace, Burgundy and the Franche-Conte. Near many of these brine wells hearths and clay supports have been found, over which the brine overflowed when boiling, and then evaporating on the hot brickwork left crystals of salt which can now be scraped or knocked off. Seeing that at the present time most bitter wars have been fought out between the desert tribes of the Soudan for the possession of the salt deposits on the road from Fezzan through Murzuk, we can easily imagine that similar sanguinary battles were waged over the prehistoric salt wells and salt mines. Sense of Beauty and Love of Ornament. — Neither of these can be absolutely predicated of animals, as is sometimes done very illogically. The structure of the visual organs of animals makes it self-evident, according to Schleich, that they possess the power of appreciating and distinguishing colours. All animal types in which, owing to sexual selection, the males are either gorgeously coloured from the beginning, or else don a beautiful marriage garment during the breeding season, must have a de- finite sense of colour and of beauty ; otherwise this sexual pheno- menon is inexplicable. One need but look at peacocks and turkeys, and the rich colouring of the male butterflies, to see how they display their adornments, or to read in the accounts of travellers of the colonies of male birds of paradise which plume themselves on the branches of the trees glittering in all the colours of the rainbow. What other object can they have than to excite the admiration of the female ? The desire to be of a pleasing appearance is therefore not peculiar to man, but is shared by other animals also. The endeavour to ornament ADORNMENTS 347 the body by means of extraneous objects is also found among animals. The male bower bird, who builds a bower for himself and for the hen he wishes to attract, decorated with variegated stones, shells and feathers, will take a pretty feather or brightly coloured leaf in his beak and dance in and out of his arbour with it (Fig. 173). This, indeed, is but a solitary instance, and is of slight im- portance compared to the universal desire for ornament which man has displayed from the earliest times. But I cannot agree with Waitz that the endeavour to decorate his body in some FIG. 173. The spotted bower bird (Chlamydera moculata). (Brehm.) way constitutes a specific difference between man and other animals. Although, as we have seen, no absolute difference exists, the relative difference is extraordinarily great, seeing how manifold are the ways in which man's desire for ornament manifests itself. In the first place, the coloured earths which are found in nearly all palaeolithic settlements probably served for painting and ornamenting the body, possibly also with the addition of tattooing, for which the small flint knives of the Madeleine period may have been used. Then there were necklaces of teeth, small stones, shells of snails or mussels (Fig. 174), 348 THE HUMAN SPECIES minerals, corals, ammonites, shark's teeth, and numerous other glittering objects, which the wandering hunter took to decorate himself withal. In the neolithic period necklaces were made of beautifully polished shells, often brought from distant lakes, and armlets of large polished mussel shells. All these ornaments were buried with the dead in their graves. Even as early as in the transitional period, between palaeolithic and neolithic times (Mas d'Azil, Mentone), skele- tons coloured red have been unearthed ; it is, however, uncertain whether the corpse was strewn with the coloured powder, or whether the bones were tinted after the flesh had been removed. Personal ornaments became much more varied when man learnt to employ the metals. Bronze especially allowed of great variety of working, and satisfied all artistic requirements ; indeed, the perfect finish of the bronze orna- ments excites our admiration even now (Fig. 175). Should we be right, it may be asked, in constructing a picture of the prehistoric in- habitants of Europe from our knowledge of how modern savage races adorn their persons ? I think this question may be answered by an unqualified affirmative. To-day savages decorate themselves with ornamental feathers, necklaces, armlets and carvings, and paint themselves in the most diverse manner. FIG. 174. Orna- ,T7 , . , . , . , .. „ ments made of Were the nations who paint their bodies, said Humboldt, " observed with the same care as those that wear clothes, the same diversity of design, and the same unending variety of fashion would be found in the manner of painting which has been observed in the composition of clothes." We may there- fore also suppose that with regard to the dressing of the hair (and also perhaps of the beard), the same infinite variety teeth and shells from La Ma- deleine. (Hor- nes.) PAINTING 349 obtained among prehistoric people as is seen among the savage races of to-day. The Art of Painting. Here again we find a region in which man stands alone among the entire series of animal life. No animal is able to reproduce his observations or ideas in a pictorial form. This man can do ; not on account of his hands, as apes also possess hands, but on account of his human soul. That artistic aspirations are inborn in all human beings, is seen by a glance at the attempts made by the children of all nations. They make playful attempts at scribbling pictures of trees, animals and men of the quaintest description, and when they can get hold of mud, they use its plastic properties to con- struct models of new forms suggested by their active imaginations. As this desire for art exists in all children, and in all savage races, so in the earliest times of human existence we meet with marked artistic activity. We might indeed almost imagine that this phenomenon was physiological in nature, and that art was as necessary to man as salt. To return once more to the children, we may learn from them that in many ways, both bodily and spiritual, the childhood of European and other civilisations reflects the natural life of the human race (Klaatsch). Palaeolithic art regarded with not unnatural wonder the entire natural world, as seen on Western European soil. It did not concern itself with decorative patterns, but produced free- hand drawings of animals (mammals, birds, reptiles and fishes), less frequently men, and least frequently of all plants. It attained within its own province a higher level than does FIG. 175. Bronze ornament of the Hallstatt period, -| natural size. (Homes.) 35° THE HUMAN SPECIES the art of the savage hunter-tribes of the present day — the Australians, the Bushmen, and the Eskimos. These free- hand drawings, however, are not found in all the settlements of the reindeer hunters, but chiefly in France. They also occur in Thayringen and Mahren. At first it would seem remarkable that in the oldest settlements of the mammoth period plastic arts predominated (Fig. 176). It may, however, be assumed with much probability that it was the convenient curve of a piece of bone, horn or ivory which enabled the artist to execute his small portable statuettes. It must have been still more alluring to the palaeolithic hunter to carve out of wood the animal which interested him ; we cannot prove, however, that this occurred, as the material must long since have perished. A higher level in art, first attained by the hunters of the reindeer period proper, is characterised by life-like carving on bone, horn and pieces of chalk (Fig. 177). These are not often found in the camping places of the hunter-tribes, but are most frequent in the cave-dwellings which they inhabited later on ; the idea, therefore, that the higher artistic development was oc- casioned by the greater permanency of the dwelling-place is not without some foundation. This higher development of art is especially noticeable at the time when the wild horse was mainly hunted in France ; and to this period belong the beautiful reliefs of horses cut on reindeer horn, on which also are small carved patterns. The highest grade of palaeolithic art was attained by the employment of colour. The river flints in the grotto of Mas d'Azil, painted with the most varied figures in red paint, attracted very general attention as being the earliest specimens of composition in colour made by man. But the wonder grew still greater when the paintings of animals of great size were FIG. 176. Back view of fe- male torso in ivory from Brassempouy. (Palaeo- lithic, ^ natural size.) ARTS 351 found in the mountain caverns of Northern Spain, and in the French district of Vezeretal. In this case the hunter-artist was not content merely to scratch on the walls of the cave an out- line of the animals he hunted (bisons, mammoths, horses, antelopes, reindeer and ibex), but he added also shading and colour, using the pieces of yellow ochre and black manganese oxide found in the cave. How such animated pictures, so true to nature, could have been completed in the darkness of the cave, or lighted only by a torch, remains an insoluble puzzle. These cave paintings of Northern Spain and Southern France have something of the freedom of the palaeolithic art. With- out conscious effort they spring solely and entirely from the FIG. 177. So-called sceptres with figures of animals. (Homes.) artist's enjoyment of form and colour. Together with the outline drawings on reindeer, horn and chalk plaques, which must be regarded as purely imaginary creations, they deserve the first place in the early history of art. Certain drawings and carvings may be given the second, which serve as a decoration to some useful article, such as a spear-head, or the so-called sceptres. These works of art also attained a position which was never reached in the next or neolithic period. The characteristic of this period is the appearance of conventional patterns. The palaeolithic hunter-artists did not disdain to fill in their outline drawings here and there with geometrical ornament by way of framing, or 'filling them in with squares or zig-zags ; we even possess carvings which are 352 THE HUMAN SPECIES decorated with purely conventional spirals, rings or curves ; ornamentation of this sort is, however, to be sought in its most characteristic form in the neolithic period. The cause of this difference in the palaeolithic and neolithic ornament is not difficult to discover. As the neolithic people appear to repre- sent quite a new race, with their tendency to settled abodes, their agriculture and their stock-raising, so their art seems to develop along different lines and to arise from a different source. Palaeolithic art took its models from the animal world around it ; it was a masculine art carried out by hunters. The neolithic, on the other hand, was a feminine art. The women who made the pottery and designed the ornaments for it took their ideas from the patterns of their weaving and plaiting. It is immaterial whether basket-work especially gave rise to the introduction of geometri- cal patterns. This much, how- ever, may be gathered from the consideration of the savage races of tne present day, namely, that some form of industry must al- ways have preceded ornamenta- tion. The African Bushmen and the Veddahs, who possess many industries, show no trace of ornament. But in the neo- lithic period, and for long after, geometrical ornament, with its rhythmic repetition of design, its simplicity, and its power of adapting itself easily to any flat surface, established its place in the history of the origins of art. Strictly speaking, however, it ceased to be a pure art, but must be considered as a craft, as we can see that the ornament was no longer drawn by hand but was generally stamped with a die. The circumstance that the deeper lines were filled in with a white paste while the clay was wet, in order to heighten the colour effect, does not elevate this neolithic craft to the status of art (Figs. 158 and FIG. 178. Bisons. Frescoes from the wall of the grotto Font deGaume (Dordogne.) (Homes.) ARTS 353 159); the comparatively high finish shown on the pottery of Butmir (Serajewo) only places in more glaring contrast the unsightly plumpness of the only carved idol found belonging to the end of the neolithic period. As we have seen, the employment of copper and bronze in the metallic period gave rise to an important era in the history of human civilisation. But the general advance in civilisation was not at first accompanied by a corresponding advance in art, indeed the latter for a long period remained under the influence of its neolithic predecessor. The oldest metal imple- ments were merely unadorned copies of those of the Stone Age ; subsequently, first under the influence of the people of the south and south-west, and later on spontaneously, ornament appeared on manufactured objects, and acquired a character definitely denoting the Bronze Age. The ornamentation of pottery was thus entirely by way of linear designs with the exception of two localities, which developed independently a culture of their own in the Bronze Age. These were North Scandinavia with its highly finished bronze statuary, and the coasts and islands of the ^Egean Sea in the south, where a mar- vellous delicacy of execution both in drawing and sculpture was developed. The most beautiful examples have been unearthed at Hissarlik (Troy), Mycenae and Tiryns, and at the recent ex- cavations in Crete. They include not only carved objects in bronze, the noble metals, amber, marble and alabaster, but also the oldest painted vases partly decorated with geometrical orna- ments and partly with pictures of men and all kinds of animals. In the earliest Iron Age, which ushers us nearly into the domain of history, metal work is only prominent in contrast to works of art ; the latter, as far as the drawing of men or animals is concerned, is far inferior to Mycenaean art. On the other hand, high praise^ must be accorded to the women potters of the Hallstatt period, as they were evidently filled with the desire of imitating in their clay designs the workers'TfTbronze wKcTTiad preceded them. Their ornaments included small figures of men and animals, as did those of the last named. They also tried to make vessels in the shape of mammals and birds, and could not resist ornamenting the faces on their urns with earrings and necklaces of bronze. 23 354 THE HUMAN SPECIES A well-developed sense of colour is shown in the large ceremonial urns and platters taken from the barrows of south- west Germany. They have geometrical patterns deeply en- graved on the clay, and painted with various colours. In Greece, and the Greek colonies, the painting of their beautifully shaped vases soon began. These vases were turned on a wheel, and were much valued throughout antiquity ; even now they are the delight of all lovers of Art. It is not iron itself that has left its mark on the art of the early Iron Age. Still less can this be said of the later Iron Age (La Tene), which may be put at about B.C. 400. The Celts indeed, the diffusers of the La Tene civilisation, were masterly ironsmiths, who employed this valuable metal not only to manufacture arms and tools for the household and the field, but also for ornaments of every description. The output, however, was modest, unless we reckon the patterns engraved on the iron sword blades, the animals' heads on their chains, and the enamel inlaid work on the more deeply-cut engravings. The characteristic ornaments of this period are the triangle, the spiral, and especially the conventional flower pattern which are all rare in the previous periods. The Celts, however, em- ployed it extensively ; and even hundreds of years later it appears in the miniature paintings executed by the Irish monks. On the other hand, the pottery turned on the wheel was fault- lessly made though considered poor from the artistic point of view. The art of La Tene, which we know mainly from its relics, leads on into historic times — times in which Greek Art, the model for all subsequent ages, was fully developed, and in which that of Egypt was already waning. When we take a general survey of the prehistoric art of Europe, that of the palaeolithic hunters is the only one which strikes us as autochthonous. The subsequent periods can only be understood by duly considering the influence of the south and east, where even in the grey dawn of the world, races were established endowed with what we must regard as a most amazing genius for Art. Thence, from Egypt and from the coasts and islands of the ^Egsean Sea, from Asia Minor in the Mesopotamia!! " hinter- lands," flowed forth the European races in devious lines, stimu- MUSIC 355 lated by the all-important commercial instinct, till they reached the furthest north of Scandinavia. Even Greek art was in- fluenced in its beginnings by southern and south-eastern models, although later on this influence was entirely discarded and it established itself in its own brilliant individuality. Eventually indeed it inspired the art of the Mediterranean races, the Illy- rians, the Etruscans, and finally the Romans themselves. The same thing was repeated in the case of the Celtic art, which we knew as that of La Tene. For the Celts the place of entry for artistic influences was Massilia, but here streamed in not only the products of Greek art, but those also of the Egyptian from North Africa and of Phoenicia from Asia Minor. From these the Celts could take their examples and work them out in Celtic fashion, till their influence, in its turn, could stimulate the productiveness of the surrounding races, and extend even to the art of Scandinavia and Britain. Vocal and Instrumental Music. The power of artistic thought, and the power of expressing it in works of art is, as we have seen, an attribute of man alone ; this does not apply, however, to vocal and instru- mental music, for both of these can be produced by certain species of animals. The sounds made by mammals are produced usually by the vibrations of the vocal cords in expiration, and partly also in inspiration ; with the exception of the Hylobates agilis, and possibly other varieties of hylobates, and the singing house mouse, these sounds are mere noises and not musical. " A female hylobates," says Brehm,1 " utters a loud cry which is peculiar, and quite melodious. It can be per- fectly well represented in musical notation. It begins with E as a ground note, and then rises in semitones through a full octave, thus completing a chromatic scale. The ground note is heard throughout, and forms a kind of appoggiatura to each subsequent note. In the ascending scale the notes follow each other more and more slowly; in the descending scale they become quicker and end with extraordinary rapidity. The end is always a piercing shriek which is uttered with all 1 Brehm, loc. cit., i., p. 39. 23* 356 THE HUMAN SPECIES her power. The regularity, rapidity and certainty with which the animal screams out the scale is extremely remarkable. The ape herself appears to be very much excited by it, as every muscle is thrown into contraction, and her whole body is shaken by a shivering movement." This is in effect a true song, although it only consists in repeating the same scale over and over again. The song of the singing house mouse is quite different, and is often mistaken by the uninitiated for the squeaking of young mice in their nest. But it is really no mere squeaking noise, but a perfect song moving in accurate intervals, and produced by a full-grown mouse, as I was able to observe long ago in a singing mouse which I kept in captivity. Bamfield has explained the song of the house mouse in his home as an imitation of that of a canary in his kitchen, which is not so very improbable considering the well- known fondness of house mice for music. Other observers, however, besides myself, have noted that the house mouse will sing quite independently of hearing a canary. The only remarkable thing is that singing mice are so seldom heard, as it has been proved that they form no special class of mice, but are only of the ordinary variety found in houses. These two examples of singing mammals have no real con- nection with singing birds, and these differ from one another though comprised in allied orders. Their distinguishing mark is the possession of five or six pairs of muscles in the larynx which produce the characteristic sounds. At the same time all birds possessing this apparatus cannot be accurately classed as singing birds ; ravens and birds of paradise can only produce a kind of shriek. The remaining birds are more definitely song birds, finches, yello\v-hammers, tanagers, stilts, pipers, tomtits, tailor birds, thrushes, starlings and butcher birds. The very various songs of the birds may be classed in three groups according to their loudness, their beauty of tone and their richness. Those birds are said to warble whose voice is strong and sweet, and whose song always or generally con- sists of a sequence of notes such as the nightingale, the chaffinch, the canary, the wren and the black-cap ; those birds are simply said to sing when their notes flow forth without any regular sequence, mingled with softer twittering sounds, SINGING 357 such as the lark, the grey hedge-sparrow, the green-finch and the redbreast. Piping is the name given to singing which consists of clear fluty tones which may be expressed as notes and which well out in beautiful melodies like those of the blackbird, linnet and oriole. Many consider the song of the nightingale the most beautiful thing of which a bird is capable. When, however, we compare it with the glorious and ever- varying song of the field lark, and other varieties of lark, or when we listen to the song of the mocking bird, or the red- backed butcher bird, or the reed-warbler, we cannot hesitate to award the palm among all birds to these singers. In men also the love of song is inborn ; this is seen in the children of all nations, who can sing long before they can talk, and try to perform " songs without words " of their own com- position. The songs of the mountain folk consist of these lays without words, which they produce either alone, or accompanied by songs with words, through the actual joy of living. When we come to examine savage races, we find that there is no emotion of any importance, whether sad or pleasurable, to which they do not give expression in extempore song often accompanied by dancing. Herder and Wilhelm v. Humboldt called man a "singing animal". Ludwig Noire, the gifted pupil of Lazarus Grieger, the etymologist, described as peculiar to man " the song which arises from pure delight in his own existence, in which thought is wedded to beautiful sounds, and thus has contributed not a little to the development of language ". Darwin comes to the same conclusion from the biological point of view. As the males of most kinds of quadrumana have more highly developed vocal organs than the females, and since the hylobates (male and female) can produce a whole octave of musical notes, it is not improbable that the predecessors of the human race before being able to express their love in any kind of language, tried to excite each other's passions in musical tones and rhythms. In course of time men learnt by experience to increase the aesthetic value of their songs by attention to harmony and rhythm, until finally the laws governing these things were dis- covered by the appointed genius, and it was found that "aes- thetic satisfaction can only be obtained when, on the one hand, 358 THE HUMAN SPECIES harmonies and discords succeed each other, by the simultaneous production of several notes, and when, on the other hand, in the course of various musical productions, a definite accen- tuation of tone recurs at regular intervals of time (rhythm) " (Wundt). It may again be pointed out that instrumental music is no monopoly of the human race, as when the drum, tambourine and rattle were added to the musical instruments employed by man, the corresponding instruments used by animals could everywhere be seen and heard. Woodpeckers drum, tapping on a bough with a rapid succession of blows with the beak delivered with a swinging movement ; the North American woodcock (Tetrao umbellus) drums, beating his wings together across his back. The cockbird of the black West African weaver-bird glides with quivering wings through the air and so produces a rapid whirring noise like that of a child's rattle. Many male goatsuckers during the breeding season make a peculiar buzzing noise when flying through the air. Storks produce a clapping sound by shutting their bills ; peacocks and birds of paradise rustle the quills of their plumage ; the male lapwing combines vocal and instrumental music by first draw- ing in the air, and then in a moment blowing it out again, at the same time striking the end of his beak straight on to a stone, or tree-trunk. Becassines have a number of tail feathers specially arranged so that in their rapid flight through the air a remarkable whirring, humming, or even clattering sound is pro- duced ; the cock Chamaepetes unicolor in America, the Indian Florican (Sypheotides aurita), and a species of pipra have a similar mechanism in their wing feathers. Certain arthropods are keen musicians. The males of several kinds of Theridia (spiders) are able to make a kind of whirring noise. The buzzing of Diptera and Hymenoptera is not a mere involuntary result of the movements of the wings in flying, but a voluntary act, produced by squeezing the air out of the trachea. The death's head moth (Acherontia atropos) makes its shrill piping noise by rubbing its proboscis upon the strong ridges on the inner surfaces of its antennae. The dron- ing of chafers can be heard at a great distance and is mainly due to the rasp — a part of the body marked with paralell ridges, SINGING 359 which is scratched by the so-called " scraper," a neighbouring part which is furnished with a hard edge (Fig. 179). Some Hemiptera (bugs), such as Pirates stridulus and Reduvius personatus, produce a shrill sound by moving forward their thighs within the cavity of the prothorax. The male locust or cicada has this power still more developed, and was said by the ancients to "sing". According to Landois the sound is produced by the vibrations of the margins of the respi- ratory tubules ; Powell attributes it to the vibrations of a mem- brane which is put in motion by a special muscle. The male crickets and grasshoppers also chirp and squeak continuously. According to Darwin, there is a kind of locust on the river Amazon which produces so melodious a sound that the Indians keep it in little cages made of plaited willow. Although the musical instruments of the three sub- orders of the Orthoptera are so various, they are all remarkably simple in con- struction. In crickets a toothed ridge, or vein, on one wing-case is rubbed trans- versely with great rapidity against a smooth hard ridge on the upper surface of the opposite wing ; in locusts the left wing is the violin bow, lying across the FlG I?g Chafer (After right wing which is used as a violin ; there Landois.) r, the rasps. is a fine " nerve" with a saw-like edge on the under surface of the left wing which is drawn transversely over the " nerve " which rises from the upper surface of the right wing. The Acridides do their fiddling in a different way : generally speaking, the inner surface of the upper part of the thigh, which is furnished with little elastic teeth, acts as violin bow (Fig. 180), and they play either on the ridges attached to the wing cases, or on a ridge on the abdomen, the lower part of which is expanded so as to form a large bladder in order to increase its resonating powers. These examples, I think, show that there is no lack of musicians among animals ; I shall now proceed to give a short resume of what is known concerning prehistoric musical instru- ments and the beginnings of instrumental music. A complete history of musical instruments, or an account of the instru- 3<5° THE HUMAN SPECIES ments of the savage races of to-day, would require a large book to itself. According to Darwin, it must be generally assumed that singing is the basis or the source of man's instrumental music. I have considerable doubts, however, as to the correctness of this assumption, and believe it to be highly probable that the latter is quite independent of the former. As, in their games, our children, and the children of all nations, will produce a note by blowing down a reed, or by tapping a pot, a vessel or a board covering a hole, obtain further sounds owing to their resonance ; or as, when they pull on a stretched cord, they are surprised at the duration of the vibrations, so the prehistoric men arrived at the construction of instruments by dint of experi- ment in playing. Pipes made of the phalanges of the reindeer bored with a hole (Fig. 181), were found in the palaeolithic settlements in France and in the Swiss pictures. Lartet has described two flutes made from the bones and horn of reindeer which were found in palaeolithic caves in France. In the same way flutes could be made of the long bones of birds simply bored with holes in them, and like many flutes of elderwood or pieces of reed, may have rotted away in these caves. It may be assumed as very probable that such wind instruments were first made for children, and by children out of willow, or reeds, which are easily cut. Very likely this was first done by the neolithic dwellers in the lake villages where they were sur- rounded by reeds. We do not know whether the palaeolithic hunters blew upon horns taken from the bisons and bulls which they hunted, nor do we know whether they possessed wooden drums covered with hides like modern savage races ; if this was the case they must long since have decayed like the wooden pipes and flutes. We possess a single drum of clay (Fig. 182) FIG. 180. Hind leg of Stenobothrus pratorum. (After Landois.) r, the ridge by which the sound is produced. Below are the teeth of the ridge magnified. MUSICAL INSTRUMENTS 361 of the Neolithic Age, which is very similar to those of the savage tribes of Southern Asia and America. Balfour (The Natural History of the Musical Bow, Oxford, 1899) says tnat the first stringed instrument must have belonged to the same period as the clay drum, because the bow used in music was developed from the bow used for shooting, and the first example of the latter is found in neolithic settlements. Balfour distinguishes three stages of development :— (r) The bow used for shooting, which now among the Kaffirs, Mandingos, Damaras, etc., in South Africa is oc- casionally used as a musical instrument. FIG. 181. Pipe of reindeer bone. FIG. 182. Clay drum from Ebendort, near Magdeburg. (2) One-stringed bows solely made for musical purposes (Zulus, Niam-Niam, Bongos, Basutos, Mashonas). (3) As an addition the bow has a resonator, usually a hollow gourd, to improve the tone. This kind is the most widely distributed. The bow, according to Balfour, was the true prototype of stringed instruments in ancient Greece and Rome, in Northern and Central India and in Central Brazil. If we imagine this bow made rather more solidly and furnished with several strings of various thickness, we have a harp in its simplest form. 362 THE HUMAN SPECIES There is, however, another mode of origin for stringed instru- ments played on by the finger. If they did not wish to use a large gourd with strings stretched across it, it was but a step to employ the empty carapace of a tortoise for this purpose. The fact that a six-stringed "chrotta" has been found in the Alemannic cemetery at Oberflacht shows that the forefathers of the German people had attained to this kind of musical instrument. And it was also only a short step in advance to fill in the space between the branching horns of an ox, or antelope, with strings, and so to create the famous lyre. Prehistoric musical instruments are but so rarely found that any representa- tions of them either in statuettes, or in outline drawings, are of extreme value. There are two almost perfect marble figures belonging to the period of that civilisation which surrounded the ^Egean Sea which were found at Keros, near Amorgos. One represents a player on a double flute (Fig. 183), and the other, a sitting man with a round-shaped harp. On an urn from Oldenburg (Hallstatt period) small figures playing on stringed instruments near some large female figures may be seen rather crudely outlined. FIG. 183. Flute player of . . r , TT .. -11 u limestone from Keros, Also of the Hallstatt period but much better executed is the representation of an artist playing on a seven-stringed lyre on the bronze platter from the temple of Alphaeus at Olympia. All these indeed belong to a time when outside the boundaries of Europe the skilful races of Asia and Egypt had long been in possession of perfect musical instruments. Writing. Writing is the final point in man's monopoly of the in- tellectual world, and springs from an inborn desire for the power of recording thoughts, experiences and events. The need of such a record must have been felt by the near Amorgos, £ natu- ral size. (Homes.) WRITING 363 palaeolithic hunters, for in many utensils made of reindeer bones we find, besides the carving and outline drawings of animals, peculiar linear stripes and curves (Fig. 184) arranged in a de- finite way which must be considered to be either figures or marks to denote proprietorship. The remarkable drawings previously described on the flints of Mas d'Azil (Fig. 185), con- sisting of crosses, rings with dots in the middle, serpentine lines, ladders, tree-shaped signs, zig-zags, etc., were explained by their discoverer Piette as letters, while R. Andree thinks the flints were used for counters, and the marks painted on them denote the proprietor. This very probable view implies the existence of hierogly- phic characters, which, according to the opinion of all the authorities, was the first foundation of the art of writing in all parts of the world. Wundt has traced the process of the de- velopment of writing with great clearness and accuracy. Hiero- glyphics, or word-pictures, form naturally the universal starting FIG. 184. Rod with marks scratched on it, made of reindeer-horn. (Homes.) point ; this consists in copying the shape of an object, in order to represent it graphically. " As soon as speech became capable of expressing abstract ideas, writing had to, follow. From the hieroglyphics were developed sound-symbols, but every one of our letters shows traces of its hieroglyphic origin. Eventually the sound-symbols which had originally denoted one word developed into the alphabetical elements of speech, in order to keep pace with the extended powers of verbal expression." Hieroglyphics, which preceded writing proper, consisted either in imitations of natural objects and could thus be under- stood by all the nations of the world, or in symbols, certain simplified outlines of natural objects which could only be understood by the learned. At the present day the Eskimos and Tsuktseu with their signs scratched on wood or ivory, the prairie Indians with their drawings on hides, the inhabitants of Central America with their paintings on paper made from the 364 THE HUMAN SPECIES Agave americana, and the Bushmen with their inscriptions on rocks and slates, do not bring us much beyond the region of hieroglyphics. Even now the prairie Indians paint their so- called winter annals on the inner surface of hides. In all these cases the figures and their meanings are easy to understand, and the same may be said of the celebrated Walam Olum, the painted board of the Leni-Lenape, on which the entire story of the wanderings of this tribe is represented in plain outlined characters. On the other hand, the rock inscriptions in South America, and in certain South Sea Islands, are not even yet clearly explained, any more than the prehistoric hieroglyphic symbols from the south or north. The signs employed by the tribes from the south and south-west are often derived from objects in daily use, such as the spinning-wheel (crosses, FIG. 185. Flints, painted in red, from Mas d'Azil. (Homes.) hooked crosses, or crosses with handles), and apparently have a tropological character. The Phoenician T cross, and the Egyptian cross with a handle to it, are known to be abbrevia- tions, standing for the human form, and the volute and double volute as symbols of the female breast. The hieroglyphics on the carved stones at Mycenae, Tiryns, Menidi, Vaphio and Corinth are very difficult to interpret, possibly they are figures put together from several animals. Homes may very probably be right in supposing that they are hieroglyphic words and sentences in which the chief of some small clan and his relatives gave nai've expression to their views on the mightiness of their totem or tutelary deity as compared with foreign demons. The northern hieroglyphics, dating from the end of the WRITING 365 neolithic and i the succeeding Bronze Age, arejalso very difficult to interpret ; so too are the rough irregular figures cut on flat stones, and the " Dol- men" stones from the North of France, England, Ireland and South Scandinavia which are sym- bolically decorated with shells, crooks, yokes, combs, hatchets, axes and bucklers. Then there are the inscriptions on the rocks at Bohuslan (Sweden), the ornamented stone plaques in the civic monument in Schonen, and the small stone basins found in Switzerland and other countries, all of which are hard to decipher. We must suppose that much of these hiero- glyphics deal with the exploits of various races and their chieftains, of voyages and raids, and ideas as to the rule of the gods ; but we have nothing on which to base an accurate interpre- tation. To pass on to the hieroglyphics of the ancients, those of the Egyptians must by rights be first mentioned (Fig. 186). Flinders Petrie, however, thinks that the earliest beginnings of the Egyp- tian hieroglyphics are to be found on a neolithic vase discovered by himself, which is painted with a mixture of geometrical figures and convention- ally drawn natural objects (plants). By-and-by, in the course of the next thousand years, the sacred writings were put together; 500 signs were used, more or less true pictures of men, animals and objects of all sorts, and their values and meaning may be classified under four head- ings, namely, alphabetical signs, signs representing syllables, signs representing words, and deter- minatives. These are not all engraved on stone, or metal, but are written, or rather painted, with reed pens on papyrus leaves. Passing over the hieroglyphics of the Mesopo- tamians, the ancient Persians and the Armenians, which are thought to be the historical antecedents FIG. 186. One side of the hieroglyphics inscribed on the obelisk at Luxor. (Kar- peles.) ;66 THE HUMAN SPECIES of the later cuneiform writing, we come to the ancient Cretan hieroglyphs which are of quite exceptional importance, owing to the fact that they are the parents of not only the Aryan but also of the Semitic characters. They are very similar to the hieroglyphs of the Heths and the peoples of Asia Minor, and to a certain extent to those of the Egyptians, and were evolved in the nineteenth century B.C. In the Egyptian hieroglyphics many parts of the human body are used as signs, as also are various plants and animals, weapons and tools, gates and walls, half-moons and stones and numerous geometrical figures. FIG. 187. Example of a Chinese inscription of Yu. (Karpeles.) The Chinese, Japanese and Korean characters (Fig. 187) are derived from a similar hieroglyphic origin ; but whereas these nations have exchanged their hieroglyphics for letters proper a thousand years ago, the Spanish conquerors found the natives of Central America still using their ancient and obscure hieroglyphics, in which both realistic pictures and conventional signs were used to express ideas. In the far East the Chinese exchanged their hieroglyphs for letters proper, turning the original pictures and symbols into the well-known characters which are arranged from above downwards one below the other. They are painted on paper WRITING 367 with a pencil and Indian ink, and were later on adopted in a modified form by the Japanese. The Mesopotamians, the ancient Persians and the Armenians changed their early hiero- glyphs into cuneiform characters (Fig. 188), which consist of straight lines drawn at one end to a point, (and arranged either horizontally with the broader end to the left or else vertically with the broader end at the top. Exceptionally they are oblique, with the broader end either above or below. Thus by means of repeating the signs, placing them either next to or over one another and crossing them, a number of complicated figures were obtained. They were engraved on stone with wedge- shaped chisels, or moulded in wet clay «' * A * o , - with wedge - shaped sticks. On European soil it was in Crete that the inhabitants of the vEgean Islands first changed the hieroglyphs which had been in use for hundreds of years into a regular sys- tem of writing, which differed from that of the Cypriots in that FIG. 188. Example of the arrangement of the lines in an ancient Babylonian inscription. (Karpeles.) each sign stood for a sound only, and not for a syllable. The main foundation for a practical system of writing was, however, laid by the Phoenicians, who formulated an alphabet of twenty-two char- acters, containing consonants and semi-consonants and written from right to left. From this was developed the early Semitic writing, and this again was the mother of the Greek, in which the alphabet was increased from twenty-two to twenty-six characters. The Italian peoples (and perhaps even earlier the Etruscans) obtained their alphabet in an altered form from the Greeks, and the Celts derived theirs partly from the Greeks and partly 368 THE HUMAN SPECIES from the Italians. Among the old German peoples the priests, in order to discover the will of the gods, threw little beechwood darts, each of which carried a " rune " — that is, a sign or picture engraved on it — as a symbol of a god or of the thing whose name the rune bore. These sacred signs became changed later on under the influence of the Romans, till they became what we now know as " characters V Ulfila, in the fourth century, constructed the Gothic alphabet from these meta- morphosed runes. The word " Kerbholz," meaning a tally, or literally, a notched stick, still used in Germany, shows how the old Ger- mans relied on a piece of wood with notches cut in it, both as an aid to the memory, and also in order to show how much was due to the creditor in commercial transactions. A tally about the size of one's finger is still used by miners; the master scratches his name on it, and it is used to summon certain persons. Among other peoples, however, and at other times, another method was in vogue for assisting the memory for figures and such-like things, namely, writing by knots. A short history of this practice has appeared, written by Martin Beck. The system of writing by knots is primaeval in China; as far back as 3500 B.C. important historical facts were recorded by means of long knotted cords, in which not only were the length, form and colour of importance, but also the kind and number of the knots had special meanings. The system fell into disuse in 3000 B.C. when the Emperor Tchang- Kai invented hieroglyphics. In colour, in shape, and in the way the colours are mixed the Quippus, or knotted cords of the Peruvians, when they were discovered by the conquering Spaniards, were remarkably similar to these. Not only was all acquired knowledge recorded in the Quippus and only understood by the higher classes, but also the whole national budget, the revenue and expenditure, the census, the occurrence of wars, and the government annals were set down. More- over, certain specially skilled officials were appointed to keep and interpret the records as occasion demanded. For a single 1 The German words are similar, Buchenstab, means a beechwood rod ; Bnchstab, a letter or character. PSYCHOLOGY 369 coloured cord, or the number and character of the knots, did not denote (as in hieroglyphs) an idea, a number or an event, but they were only a means of refreshing the memory as to these things. In the same way the knotted strings of the South Sea Islanders (Figs. 189, 190) are genealogical registers and his- torical records, which in earlier times could only be recounted, or sung, by a few individuals, and only when the strings with FIG. 189. Knotted cord from Hepatone, Tahuata, Marquesas Islands. (After v. d. Steinen.) their knots were actually in their hands and before their eyes. Finally, to take another glance at America, the North American Indians had the same mnemonic device in their strings of mussel shells and their wampum girdles, as had the Peruvians with their Quippus. The girdle of a distinguished person was artfully constructed of animal tendon, with knots, separated by strings of pearls and shells presented by the envoys on important occasions, such as the making of a treaty 24 37° THE HUMAN SPECIES of peace. It had all the significance of a state document, for each colour, each knot, and each shell had its own particular meaning. It was the duty of the tribal chief to preserve the wampum girdle in the treasury of the tribe, and to teach the growing youths from time to time the history of their tribe by showing them the girdle ; its peculiar arrangement was thus impressed on their minds and served to refresh their memory. FIG. 190. Knotted cord from Hepatone, Tahuata, Marquesas Islands. (After v. d. Steinen.) Psychological Retrospect and Forecast. We who live in the twentieth century with our rapidly printed books and newspapers may well smile at the naive inadequacy of these knotted cords and hieroglyphs. [t is only right, however, to remember that these things are but the prelude to a higher civilisation, just as the freehand draw- ings of the palaeolithic hunter-artists and the geometrical ornament of the neolithic period formed the foundation of PSYCHOLOGY 371 all human art. We may observe the same advance from lower to higher things in all regions in which man's special attributes are exercised. The races from Which civilised nations have sprung have gradually developed their origin- ally meagre and inadequate language with a rich fount of speech, by which the expansion and exchange of ideas has been facilitated, and which, in conjunction with science, has become a power encircling the entire earth. In place of the miserable sparks obtained in the infancy of mankind by rubbing together pieces of wood, and replaced some thousands of years later by flint and steel, or pyrites, we have to-day at our command matches which may be kindled in a moment ; gas, oil and electric light illuminate the darkness, and steam, produced and controlled by fire, drives the various machines by which we manufacture our industrial products and convey them at express speed over land and sea. We overcome the influence of cold by warming our dwellings, and by the use of clothes, which can be modified according to the condition of the temperature ; and we have learnt to con- struct a host of vessels and tools of iron which enable us to fashion any substance to suit our wishes. With regard to the question as to whether man during the course of his development in the past has at some time over- stepped the barriers which now divide him from the beasts, Wundt thinks that we can certainly give an affirmative answer. This is shown by human history. For as man during his in- dividual development passes from simple association of ideas to a condition of intellectual consciousness, so the whole race has once passed from a state of nature to a state of culture. In contrast to man's struggle and progress from savagery to civilisation, the further question arises whether it is to man alone that this spiritual development has been granted, or whether animals also can rise to higher things. Wundt, dealing with this question from the point of view that animals have only a simple power of associating ideas and no actual in- tellectual capacity, thinks that for them any such spiritual de- velopment is in the highest degree improbable. He considers the psychological organisation of animals so circumscribed that further development can only take place within certain narrow 24* 372 THE HUMAN SPECIES limits. These limits, however, are not so very narrow. Many of the higher wild animals, whose existence is threatened with extinction, or with diminution, by man, most certainly develop higher intelligence as the result of the struggle for existence aided by extended experience. This has undoubtedly taken place among the domestic animals which man has chosen for his close companions, namely, the horse, and still more, the dog ; whereas the others, namely, the sheep, cattle and swine, have attained to no improvement over their condition as wild animals, but have rather suffered some diminution in intellectual capacity. The opinion of a naturalist of Brehm's eminence is particularly interesting in this connection. Speaking of the intellectual powers of the apes, he says, " The mental superi- ority exhibited by apes over other mammals (excepting man) is by no means so great as is commonly supposed ". Brehm does not deny that they possess a certain degree of reflection, a good memory, cunning, craft, and the power of dissimulation ; they can also express love and affection. As compared, how- ever, with man, he drily observes, " Man increases in judgment and wisdom with the years ; the ape can only be taught when young, the brute in him becomes more and more prominent with age ". Can any races be found among the savages now existing who have any prospect of developing into civilised people ? We think it is hardly possible. Human history has long since drawn the dividing-line between the races who are sluggish, cowardly and retrogressive, and those who are energetic, brave and progressive ; to the latter belongs the victory, whereas the former either die out, or stagnate in lazy passivity. The present savage races are not, as is often erroneously assumed, degenerates, but, as Homes has strikingly demonstrated, are those which remained impoverished and stationary after the migration of the stronger elements. Christianity can effect but little change in them ; it can but cover them with a thin varnish of civilisation, under which remains their primitive savagery. The history of the German South-West African war is a striking instance in point. And now as to the civilised nations. Will civilisation always continue to advance, and man attain the position of PSYCHOLOGY 373 super-man ? Many, perhaps, do not doubt that this will be so. They point with pride to the tremendous advance which occurred between the hypothetical speechless man of the tertiary epoch and the man of the diluvial period, endowed with speech and using fire and tools ; then from this to the barbarians of the later Stone Age, who cultivated fields and tamed animals ; then on through the dawning culture of the Bronze and Iron Age to the civilised races of ancient and modern times. Is not a vast intellectual advance, they ask, apparent here? Charles Morris (The American Naturalist, 1886) thinks the way of civilised man must lead to still greater heights of intellect. Man to-day cannot be the end product of intellectual development ; he is only the beginning of a new developmental process, in which the brain will attain still further supremacy over the body, and the final product will be a being of whose structure we can form no adequate con- ception. This is the actual super-man which Nietzsche evolved as the result of the continual progress of development. Branco, how- ever, in the clever chapter which ends his essay on the supposed human teeth found in the Swabian Alps, inquires " is it not logical to regard this super-man not as an end-product but as a stage after which further super-men may follow ? And again, is it absolutely necessary that development must always take place in the same direction ? The history of many organisms shows that development may lead to a bad end, and that instead of leading to victory in the struggle for existence, it may, on the contrary, lead to defeat." Branco cites the machaerodus as an example in palaeontology. In this animal the powerful and saw-like incisor teeth grew to such a size that eventually the animal could not open the jaws sufficiently widely, and so the species died out. Branco therefore thinks it impossible that the progressive enlargement of the human brain for thousands and thousands of years can take place without the body of the super-man becoming progressively feebler, until it dies out owing to its inability to nourish or defend itself, or to propagate its species. At what period has human civilisation now arrived ? My own opinion is that we are still on the upward intellectual path, 374 THE HUMAN SPECIES and that this is undoubtedly proved by the advances made during the last century, and especially during its latter half. During the twentieth century we shall make still further dis- coveries in the heavens and on the earth ; we shall make still more improvements in the construction of our machines and in the conditions of life. But the struggle for existence, which even now is fierce enough, will become still more determined owing to the increase in the population ; whether in the course of future ages it will be possible for the body to keep pace with the feverish activity of the brain is a very open question. I am far from asserting, as does R. Arndt, that all genius, and even talent, or superior endowment of any kind, is a sign of degeneration. It cannot, however, be denied that civilisation itself, especially in its most advanced form, carries with it certain risks to the minds and bodies of men. At the present time it is no secret that the increase in cases of neurasthenia, insanity and suicide must be attributed to the struggle for existence, especially when the harassed brain has been spurred on by alcohol, as so frequently happens. In civilised races we often see increase in intellectual power go hand in hand with a narrowing of the jaw and an early loss of the teeth ; in men premature baldness, and in women inability to suckle their children. In both sexes we find imperfect development of the thorax, and consequent predisposition to tuberculous disease of the lungs. In the third part of this work we shall deal with the pathological changes peculiar to man, as well as with those which he exhibits in common with other animals. It is impossible to foresee whether hygienic efforts will be able to keep pace with the knowledge of these risks, and so be ever more and more able to ward off degeneration from civilised peoples. Instead of prophesying an unlimited advance for mankind through future ages, it would seem more rational to withhold our judgment, as does Branco, for " when we rashly attempt to explore the future, we find, instead of an answer to our questions, that a bandage is laid across our eyes ". C. Comparative Pathology and Pathological Anatomy. As human characteristics are illustrated by a comparison between the behaviour of men and that of animals so the pathological side of the question, as well as the anatomical and physiological, must be treated by distinguishing general and special processes. By comparative researches of this kind we can determine which pathological changes, both of external and internal origin, are common to man and other animals, and which others are proper to man alone. I. General Pathology and Pathological Anatomy. Comparative pathology and histology teach us that the foundation of all animal bodies, including man's, is the cell from which the primitive tissues are developed, aggregations of which go to form the different organs and parts of the body. Comparative physiology further teaches that the chemical composition of similar cells, tissues and organs in all animals, including man, is practically identical, and that what we know as life is manifested as a chemico-physical process in the cells. Further, since disease is only life under altered conditions, consisting of deviations from the average as regards shape, re- lationship or activity, human and animal pathology must be regarded as essentially a cellular process, and the remarkable changes which take place in the diseased cells, tissues or organs must be admitted to be, to all intents and purposes, the same both in man and in animals. Pathologically, this correspond- ence between the two is first noted when we consider the causes of disease. The animal body is directly damaged by anything which 375 376 THE HUMAN SPECIES alters the composition of the tissues, either mechanically, as by external violence, or chemically, as by the presence of noxious vapours or gases in the atmosphere. Injury may be also brought about by extreme changes in temperature, such as chilling or freezing, heating or burning, and by extreme rarefaction of the atmosphere at great heights; this, however, is well borne by certain animals (e.g., the condor), though man and other animals are severely affected by it. Other direct causes of disease, of a specific nature, are parasites and poisons. Animals are also susceptible to the indirect causes of disease ; but this is less easily seen in wild animals than in domestic animals, whose constitution, hereditary disposition, age, tempera- ment and sex play an important part. The symptoms of the processes of disease in man and animals, do not merely consist in the elevation or depression of the body temperature and the concomitant sensations of heat or cold, but in other elementary anomalies of function, such as pain, or loss of sensation, or spasms and motor paralysis. Diseases may, in all cases, end either in complete recovery, in one or more relapses, in chronic illness, or in death ; the last may occur either with or without a struggle ; may be sudden, or in the form of a gradual decline. In the last case the symptoms observed in man do not differ from those seen in the higher animals ; psychical activities fail, sensation gradually disappears, the temperature becomes irregularly distributed, and the muscles suffer a general loss of power. Man, however, differs from all other animals in one point, and that is in his tendency to suicide. No animal, even when suffering from the most severe and painful disease, ever brings its own life to an end. All the cases of apparent suicide in certain animals which are detailed in works on natural history and other publications, can easily be otherwise explained if a little quiet thought is given to the matter. Even the scorpions, which if placed in a ring of burning coals run directly into the flames, behave in their rage like other animals, or even like man — they lose their heads and rush on to their own destruction. There is never any clear intention of suicide. GENERAL PATHOLOGY 377 Anatomically, similar changes in the cells, tissues and organs correspond to similar pathological conditions. The same changes in the blood as are evidenced by hyperaemia, hae- morrhage and anaemia can be seen in all red-blooded animals just as they are seen in man. The same thing is true with regard to the unorganised de- posits (concretions, atheroma, fat), the formation of water and gas, and especially organised new growths consisting of blood vessels, muscle, nerve, glands, cartilage, bone, connective tissue, epithelium, true skin, mucous membranes and serous mem- branes; not to mention malignant new growths composed of cells with or without intercellular substance, or connective tissue stroma, and swellings due to tubercle or abscess formation. Inflammation plays an important part in comparative pathological anatomy, the well-known result of irritation which causes a quantitative and qualitative increase in local metabolic processes, and which varies according as the organ which is attacked possesses a rich capillary network of its own between the cells, or only experiences an influx of plasma as the result of irritation. The inflammatory reaction often goes on to the formation of pus-cells ; in other cases permanent new tissues are formed (connective tissue, vascular tissue, bone, etc.), or a degeneration of the cellular elements occurs. Pathological degeneration may take place, both in man and animals, without any preceding inflammation. Tissues may undergo fatty or granular degeneration, may become calcified or pigmented, or may be converted into a mucous or cheesy granular mass. Senile atrophic and degenerative changes occur in animals, especially domesticated animals, as well as in man. Portions of the body may be destroyed by moist, or dry gangrene, a process which in young persons is sometimes due to extremes of temperature (freezing or burning), and some- times to mechanical violence. When a man or animal dies the phenomena of dissolution are identical in both cases : the skin becomes bloodless with post-mortem lividity in the dependent parts; rigor mortis followed by relaxation occurs ; fluid collects under the skin and within THE HUMAN SPECIES the body ; gas is set free, and the blood coagulates in the veins and right side of the heart. The acquired hypertrophies and atrophies of certain parts of the body (such as acromegaly and the stunted growth of rickety children) are not the only ones which are included in the domain of comparative pathological anatomy. All congenital anomalies, whether affecting the whole body or only a part, are not less common among animals (at any rate among domestic animals) than among men. Giants and Dwarfs. — A man 190 centimetres (6 feet 3 inches) is abnormally tall ; giants proper are men who reach at least 200 centimetres (6 feet 6 inches), but their maximum height cannot be definitely settled. Their bones alone are hypertro- phied without a corresponding in- crease in the size of the muscular, nervous and vascular systems. They are therefore less resistant to exter- nal influences, they are sluggish and have little energy, and are usually incapable of reproduction. This applies less to the shorter, thick-set giants with large trunks and almost normal limbs, and more to the lanky FIG. 191. Giant tadpoles of Rana long-legged ones, the upper part of esculenta, J natural size. whose bo(jies js short Those Qf the first type are often shown post-mortem to be subjects of acromegaly with tumour of the pituitary body in the brain. Giants seldom live to any great age. Giants are less common among animals than dwarfs. Among wild animals giants have been found in all classes and orders (for example, among stags, elks, turtles, salamanders, sharks) ; these forms, however, which have become fixed species are of less interest than those which under peculiar circumstances have exceeded the normal size, as, for instance, the enormous pike and carp of certain lakes, and the tadpoles which were found in a wet secluded grave at Frankfort-on-the-Main by Brugsch.1 1 Brugsch, C., "Ueber Riesen- und Zwergformen bei den Betrachiern," Zoolog. Garten, 1864, p. 349. GENERAL PATHOLOGY 379 They were half as long again as the normal animal, and their size was attributed to their having had an excessively rich diet of small water animals which inhabited the mud. The domestic animals show the influence of diet in producing giants ; con- tinued selective breeding has produced large horses, cattle, pigs, sheep, dogs, cats and rabbits, besides giant geese and ducks, and pigeons the size of fowls. Dwarfs are much more common than giants, and there are whole races of them in Africa, Eastern Asia, some of the Sunda Islands and in America ; their small size is hereditarily transmitted. These pygmies (Fig. 192) have well- proportioned bodies, though their heads are disproportionately large and their arms are too long. Similar pygmies were found in France in palaeolithic times, and in Switzerland in neolithic, and according to Sergi are still quite common in Italy as descendants of the African pygmies which had wandered over the isthmus which once united Africa to the south of Europe. In the fact that their bodies though short are well proportioned, these pygmies closely resemble the much smaller dwarfs which are occasionally born of nor- mal parents and among normal brothers and sisters. These elegant lilliputians have a generally infantile appearance and have never produced any offspring. They are FlG- the result of a total inhibition of develop- ment during intra-uterine life ; there are, however, other dwarfs who when born are normal and like other children ; in the course of their further growth, although the body becomes nor- mally long and powerful, the extremities remain short, and thus their height remains that of a child. These are giants when they sit down and dwarfs when they stand up. Another pathological variety of dwarf is that which remains small and stunted as the result of rickets ; and then there are the saddest of all, the Cretins (Fig. 193), in whom the thyroid A Bush W8my- (After Fritoch.) 380 THE HUMAN SPECIES gland is either completely absent or much degenerated ; not only are their fat bodies and large heads imperfectly de- veloped, but their mental faculties are similarly retarded. The circumstances noted with regard to human dwarfs also obtain among animals. There are dwarf races among animals corresponding to the pygmies among mammals, birds, fishes, snails, butterflies and beetles. As normal parents here and there produce a lilliputian child, so among the normal litters of domestic animals absurdly small but well-proportioned and elegant individuals are occasionally born. As rickets, too, re- duces human children to dwarfs, so young calves, horses, dogs, and also the young of beasts of prey kept in zoological gar- dens,1 remain stunted in growth as a result of rickets. Cretinoid animals would also occur were they not soon put out of the way as useless and imbecile consumers of food. I only re- member seeing a single case of a full-grown cretinoid animal. There are also dwarfed ani- mals whose growth has been interfered with by external cir- cumstances without any such pathological changes. These FIG. 193. Cretin. (Virchow.) conditions have been studied in batrachians and fishes by Klunzinger.2 He was able to recog- nise the following circumstances as conducive to the production of these stunted forms : scarcity of food, too low a temperature in the water (as for example in alpine lakes and pools),, too little light at great depths, insufficient volume of water and thus insufficient space for movement and exercise. The dwarf forms among fish have gradually become races and species, but under more favourable conditions they may regain their normal size. Klunzinger cites the river trout (dwarfed sea trout), the torsk (a dwarfed Codfish), the small East sea herring, and the dwarf perch. 1 Friedberger und Frohner, Spez. Path. a. Therapled.Haussaugetiere, i., p. 714. "Jaliresh. d. Ver.f. vaterl. Naturkunde, 1900, p. 519. GENERAL PATHOLOGY 381 Deformities. — Forster, from whose works the main part of the following chapter is drawn, has classified deformities gener- ally into those involving simple deficiency, stunting or small- ness of the body, and those due to arrested development. All these phenomena, which play so sad a part in the life-history of men, are caused by diseased processes occurring during the early development of the foetus; these processes so disturb the permanent form of the mature individual, that the whole body (or a part of it) becomes misshapen. The causes are hereditary influence, pathological changes in the ovum or spermatozoon, general or local disease of the mother, or ex- ternal mechanical influences. The processes of hypertrophy and atrophy, inflammations and hydropic conditions which occur during the inter-uterine life of the foetus can only be recognised by their consequences after it has been expelled from the uterus. (a) The worst examples of deformity owing to imperfect development are the formless carneous moles, headless trunks or trunkless heads. Those with imperfectly formed skulls, brains or faces are equally incapable of life, but this is not the case with the microcephalies (produced by premature closing of the bones of the skull), or with those in which the backbone, the thorax or the limbs are imperfectly developed. These deformities are possible among wild animals, and the paucity of reported cases is probably due to the fact that the old animals immediately destroy them. The teratological preparations in veterinary museums are nearly always from domestic animals. With the exception of microcephaly, the possibility of which among animals I am not at all disposed to doubt, deformities from imperfect de- velopment are fully illustrated by the domestic animals. Much is recorded in the literature of the subject. Darwin ( Variation of Animals)1 has published a series of striking examples. Thus he mentions a pig which was born without hind-legs, the deformity being transmitted through three generations. In a litter of rabbits one was born with only one ear ; from this a whole race of one-eared rabbits was produced. Exactly analogous to the cases of hereditary baldness among men 1 Darwin, loc. cit., vols. iii. and iv. 382 THE HUMAN SPECIES associated with complete or partial absence of teeth, are the hairless dogs with incomplete dentition, especially the incisors, the canines and pre-molars. The most interesting cases of deformity owing to imperfect development are those in which an acquired deformity is transmitted, a possibility which is still very irrationally dis- puted. Darwin relates, as absolutely credible, the case of a child with a shortening of the little finger of the right hand whose father had lost the same finger ; also the case of a man whose eye had been removed owing to suppurative disease, and whose child had micro-ophthalmos on the same side of the head. Acquired defects are also transmitted in animals, such as dogs, cats, horses, cows. It is not known with certainty whether all tailless cats and dogs are descended from ancestors who once lost their tails by mechanical violence. The fact of its occasional occurrence cannot, however, be denied. A stag which had lost one antler produced one-antlered progeny, and a cow, one of whose horns had been lost owing to sup- puration, afterwards brought three one-horned calves into the world. (/?) The deformities caused by FIG. 194. Hare-lip. (Bardeleben.) arrested development are either due to the persistence of an earlier embryonic condition till birth, or to an error in the original development of the part. They are common to animals (domestic) and ' man. They result in fissures (Fig. 194), or in the closure of cavities and canals which are normally open, in the union of normally separate parts, and in the stunting and deficiency of certain organs. In this class may be included the complete or partial union of the small bones of the extremities which normally are separate. In man" the congenital union of two or more fingers in one or both hands may occur in varying degrees. It may be merely a kind of partial webbing, or may be a complete union of the skin of two fingers right up to the knuckles. Web- GENERAL PATHOLOGY 383 feet are found also in certain dogs (e.g., Newfoundlands), and by heredity have given rise to whole races. It is still more re- markable that this abnormality may also occur in fowls, for example the Polish fowls which Darwin describes ( ]^ariations in Plants and Animals))- Finally, Forster includes in this class the hermaphrodites. A priori it would seem more correct to include individuals possessing both male and female sexual organs in the category of those with redundant development, and not of those in which development is impaired. The history of_ development shows^Jiowever^ that in all metazoa both sexual organs are originally_presf:nt, anTTthat^ with the exception of the normally hermaphrodite animals, one sex is developed at the expense of the_otijer,_aft€r a certain period of embryonic life. I have, however, shown elsewhere, that the undeveloped organs are always present in a latent condition. When this fact is re- membered it will be seen that hermaphrodism is in reality an arrest of the process by which one or other of the sexual organs is suppressed or atrophied. Cesare Taruffi, to whom we owe a new and excellent ex- position of this difficult subject,2 has formulated two main divisions, one that of the true anatomical hermaphrodites, and the second that of the clinical or external pseudo-herma- phrodites. Anatomical hermaphrodites may be considered as genuine when both sexual glands are present in the same in- dividual. This is always rare, but occurs in man and also in other mammals, in birds, in batrachians, and other amphibia and in fishes. Another class of true hermaphrodites is that called by Taruffi atrophic or neutral. In these the glands are rudimentary and sex indeterminate ; examples occur in man, dogs, goats and cattle. The third class or false hermaphrodites comprises men with female appearance due to persistence of the Miillerian ducts, and women with a masculine appearance due to persistence of the Wolffian bodies. Taruffi cites as examples among animals a lamb, some hares and a stag, eight swine, eight calves, an ass, two sheep, four goats, several horses, a bitch, a steer, an ox, a ram and a newt. 1 Darwin, loc. cit., iii., p. 288. 2 Cesare Taruffi, Hermaphroditisnnts und Zeugungsunfdhigkeit, Berlin, 1903. 384 THE HUMAN SPECIES The cases of clinical hermaphrodism are not less numerous. Among these are classed the men with female appearance, character and breasts, and women with masculine appearance, hypertrophy of the clitoris and beards. The cases of men with female breasts (gynaecomastia) are fairly common ; this is not to be wondered at if we assume with Darwin that the male mammary glands- are^ot Tudimentary but merely imperfectly developed, and so not functionally active organs. On the other hand, the accounts of men and male animals with glands which were capable of lactation should be received with extreme caution. In the first place, certain male animals may be ex- cluded, which after castration developed large nipples and eventually secreted milk, as these do not come under the category of deformities. Setting these on one side, there still remains a very small number of genuine cases in which men after their wives have fallen ill have suckled their children. These cases have been collected in Ploss-BartePs great work, Das Weib, and include a peasant in Arenas in New Andalusia (Al. v. Humboldt), an Ojibbaway Indian (Wenzel Gruber), and a Greek master shipbuilder (Ornstein). An analogous case in the animal world has not been demonstrated. Taruffi includes in a special division of clinical herma- phrodism urethro-genital deformities which often give rise to doubts as to the sex of human beings and animals. On the one hand, men with a divided scrotum cryptorchis and a small hypospadic penis may be mistaken for women, and, on the other hand, a large clitoris may simulate a male penis. Many such cases are illustrated in veterinary journals, and attested by the original specimens, which though called pseudo-herma- phrodites are merely deformities caused by hypospadias. In all the phenomena hitherto described as anatomical and clinical hermaphrodism, analogous examples may be found in men and animals. In one matter, however, man has a monopoly which is hardly creditable to himself, namely, in what is known as sexual perversion. -Actual homo-sexuals (Krafft-Ebing) appear not to exist among animals. TJie__aJtempls__of--d©gs- with-dogs and cows with cows are_noL_xiue— to- any. inveterate, inborn homo-sexuality, but merely to a foolish eroticism wrnch dis- GENERAL PATHOLOGY 385 appears as soon as an opportunity for the natural exercise of the function occurs. It is very different with human homo- sexuals, who are mostly so from birth. And here again we must distinguish true homo-sexuality from the irregularities of blase wastrels. Normal thought and feeling cannot explain how a man can choose another man for active sexual action, or a woman passively submit herself to another woman. But when a man with female instincts submits to another man, or a woman with male instincts chooses another woman to satisfy her desires, Taruffi is entirely right in regarding this as psychi- cal hermaphrodism, as these abnormalities can only be ex- plained by supposing that the opposite sexual powers have remained present in a latent form. FIG. 195. Hen with cock's plumage. Darwin has collected instances of the appearance in animals of secondary sexual characteristics which had hitherto been latent. Among domestic and wild birds (fowls, peacocks, ducks, partridges and pheasants), for instance, the hens have after a time developed cock feathers (Fig. 195) and behaved like the cock birds. In the same way does from some cause which has aroused the latent male potentiality have developed antlers.1 Males have also assumed female characteristics, as among domestic fowls when the cocks sometimes take the appearance and manner of hens.2 1 Darwin, loc. cit.. iv., p. 58. 25 2 Ibid., iii., p. 280. 386 THE HUMAN SPECIES Tailed people do not exist, though they were supposed to till quite recently. Instances of men with tails occur, however, owing to developmental errors during foetal life (Fig. 196). Virchow thought that this could only be considered as a rever- sion to an animal type when there could be shown to be an actual increase in the length of the spine. He did not consider every case in which the terminal portion of the spine and its coverings were free as reversions, still less the tails composed of soft parts only which he compared to stumps of tails. Bartels, Wiedersheim and Ornstein explain their origin differently. Since embryologists admit that man has descended from ancestors who had free tails, the tails, often I2'5 cm. long (nearly 5 inches), consisting of connective tissue, fat and blood vessels, can only be ex- plained as a prolongation of the so-called tail-fibres, and the large overgrown vertebral tail consisting of a joint-like elongation of the caudal spine must be re- garded as a reversion. Man is not the only animal in which these reversions oc- cur ; they have also been FIG. ic Tail on a boy, six months old. (Granville Harrison.) observed in the Inuus ecan- datus, the gorilla, the orang and the chimpanzee. (c) Deformities due to supernumerary parts are usually noticed in an increase in the number of the fingers, toes, vertebrae, ribs, breasts, teeth and jaws, but also occur in the internal parts such as the tongue, spleen, etc. Supernumerary fingers are the most common (Fig. 197), supernumerary toes being next, arid almost as frequent. There may be only a small appendage covered with skin but without bones, or a proper finger with the normal number of phalanges. Usually one digit only (a thumb or little finger) is present, but the number of supernumerary digits may amount to a complete double set. In accordance with the law of correlation, both hands and both feet are equally deformed, and the malfor- mation is hereditary and is present in several 'generations. Ac- FIG. b. FIG. e. PLATE IV. Deformities. FIG. a. FIG. d. FIG. c. FIG. f. FKJ. a, The fused twin Helen and Judith. FIG. b, Fusion at sternum. FIG. c, Two heads and fusion of trunk. FIG. d, One head and two bodies. FIGS, e and f, Fusion of lower limbs. (Ranke, Der Mensch.) GENERAL PATHOLOGY 387 cording to Darwin's investigations, the deformities are not confined to Europeans but occur in negroes and other races. In animals with four toes on their fore-feet, a fifth super- numerary toe has often been observed ; the deformity is still more common on the posterior extremities. Dorking fowls have five claws on their feet ; dogs and cats, the large newt and the frog are often seen to have six toes on their hind- feet.1 Supernumerary breasts are not uncommon in women. They are generally symmetrically placed, but may occur irregularly on any part of the body, e.g., the shoulder, thigh or axilla. They frequently secrete milk.2 In domestic animals' supernumerary udders the cause is found in the abnormal activity of two usually rudimentary teats ; Darwin quotes instances of a sheep with four, and a cow with six teats. Another form of this kind of deformity is seen in " mon- c b a FIG. 197. Supernumerary digits, a and b, in the hand ; c, in the foot. (Ranke.) sters," which are produced by the division, or duplication, of the primary layers of cells. They occur both in men and animals, and when they survive are exhibited in shows, and when incapable of survival find their way into museums of pathological anatomy. The division may begin either at the cephalic or caudal end of the embryo, or at both simultane- ously. This explanation is recent ; formerly it was supposed that double monsters arose from the junction of two originally separate embryos, developed from -separate ova. If the divi- sion begins at the cephalic end, monsters are produced with two heads, two faces or two heads and two thoraces (Plate IV., fig. c) ; or with two heads and bodies and four lower extremities, double men only united by the sacrum and rectum (Plate IV., fig. a). When the division begins at the caudal end, either a monster with double lower limbs is formed, with two pelves 1 Darwin, loc. cit., iv., p. 14. 2 Ibid., iv., p. 65. 25 * 388 THE HUMAN SPECIES and genital organs, a single body and head (Plate IV., fig. d), or the so-called " Janus-head " is produced. In this monster the lower part of the body is double, and the two heads, necks and breasts are conjoined. Lastly, a completely double body may occur and the heads only be conjoined either by the temples, occiput or forehead. When division begins from both ends of the embryo, the monster often lives and is seen in exhibitions. They are united only by the thorax or abdo- men (Plate IV:, fig. b). The union may extend to the neck and jaw ; in other cases there is a single backbone; finally, there are cases in which as a result of cell-division, a stunted FIG. 198. Supernumerary milk glands. C, in a Japanese female ; D, in a Baden soldier. individual incapable of separate existence is attached to the epigastrium of another, or is enclosed in his abdominal cavity. Calves and other domestic animals with two separate heads, two faces, " Janus-heads," limbs growing out of their backs and similar double monsters are not infrequent. They also occur in wild animals. Hunter and others have observed lizards with two tails and Lereboullet has carefully studied fifteen cases of fishes in which the gradual union of two previously separate heads has given rise to a double-headed monster.1 (d} Excessive development of hair on the face or body combined with poor development of the teeth is a rare 1 Darwin, loc. cit., iv., p. 386. GENERAL PATHOLOGY 389 monstrosity, and is peculiar to man, owing to the fact that he is usually hairless except in certain regions (Fig. 199). This monstrosity is always considered most remarkable, especially as it is hereditary. Darwin mentions a Siamese family in which the face and body were covered with long hair in three successive genera- tions.1 In another case in a Burmese man the face and the entire body, with the exception of the hands and feet, were covered with fine silky hair which on the back reached a length of five inches. Only the incisor teeth were present. One of his daughters had the same peculiarity, and her appearance was even more singular, as the nose was covered with thick soft hair. FIG. 199. Russian hairy man. (Ranke.) FIG. 200. Julia Pastrana. (After Haeckel.) The family of the Russian hairy man were similar in ap- pearance, their faces, which were completely covered with hair, resembled that of a poodle or Skye terrier. The most celebrated instance was the Spanish dancer Julia Pastrana (Fig. 200). The whole of her face was covered with hair as was also her chest ; she had a beard and a double irregular row of teeth in both the upper and lower jaws. The face of the foetus is covered throughout with downy hair, which during the fifth month is longer than that on the head. Darwin, therefore, is inclined to consider the hairy man as a reversion, that is to say, a persistence of the embryonic condition. 1 Darwin, loc. cit., iv., p. 4. 390 THE HUMAN SPECIES II. Special Pathology and Pathological Anatomy. In the foregoing pages the outlines of general human and animal pathology and of pathological anatomy have been described. Special pathology and pathological anatomy will now be dealt with and similarly compared ; we shall see in what way man occupies a special position, and in what way he resembles other animals. In order to make our survey clearer, internal pathological conditions will be divided into infectious and non-infectious diseases, and these again subdivided. This will be followed by a short comparative description of surgical diseases, of diseases of the eye, nose and ear, and finally by an account of compara- tive obstetrics. i. Internal Diseases. (a) Infectious Diseases.1 Cholera, the organism of which was described by Koch in 1883 (Plate V., fig. i), is only seen primarily in man. Spon- taneous cases do not occur among animals. The cases of a chimpanzee and other animals in the Zoological Gardens of Antwerp and Amsterdam, which were reported by M. Schmidt during the cholera epidemic in those towns of 1830 and 1831, cannot be regarded as genuine merely because the animals exhibited choleraic symptoms. Watery stools, vomiting, thirst, dry lips, bluish colour and coldness of the skin, and a small and very rapid pulse are symptoms which may be set up simply by acute intestinal catarrh. Experimentally, however, the majority of animals can be infected by injections of human cholera stools or by pure cultures. Guinea-pigs are especially susceptible. The animals exhibit symptoms absolutely similar to those seen in man, and post-mortem show the characteristic reddening and loss of epithelium in the intestine (Marx). 1 Friedberger und Frohner, Spcz. Pathologic der Haussdugetiere, 5th edition. Stuttgart: F. Enke, 1900. Marx, Experimentelle Diagnostik, Serum- therapie und Prophylaxe der Infectionskrankheiten. Berlin : A. Hirschwald, 1902. Schmidt, M., Zoologische Klinik. Berlin : Hirschwald, 1870, vol. i. ; 1872, vol. ii. INTERNAL DISEASES 391 The same is true of enteric fever (Plate V., fig. 2), with a few minor differences. It is a disease originally peculiar to man, which does not primarily occur in animals. On the other hand, most experimental animals are suscept- ible to this disease. But the characteristic typhoid symptoms are absent, and at the autopsy, except in the case of apes,1 the typhoid ulceration is not found in the small intestine. The animals simply die of typhoid septicaemia (Marx). Fowl typhoid or fowl cholera is a disease which is never communicated to man, but at certain times numbers of fowls and other birds die of it. Infection with the short non-motile bacillus produces profuse diarrhoea, rapidly increasing weakness and cramps. In contrast to cholera and enteric fever plague does not attack man only, but also primarily affects other warm-blooded animals, including apes, rats and mice. Birds, horses, cows, sheep and goats are quite insusceptible to the bacillus dis- covered in 1894 by Kitasato and Yersin. These animals are, however, susceptible to the poisons contained in the bodies of the bacilli ; recently it has been discovered that fleas and flies may become fatally infected, apparently from rats. If the skin of a guinea-pig is artificially infected with the plague bacillus, pustules containing the organism form on the skin and the animal dies ; haemorrhagic cedema of the subcutaneous tissue takes place, and the lymphatic glands are considerably enlarged (Marx). The bacillus of tuberculosis, first discovered and investi- gated in pure culture by R. Koch, is not only pathogenic for man, but also for guinea-pigs, rabbits, rats and dogs. Accord- ing to M. Schmidt, it is the most frequent cause of death among the apes and large felidae in the Zoological Gardens, whereas bears and the smaller beasts of prey are less frequently attacked. The only distinction between man and these animals is that in the latter tubercles are not formed in the viscera, though they are loaded with tubercle bacilli and undergo finally the same destructive process. Fowl tubercle and bovine tubercle are somewhat specific, although there is no doubt that all these kinds arise from a 1 Grunbaum, B. M. Journal, 1905. 392 THE HUMAN SPECIES common stem (Marx), and may be grown on suitable media at 37°~38° C., although the optimum temperature is4O°-4i° C. Cultures are somewhat slimy in character and cannot be inoculated into guinea-pigs. As yet it has not been found possible to convert fowl tubercle into mammalian tubercle or human into bovine tubercle by experimental methods. Koch indeed considers that the transmission of human tubercle to cattle has been shown to be impossible.1 Cattle may become immune to infection with human tubercle without any apparent illness. The " Perlsucht " of cattle arises from another bacillus, very closely related to the human, and is not, as Behring states, identical with the latter.- A pathogenic bacillus closely related to that of tuberculosis is the bacillus of leprosy (Plate V., fig. 3), although numerous researches and experiments have shown marked differences between the two diseases. It is a remarkable fact that the bacillus of leprosy cannot be cultivated, and a still more remarkable one that it occurs almost exclusively in human epithelial cells. The main point of difference consists in the fact that leprosy is an exclusively human ailment and has never been communicated to animals. The bacillus of diphtheria discovered by Klebs in 1883, and Loeffler in 1884, in addition to man attacks both cats and horses, and, according to Schmidt, apes may also be infected, though spontaneous infection in these animals is rare. On the other hand, all mammals, with the exception of rats and mice, and also fowls and pigeons, may be artificially infected. When guinea-pigs are infected the lymphatic glands are enlarged, the animals become weak and cyanosed and die of suffocation. The post-mortem appearances are similar to those seen in man, viz,, haemorrhages, oedema, serous effusion into the pleura, pericardium and peritoneal cavity, and considerable engorge - 1 The possibility of such an infection was proved at the Imperial Society of Hygiene in 1905. 2 Dr. Paul Bartels -has brought forward interesting evidence before the German Anthropological Society at Gorlitz (1906), showing that tuberculosis has been one of the deadliest enemies of man from the earliest times. In a neo- lithic grave, together with tools, he found human vertebras showing clear signs of tuberculous disease which had healed, leaving an " angular curvature ". INTERNAL DISEASES 393 ment of the internal organs. The proper fowl diphtheria differs from the human variety, and is caused by a special bacillus of a different type. The bacillus which gives rise to lockjaw or tetanus prim- arily attacks many mammals ; it is, however, specially dangerous to all kinds of horses ; it may be conveyed by infection to other mammals, especially guinea-pigs and rodents, whereas fowls are nearly insusceptible to the tetanus poison. Cases occurring spontaneously, or due to artificial infection, exhibit the same symptoms, viz., muscular contractions, gradually in- creasing in severity, till life eventually becomes extinct owing to paralysis of the respiratory muscles ; these phenomena also occur in man. The causal organism of influenza was long sought for and eventually discovered by Pfeiffer in 1893 (Plate; V., fig. 4). Man alone is attacked during any epidemic, and it was long thought that animals could not be artificially infected. Pfeiffer, how- ever, has succeeded in conveying the disease to apes. The influenza ("Pink-eye") in horses is not identical with the human disease, and is caused by a different organism. Whooping cough, not only in its symptoms, but also in its almost absolute limitation to man, resembles influenza most nearly. It has not been determined whether the short thick bacillus described by Jochmann and Krause is the actual cause of this disease. As long ago as 1873 tne spirillum discovered by Obermeier was recognised as the cause of relapsing fever (Plate V., fig. 5). Tictin discovered that the transmission of the spirillum, and with it of the disease, from man to man took place by means of the bed bug, and that apes could be infected by crushed bugs. As far as is now known spontaneous cases occur only in man ; even fowls are not attacked, though whole nests of bugs are often found in fowl-yards ; we must conclude from this that relapsing fever is peculiar to man, and that when bugs attack and infect fowls, they are immune to the spirillum. R. Koch reported on his return from German East Africa that African relapsing fever was only a variety of the European, and was caused by a spirillum of rather larger size. He charged a kind of tick (ornithodorus monbata) with being the 394 THE HUMAN SPECIES carrier of the infection ; as this is found on rats and apes it is possible that these animals also are infected, as well as man. This would form an important distinction between the African and European recurrent fevers. All the diseases hitherto described have been caused by bacilli. Pneumonia illustrates the transition from the bacillary to the coccal form of organism, as both the bacillus of Fried - laender and the coccus of Fraenkel play a part in its causation (Plate V., figs. 6 and 7). Inflammation of the lungs caused entirely by the bacillus only occurs in man. Artificial infections have a marked effect only in mice and guinea-pigs ; rabbits are immune. The pneumococcus, on the other hand, gives rise to spontaneous attacks not only in man but also very frequently in animals ; in all cases of artificial infection the appearances in the lungs and other organs are similar to those found in man. We will now pass on to the description of the remaining diseases caused by cocci, of which we may remark that their influences both locally on the tissues and generally on life and health is the same in man and in the other animals. The danger to life is less with the staphylococci which produce pus ; both in man and animals, and in the latter also under experi- mental conditions, pus formation, abscesses and boils are produced. Streptococci are more dangerous, not only on account of their tendency to increase in the body of the patient, but also on ac- count of their power to set up erysipelatous inflammations, and so to produce general blood-poisoning, or sepsis. As regards this there is no difference between man and other animals. Malta fever is a disease peculiar to man, and commonly observed among the inhabitants of Malta. The cause of the disease had been vainly sought for some time, when Bruce in 1896 discovered and described the coccus Melitensis (Plate V., fig. 8). Recent investigations by the English Commission has shown that the goat acts as-a carrier of the organism, and through its milk transmits the disease to man. Inoculation experiments with cultures of this coccus produce in monkeys (and in these animals only) a fatal disease showing the same symptoms as that in man. Acute articular rheumatism and meningitis are diseases caused by cocci in combination with some other agent. In PLATE V. Bacteria, cocci and amoeba primarily pathogenic for man. FIG. r. Cholera bacilli. Lehmann and Neumann's Atlas.) FIG. 2. Typhoid bacilli. (Lehmann and Neumann's Atlas.) FIG. 3. Leprosy bacilli. (Lehmann and Neumann's Atlas.) FIG. 4. Influenza bacilli. (Lehmann and Neumann's Atlas.) FIG. 5. Spirilla of relapsing fever. (Lehmann and Neumann's Atlas.) FIG. 6. Pneumo bacilli. (Lehmann and Neumann's Atlas.) PLATE VA. Bacteria, cocci and amoeba primarily pathogenic for man. FIG. 7. Pneumo cocci. (Lehmann and Neumann's Atlas.) FIG. 8. Cocci of Malta fever. (Lehmann and Neumann's Atlas.) FIG. 9. Amoeba of dysentery. (Lehmann and Neumann's Atlas.) FIG. 10. Bacteria of dysentery. (Lehmann and Neumann's Atlas.) FIG. ii. Gonococci. (Lehmann and Neumann's Atlas.) FIG. 12. Parasite of tertian fever. (Lehmann and Neumann's Atlas.) INTERNAL DISEASES 395 acute rheumatism, pneumococci, meningococci and streptococci occur as well as staphylococci, while some observers describe a micrococcus rheumaticus as the precise causal agent of acute rheumatism. Besides man, cows, and less frequently, dogs, goats, pigs and horses, may be spontaneously attacked. Septic and pyaemic arthritis are frequently seen in calves and foals. Experimentally, the usual laboratory animals are all susceptible. Meningitis, which has recently again become epidemic, is due, like acute rheumatism, not merely to one micro-organism, but to many. Recent investigations point to the meningococcus and the pneumococcus as the most frequent cause of meningitis in man, horses, sheep, cattle, goats and dogs. Naturally occurring cases are usually produced by the meningococcus, but, curiously enough, mice and guinea-pigs do not die under experimental conditions unless this organism is injected into the peritoneal cavity, and other animals appear to be quite insusceptible (Marx). Dysentery is among the diseases the pathological appearances of which may be produced by more than one micro-organism. The amoeba discovered by Losch and a bacillus may both produce this disease (Plate V., figs. 9 and 10). Dysentery is a disease peculiar to man, spontaneous cases not having hitherto been observed in animals ; it is only after the injection of very large quantities of amoebae, or bacilli, that the characteristic lesions can be produced in the large intestine of cats, rabbits, guinea-pigs and mice. Venereal diseases are also peculiar to man. No spontaneous cases of gonorrhoea, soft sores or lues have been observed in animals. Experimental inoculation of cultures of gonococcus in animals produces suppuration in the mucous membranes but no true gonorrhoea (Plate V., fig. n). In 1902 Marx declared that all attempts at inoculating lues into animals (even monkeys) had ended in failure. Since then, however, other results have been obtained. At the fifth International Congress of Dermato- logy in 1904 Van Niessen mentioned pure cultures with which he stated that he had produced symptoms analogous to those of human syphilis in monkeys, pigs and horses.1 Quite recently 1 Confirmed by Finger und Landsteiner, " Untersuch. ueber die Syphilis der Affen," Akad. d. Wissensch. in Wien, 14, 1905. 396 THE HUMAN SPECIES John Siegel of Berlin, who regards syphilis as closely allied to the acute exanthemata, found a microscopic protozoon belong- ing to the flagellates which he considered as the exciting cause ; he traced its development from the early stages by means of a special culture medium of the blood of syphilitic men and rabbits ; and finally he produced iritis and other syphilitic lesions in other animals, although he admitted that all previous cultural experiments had failed.1 Metchnikoff and others have now established the transmissi- bility of syphilis to apes by means of dermal inoculations, and a blood reaction for syphilis has been worked out by Wasser- man. These results may prove of great importance for the prophylaxis of the disease in man. The biology of the acute exanthemata is still very obscure, and will require much more laborious investigation for their elucidation. According to references in the earlier literature collected by M. Schmidt, monkeys as well as man can be primarily infected with small-pox. Thus, in ah epidemic of small-pox in Trinidad (1858), the wild monkeys were attacked, and in the year 1841 a traveller in a forest on the way to David (Chiriqui) saw monkeys suffering from small-pox which four or five days later broke out in David. Except for these isolated reports, small-pox has always been regarded as a purely human disease. Since, however, it has been recently shown that small-pox can indubitably be conveyed to calves, and vaccine pustules be produced in man by inoculation from this material, the identity of cow-pox and small-pox seems fully established. The remaining acute exanthemata, namely, measles, rubeola, chicken-pox and typhus fever, are absolutely specific for man, all attempts at infecting animals having produced negative results. Human typhus is not identical with the petechial fever in horses and cattle. For none of these four very elusive diseases has any causal organism been found, although certain protozoon-like forms have been observed in small-pox, and their connection with the disease more or less established. 1 Apparently the Spirochaete pallida (a species of protozoon) discovered by Schaudinn and described as the specific cause of syphilis is only a modified form of the round protozoon described by Siegel. Siegel, J., " Untersuch. iiber die Aetiologie der Pocken, und der Syphilis," Med. Klinik, 1905, No. 18, p. 446. INTERNAL DISEASES 397 Scarlet fever, which has always been regarded as peculiar to man, appears from the observations of Siegel, previously referred to, to be an exception. He describes a protozoon similar to that of syphilis as the exciting cause of the disease. Diseases which are originally confined to animals, but which may easily be transferred to man, are anthrax, glanders, rabies and foot-and-mouth disease, which must be included among the acute exanthemata. Anthrax, the spore-bearing bacillus of which was described by Koch, is communicated to man partly by the blood of in- fected animals being inoculated through cracks in the skin, and partly by inhaling the dried bacilli and spores with the dust from hides and wool. Symptomatic anthrax, which occurs in cattle, sheep, goats, and occasionally in horses and pigs, is not identical with true anthrax. Glanders is caused by the bacillus Mallei (Loffler) and occurs primarily in horses, donkeys and goats. It is very infectious for man, and also experimentally for guinea-pigs, cats, hedgehogs, rabbits and field mice. The cause of rabies has not yet been isolated ; it is primarily seen in wolves, foxes and dogs, though man and all domestic animals may be secondarily infected, nearly always directly through a bite. Foot-and-mouth disease is transmitted from cattle not only to sheep, horses, pigs, cats, goats and dogs, but also to man, frequently through the use of milk from an infected cow. Siegel states that the exciting cause is a protozoon. A peculiar disease, hitherto only observed in parrots in captivity, though occasionally transmitted to man, is that known as psittacosis. The birds are attacked with diarrhoea, become extremely weak and somnolent, and die after a short time. Nocard found a special bacillus as the cause of this disease. In the years 1892-97 there were seventy cases in man recorded, and since then two others have occurred, namely, those of the owner of a sick parrot, who died with symptoms of a severe broncho-pneumonia, the bacillus of Nocard being recognised by the serum test. His wife succumbed to a similar attack. Finally, actinomycosis in cattle must be noted as an animal 398 THE HUiMAN SPECIES disease. Since Israel's communications in 1878 it has been known that this disease is caused by a ray fungus (Actinomyces bovis), and that it is not infrequently communicated to man, especially to agricultural labourers whose teeth are carious. The grains of corn in which the fungus is contained become lodged between the teeth. The skin, both in man and in cattle, becomes undermined and there is a spreading suppura- tion. The power of producing suppuration and abscesses is also possessed by another streptothrix, that producing the Madura- foot, and also by the streptothrix of Eppinger, which, however, also produces in rabbits and guinea-pigs secondary multiple abscesses and suppuration in the bronchial and supraclavicular glands. The three forms of malaria (Tertian, Quartan and Autumno- ^Estival) represent a disease conveyed by mosquitoes, which is characterised by the destruction of the red blood cells and is only of importance in man (Plate V., fig. 12). Primary dis- ease in mammals, such as proves fatal to man, has not been observed, although certain other animals are stung by the female Anopheles. Secondary infection from man to other animals is ineffective according to R. Koch. On the other hand, according to Friedberger and Frohner, cattle, horses and dogs suffer from diseases similar to malaria both in Africa and Italy.1 No microscopical researches have as yet been published on this point Possibly these diseases \vhich resemble malaria are identical with the dog's disease described by Dr. Sigmund Taussig in Herzegovina, as endemic gastric catarrh accom- panied by fever.2 According to more recent reports (C. Steiner) this disease is a local mosquito fever, from which many persons and also domestic animals of all kinds suffer during the summer months. It is set up by the sting of a mosquito (Culex pipiens).3 The Trypanosoma Ugandense (Castellani) is the asexual generation of a flagellate protozoon ; it reaches the blood of the negro (and also as- has recently been shown of the European) 1 Friedberger und Frohner, loc. cit., ii., p. 7*2. 2 Taussig, Wiener Klin. Wochenschr., 1905, 6 and 7. 3 Steiner, Wiener Klin. Rundschau, 18, 65. INTERNAL DISEASES 399 through the sting of the tsetse fly (Glossina palpalis) ; there it undergoes a change and multiplies, setting up the fatal " sleeping sickness ". In monkeys which have been secondarily infected with the blood or cerebro-spinal fluid of these patients, the disease takes the same course. Dogs and rats are only infected with difficulty ; donkeys, oxen, goats, sheep and guinea-pigs have so far appeared insusceptible. Another kind of tsetse fly (Gossina morsitans) stings horses and cattle, infects them with the Trypanosoma Brucei, and thus produces the dreaded Nagana, which has never been communi- cated to man. It is analogous to the Surra of India and the Mai de Caderas of South America. Since the bacillus icteroides described by Sanarelli in 1897 has ceased to be regarded as the cause of yellow fever, evidence has accumulated to show that this disease is due to the sting of a mosquito (Stegomya fasciata) whereby an incredibly small protozoon is introduced into the body. The death of Walter Meyers was attributed in England to his having been stung by mosquitoes which had settled on yellow fever patients ; and more recent researches have confirmed the correctness of this view. Yellow fever has always been regarded as a disease only occur- ring in man, but according to Friedberger and Frohner horses and dogs are also attacked.1 At the close of this chapter on the infectious diseases, malignant new growths, carcinoma and sarcoma may also be mentioned, as a number of investigators in all countries (e.g.> v. Leyden) take the view that they are caused by a parasitic inoculation and by the growth of an infective agent. We can- not here enter into the pros and cons of this view ; still less can we describe the numerous cancer parasites discovered by various investigators. For our present purpose it is enough to state that dogs, horses, cattle, mice, and even salt-water fishes, are subject to malignant new growths, as well as man ; that the tendency towards it at any rate is hereditary, and that it is possible to inoculate an animal with cancer, or to transplant it from one animal to another of the same species. As we have seen, a large series of infectious diseases are peculiar to man, and are only primarily seen in him, namely, 1 Friedberger und Frohner, loc. cit., ii., p. 737. 400 THE HUMAN SPECIES cholera, enteric, leprosy, influenza, whooping cough, relapsing fever, inflammation of the lungs, dysentery, gonorrhoea, soft sore, lues, measles, rubeola, chicken-pox, typhus, scarlet fever, Madura-foot, Malta fever, the various forms of malaria and sleeping sickness. All other infectious diseases are common to man and animals, or the latter are altogether immune. Man, on the other hand, is immune to certain animal infections, e.g., swine erysipelas, swine fever, rinderpest, fowl, cholera, etc. Between the different races of men there exists a consider- able difference in relative, or absolute, immunity against certain infections. No race is immune to cholera ; it is most fatal among negroes. In the same way enteric, bubonic plague, tuberculosis and diphtheria attack all men alike. The Malagese, the South African negro races, and also the inhabitants of Iceland and Greenland are almost entirely immune to syphilis. Only negroes and Mongolians possess an immunity against yellow fever; negroes lose their immunity little by little from child- hood upwards, if, after a journey into the north of the United States, they return into the yellow fever zone. No race is immune against the acute exanthemata ; negroes are most sensitive to small-pox. Finally, if cancer is to be included among the infectious diseases, we must conclude that in Tunis and Abyssinia, where it is less known, that the people are completely immune to it, and that this immunity is passed on from one generation to another. The general question of immunity, its hereditary transmis- sion, and the part it plays in the life-histories of men and animals, has been very clearly dealt with by Grober.1 The great change in the intensity of contagious diseases, their gradual loss of viru- lence, and often their complete extinction, is a phenomenon which may be explained from various points of view. Bacteri- ologists are inclined to attribute it to loss of virulence in the exciting cause ; clinicians think either that the sensitive indi- viduals may have died out, or assume a congenital or acquired immunity for the survivors, as for example, with plague, cholera and influenza. The occurrence of immunity is attri- 1 J. Grober, "Die Vererbung der Immunitat," Med. Klinik, 1905, 18, p. 429. INTERNAL DISEASES 401 buted by Metchnikoff mainly to the leucocytes, which in all human and animal bodies act as sentinels and destroy any harmful matter which invades them. Buchner talks of alex- ines, and many other writers of various specific " anti-bodies ". All, however, agree that there are two sorts of immunity, (i) an active immunity acquired after passing through an attack of the disease, and (2) a passive immunity gained by the transference of the active and acquired protective substance to a second and previously healthy body, in order to guard it against some definite disease. Obviously, hereditary immunity can only be passive ; according to Ehrlich the transmission of the protec- tive substance does not take place either in the ovum or sper- matozoon, but only by means of the placenta and the milk of the mother. He does not consider that either of these methods of transmission clearly indicate a definitely hereditary immunity. As, however, the question of acquired immunity is not finally settled, Grober thinks it probable that certain variations are present in the germ cells which lead to the development of special powers or tendencies. ($) Non- Infectious Diseases. Diseases due to animal parasites naturally come next to the infectious, for parasitic animals maintain their existence at the expense of the human organism, and partially secrete poisonous substances, such as occur in the infectious diseases. The differ- ence is that the parasite produces local more than general disease. Internal Parasites. — Of parasitic nematodes only the follow- ing are peculiar to man : — Oxyuris vermicularis (Plate VI., fig. i) ; Trichocephalus dispar (Plate VI., fig. 2) ; the rare Filaria labialis of Pane (Plate VI., fig. 3); and the Filaria bronchialis (Plate VI., fig. 4); the Filaria loa of Guyot, which lives beneath the conjunctiva of the negroes on the Congo and Gabon ; the Filaria lentis of Dies, which is sometimes found in lenses after removal (Plate VI., fig. 5) ; the Filaria sanguinis hominis, found in its embryonic condition in large numbers in the blood of man in the tropics of both the Old and New World (Plate VI., fig. 6), and two tiny varieties of Anquillula (A. stercoralis and A. intestinalis) found respectively in Cochin China and Italy. 26 402 THE HUMAN SPECIES The trematodes peculiar to man include the Distomum rathouisi. perhaps identical with D. crassum (Plate VII., fig. 7) ; the Distomum heterophyes, a rare suction-worm in Eastern Asia, once seen by v. Siebold in Egypt (Plate VII., fig. i), and the Distomum ophthalmobium Dies once observed in the capsule of the lens of a child (Plate VII., fig. 2). Tapeworms which inhabit man only in their adult form are Taenia saginata (mediocanellata), the tapeworm of diseased beef (Plate VII., fig. 3); the Taenia solium, from measly pork (Plate VII., fig. 4); the Taenia nana, found by Bilharz in Egypt (Plate VII., fig. 5); the Taenia flavopunctata, first dis- covered in America by Weinland (Plate VII., fig. 6), and the Taenia madagascarensis of Davaine. Intestinal worms parasitic in various animals as well as in man are Ascaris lumbricoides ; the common round worm which also infests the gorilla is common to all the races on earth ; Ascaris mystax, commoner in dogs and cats, is also found in man ; Trichina spiralis is found in men, swine, rats, mice, cats, martins and foxes. The Filaria medinensis occurs in man, dogs and horses in all the tropical regions of the Old World. Eu- strongylus gigas occurs in man, dogs and horses ; the small Strongylus duodenalis, which produces extreme ansemia in man, is also parasitic in the gorilla ; Strongylus longevaginatus has been frequently observed in animals and seldom in man, and finally the Echinorhynchus hominis, which is usually parasitic in the larva of insects, has on a few occasions been found in man. Flukes living in man and various animals are Distoma hepa- ticum and Distoma lanceolatum ; neither of these are peculiar to man but are more frequently found in sheep, cattle, rodents, pachyderms and marsupials ; Distoma spathulatum occurs in man and cats in Eastern Asia ; Distoma conjunctum occurs in man and in the liver of pariah dogs in India and Eastern Asia ; Distoma pulmonale occurs in the lungs of men and of tigers in Eastern Asia. Tapeworms are parasitic in man and in various animals. The eggs of Taenia cucumerina are transferred from the dog to the dog-louse, and thence into the bodies of those who keep dogs. Taenia echinococcus occurs in man, dogs, swine and herbivorous animals; Bothriocephalus latus, which is transferred from pike PLATE VI. Specific internal parasites of man. FIG. 2. Trichocephalus dispar. a, male, with the anterior part lying beneath the mucous membrane ; b, female. (Leuckart, Parasiten.) FIG. i. Oxyuris vermi- cularis. (Five times enlarged.) a, male ; b, female. (Leuckart, Parasiten.) FIG. 3. Filaria labialis. (Enlarged.) (Leuckart, Parasiten.) FIG. 5. Filaria lends. (About 35 times enlarged.) (Ammon.) FIG. 4. Filaria bronchialis. (Treutler.) PLATE VIA. Specific internal parasites of man. FIG. 6. Filaria sanguinis hominis. (Lewis.) (Leuckart, Parasiten.) FIG. 7. Cercomonas from the liver. (After Lambl.) FIG. 8. Trichomonas intestmalis. (Zunker.) FIG. 9. Amoeba coli in intestinal mucus. (After Losch.) (Leuckart, Parasiten.) PLATE VII. Specific internal parasites of man. FIG. 4. (Enlarged.) Head of Taenia solium. (Leuckart, Parasiten.) FIG. 6. Taenia flavopunctata. (Wemld.) (Leuckart, Parasilen.) FIG. 7. Distomum Rathouiti. (Leuckart, Parasiten.} FIG. i. Distomum heterophyes. (v. Siebold.) ~-^^u FIG. 3. (Natural size.) Taania saginata. (Leuckart, Parasiten.) FIG. 2. Distomum ophthalmicum. (Ammon.) a, contracted; b, extended. (Leuckart, Parasiten.) FIG. 8. (Enlarged.) Balantidium coli. In different stages of division. (Leuckart, Parasiten.) FIG. 5. Taenia nana (18 times enlarged). (Leuckart, Parasitcii.) INTERNAL DISEASES 403 to man, dogs and cats; Bothriocephalus cristatus, which is seldom found in man, and is commonest in dogs in Northern Greenland. Besides these worms, certain unicellular organisms are not infrequently observed as internal parasites in man. Thus among the Infusoria, Cercomonas intestinalis is found in the intestine in cases of cholera and diarrhcea (Plate VI., fig. 7); Trichomonas intestinalis in acute and chronic diarrhcea and also in typhoid (Plate VI., fig. 8); Balantidium coli in severe chronic affections of the intestine (Plate VII., fig. 8) ; Coccidium oviforme, a sporozoon, is often transferred to man from rodents, such as mice and rabbits. Amceba (A. coli) has been recog- nised by Lo'sch in the large intestine in men suffering from dysentery. Very few external parasites are peculiar to man ; the flea, Pulex irritans (Fig. 201) ; the head-louse, Pediculus capitis (Fig. FIG. 202. FIG. 203. FIG. 204. Human head-louse. Crab-louse. Bed bug. 202), found, according to Darwin, on various races in different parts of the world ; the clothes-louse, Pediculus vestimentorum ; the crab-louse, Pediculus pubis (Fig. 203) ; and the bed bug, Cimex lectuarius (Fig. 204). Many other sorts of fleas may be transferred to man from dogs, cats, etc, but they soon leave his body. Parasites not peculiar to man but found also upon other animals are the sand flea, Pulex penetrans, the Sarcoptes or Acarus scabiei (causing itch), which according to Ziegler also lives on horses and some sorts of sheep ; the Macrogaster folliculorum, which is parasitic on the skin of man and of various animals (dogs, cats, swine, cattle and goats) ; and the sheep tick, Ixodes ricinus, which occasionally occurs as an unwelcome parasite on man, though common on dogs, cattle, sheep and wild animals. Among vegetable parasites only three are undoubtedly 26 * 404 THE HUMAN SPECIES peculiar to man, namely, the fungus of Pityriasis (tinea) versi- color, Microsporon furfur, the fungus of thrush, Oi'dium (or Sac- charomyces) albicans, and the fungus which is parasitic in gastric mucus, Sarcina ventriculi (Figs. 205, 206, 207). The remainder occur also in animals, such as Microsporon Audouini (ringworm), Achorion Schonleini (favus), and the fungus of Tinea circinata, which is common to man, dogs and cats ; and Trichophyton tonsurans, which produces the char- acteristic ringworm among men, cattle, dogs, horses, goats and cats. Intoxications. Seeing that there is a general physiological similarity between man and the remaining red-blooded animals, and FIG. 205. Micro- sporon furfur. FIG. 206. Oi'dium albicans. especially with those which are warm blooded, it may very naturally be assumed that the poisons which are dangerous to man will also damage all Vertebrates, and to a greater degree the higher they stand in the zoological scale. Gradually acquired or inherited immunity may cause exceptions to this general rule. Reports on the action of various poisons are nearly all with reference to domestic animals, as for obvious reasons observations on wild animals are very few and far between. As regards the former class, Friedberger and Frohner l have demonstrated their complete correspondence with man in the sphere of toxicology. Among corrosive poisons, which act upon the skin and still 1 Friedberger und Frohner, op. cit., Bd. i., p. 240. INTERNAL DISEASES 405 more on the mucous membranes of man and other animals, the most important are the caustic alkalis (potash, soda, lime and ammonia), and the acids (oxalic, sulphuric, nitric and hydro- chloric acids). Next come the poisonous metals, zinc, antimony, chromium, cobalt, copper and mercury with their salts, and the metalloids, iodine, phosphorus and arsenic. Among plants with an irritant action on the stomach and intestinal canal may be enumerated the following, which are among the most powerful of those indigenous in our soil : the autumn saffron, the spurge laurel, the yew, various kinds of spurge, the labur- num, the ranunculus, the larkspur, the aconite, and the poison- ous fungi, etc. A sharp local inflammation, accompanied by severe general symptoms, are produced by poisons found in the bodies of certain kinds of melolonthae and the Spanish fly ; here, too, may be classified the poison of the scorpions, the millepedes and the poisonous spiders. The poison discharged from the skin of the salamander, if taken internally, acts as an irritant, and even may prove fatal to small animals like dogs. The same thing occurs when concentrated formic acid is ejected from the poisons of wasps, hornets and bees in large quantities into men or animals. The poison leads not only to painful local symptoms, but to marked general intoxication. Narcotic poisons, causing congestion of the brain, spinal cord, heart and lungs, are present in the poppy, deadly-night- shade, the black henbane, the honeysuckle, the thorn apple, tobacco, the red foxglove, the variegated hemlock, the water hemlock, cow-parsley, the darnel, the broom, the ergot, and in a less degree the chick pea, the edible pea, and the leaves of the potato. An extremely powerful poison is that obtained from St. Ignatius' bean — strychnine. Here, too, may be mentioned prussic acid and the cyanides, alcohol and various gases, such as carbon dioxide and monoxide, ordinary coal gas, ammonia vapour, and sulphuretted hydrogen. All these narcotic poisons, when introduced in certain quantities, produce the same symp- toms in animals as they do in man. An equally close similarity of effect exists with regard to the haemolytic snake poisons, though there are remarkable ex- ceptions in the case of certain animals. Generally speaking, 4o6 THE HUMAN SPECIES the smaller the body of the man or animal, and the fuller the poison sac has become through a prolonged period of activity, the sooner does a fatal result take place. From the earliest times exceptions have been known to the general rule — cases in which men and animals were immune to animal poisons, and in which animals had become immune to vegetable poisons.1 In the old authors (yElianus, Hist. Anim., lib. i., cap. 57; Celsus, v., 27; Plin., Nat. Hist., vii., 2, etc.; Lucan, ix., v., 95 et sqq^) there is an account of a race, the Psylli, in Lybia, who were absolutely immune to snake bites. Pliny mentions another race, the Ophiogenes on the Helles- pont, who were similarly immune, and moreover had the power of healing those who had been bitten by snakes, by means of their saliva. The hedgehog is one of the animals possessing natural immunity to poisons. The naturalist Lenz states he has ob- served that the hedgehog is not affected by the bite of an adder, and can devour Spanish flies with the keenest appetite, and without coming to any harm : Brehm has confirmed this ob- servation, and also mentions the Iltis and Mongoose (Herpestes javanicus) as champions who can receive many bites in their contests with snakes without being poisoned. The wasp buz- zard (Pernis apivorus) is quite insensitive to the stings of wasps and bees, and so is the Edolius paradiseus, and the bee eater, Merops apiaster. The Batrachians react very variously to wasp and bee stings. While the ordinary pond frog avoids both bees and wasps, the grass frog is immune against bees but not against wasps ; the toad, on the other hand, devours both with avidity and without damage to itself. (y) Diseases of Special Organs. Most of the material available for a comparison between the internal diseases of man and animals is derived from the observa- tions of veterinary suigeons upon domestic animals either during life or after death ; for such diseases in wild animals can only occasionally be observed among the inhabitants of our zoological gardens. In this class of disease also we may note a far-reaching agreement between animals and man, dependent on the general 1 Hopf, L., Immunitdt und Immniiisiening. Tubingen, 1902, pp. 1-4. INTERNAL DISEASES 407 similarity in the anatomical construction of man and the class of Vertebrates now under consideration. Diseases of the Digestive Organs. — A glance through the veterinary text-books on special pathology, or through the mortality lists of the zoological gardens, reveals the same features, both in pathology and pathological anatomy, as may be seen in man. The mucous membrane of the mouth is subject to the same lesions both in man and in animals. Among the herbivora (horses, cattle, sheep) we find the same catarrhal and aphthous stomatitis, and in cats and dogs, and also in horses and cattle the same ulcerative processes as occur in the mouth of man. Mumps (an inflammation of the parotid gland of variable character) is not peculiar to man, but also occurs in dogs, cats, horses, cattle and goats. Suppurative parotitis has been observed in a leopard, and noma has been met with several times in apes (M. Schmidt). Actinomycosis of the parotid occurs in cattle, and sore throats similar to those seen in man may occasionally, but not commonly, be observed in horses and cattle. Diverticula and enlargements of the gullet are now and then observed in cattle ; stenosis, lacerations, inflammation, par- alysis and spasm are much more frequently seen in all domestic animals. The descriptions of diseases of the stomach (acute and chronic catarrh) in horses, cattle, apes and beasts of prey, and of catarrh of the intestinal canal in apes, dogs, cats and pigs, might be taken straight from a work on human pathology or pathological anatomy. Horses, cattle, dogs and swine suffer from colic as do men ; cattle suffer from ulceration of the stomach and intestines, and these and other domestic animals, and also wild cats, foxes and wolves, also suffer frequently from haemorrhage from the stomach and intestines, and from inflammatory conditions due to various causes but not differing materially from those found in man. Schmidt has had the opportunity of observing an intussusception of the caecum into the colon in a monkey, and in another a prolapse of the rectum. To pass on to the diseases of the liver, catarrhal jaundice is frequently observed in dogs, hypertrophy and fatty liver in apes, parenchymatous inflammation and abscess in various domestic animals, acute yellow atrophy in sheep and horses, cirrhosis (not 4o8 THE HUMAN SPECIES due to alcohol !) in horses, dogs, cats, cattle and swine, and cancer in dogs, horses and cattle. In all these conditions there is a complete similarity between animals and man. The sole point in which man differs from other animals is that he suffers occasionally from movable liver. All domestic animals, as well as the apes and smaller beasts of prey in menageries, like man suffer from acute peritonitis which frequently becomes chronic, and is due to both internal and external causes. These animals may also develop ascites as the result of disease of the liver, spleen, heart or lungs. Diseases of the Organs of Respiration. — Horses, sheep, cattle, swine, dogs and cats may suffer from acute nasal catarrh which often becomes chronic. Epistaxis occurs in horses, especially after severe exertion, and tumours of all sorts, from mucous polypi to sarcoma and carcinoma, all frequent pathological find - ings in most of our domestic animals. Dogs and horses, in which the organs of respiration are so important, are subject to acute and chronic laryngitis. CEdema of the glottis, a condition once observed in a jaguar by Schmidt, often occurs in horses. Acute and chronic bronchitis are fre- quently seen both in domestic animals (such as horses, dogs, cattle and sheep) and in apes and the smaller felidae and canidae in zoological gardens (M. Schmidt). Horses, cattle, sheep, swine, dogs and cats frequently suffer from catarrhal and in- terstitial pneumonia. Both in men and animals inflammation of the lungs may go on to gangrene. Haemorrhage and em- physema are very common in horses and cattle. Inflammation of the pleura with or without effusion into the pleural cavity, has the same etiology and course in animals as in man. The acute cases in apes, and in beasts of prey, are usually complications of pneumonia ; the chronic cases in apes, dogs, sheep and horses end in chronic pulmonary disease, chiefly tuberculosis. Hydrothorax may occur in horses, cattle, dogs and other animals owing to dropsy, and pneumothorax owing to other causes. Diseases of the Circulatory Organs. — Inflammation of the pericardium, so frequently seen in man, is only common in domestic cattle. It is sometimes found post-mortem as the re- sult of a tuberculous pleurisy in apes, and in the larger and INTERNAL DISEASES 409 smaller beasts of prey (Schmidt). Inflammation of the heart muscle, observed by Schmidt in tuberculous apes, is otherwise only seen in horses and cattle ; this is also the case with acute endocarditis, which is rare in dogs, swine and other domestic animals. As in man, the nature of the lesion causes the acute endocarditis frequently to become chronic, setting up valvular defects ; and on this again depends the final hypertrophy and dilatation of the heart which ensues. Concentric hypertrophy was seldom found by Schmidt in apes ; excentric hypertrophy he found much commoner both in apes and in beasts of prey. Horses suffer from hypertrophy and dilatation, owing to the special demand for efficiency which is made upon their hearts ; they share also with men the peculiarity of developing aortic aneurysms (though Schmidt found an aneurysm of the thoracic aorta in Cercopithecus pluto) ; cattle as well as horses may suffer from thrombosis with consequent gangrene or haemorrhage. If the spleen, owing to its blood-forming function, is con- sidered as an annex to the circulatory system, we may here mention the acute enlargements which may occur in cattle and pigs, as in man, as the result of cirrhosis of the liver and portal obstruction. On the other hand, the chronic enlargement associated with malaria and leuchaemia is peculiar to man. So is the rarer condition known as wandering, or movable, spleen ; this, like the movable liver and kidneys, is apparently the result of the upright position. Inflammation and abscess of the spleen, which are not infre- quent in animals as the result of injuries, are among the rarest of pathological conditions in man. Diseases of the Urogenital Organs. — Here, again, we find general consonance with the corresponding pathological pro- cesses in man. Acute (diffuse) inflammation of the kidney is a frequent disease in all domestic animals, such as horses, cattle and dogs; chronic (parenchymatous) inflammation, correspond- ing to Bright's disease in man, attacks cattle and horses, but rarely beasts of prey ; in the latter, contusions and other trau- matic lesions not infrequently set up inflammation of the capsule or pelvis of the kidney, and thus lead to interstitial nephritis, and the large accumulations of pus called pyonephrosis. 4io THE HUMAN SPECIES Schmidt observed that fatty degeneration of the kidneys has been found in a wolf, and atrophy of the kidney in a macaque (Inuus cynomolgus). Inflammations of the pelvis of the kidney going on to sup- puration (pyelitis) are usually caused, as in man, by the irritation of a calculus, or retained urine (dogs, horses, cattle). Movable kidney, which is much more frequent, especially in women, than movable liver or spleen, does not appear to have ever been observed in animals ; at any rate I have found no note of the condition in the literature. Haematuria, which is especially common among ruminants, depends on disease either in the kidneys or bladder. Catarrh of the bladder in horses, cattle and dogs results usually from retention of urine, which may be due to a calculus, or to stenosis of the urinary passage at any point. Diseases of the genital organs mainly fall within the domain of surgery (hypertrophy of the prostate, phimosis and para- phimosis). Among internal diseases may be placed catarrh of the vagina and the mucous membrane of the uterus, while puer- peral fever, from which female domestic animals and those kept in zoological gardens frequently suffer, must be included among the infectious diseases. Diseases of the Organs of Locomotion. — Acute articular rheumatism has been already mentioned among the infectious, the greater number of the remaining diseases of the organs of locomotion are considered under surgical diseases. Only a few, therefore, remain for discussion in this place. Among idiopathic diseases of the muscles, muscular rheuma- tism, which occurs in horses, dogs and cattle, and less frequently in sheep and swine, is etiologically closely related to the disease as seen in man. Further analogies are found in certain bone diseases which only come under the care of the surgeon when considerable de- formity or destruction of the bone has occurred. Rickets, a disease of infancy, which is said to begin frequently in fcetal life, consists in alterations in the growth of the bones, due to inflam- mation and to delayed ossification ; it affects not only the long bones, but also the bones of the pelvis, spinal column, ribs and skull. Young dogs and pigs especially suffer from the lesions INTERNAL DISEASES 411 which are characteristic of the disease in human children, namely, enlargement of the ends of the bones, bending of the bones, deformity of the spine, etc. Foals and calves are simi- larly affected, and the condition is met with also in artificially fed young beasts in zoological gardens. According to A. Hirsch, rickets is not seen as a disease of children either in Madagascar, Mayotte, or the Archipelago adjacent to these islands. Ebbell, however, states that he has frequently seen the disease during his ten years' stay in Madagascar. A disease of the bones which is limited to adult life is osteomalacia, in which a softening of the bony skeleton takes place owing to the abnormal absorption of lime salts, and the replacement of the firm osseous tissues by bone marrow. This disease both in man and animals is limited to the female sex, and generally comes on during pregnancy or after childbirth. It is most frequently seen in cattle, less often in sheep, goats and swine, and least often in mares and bitches. Besides rickets and osteomalacia there is a third disease of the bones which occurs both in man and in animals, namely, osteoporosis. Here there is atrophy due to absorption of the bony substance. In man this is often a symptom of senility, but under the influence of certain lesions it may occur earlier. It has not yet been observed among wild animals, but it occurs in domestic animals, especially cattle, as the result of insufficient food, and also in animals in captivity in zoological gardens, either as a result of insufficient food or exercise. The so-called giraffe's disease described by Brugsch l may be classed as osteoporosis ; and on this condition depend the frequent spontaneous fractures which occur in zoological gardens among cassowaries, herons, etc., in captivity, when they are handled. Diseases of the Nervous System. The gross pathological, and anatomical, changes which take place in the brain and spinal cord are the same in domestic animals as in man. From various causes horses, dogs and sheep may suffer from hyperaemia or anaemia of the brain ; chronic hydrocephalus and actual apoplexy may occur in horses, 1 Zoolog. Garten, 1864, no. 5, p. 129. 412 THE HUMAN SPECIES cattle, sheep and swine, and Schmidt has recognised the same conditions in various beasts of prey. Meningitis is not infre- quent in apes, horses, cattle, dogs, swine, sheep and goats, and in all animals tumours of the brain may be found similar to those in man. Swine, sheep, cattle and horses when running close together in herds, or when packed in carts, may suffer from sunstroke or heatstroke, especially the latter. Cases of bulbar paralysis, with the same progressive and fatal course as in man, and the same pathological findings (atrophy of the bul- bar nerve roots), have been noted in horses. Horses and dogs are especially liable to inflammation of the spinal cord and its membranes, generally in a chronic form. Sarcoma, glioma, myxoma and other neoplasms of the cord may be diagnosed during life in various domestic animals. Peripheral nerve palsies occur in various domestic animals, and have the same causation as in man, namely, pressure, at- mospheric influences and infectious diseases. Single or double facial paralysis is frequent in horses, rarer in cattle and dogs. Single or double paralysis of the hypoglossal nerve is frequent in horses and dogs ; paralysis of the masseters and temporal muscles, due to lesions of the third (motor) division of the fifth, is not unusual in dogs and cats, but is less common in horses and cattle. Horses may suffer from paralysis of the pharynx and gullet due to disease of the ninth and tenth cranial nerves ; unilateral laryngeal paralysis in horses depends on lesions of the recurrent laryngeal branch of the vagus ; paralysis of the sphincter muscle of the bladder in dogs depends on disease of the centre lying in the upper part of the fifth lumbar segment of the cord. Muscular paralysis in the upper extremities in man, conse- quent on lesions of certain motor nerves, occurs in exactly the same way in animals. Paralysis of the shoulder-blade muscles in horses and cattle is caused by disease of the nerves arising from the cervical plexus (suprascapular nerves) ; lesions of the brachial plexus in horses and dogs cause paralysis of all the motor nerves arising from it, among which the paralysis of the radial nerve is especially met with in horses and cows. Par- alysis, complete or partial, of the posterior extremities in cattle, INTERNAL DISEASES 413 horses and dogs is due, as in man, to acute or chronic patho- logical changes in the spinal cord above the paralysed part. Schmidt has noted such total, or partial, paralysis in apes, canines, and other beasts of prey in zoological gardens. Paralysis of certain sensory nerves in the lower extremity is very rare, and only seen in horses and large dogs. The nerves most frequently involved are those supplying the thigh and shin and calf. Still less frequent is paralysis of the two mixed nerves — the crural and obturator. Pathological irritation of sensory nerves (neuralgia) is probably similar in animals and man, but is difficult to diag- nose. Pathological irritation of motor nerves (spasm) is most clearly seen in the so-called springhalt in horses : it is probably due to a painful sciatica, and consists of regularly recurring spasms of the posterior thigh muscles. Schmidt notes that muscular spasms accompany certain diseases in apes, and are still more frequent symptoms in beasts of prey. The neuroses seen in men, which manifest themselves in motor disturbances of various kinds, are also reproduced in certain animals. Horses, and according to Schmidt apes and jackals, suffer from epilepsy. Eclampsia is commonest in young dogs and pigs, less frequent in bitches and other grown animals, such as cows ; catalepsy is very seldom seen (prairie wolf, wolf, dogs, horses, cattle). St. Vitus' dance is also observed in young dogs and jackals. Two severe diseases depending on pathological changes in the thyroid gland, especially as regards the suppres- sion or increase of its internal secretion, show the close relation- ship of human to comparative pathology. Cretinism and myxcedema, which depend upon degeneration of the thyroid gland and suppression of its internal secretion, are unknown in aninjals, either in the endemic or sporadic form. Records of well-established cases are available, in which, after complete extirpation of the thyroid, owing to goitre, cachexia strumpriva, similar exactly to that seen in man, was observed. The re- verse of hypothyroidism is hyperthyroidism, which in man gives rise to Graves' disease (proptosis, goitre and severe nervous disturbance of the heart) ; it is not infrequently seen in certain animals (dogs, horses, cattle). Mental Diseases. — Can animals become mentally deranged ? 414 THE HUMAN SPECIES This question is but little discussed in pathological literature. As regards the more highly gifted vertebrates, a partial affirma- tive cannot be denied offhand. If the disturbances set up by morphia and alcohol are to be included in the organic psychoses of man, then we may correctly speak of psychoses in animals due to the ingesta ; thus the swallowing of belladonna, hyoscy- amus, datura strammonium, allium, cannabis and poisonous fungi produces severe disturbances going on to delirium ; Pteris aquilina (bracken) produces unconsciousness ; the administration of melampyrum is followed by depression. Rabies is a remarkable psychosis due to the poisonous action of some infective material on the cerebral cortex, and may be communicated to dogs and other animals by mad wolves and foxes. The clinical picture is well known from cases in man ; it begins with peevishness and anxiety, and goes on to the most violent psychical excitement, with furious delirium and violent convulsions. We must conclude from the behaviour of the rabid animals that similar processes take place in their cerebral cortex. It still remains to ask whether it is possible for a psychosis to develop in animals, with or without recognisable pathological or auatomical changes, quite apart from any poisoning or infection ? I have ransacked the literature in order to obtain some light upon this question, and have only been able to find a reference to it in the work of Lindsay (Journal of Mental Science, July, 1871). He begins by drawing a dis- tinction between " insanity," which is applied to man, and de- notes very various mental disturbances, and " madness," which is applied to animals, and denotes, more or less vaguely, a number of very heterogeneous diseases. He is quite aware that veterin- ary surgeons deny that any parallel exists in the region of psychology between man and animals ; in their view animals have no true intellect, and so cannot lose it ; that is to say, it cannot be damaged by any morbid changes. Lindsay, however, rightly disputes this point of view, and holds that the higher animals, whose intelligence stands so near to that of man, must suffer from similar mental disturbances. Insanity in man and madness in animals convey the same idea to him, and he re- solutely opposes the foolish view held by many other veterinary surgeons that all madness in animals is a kind of hydrophobia, INTERNAL DISEASES 415 but he admits that those psychical disturbances in animals which are not due to hydrophobia manifest a very similar sort of mania. Lindsay describes many cases of acute mania in elephants, horses and dogs. When, at certain times in the year, elephants go mad, and become dangerous to man, their condition may be compared to the " running amok " of the Malayans. Similar acute disturbances occur in horses and dogs. In the latter, all cases of extreme excitement and madness after bites are not due to hydrophobia ; the bites of such dogs are harmless to man. There are no pathological or anatomical findings to explain these conditions — we have to fall back on surmises. When, however, Lindsay, on the authority of Lord Royston, mentions certain psychical disturbances in fish, manifested by their swimming round and round in circles, we can only suppose that these fishes had some parasitic affection in the brain. Actual examples of mania may be seen when cows and mares during the oestrum drag at their chains with rolling eyes and chat- tering teeth, and finally fall down in tetanic convulsions ; or when sows in their madness devour their own young ones. The converse of this nymphomania is the satyriasis of the male animals (stallions, bulls, bucks, stags), and, according to a wide- spread popular opinion, also the male hares. The moderately careful observer will have no difficulty in diagnosing these condi- tions of morbid excitement from the changed and unnatural behaviour of the animals, and will certainly attribute them to the congestion and unusual excitability of the genital organs. Not infrequently a condition of extreme depression is noticed in mares, cattle and swine, accompanied by increasing deficiency of sensation, such as is seen in cases of imbecility in man. This condition, and the corresponding one seen in males, has its pathological and anatomical cause in the effects left on the brain by a previous attack of meningitis. It would, however, be useless to expect to find such a condition in those animals which, after remaining motionless and refusing their food for a few days, die owing to grief at the loss of their liberty, or at separa- tion from a beloved master. During an elephant hunt in Ceylon, Tennant 1 saw a captured elephant, after a violent exhibition of rage, quietly He down and 1 Brehm's Tierleben, Bd. ii., p. 707. 416 THE HUMAN SPECIES die in twelve hours. The story of Stanley's dachshund is well known. When Stanley started for his last great African journey he left the dog behind. The animal from the first refused all nourishment and died after three days. I myself know of a yellow-hooded cockatoo which, two days after its mistress had sold it, was found dead in its cage. These are well-authenti- cated instances of extreme depression of spirits which might well be identified with melancholia in man, were it not for the absence of any evidence of the characteristic psychical incapacity, the hallucinations, delusions, etc., so that we can only conclude that it is a simple physiological and psychological depression. Thus melancholia in man must be regarded as a specific psy- chosis. Lindsay considers it self-evident that it is very difficult for veterinary surgeons, or other observers, to determine the onset and progress of intellectual disturbances in animals owing to their being unable to speak. Now as regards the gradual onset of imbecility as a sequel to acute cerebral processes, the behaviour of the affected animal gives plenty of ground for the establish- ment of the diagnosis ; nor is it easy to pass over the semi- conscious condition which is connected with epilepsy in animals. On the other hand, it would be useless to look for symptoms of insanity (paranoia), hysteria or hypochondria in an animal, for the morbid delusions, which are peculiar to these conditions, can only occur in a brain gifted with higher reasoning powers, such as that of man. (3) Chronic Constitutional Diseases of a Non = Infectious Nature. Among morbid blood changes, such as are seen in man, ordinary anaemia has been observed among young dogs, cats, swine, horses and cattle; pernicious anaemia only in the last- named. Hydraemia attacks sheep, swine and cattle, and leu- chaemia occurs in cattle, horses, cats and swine. Haemophilia has as yet only been noticed in horses ; scorbutus, on the other hand, occurs in swine, dogs and sheep ; Schmidt has seen a case in a gorilla. Horses occasionally suffer from Diabetes insipidus, and dogs, cats, cattle and horses from Diabetes mellitus. Among wild animals in captivity, Schmidt has seen cases of the last-named in two apes and a panther. Other common metabolic diseases, INTERNAL DISEASES 417 such as gout and obesity, in man are not unknown in domestic animals; dogs suffer from the former, and also parrots, when too closely confined and too richly fed. Dogs, cattle and sheep suffer from the latter, and also pigs. Scrofula, frequent in young horses and swine, is, as in man, no definite disease, but a general term denoting a number of morbid symptoms which are due to tuberculosis (Friedberger and Frohner). Finally, there is Addison's disease — a chronic ailment, causing general cachexia and pigmentation of the skin, produced by cancerous, tubercu- lous or other changes in the suprarenals. No notice of this disease has hitherto appeared in veterinary text-books, and for the present therefore it must be regarded as peculiar to man. Diseases of the Skin. — We will conclude the section on in- ternal diseases by considering the diseases of the skin which will form a link with the diseases of a surgical nature. Our dis- cussion of the infectious and parasitic diseases of the skin left for further consideration a series of other pathological conditions of the skin, which partly resemble those affecting man, and partly differ from them. The same atrophy of the skin which leads in old men to the disappearance of the pigment, and also of the hair itself, is also met with in old animals. In animals, too, hypertrophy of the papillae leads to warts and polypi, which are preceded by a hypertrophy of the cutis. On the other hand, Elephantiasis arabum and Ichthyosis, which depend on hyper- trophy of the epidermis, are peculiar to man. The various forms of inflammation of the skin show many points of resemblance between man and animals. Sheep, swine, dogs and horses often suffer from erythema ; cattle, horses, dogs and swine from urticaria ; and these animals, with the excep- tion of swine, also develop pemphigus and acne. Schmidt has reported a case of psoriasis in an orang-utan and in an ape. On the other hand, the well-known text-book of Friedberger and Frohner says nothing about herpes, impetigo, ecthyma or prurigo, so that for the present we must conclude that these conditions are peculiar to man. 27 4i8 THE HUMAN SPECIES . 2. Surgical Diseases. Staphylococci and streptococci play the same part in surgery as they do in internal medicine; and both in man and ani- mals cause inflammation, suppuration and blood changes. M, Schmidt1 has recorded an interesting autopsy on a Nasua solitaria, which died of pyaemia following injury; there were the same changes in the pleura, lungs, heart, kidneys and liver as are found in similar cases in man. Contusions, in man and animals alike, usually run a favour- able course; contused, lacerated and incised wounds take a different course according as they are infected with cocci or not. Surgical skill is able to ward off the damage done by the inflammation and suppuration of wounds in man. Animals when not treated by man unconsciously protect themselves from infection by licking the wound as far as possible. Further investigations must decide whether this merely removes the causes of inflammation mechanically, or whether the saliva has any special healing power. If the healing process is prevented, the character of the wound, such as its depth, etc., will determine the sequel, which may occasionally be abscess formation, and in severe cases gangrene and destruction of the soft parts, or even of the bones. In the following section I shall follow in detail the work of Moller and Frick,2 dealing with the surgery of special organs. Surgery of the Digestive Canal. — In dogs, cattle and horses certain cystic tumours not infrequently occur under the tongue, known as " Ranula," the cause of which, as in man, is obscure. The treatment is the same in all cases. Stenosis of the gullet occurs in horses ; oesophageal diverti- cula are met with in horses and cattle; foreign bodies may be found in all domestic animals, and in wild animals during captivity. The importance of an abdominal wound varies, as in man, according as merely the body-wall or the contained viscera are damaged. If the latter, experience with animals has shown that wounds of the intestine are less dangerous than those of the stomach and liver. Ruminants (sheep and cattle) 1Zoolog. Klinik, i., 2, p. 260. 2 Moller und Frick, Lehrbuch der Spcziellen Chirurgie fur Tierarzte, 3rd. ed. Stuttgart, Enke, 1900. . SURGICAL DISEASES 419 have this peculiarity, namely, that gastrostomy or gastrotomy, which usually give rise to the escape of a considerable amount of gas, run as unfavourable a course as colotomy in horses, where the gas is developed in the large intestine. Perityphlitis, starting from the vermiform appendix of the caecum, only occurs with such disastrous frequency in man. The majority of mammals do not possess an appendix, and there are no pathological or anatomical records concerning in- flammation of the appendix in such animals (anthropoids and certain rodents) as do possess one. Congenital stenosis of the rectum or anus, occurring in dogs and swine, and less often in bulls and horses, is of similar surgical import as in man. Prolapse of the rectum and anus is a frequent occurrence in horses, dogs and other domestic animals. Intussusception, which is so dangerous to man, is equally so to the animals in which it frequently occurs, namely, cattle, horses and dogs. Volvulus of the left colon in horses is equally fatal. Hernia is caused in animals in the same manner as in man. It may be congenital, owing to a widely open umbili- cus or femoral ring, or may be acquired later owing to increased intra-abdominal pressure or subcutaneous injury of the belly- walls by blows from hoofs or horns. Man only differs in one point from animals. It is only in him that the pull of a fatty mass from without can cause a bulging of the peritoneum, and so lead to hernia. Umbilical hernia occurs in horses, cattle and dogs ; inguinal hernia in bitches and the males of other domestic animals; abdominal hernia in horses and cows ; perineal hernia is rare, and is almost entirely confined to dogs, while diaphragmatic hernia is more frequent in horses, and less frequent in dogs, cattle and other domestic animals. A surgical condition which is peculiar to oxen, but which in them is quite common, is internal hernia, in which the gut is nipped by the spermatic cord, or its peritoneal attachment. Foreign bodies in the stomach and intestines demand no special notice, as they give rise to the same symptoms as in man, according to their character, and either remain inactive till spontaneously expelled, or else require removal by operation. 27 * 420 THE HUMAN SPECIES Nor is there any difference between man and other animals as regards tumours of the rectum and anus. Here, as elsewhere, fibromata, adenomata, sarcomata and carcinomata may occur, and require removal by the surgeon when they threaten health or life. Surgery of the Respiratory Organs. — Rhinology is not so advanced as regards animals as it is in man. It is limited to the recognition, and removal, of foreign bodies and tumours (polypi, fibromata, etc.) in the nose. The so-called rhinoscleroma, which consists of a permanent thickening of the nasal mucous membrane, and the nose itself, following on catarrh, has as yet only been observed in man, and never in animals. On the other hand, animals suffer from diseases of the frontal sinuses and antrum of Highmore, such as actinomycosis, tumours and accumulations of fluid or pus. They require similar operations to those performed on man. Horses, owing to their activity in the service of man, are specially liable to these and other diseases of the nose, such as necrosis of the nasal bones and violent haemorrhages. Conditions calling for surgical interference, such as foreign bodies, new growths or diphtheritic inflammation of the larynx and trachea in animals, differ in no way from the corresponding eventualities in man. Goitres are not so common as in man, but are occasionally seen, especially in carnivora, less often in horses and cattle; they produce the same symptoms, owing to pressure on the trachea, as in man. The extirpation of the goitre is but seldom undertaken, but when complete gives rise to the same cachexia strumipriva, which Kocher first noted in the patients he had operated upon for goitre. Accumulations of air or blood in the pleural cavity are due to the same causes in animals as in man ; the latter are caused by penetrating wounds of the chest, or by perforation of a bronchus. In these cases and also in penetrating wounds of the thorax, bad treatment may lead to a collection of pus (pyothorax), which, like the effusions of blood (haemothorax), must be removed by puncture or a cutting operation (horses, dogs, cattle and other animals). SURGICAL DISEASES 421 Surgery of the Genito- Urinary Organs. — When the kidney is damaged by trauma veterinary surgeons consider it more economical to order the wounded animal to be slaughtered, whereas in man the surgeon would cut down upon and treat the wounded kidney. Quite recently, Lorge, Rubay and other veter- inary surgeons have attempted for the first time to open the kidney from behind for stone, and to close it again after removing the concretion. On the other hand, puncture of the bladder for absolute retention of urine has long been practised. In dogs and swine it is performed suprapubically ; in larger animals through the rectum or perineum. In carnivorous animals and swine stones occur composed of urates, oxalate and cystin ; in herbivora they are mainly calcium phosphate and triple phos- phate ; in sheep they consist of a compound of calcium and magnesium phosphate and silicate. Operations are seldom performed for stone in the bladder in domestic animals, even in the case of dogs which suffer frequently from this condition ; urethrotomy, however, is done if a stone becomes impacted in the urethra. Stricture of the urethra is most commonly seen in horses, hypospadias and epispadias in sheep and dogs, and but rarely in other animals. Veterinary surgeons have frequently to treat prolapse and retroversion of the bladder after difficult labour, a phenomenon which occurs in bitches, mares and sows, but never in women. On the other hand, women suffer from prolapse of the uterus and vagina quite as frequently as cows, mares and sows. Phimosis and paraphimosis are not peculiar to man, but are frequent in certain domestic animals ; phimosis is commonest in dogs, and paraphimosis, a still more frequent occurrence, owing to the shape of the penis ; it is less frequent in bulls and swine. As to hypertrophy of the prostate, which torments so many elderly men, we may console ourselves with the thought that certain animals, such as the dog, and less frequently the horse, are similarly afflicted in their old age. Sarcocele, hydrocele, hasmatocele and varicocele also come under the notice of veterinary surgeons in stallions, bulls and rams. Inflammation of the testis is much more frequent than in- flammation of the epididymis in stallions and bulls. Both pro- 422 THE HUMAN SPECIES cesses when not metastatic do not usually go on to suppuration in animals, but to resolution and restoration of function. The larger number of the swellings of the testis, whether tuberculous, myomatous, cystic, sarcomatous or carcinomatous, demand removal by castration, an operation which is daily per- formed on male domestic animals on purely economic grounds. The changes in physical and psychical condition which occur as a result of removal of the male and female genital glands have attracted the attention of investigators from the earliest times, and have recently formed the subject of an inter- esting treatise by Moebius,1 who holds that these changes are, generally speaking, identical for man and animals. Anatomi- cally, the changes in the sexual organs may first be mentioned. As in man the penis remains small, and the prostate and vesi- culae seminales atrophy, while the mammary glands increase in size, so also in oxen the prostate and vesiculae disappear at the same time as the teats grow large. The reverse condition was observed by Dr. Roberts in India, where females who had been splayed while young became muscular and masculine in type without any development of the external genitals. Castrated animals usually become fat, just as large fatty cushions usually develop in castrated men and women. The changes in the skin connected with the development of secondary sexual character- istics are still more remarkable, and concern males more than females. The growth of hair which characterises the adult man is absent in eunuchs, or only developed as down to the extent seen in women. The resemblance to the female type is seen in the fact that eunuchs seldom develop an " Adam's apple," a fact recorded by Aristotle. In castrated cocks the similarity to the hen bird is seen in the absence of wattles and comb, and the scanty growth of tail feathers which remain flattened as they do in hens. Capons are either unable to crow, or can only do so imperfectly. The poor development of the larynx in human eunuchs is the reason why the voice does not change, but remains high pitched. The larynx is intermediate between the male and female in type. Equally striking are the changes in the bones. According to Moebius, eunuchs are generally tall and slim ; it is not known 1 Moebius, Uber die Wirkung der Kastration. Halle, 1905. SURGICAL DISEASES 423 whether the pelvis is of the female type, but in animals the phenomena are well known. In the males the bones of the fore part are slighter than those of the hinder, and in bitches which have been splayed the larger species have heavier pelves on the whole, but all the relative measurements down to the conjugate diameter of the outlet are smaller. The skull under- goes striking changes. In eunuchs the circumference of the head is small, and the occipital curve, as Gall showed, is con- siderably narrower. Corresponding to this, according to L. Hofmann, is the slightly built skull of male animals after gelding. A capon's skull remains small ; the skulls of bulls and horses do not develop. Some observations on stags are interesting ; if they are gelded early, before the antlers have begun to bud, these do not appear ; if later, the antlers remain small, and after atrophy of the testis on either side a unilateral atrophy of the antler also occurs. Gall has described a remarkable narrowing of the occipital arch in eunuchs. This he considers corresponds to an atrophy of the cerebellum, a view which he has established for animals but not in the case of man. Not only did Vimont find, when carrying out some experiments to test Gall's assertion, that the removal of one testis caused a diminution in the size of the opposite cerebellar hemisphere, but that after double castration the entire brain failed to 'develop, and more especially the cere- bellum. It is clear that the special influence of castration on the cerebellum must both in man and animals lead to corre- sponding mental changes. As a matter of fact, it is well known that the sexual instinct is absent in castrated men and women and animals, and that they have, moreover, lost all courage and love of fighting. From the way in which the observations on human castration agree with those on animals, Moebius comes to the conclusion I had already reached in my treatise on The Double Personal- ity of the MetazoonS) namely, that " to a certain extent each sex contains the developmental potentialities of the other". The genital glands, says Moebius, are not the cause of the secondary sexual characteristics, but only promote them, while hindering the appearance of the secondary characteristics of the other sex. Surgery of the Organs of Locomotion. — Laceration of the 424 THE HUMAN SPECIES muscles in animals, such as horses, have nothing to distinguish them from those in man. Wry-neck (torticollis) can be produced, as in man, by paralysis, inflammation, dislocation or fracture of the cervical vertebrae, or contractures of the neck muscles. Lacerations of fasciae and tendons are common in horses as the result of strain ; the least frequent is laceration of the Tendo Achillis, which has only been observed in cows. A pathological peculiarity in horses, corresponding to Dupuytren's contraction in man, is the condition which depends on a congenital or acquired contracture of the flexor tendons of the fore-foot. " Galls " on the joints and tendon sheaths are extremely common in horses, and are analogous to cysts and ganglia in man. On the fore- limb they may occur either on the flexor or extensor tendons ; tumours on the metacarpus are very laming, still more so are those on the fetlock of the hind-leg. Dislocations are exactly similar to those in man. Dislocations of the lower jaw occur frequently in carnivora, although they are also met with in horses and swine. Dislocations and separation of vertebrae of the sacroiliac joint and of the symphysis pubis occur in horses, and still more often in cattle. Dislocations of the shoulder-joint are much less frequent. in domestic animals than in man, in whom they are the commonest form of disloca- tion. Owing to its firm fixation by means of ligaments, the so-called fore-arm, the fore-foot and phalanges are still less frequently dislocated ; deformities of the phalanges are, however, not uncommon in horses. Of dislocations of the hinder extremity (corresponding to the lower in man), the hip-joint is only commonly dislocated in cattle and other animals ; in horses it is less frequent. Dislocations of the knee-joint, knee-cap (horses, cattle and dogs) and of the fetlock are very rare. In a thesis on the surgical diseases of man attributable to his upright position, P. Albrecht includes spinal curvatures as seldom, or never, met with in animals. It is true that a spine which is supported by four limbs is less easily bent than that of man. Lordosis, or dropped back, however, is frequent, and can be seen any day in the larger domestic animals ; scoliosis and kyphosis, moreover, are by no means unknown in horses and cattle. SURGICAL DISEASES 425 There are, however, joint deformities which are absolutely confined to man ; these are knock-knee (Genu valgum), bandy legs (Genu varum), and the clubfoot (Pes varus, valgus, equinus, calcaneus and plantaris), (Figs. 208-211). No animal suffers from these deformities, which depend on the special structure of the human skeleton. On the other hand, fractures occur both in man and in animals as a result, direct or indirect, of the same daily occur- rences. It would take too long either to enumerate them or to mention the animals in which they most commonly occur. Suffice it to say that all known fractures occur from those of FIG. 208. Pes varus. FIG. 209. Pes valgus. FIG. 210. Pes equinus. FIG. 211. Calcaneus. the skull to those of the bones of the extremities, and are fol- lowed by the same results as to deformity and shortening, ac- cording to the way in which they are treated. The bones of the tail may, however, be fractured, and this is the only point, so far as fractures are concerned, in which man differs from other animals, although it must be remembered that the coccyx may be fractured in man. Caries and necrosis of the bones is not even mentioned in the large work of Moller and Frick, and appears to be seldom, if ever, noticed in domestic animals. These two diseases, how- ever, much' more frequently attack animals in zoological 426 THE HUMAN SPECIES gardens, especially apes and the smaller beasts of prey. It is extremely interesting to find that caries and necrosis may be recognised in the bones of cave bears. Walther found a lumbar vertebra partly destroyed by caries, and two lower jawbones in which exostoses had occurred due to caries arising in the alveoli. He was able to recognise a sequestrum lying within the casing of dead bone in a necrotic humerus from a cave bear. 3. Diseases of the Higher Sense Organs. The pathology and pathological anatomy of the higher sense organs which has attained the rank of a speciality in the case of human medicine, will now be considered as a kind of adjunct to the foregoing sections on special comparative surgery. Although from the anatomical point of view the higher animals may be said to suffer from the same diseases of the nose and ear as man, they have not, for obvious reasons, been made the objects of similar special studies. With regard to diseases of the nose, the short notice given above must suffice, and the chapters on diseases of the ears are equally short and condensed in most veterinary text-books. As in man, two forms of inflammation of the external audi- tory meatus, the acute and the chronic, are known (Otitis ex- terna) ; they occur most frequently in dogs, less frequently in horses and other animals. The etiology and symptoms are the same as in man ; and the papillomata, which form a sequel to the chronic form, require the same treatment when diagnosed. Chronic catarrh of the external ear can be diagnosed in horses, but, according to Moller and Frick, inflammation of the middle ear (Otitis media) and labyrinth (Otitis interna) generally re- main untreated and are not recognised till after death. They are the result of Otitis externa, the introduction of foreign bodies, the growth of parasitic organisms or of tuberculosis. Veterinary ophthalmology alone has become during the last ten years a well-established speciality, owing to the ease with which the eyes of animals can be examined with the ophthalmoscope ; far-reaching comparisons with pathological conditions in man have thus been established. Dr. H. Moller has published a clear and well-written text-book on veterinary oph- thalmic surgery on which much of what follows here is founded. DISEASES OF THE HIGHER SENSE ORGANS 427 Lesions of the cornea are very frequent in all domestic animals, as are their sequelae, anterior synechiae, prolapse of the iris, opacities and scars (at any rate in dogs) ; in dogs and horses superficial and deep inflammations and ulcers are also common. Fistula and staphyloma follow as in man, as the result of perforation. New growths, pterygium and dermoids are not infrequent in horses, dogs and sheep. The various forms of inflammation of the conjunctiva from simple catarrh to purulent (blenorrhagic) or diphtheritic con- junctivitis, appear with the same symptoms as in man. Blenor- rhagic inflammation is often most extensive in cattle, sheep and dogs ; the diphtheritic form is confined to fowls, pigeons and other birds, in which primary diphtheria of the throat and nose has occurred. Diseases of the membrana nictitans are peculiar to animals ; wounds occur in horses, cattle and dogs ; chronic inflammation, accompanied by thickening, in dogs and swine; fibromata in the larger animals, and prolapse in dogs and swine. Coloboma also occurs in animals, as a result of disturbances in the normal formation of the fcetal pupil ; the pupil may be closed either by posterior synechiae, or by swelling of the uvea. Inflammation of the iris is very frequent, either primary or secondary, to disease of the ciliary body or choroid. The causes of acute inflammation of the iris are either trau- matism or infection. Iritis often extends to the ciliary body and choroid, and if primarily infective it may lead to a general purulent inflammation of the eye (panophthalmitis). Night blindness in horses is rather different from that in man ; in man it is due to a decrease in central vision, conditioned by a rapid contraction of the visual field when the light is deficient, without any internal inflammation of the eye. In the horse it is due to a periodically recurrent irido-choroiditis of an infectious character, leading to destruction of the retina and blindness in one or both eyes. As in children so in young domestic animals (dogs and horses) opacity of the lens may occur as a congenital defect. Cataract generally, however, occurs later both in these and in other animals (bears, hyaenas, wolves, the smaller felidae, and other small beasts of prey) ; it is the result of metabolic dis- 428 THE HUMAN SPECIES turbances, former inflammation, haemorrhages into the anterior chamber, or diabetes. The various operations for cataract are also performed on animals. Glaucoma, which von Graefe showed was due to an abnormal increase in intraocular tension, occurs, according to Moller, in dogs and rabbits, though it is not common. It is characterised, as in man, by the greenish hue of the retinal reflex and the hardness of the eyeball ; the ophthalmoscope shows the same hollowing of the optic disc. The condition known as amaurosis in animals is the result of various diseases of the retina, optic nerve or visual centre in the brain. Primary inflammation of the retina is seldom seen in animals. In most cases it is secondary to choroiditis. Inflam- mation at the point wrhere the optic nerve enters the retina can easily be recognised by the ophthalmoscope, as can separation of the retina (dogs and horses), and haemorrhages, which are frequent as the result of the infections, and of heart failure. Infectious diseases in horses and cattle also give rise to in- flammation of the optic nerve before its entry into the medulla (retrobulbar neuritis). Diseased conditions of the vitreous body are especially common in horses, and are caused by disease of the choroid or retina. The latter are usually due to wounds of the sclerotic, and less often to inflammation. Dogs, lambs and cows are predisposed to hydrophthalmos, in which the outer covering of the eye extends through a complete sclerochoroidal staphyloma. The following conditions are similar to those seen in man, and require similar treatment : inflammation of the lacrymal sac (horses and cattle) ; closure or narrowing of the lacrymal duct (horses, donkeys and mules) ; fistula (horses, cattle and dogs) ; wounds and inflammation of the eyelids ; ectropia and entropia (dogs). Swelling of the lids, ptosis and malignant or benign tumours in animals have no special characteristics. The same lesions and inflammations of the soft parts of the orbit may occur in horses and cattle as the result of work, and in dogs as the result of fighting, and may occasionally result in exophthalmos. PATHOLOGY OF PREGNANCY AND PARTURITION 429 With regard to lesions in the external nerves of the eye, nystagmus has a more serious significance. In man it may be the result of myopia, either congenital or acquired in early life ; in this case it leads to no consequences but has very little chance of improvement. In animals, such as swine, horses and dogs, it is always the result of poisoning or of cerebral disease, and thus demands a cautious prognosis. Squint, on the other hand, has hardly any significance in animals ; internal strabismus, due to paralysis of the external recti muscles, is commonest in horses, cows and dogs. As might be expected, nothing is known of defects of ac- commodation in animals. With regard to refraction, Matthies- sen, Berlin and others have shown that a slight grade of hyper- metropia is present in most domestic animals ; Berlin estimates it in horses as from one to two diopters, though higher degrees may of course occur. A frequent cause of squint in horses is astigmatism, that is to say, an inequality of the dioptric apparatus in its different diameters; according to Moller, it is usually present in horses and other domestic animals. 4. Pathology of Pregnancy and Parturition. (a) Diseases of Pregnancy. Pregnancy in the human being may be unfavourably in- fluenced by abnormal conditions of the uterus which in other mammals are either non-existent or else approximate to the normal. Thus, a uterus unicornis in the human species may have its single horn so much stretched by the growth of the foetus that the wall is thinned and eventually ruptured. The same thing may take place in the uterus bicornis when a foetus develops in one-half. In most carnivora and edentata, and in some rodents, the uterus is divided into two parts by an incomplete septum, and the young lie to the right and left. A human uterus bilocularis, with a septum arising from the fundus, causes a cross position of the foetus like the uterus bicornis, which is the normal form of uterus in ruminants, pachyderms and ungulates, and in them gives rise to no difficulties during pregnancy. Acute retroversion due to external forces, or one which is 430 THE HUMAN SPECIES slowly developed, is connected with the upright position and does not occur in animals ; nor do anteversion, due to a pendulous abdomen, or the oblique position of the pregnant uterus. As against these purely human abnormalities we may set others which are peculiar to animals. Twisting of the uterus round its long axis due to the pull on the broad ligaments exerted by the growth of the foetus in utero, occurs in cows, and less fre- quently in sheep and goats, while it is still less common in horses, swine and dogs. In other cases a hernia of the uterus may occur after rupture of the abdominal muscles, so that the pregnant uterus lies in a sack formed solely of the integument. In bitches hernia of the uterus into the inguinal canal may occur. Prolapse and procidentia of the pregnant uterus may occur in both human beings and animals ; the latter condition is frequently associated with prolapse of the vagina. In the human female prolapse and procidentia commonly occur only during the first three months, but in these they are apparently fairly common. Prolapse of the vagina only occurs in multi- parse. From the fourth month onward this untoward event, which is frequently the cause of abortion, becomes less and less common. Among domestic animals, cows, mares and goats are especially liable to prolapse of the vagina. Lesions of the foetus due to external mechanical influences during pregnancy occur, though not frequently, both in human beings and animals. Haemorrhages caused by the presence of innocent or malig- nant growths are also common to both during this period. Such haemorrhages are also due in domestic animals, as mares and cows, to apoplexy of the chorionic villi, or to a kind of placenta prasvia, when the network of villi belonging to the so- called Chorion l&ve is implanted in the region of the internal os as an accessory placenta. A single, complete, central or lateral placenta praevia is peculiar to the human species, and is connected with the erect position. With regard to dropsy of the fcetal membranes, caused by general fcetal oedema in cases of circulatory and renal disease, a difference is to be noted between human beings and animals. In human beings in whom the allantois disappears early, dropsy can only occur in the amnion, while the early obliteration PATHOLOGY OF PREGNANCY AND PARTURITION 431 of the urachus causes the urine also to drain into the amniotic cavity. Thus hydramnios is the only condition found in human beings. In the domestic animals, however, dropsy both of the amnion and of the persistent allantois may take place, and the urine drain into the latter sac owing to the urachus remaining open till birth. Development of the fertilised ovum outside the uterus, either in the ovaries, Fallopian tubes, or in the peritoneal cavity, occurs in animals as in man, though with important differences. In the human subject extra uterine gestation, though rare, is always a true primary condition ; in animals, such as rabbits, hares, swine, dogs, sheep, cattle and horses, besides this there is a false extra-uterine gestation constituting the majority of the cases, due to rupture of the uterus and implantation of the foetus in the peritoneal cavity, where it may, or may not, undergo further development. CEdema of the legs and external genitals constitutes one of the most frequent symptoms of pregnancy in the human female. This oedema is often associated with varicose veins, which per- sist in a slighter degree after parturition. A similar oedema of the hind-legs and udder is common in pregnant mares and cows, but varicose veins are not mentioned in works on veter- inary obstetrics, either because they do not occur, or because their presence is concealed by the animal's hair. Nervous complications of pregnancy peculiar to women are fainting, hysterical convulsions, and eclampsia due to renal disease. It cannot be decided whether pregnant animals, like women, suffer from neuralgic pains of various kinds, as there are no means of recognising such a condition. It is certain, however, that mares and cows often experience false or prema- ture pains while the os uteri is closed and the udders still flaccid ; cows and goats suffer from cramp of the cervix uteri without dilatation of the os, and also from premature pains and distension of the udder as a result of old cicatrices and thicken- ing of the walls of the cervix. As might be expected these premature pains often result in abortion. In human beings the term abortion is used to mean expul- sion of the foetus during the first three months ; this condition is due either to extreme excitability on the part of the mother, 432 THE HUMAN SPECIES abnormalities of the uterus, such as new growths or displace- ments, to the occurrence of a menstrual period, or finally to any cause producing death of the foetus. Habitual abortion is very frequent in women affected with syphilis. In Bartel's work, recently edited by Ploss, the commonest cause of abortion in savage races all over the world is said to be overstraining of the women by hard work, tiring journeys or carrying heavy loads. To this, to the difficulty of rearing children, and often to the sterility of the soil must be added the frequency of artificial abortion in all savage races in America, Asia, Africa and Aus- tralia. European observers admit that the same motives for this may exist as are found in civilised peoples, namely, indo- lence on the part of women, and attempts of erring girls, and wives, to get rid as soon as possible of the evidence of their guilt, in which they may be helped by more experienced women. Artificial abortion, as practised by savage and civilised peoples, or induced in cases of necessity by medical men, is a special attainment of man which no animal has ever succeeded in reaching. Natural abortion is much more frequent in animals. Though unusual in the smaller ruminants, and still more unusual in the carnivora and swine, it occurs often enough among the larger domestic animals, such as mares and cows ; in the former it is usually between the fourth and ninth month, and in the latter between the third and seventh. Sporadic cases occur as the result of circumstances causing death of the foetus, such as disease of the placenta, overstrain, and psychical influences (anxiety or terror), or, as the result of eating bad fodder or ergot (in rye, various grasses or reeds), a whole series of animals will abort one after the other ; infective material may indeed produce abortion throughout a whole herd or stable. Artificial abortion, which is not infrequently practised by veterinary surgeons, has but little in common with the patho- logical variety. It is a measure which is adopted as in human beings when it is rendered necessary by a contracted pelvis or by maternal disease ; the principal conditions for inducing pre- mature labour are the extreme asthenia of old mothers, oedema of the fcetal membranes, serious haemorrhage, or an extreme degree of prolapse of the vagina. PATHOLOGY OF PREGNANCY AND PARTURITION 433 In human beings the term miscarriage is used when the foetus is not viable and is expelled before the twenty-eighth week ; the term premature birth is used when the foetus is between the twenty-eighth and thirty-eighth week and is cap- able of survival. The viability of the foetus in domestic animals must be the ground for diagnosing premature birth. (b) Pathological Complications of Parturition. Among savage people the causes preventing birth are reckoned to be weak pains, bad position or want of activity of the foetus, and disproportion between the size of the child and the mother's genital canal, and magic. This latter, and also the want of activity on the part of the foetus, are childishly simple ideas, but with these exceptions the views of savage nations are very close to the reality, especially in the entire absence of external aid. The circumstances hindering birth in civilised people are known to be abnormal size of the foetus, or of one of its parts ; abnormalities in the membranes, umbilical cord or placenta ; anomalies in the uterus or external genitals ; faulty position of the foetus ; contracted pelvis, and, after delivery, retained placenta. Abnormal size of the foetus may hinder parturition both in human beings and in our domestic animals. The abnormality may affect the whole body or only one part. The belly may be excessively large owing to ascites, or the head may be enlarged by hydrocephalus, which in both cases is often a hindrance to birth. But apart from any collection of fluid in the brain, the child's head may have a disproportionately large circumference. In man this may occur in the children of fathers whose heads are very large, and in calves and puppies under similar circum- stances. Deformities and tumours, both in human and animal foetuses, and curvatures and contractures in the latter, may form a more or less complete obstacle to delivery. In the vast majority of cases, only one foetus is developed in the human uterus. The simultaneous presence of more than one foetus in the uterus, besides causing increased trouble during pregnancy, interferes with parturition, as abnormal positions of 28 434 THE HUMAN SPECIES the foetus, prolapse of the cord and of the extremities, are more common under these circumstances. Twins, either from one ovum and thus always of the same sex, or from two ova and then generally of different sexes, are fairly common, occurring on an average once in eighty-seven births. Triplets are rare, one in 7,600 births, and quadruplets and quinqueplets are still rarer. Multiple pregnancy is the rule in many mammals, and then it occasions no disturbance at birth. In uniparous mammals, however, the development of twins or triplets is a disturbing factor in parturition just as it is in the case of human beings. Twins occur in sheep fifty-six times in 300 births, in cows once in seventy-five, in mares once in 387. In goats twins are usual. The condition of the fcetal membranes is of much greater importance to the course of parturition in both human beings and animals. If the membranes are too thin, they rupture too soon for the proper dilatation of the os uteri, and the early escape of the amniotic fluid thus prolongs labour. A like result ensues when the membranes are too thick to rupture spontaneously at the proper time, so that the entry of the fcetal head into the true pelvis is delayed. The amount of amniotic fluid is also of considerable importance ; if it is too great, or too small, unto- ward disturbances of parturition are liable to occur both in man and animals. If the amount is too small, the protruding bag of membranes which is required to dilate the os uteri is only incompletely formed, and after the escape of the little fluid which exists the labour is "dry". If the amount of fluid is too great the foetus is allowed too much mobility, and various ab- normal positions result ; when the membranes rupture, the limbs or the umbilical cord may prolapse. We have already referred to placenta prsevia (central or lateral) which is, properly speaking, peculiar to the human race. Abnormalities in the human placental tissues (deposits of fibrin, cysts, inflammatory changes, etc.) appear to be very rare in animals and are only very briefly dealt with in veterinary text- books. It is impossible at present to say whether complete separation of the placenta, which is very rare in human beings, has ever been known to occur in animals. Abnormal insertion of the umbilical cord into various parts of the placenta, torsion and knots in the cord, such as occur in PATHOLOGY OF PREGNANCY AND PARTURITION 435 the human subject, have no greater effect on the course of parturition when they are observed in animals. The length of the cord is, however, in both cases of more importance. If it is too short the entry of the head into the true pelvis will be de- layed, and often there will be a separation of the placenta and consequent haemorrhage. If it is too long it may, during the period of gestation, become twisted round the neck or other portion of the body of the foetus, and so delay parturition, or in human beings it may become prolapsed ; if the cord cannot be replaced, prolapse constitutes a serious complication, and may lead to the death of the child during parturition. Lacerations of the cord during labour are much more dangerous to the human child than to young animals, unless they are at once ligatured. This difference depends on the behaviour of the umbilical vessels, which in the case of animals become sealed immediately after a laceration, whereas in the case of human beings, unless a ligature is applied, a dangerous haemorrhage occurs. It is obvious that both in human beings and animals unusual rigidity of the external os uteri, and superficial or still more deep-seated strictures, will cause serious obstructions to the course of parturition. In women, mares, cows and bitches a narrowing of the vagina or vulva, due to antecedent wounds or inflammation, may cause rupture of the uterus of the neighbour- ing large blood vessels or the vagina, unless operative assistance is promptly rendered. In women it may happen in the second or third stage of labour that, if traction is made on the cord while the placenta is still firmly attached, the placental site becomes inverted and dragged through the os, until in the most extreme cases the entire uterus is turned inside out and pulled out through the vulva. In domestic animals similar causes lead to inversion and finally to prolapse of the inverted uterus. In ruminants, with their multiple placentas, the tendency to prolapse is much greater than in animals with single or widely spread placentae ; "especially as in the first -named animals the fusion of the foetal and maternal portions of the placenta is much more in- timate and the method of its detachment is quite different from that which obtains in the others " (Franck). 28 * 436 THE HUMAN SPECIES The character of the pains during labour is of supreme im- portance both in human beings and animals. All diminution in their strength, or in the extent to which they affect the uterine tissue, is more or less a hindrance to the course of par- turition. Excessive or tetanic contractions are especially dis- astrous when parturition cannot proceed owing to a faulty position or attitude of the foetus, and the accoucheur is prevented from seizing it owing to the extreme pressure. If the condition is not relieved lacerations and other important complications may ensue. M. Schmidt reports two cases of laceration of the uterus in lionesses in the Zoological Gardens at Grenoble and Frankfort-on-the-Main. Abnormal contractions of certain sec- tions of the uterus also tend seriously to prolong parturition both in human beings and animals, though not to such a dangerous extent. These contractions occur where the musculature is circularly arranged as at the internal and external os. The delay caused by weak pains can be still more easily understood, whether involving the whole uterus or only a portion thereof. Both in human beings and animals parturition cannot proceed when the musculature is tired out by long and fruitless pains, especially when the position of the foetus is faulty. Although in the various factors causing prolonged parturi- tion which have hitherto been described there is a general re- semblance between human beings and animals, a marked differ- ence will be noted when we consider the various malpositions of the foetus in utero : although these malpositions may in both cases be classified as head presentations, breech presentations and transverse presentations. The main difference between human beings and animals is concerned with cephalic presenta- tions, and is due to the different shape of the skull. In human beings the calvarium is especially developed, and this presents most frequently ; when the pelvis is normal this presentation has the best prognosis, though it is not quite so good when the head is placed obliquely, when the occiput is rotated backwards, or where the deeper parts are transverse. Face presentations, on the other hand, are among the most unfavourable, as labour is prolonged and the child's life threatened. In animals, on the other hand, face presentations are normal, and presentation of the calvarium one of the worst complications of labour. In human PATHOLOGY OF PREGNANCY AND PARTURITION 437 beings, owing to the shortness of the neck, malposition of the head is almost inconceivable, but among the larger domestic animals, such as foals, malpositions of the head are, owing to the length of the neck, very common. A lateral position is especially common, and after that positions in which the head is bent downwards or backwards. Conditions depending on malposition of the fore-legs are still more complicated ; here one or both ankles, or one or both shoulders may present. Breech presentations both in women and female domestic animals are abnormalities which tend to make labour more difficult. In the former, those in which one or more limbs lie beside the breech may be distinguished, and also those in which the foot or knee comes down before the breech ; these may all be again divided into two positions, according as the child's back is turned towards the right or left side of the mother. If the child's back is turned towards the back of the mother, the position must be regarded as abnormal. Breech and footling presentations have been recognised among savage peoples from time .immemorial, before any more accurate diagnosis of the presentation could be made. Among domestic animals besides pure breech presentations there are malpositions of the hind limbs and malpositions of the tail. The position of the young may thus be " lower " (or towards the mother's belly), right or left (towards the mother's corresponding flank), as normally among domestic animals the back is turned towards the back of the mother. Malpositions of the limbs are more serious in animals; in human beings they are short and the joints are but little developed, but in domestic animals the long limbs and powerful joints offer much more resistance to the correcting hand of the accoucheur. It is, indeed, utterly impossible to convert a breech presentation into a head presentation in the case of domestic animals. If the human foetus does not present either by the head or the breech, its position must be either transverse or oblique. In the first case the long diameter of the child's trunk is parallel with the transverse diameter of the uterus, and the head may be found in the mother's right or left side; the back, the belly or the right or left flank of the child may be downwards, and, 438 THE HUMAN SPECIES according to the position of the foetus, one or more extremity may lie on the os uteri, or one of the upper extremities may prolapse. It is characteristic of human transverse presentations that they do not arise during labour, but are due to various antecedent causes, and that in small and badly developed or macerated foetuses, the malposition corrects itself, while in all other cases version is possible. The conditions in the case of domestic animals are very different. The transverse position arises during, and as the result of, labour, and is developed from some other position. It is commoner in horses than cattle. The young lie transversely, with the back strongly bent and with one end of the body lower than the other, so that either the back or the belly is turned towards the inlet of the pelvis. Version is possible in small animals, if the size of the genital canal permits ; in larger animals version is only possible when one half of the foetus has been torn away. Oblique positions only differ from transverse positions in degree, and are only met with in the human subject. The long axis of the child's trunk forms an acute angle with the long diameter of the uterus, so that ob- viously either the head or the breech must lie close to the os uteri. This circumstance renders the oblique position more favourable than the transverse. But whereas the oblique position is peculiar to human beings, an abnormal position is observed in animals which can never occur in man owing to the upright posture. This is the vertical position of the foetus, in which one end lies against the mother's belly and the other against her sacrum or lumbar vertebrae, so that it sits or stands in the uterus with either its back or its belly opposite the pelvic inlet. Considerable differences may thus be demonstrated between the various factors tending to obstruct labour in human beings and those found in animals. The most important difference, however, still remains to be described, viz., the influence of the pelvis on the course of parturition. As regards this, the domes- tic animals in which the course of parturition can be observed are much more suitably framed from an anatomical point of view than the human female. Not only is the pelvis in animals wide and roomy, but its component parts are more movable PATHOLOGY OF PREGNANCY AND PARTURITION 439 than those of woman. The course of labour in mares is rendered much easier by the fact that the only important structure closing in the pelvis is the broad pelvic fascia. In cows the mobility of the sacro-iliac joint and the sacro-lumbar joint is greater than in mares. Labour in sheep and goats is still easier owing to the mobility of the upper sacral vertebrae, which renders possible a considerable widening of the pelvic outlet. In swine difficult labour is very rare, owing to the marked concavity of the sacrum and the extreme mobility of the sacro-lumbar and the sacro-iliac joints. In bitches the false pelvis is more capacious than in any other domestic animal, and the sacro-iliac joint is so mov- able as to form a regular diarthrosis. In addition to the FIG. 212. Robert's pelvis. (Spath.) FIG. 213. Naegele's pelvis. (Spath.) anatomical advantage enjoyed by domestic animals, there is the fact that pathological changes in the pelvis, causing a diminu- tion of the pelvic diameters, are much less common. Franck indeed states that a narrow pelvis in adult animals only exists in a relative sense when the young one or the foetal head, that is to say, is disproportionately large. The only pelvic deformities with which he is acquainted are those due to fracture of the pelvic bones, exostosis and ankylosis of the joints, such as the sacro-iliac, whereby a pelvis similar to Robert's pelvis may be formed in animals. As we have seen, primitive peoples do not reckon a con- tracted pelvis among the hindrances to parturition. According to the universal testimony of experienced and expert travellers, 440 THE HUMAN SPECIES the course of labour is, in the vast majority of cases, a much easier one, as rachitic, or otherwise contracted pelves are all but unknown. Especially favourable conditions obtain among most races of Australasia and Oceania, and the savage peoples of Asia, Africa and America. H. Fritsch makes the following" weighty pronouncement on this matter : " It is obvious that un- communicative savages can always evade troublesome questions by saying that no assistance is ever needful during parturition. Some experience is necessary in order to test the truth of this statement, as any inspection or examination during the act would be entirely impossible. To understand, however, why severe labours are so infrequent among such races, one must remember that very contracted, or absolutely too contracted pelves hardly ever exist. On the one hand, bone diseases (rhachitis) leading to pelvic deformity are unknown, and on the other hand, badly built indi- viduals perish through insufficient nourishment. In the FIG. 214. Osteomalacic pelvis. (Spath.) cage Qf a crjpplec{ individual, it must not be forgotten that generally a woman is a chattel, and a bad chattel is unlikely to find a bidder at most auctions, especially as women are mainly married in order to .be used as labourers. There is also considerable evidence (e.g., Wernich's measurements and weights) showing that the children are remarkably small, have but slightly developed occiputs, very round heads and very soft bones. From all this it may be gathered that difficult labour is a rarity." If we compare what is taught in our own midwifery text- books as to the influence of the pelvis in prolonging labour with this favourable account, we find a whole list of pelvic deformities, partly congenital and partly acquired later in life. There is the generally contracted pelvis of dwarfs, and the common shorten- ing of the conjugate diameter caused by a too protruding sacral PATHOLOGY OF PREGNANCY AND PARTURITION 441 promontory ; the funnel-shaped pelvis and the pelvis of male type, which is deeper and narrower transversely than the usual female pelvis. To these must be added pelvic deformities secondary to some pathological condition. By defective development of the two wings of the sacrum, and ankylosis of both sacro-iliac joints, the pelvis of Robert is produced (Fig. 212) ; Naegele's pelvis is formed by ankylosis of one sacro-iliac joint and imperfect development of the wing of the sacrum on that side, producing a narrow slanting cavity. Asymmetry of the pelvis, with con- traction of one-half, may result from unequal development of the transverse processes of the lower lumbar or first sacral vertebrae ; or the pelvis may be narrowed by the excessive growth of cer- tain bony projections (ridges or processes) . Two bone diseases, both of them special forms of inflammation, are speci- ally unfavourable to the proper development of the pelvis. Rhachitis produces either a dimi- nution of the conjugate diameter with a normal or increased transverse measurement, or a gene- FIG. 215. Pelvis in hip-joint disease. (Spath.) ral decrease in all diameters. Osteomalacia, on the other hand, in which the bones are abnormally soft, causes a change of shape which is due to the pressure of the body-weight from above and on both sides. The promontory of the sacrum arid the ilia are forced inwards and the symphysis forwards into a peaked shape. Pelves with ankylosis of the sacro-iliac joints are very rare ; deformities due to single or double hip-joint disease (Fig. 215) are more common, whilst commonest of all are those in which the contraction is due to curvature of the spine such as kyphosis or scoliosis (Fig. 216). It is these contracted pelves which easily give rise to more or less deep and extensive tearing of the perineum. Laceration of the perineum appears to be confined to human 442 THE HUMAN SPECIES beings, at least no mention is made of it in veterinary text-books on obstetrics. There is, however, a still more severe and destructive lesion, which may occur both in human beings and animals, though it is fortunately rare in both, namely, expul- sion of the head (or in animals of the head and fore-limbs) through the tissues of the vagina or perineum owing to abnormal rigidity of the external genital opening. Franck records a series of cases occurring in mares in which certain parts of the foals, the head, feet, or both together, were expelled through a laceration in the upper wall of the vagina and the lower wall of the rectum, a condition certainly fatal to the mother unless re-position could be promptly effected. Finally, when the foetus is born the completion of the labour may be delayed both in human beings and animals if the after- birth does not come away pro- perly, and dangerous haemorrhage occurs. Retention of the placenta is not uncommon in women, and in some may occur more than once. Among animals it occurs most frequently in cows, less frequently in other ruminants, seldom in horses, and less fre- quently of all in the multifarious domestic animals. Removal of the placenta by external manipulation is only possible in human beings. In both human beings and animals it may be seized from within the genital canal, and its removal is followed by contraction of the uterus and cessation of the haemorrhages. FIG. 216. Contracted pelvis in lordosis. (Spath.) APPENDIX. Comparative Therapeutics. IN the foregoing researches into comparative pathology we have found much that is common to man and animals, and also much that is peculiar and specific for man. The further question now arises whether the attempt to overcome these pathological con- ditions by corresponding therapeutic measures is absolutely peculiar to man, or whether, and if so to what extent, it may also be observed among animals. In both cases we must dis- tinguish between purely private and individual therapeutics, and those measures which are social in character and extend to others of the same species. The ancients do not appear to have entertained any doubt as to the power of animals to help themselves. Evidence of this is seen in the most fabulous tales recounted by Aristotle, Pliny, Aelian, etc. According to Pliny, the hippopotamus when it has overeaten itself and feels too plethoric, bleeds itself by driving the sharp end of a broken pipe into a vein. The Egyptian ibis, and the white stork so common in Germany are said to use their beaks as enema tubes ; bears when their eyes get weak allow the bees to sting them on the head ; swallows use the seeds of the celandine to clear dimness of vision, and does use the fennel-like plant Seseli libanotis to ensure easy parturition ; ringdoves, fowls, blackbirds and partridges cure the indigestion which recurs every year by means of bay leaves ; pigeons and fowls also use the plant Helxine ; ducks and other water birds syderis, and cranes marsh reeds, while bears employ the juice of the arum as a laxative. Numerous examples of how animals cure themselves when poisoned are quoted by the ancients. Thus bears who have swallowed mandrake, eat ants as an antidote ; panthers poisoned by an arrow swallow human excrement, and tortoises when 443 444 APPENDIX bitten by a poisonous snake seek a kind of origanum, \vhile stags poisoned by a spider can cure themselves by eating crayfish. Indeed, as to the treatment of wounds, Pliny states that stags when wounded by arrows only have to eat the leaves of the dictamnus in order to cause the arrow to fall out, and that weasels when wounded in their battles with rats heal their wounds by nibbling rue. However incredible these tales of the classical authors may appear, we cannot altogether deny the possibility that animals may know of remedies for their illnesses and accidents. Everyday experience tells us that the dog's method of curing indigestion by eating grass is by no means a bad one. It is equally rational in stags, boars and other animals to cool their overheated blood in a cold spring. We are justified then in cautiously inquiring whether more highly organised animals when bitten by a poisoned snake may not seek to stay the fui ther action of the poison by using some familiar plant as an antidote. The mongoose, an ichneumon inhabiting Java, is said by trustworthy travellers of the present day to dig up the bitter root of the ophiorrhiza mungo when bitten by a cobra; he rubs the wound with the juice of this root which has such an invigorating effect that he is soon ready to begin the fight again. In support of this account it may be mentioned that the root of this plant has a reputation all over India as an antidote to snake poison, and natives point out the little mongoose as the origin of their knowledge of the action of this plant. If he could really be healed in this manner the mongoose ought by now to have ac- quired an immunity against snake poisons, just as the hedgehog, which is said by Lenz and Brehm to be immune to the bite of the adder, has acquired this property as a heritage from many generations of hedgehogs who have become immune owing to many successive snake-bites from which they have been fortunate enough to recover. The question as to whether wounded animals know how to treat themselves is a less complicated matter. We may see every day how dogs and cats lick freshly made and bleeding wounds, and by this method, vigorously applied, obtain remark- ably rapid healing without suppuration. The reports of travel- lers are unanimous in stating that large animals invariably lick their wounds whenever they can reach them with their tongues. Wounded apes endeavour to staunch the blood by pressing APPENDIX 445 their hand upon the wound ; they also try to pull out arrows with their hands, just as they are accustomed to pull out splinters of wood or thorns very successfully when these are accessible. How appropriate, too, is the method of progression adopted by dogs when they have broken one of their legs! When the first pain and agony is over they soon find out how to get about on three legs, and learn how to hold the broken leg that the fracture heals without any shortening to speak of even though no bandage is applied. The licking of the wound is simply an instinct ; the removal of thorns or splinters of wood by apes implies a certain degree of reflection. A still higher degree may be seen in the elephant, which, as Bouchinet states for a fact, having a large leech in his left axilla, removed it very skilfully with a splinter of bamboo. If this tale is really true it shows that a specially highly gifted animal may make for itself a suitable instrument for purposes of surgical aid. These evidences of the capabilities of the animal mind are of uncommon interest as regards the comprehension of the beginnings of therapeutics ; but it is still more interesting to find that the same motives which have led mankind on to the higher developments of the art, obtain among animals, the motives, namely, of sympathy and fellow-feeling for another's pain. Indeed, the fact is beyond dispute that animals can feel sympathy for each other and a desire to go to each other's assistance. I will not now relate the many oft-told instances in which animals have had compassion on those of their kind which through extreme youth or age were unable to help them- selves. In Ludwig Biichner's book on the love of life in the animal world, many examples have been collected. We are only concerned here with the help rendered to one another by animals in cases of illness or accident. In the London Zoologi- cal Gardens were two baboons who inhabited the same cage, and one of them was bitten in the arm by a dog-faced monkey who lived next him. The wounded ape ran howling into the middle of the cage with his arm held tight against his breast. His comrade went up to him, took him in his arms and con- tinued to soothe him in affectionate tones until he ceased his lamentations. But the mutual helpfulness of animals is not confined to such expressions of sympathy. It is quite touch- ing to see the way in which a dog endeavours to support 446 APPENDIX the broken lirnb of his comrade ; there is also quite a credible story of a white horse who licked a wound made by a set on on the chest of a companion which the latter could not reach owing to his short halter. In contrast to these actual examples of mutual help, stands the fact that parrots in their antipathy against those who are sick, crippled or wounded, either of their own or some other variety of bird, hunt them down and kill them. In this case, according to Biichner, pity is extinguished by the stronger feel- ing of abhorrence, and the condition must be regarded as an exception to what is a very general rule among animals — a rule especially well marked among the gregarians. It is certain, says Darwin, that animals living in communities have a feeling of love for one another which is much less marked in those living solitary lives. The feeling of pity, which is shown in various instinctive actions, is taken by Darwin as the explanation of that heredi- tary impulse which compels social animals to the exercise of mutual helpfulness. Since instances of neighbourly help are especially to be found in social animals, it is not surprising that these beginnings of therapeutics should be especially observed in the insects which dwell in communities. We know that these inhabitants of the insect commonwealths are endowed with a brain, which, for all its minute size, is of so fine a quality that it has been the wonder of all students of nature. The ants stand highest in the series, and among them examples of the treatment of the sick and wounded have been reported which would seem incredible were they not vouched for by competent observers such as Huber, Forel, Lubbock and others. Ants take in other ants when sick or wounded, provided that they belong to the same species, and that the disease or damage is not too severe. In the latter case they are regarded as hopeless, carried outside the ant-hill and abandoned. But even in this there is, according to the reports of the above-named observers, the greatest difference both in willingness and in dexterity between different individuals. Forel observed a colony of white ants (Formica pratensis) while in the act of changing their place of abode. On the sum- mit of the old nest an obviously sick ant was moving with tottering steps, drooping antennae and half-closed jaws. Other ants came up to it, stroked it and looked at it in various places and tried gently to drag it inside the nest. Suddenly one of APPENDIX 447 those going out of the nest came up, pushed the others on one side and tried to seize the sick one. After many fruitless attempts it succeeded at last in doubling up its legs and antennae, and allowed itself to be carried by its neighbour into the new nest. Moggridge saw a still more remarkable in- stance of the pity felt by one ant (an atta) for another. It dragged the sick one to a little spot of water, immersed it for a few moments and then took it out again with the greatest care to dry in the sun. To these well-authenticated instances of the treatment of the sick may be added some equally interesting cases of the care of the wounded. Latreille cut off the antennae of some workers among the yellow ants in order to see what would happen. The mutilated insects ran hither and thither as if mad, without any knowledge of their whereabouts ; then some other workers from the same nest came up to them, laid their tongues on the wounded spots and let a drop of moisture fall on them. Lat- reille observed this with a lens, and clearly saw this process several times repeated. M. de Saint Furgeau remarks that " an ant never meets a wounded comrade of the same species without seizing it and carrying it into the nest ". Lubbock's observa- tions, however, are more detailed. He placed a wounded ant on a piece of paper; a previously marked ant passed the wounded one twelve times without taking any notice of it. Three others also ran hither and thither without attending to it, but a fifth picked it up and carried it into the nest. The foresight of ants even goes so far as to provide for their cripples. An ant born without antennae, which had never been seen to leave the nest, one day went out while Lubbock was watching, and was immediately attacked by some hostile ants. It lay there, badly wounded, and unable to move, when by chance some other ants from the same nest came by, examined the poor damaged creature, carefully picked it up and carried it into the nest. The same observer knew of a crippled worker in a nest of Formica fusca which was unable to feed itself owing to a contraction of the mouth and a deformity of the antennae which were rolled up in a spiral. It was, how- ever, taken by its companions on their expeditions, and, thanks to this provident care, lived for several months. Throughout this work we have tried by means of a critical comparison between man and the other animals to determine 448 APPENDIX what are specifically human characteristics. Now, as we have seen, there is a considerable power of medical self-help in all the more highly organised animals, as well as the power of helping each other seen among those who live in communities, even among the smallest of the small. We shall, therefore, be pre- pared for the conclusion that both these attainments will be manifested in primaeval man whose origin lies among the great class of mammals. Our means of determining the condition of mankind in this respect are, in the first place, our knowledge of the period of childhood in human beings, and in the second, our knowledge of the life of savage peoples at the present time. Of course the human child can only be considered in regard to this matter when it has outgrown the period of infancy, and has attained to the powers of speech, and of the free use of its limbs. Even then it is in some matters quite helpless and de- pendent on the goodwill of its surroundings. But it soon begins to feel for others' misfortunes. The sight of its mother's tears makes it unhappy ; the cries of its brothers or sisters when in pain call forth sympathetic weeping, and soon the dormant social instinct awakes within it and compels it to take the liveliest interest in the pains of other children or adults. In a few years the child gains some knowledge of what is done by others in these and other cases of internal or external disease, and the desire to follow the example of its elders arises in the heart of the little Samaritan. We need only watch a child at play to notice how it will try to soothe a crying infant with a helpful word, how it will stroke and rub the bruised foot of another who has fallen down, or attempt to staunch the bleeding wound of a third with a handkerchief soaked in cold water. All this has been learnt from its elders. We must therefore, if we are to find the still remoter origin of therapeutics, find out what the adult man in the savage state can do for internal or external pains. And here we are on the right path, for the unanimous testimony of all travellers and investigators tells us that savages must be looked upon as nothing more than big, simple-minded children. As there are now in existence such tribes as the Xingus in Brazil which, left behind in the march of civilisation, are still living in the Stone Age, we may rightly conclude that the methods of healing now obtaining among these are the same as those which were practised by prehistoric palaeolithic man. APPENDIX 449 The commonest lesions from which savage people suffer are those produced by external injury in the course of hunting or fishing, during their wanderings over hill and dale and their feuds with neighbouring tribes. Minor injuries are treated by the patients themselves ; small wounds, and also those made by snake bites, are sucked and then tied up with leaves and strips of bark. Thorns, stings, splinters of wood and other substances are withdrawn with the finger — simple accomplishments in which primitive man does not differ much from the higher animals, such as apes. But a stage of human therapeutics much more developed than that of the animals may soon be observed. Setting of fractures and dis- locations and the opening of the larger abscesses even with the most primitive instruments cannot be done by the patient him- self, but require the help of another. This second party was at first the nearest and closest friend, but later with the further growth of social impulses the practice of therapeutics came into the hands of specially skilled persons, the so-called medicine- men ; which fact tended more and more to the development of their surgical resources and their knowledge of the medicinal properties of certain plants. In the following brief account of obstetrics it will be seen that in this department of therapeutics a vast difference is noticeable between man and animals. Mammals, who alone need be considered, have a specific advantage over man in the roomy construction of their pelves, which renders difficult labour one of the rarest events among wild animals. If such a case occurs, however, the female animal is abandoned, as neither herself nor any comrade of the same species can afford her the necessary assistance. " Parturition," says Brehm, " is nearly always rapid and easy, and takes place without the help or sympathy of any other creature." The opening of the mem- branes and the division of the cord are managed by the mother herself, and Brehm only quotes one doubtful instance in which a domestic cat is said to have bitten through the cord of the kittens of another young cat. Among even the most primitive men the conditions are quite different. If labour is difficult, all the neighbours assemble to give counsel and help. And when medicine-men have been evolved in a tribe, they step into the breach often with the most 29 450 APPENDIX astounding hardihood. Bartels mentions an account by an eye- witness of a successfully performed Caesarian section done by a medicine-man in Uganda (Central Africa) on a primipara, aged twenty years. The evolution of a certain class of special healers among the members of a tribe is what constitutes the great difference be- tween human and animal therapeutics. Savage races can understand external wounds and the dangers of parturition, but they are entirely ignorant of all in- ternal disorders, and their ideas as to their causation are pure guess-work. Demons of all kinds, magicians and witches, the evil eye, worms and other creeping things were regarded as the origin of internal disorders. Nor did the medicine-men know what were the exciting causes of disease. They concealed their ignorance by noisy rattling of drums, by exorcisms and spells ; but even they understood how to employ water in various ways, and how to prepare powerful drugs from plants known to them- selves alone. Among the civilised peoples of to-day we can still see rem- nants of the infancy of the nations in that form of medical art which still flourishes quietly among the peasantry. The savage races are now at the same point of development as regards thera- peutics as were the forefathers of our own civilised peoples. The most ancient systems employed blood, spittle, urine and even excrement, as drugs ; but sympathy also, and the power of the spoken word can be seen deeply ingrained in the old art of the medicine-man. While the popular medicine was thus pro- longing its clandestine existence, civilised therapeutics had developed into a special branch of human knowledge. The foundations were laid in the priestly schools of medicine of Egypt and Mesopotamia ; in the ancient schools of Greece, and in Alexandria, Byzantium and Rome it developed into a still fuller life ; with this development and fruition the mediaeval scholiasts were contented, but the Renaissance brought into the realm of therapeutics new life and new developments. Men of undying name entirely reconstructed anatomy and physiology, and laid new foundations for the healing art in the more accurate knowledge of the structure and behaviour of the human body. Chemistry and the microscope became associated as axillary to medicine, and the joyful plaudits of the people accompanied the discoveries of the learned. From the second half of the six- APPENDIX 451 teenth century, and throughout the seventeenth and eighteenth, one can watch the gradual accumulation of therapeutic know- ledge and skill, growing like the growth of a crystal. The eighteenth century closed with the highly significant discovery by Jenner of protective vaccination against small-pox, by means of which it at last became possible to quell one of humanity's most terrible plagues. This was, as it were, a foretaste of the many blessings which the nineteenth century, so fertile in discoveries, was to bring to suffering humanity. First the discovery of the cell by Schwann and Schleiden ; then the pos- sibility of painless operations by the aid of chloroform ; Pasteur's discovery of the minute living things which induce putrefaction and the morbid infection of the body; following on this Lister's antiseptic system for the treatment of wounds ; Koch's discovery of the bacillus of cholera and tuberculosis, and the possibility of obtaining pure cultures of micro-organisms ; Behring's introduc- tion of the anti-diphtheritic serum, and Rontgen's discovery of the marvellous rays which can pass through solid bodies. Truly we have here, in a single century, such a collection of thera- peutic discoveries of prime importance as exceeds those of all like periods put together. Thousands of sick people who would in earlier times have succumbed to their diseases leave the hospitals cured, and still thousands of doctors are hard at work discovering new remedies for stricken man. If to the many other specific human characteristics we are yet to add another, surely it must lie in the knowledge of the causes of disease, and in this never-resting search for new methods whereby the sufferings of unnumbered sick ones may be alleviated or entirely extinguished. 29 * INDEX. ABORTION, 431. Absorption, intestinal, 220. Accommodation, ocular, 242. Actinomycosis, 397, 407. Addison's disease, 417. Affection, 286, 296. — parental, 305. Agglutinins in blood, 206. Alimentary canal, length of, 216. — system, 118, 214. — diseases, 407, 418. Allantois, 228. Alphabet, 367. Alveoli, 117. Amnion, 228. Anaemia, 416. Anal sac, 107. Anatomy, comparative, 52. Ancestors of man, 26. Anger, 287. Animals, training of, 339. Animism, 309. Anthrax, 397. Anthropoid apes, 16, 27. Ants, 339. Apes, anthropoid, 16, 27. — fossil, 29. Aphides, 339. Arteries, 108. Arts, 313. Auditory organs, 183, 248. BARTHOLIN'S glands, 146. Beauty, sense of, 346. Bile, 218. Bladder, 138. Blastula, 227. Blood, 205. — diseases, 416. — pressure, 204. Blumenbach, types of man, 21. Boats, 337. Bones, 52. — diseases, 410, 425. Brachycephaly, 57. Brain, 152, 234. — chemical composition, 234. — weight of parts, 159. whole, 167, 234. Breasts. See Mammae. Bronchioles, 117. Bronze Age, 325. Buccal mucosa, 122. CJECUM, 130. Cancer, 399, 400. Carving, 350. Castration, 422. Cave dwellings, 44, 333. Cerebellum, 159. Chest. See Thorax. Chin, 61. Cholera, 390, 400. Chorion, 228. Circulatory system, 107, 203. — diseases, 408. Clavicle, 70. Clothes, 330. Coagulation time of blood, 206. Coccygeal gland, no. Colour perception, 247. Communities, 295. Consciousness, 270. Consonants, 277. Contempt, 288. Contentment, 282. Convolutions, cerebral, 154. Cornea, 175. Corpora Arantii, 203. Corpus callosum, 160. Corpuscles, blood. See Erythrocyte, Leucocyte. Coughing, 214. Counting, 272. Cowper's glands, 145. Creation of man, i. Crying, 285. Curiosity, 271. Cutaneous muscle, 202. DANCING, 283. Darwin, 14, 25, 65, 76, 98, 259, 269, 297, 381, 385, 389. Darwinian tubercle, 187. Deformities, 381. — pelvic, 439. Degenerations, 377. Dejection, 284. 453 454 INDEX Deliberation, 270. Demiurges, animal, i. — human, 2. Diabetes, 416. Diet, 214. Digestion, biliary, 218. — buccal, 216. — gastric, 217. - intestinal, 220. — pancreatic, 219. Diluvial man, 39, 46. Diphtheria, 392. — of fowls, 393. Dislocations, 424. Dolichocephaly, 57. Drawing, 349. Dread, 285. Drum, 360. Dwarfs, 379. Dwellings, 333. Dysentery, 395. EAR, 183, 248. — diseases of, 426. Earthenware, 326. Ejaculatory ducts, 147. Emotions, 255, 282. Enteric fever, 391, 400. Envy, 287. Equilibration, 193, 197. Erythrocytes, 112, 113. — destruction, 207. — formation, 207. Evolution, beginnings of theory, 13. Expression of emotions, 282. Eye, 174, 241. — diseases of, 426. Eyebrows, 101. FACIAL angle, 62. — expression, 282, 289. — muscles, 89. Fecundity, 231. Femur, 78. Fermentation, intestinal, 220. Fetish worship, 309. Fibula, 80. Fields, 342. Fingers, supernumerary, 386. Fire, production of, 313. Flint implements, 318. Food, 214. Foot, 81. Foot-and-mouth disease, 397. Fossil apes, 29. Fractures, 425, 449. Friendship, 296. Fright, 285. GAIT, 196. Gangrene, 377. Gardens, 342. Garner, 272, 278. Gaseous exchange, 210. — excretion of skin, 202. Gastric digestion, 217. — juice, 217. Gastrula, 227. Generative organs, 140, 222. diseases of, 410, 421. Giants, 378. Gills, 114, 209. Glanders, 397. Goitre, 420. Gonorrhoea, 395. Gout, 417. Grief, 285. HAECKEL, 15, 24, 30, 258, 268, 290. Hasmogenesis, 207. Haemoglobin, 206. Haemolysins in blood, 206. Haemolysis, 207. Hair, 96. — shedding of, 201. Hairy men, 99, 388. Hand, 76. Handicrafts, 317. Hawking, 214. Heart, 107, 203. Heart-beat, frequency, 204. Heat, bodily, 211. — loss, 213. — production, 212. Heel, 81. Hermaphrodites, 383. Hernia, 419. Hieroglyphics, 363. Hip, 195. Histology, comparative, 52. Homosexuality, 384. Horticulture, 342. Humerus, 75. Huts, 333. Huxley, types of man, 22. Hymen, 145. Hypnotism, 238. Hypophysis cerebri, 162, 208. IDEATION, 266. Idols, 311. Immortality, 309. Immunity, 400. Impulses, 291. — social, 295. Infective diseases, 390. Inflammation, 377. Influenza, 393. Inguinal folds, 107. Instinct, 291. Intermaxilla, 59. Internal secretions, 208. Intestine, 119, 128. — absorption in, 220. INDEX 455 Intestine, fermentation in, 220. Intoxications, 404. Iron Age, 325. JEALOUSY, 287. Joints, 194. Judgment, 270. KIDNEYS, 134. Kissing, 286. Knee, 80, 194. LACHRYMAL glands, 178. Lake dwellings, 336. Larynx, 115, 211. Laughter, 283. Leaping, 198. Leibnitz, 6. Length of life, 191. Leprosy, 392. Leucha^mia, 416. Leucocyte, 112, 113. Lids, 176, 177. Lieberkuhn's glands, 129. Lips, 105. Liver, 131. Loathing, 288. Lungs, 115, 116. Lymph circulation, 208. MACULA lutea, 244. Malar bone, 60. Malaria, 398. Malignant disease, 399, 400. Malta fever, 394. Mammae, 106. — supernumerary, 387. Man, ancestors, 26. — diluvial, 39, 46. — distribution, 19. — mesolithic, 48. — neolithic, 49. — pleistocene, 33. - pliocene, 33. — quaternary, 39. — species, 24. — tertiary, 33. Marriage, 297. Mastication, 216. Maxillary joint, 60. Measuring, 272. Memory, 268. Meningitis, 395. Menstruation, 223. Mental diseases, 413. Mesolithic stratum, 48. Metals, discovery of, 323. — work in, 353. Migration, 302. Milk, 231. Mind, 256. — ontogeny, 263. Mind, phylogeny, 264. Modesty, 307. Mongolian spots, 104. Monogamy, 297. Monsters, 387. Moon worship, 312. Morality, 305. Mosaic tradition of creation, 5. Miiller, types of men, 23. Mumps, 407. Muscles, 83, 192. — diseases, 410. — injuries, 424. — work, 195. Music, 355. Mycetoma, 398. NAILS, 102. Narcotic poisons, 405. Nasal bones, 159. Navigation, 337. Neck, 68. Nematodes, 401. Neolithic man, 49. Nerves, 233. Nervous system, 149, 232. diseases of, 411. Nose, 178, 239. — serous cutaneous glands of, 107. OBESITY, 417. (Esophagus, 125. Olfactory nerve-endings, 180. — physiology, 238. Ontogeny of mind, 263. Orbital cavity, 58. Organic sensations, 255. Ornament, love of, 346. Os calcis, 81. — centrale, 75. Ovary, 142. Ovum, 224. — fertilisation, 227. PAINTING, 349. Pancreas, 133, 219. Pancreatic juice, 219. Parasites, external, 403. — internal, 401. Parathyroids, 208. Parental affection, 305. Parturition, disorders of, 433, 449. — pelvis and, 438. Pathology, comparative, 375. — special, 390. Patriotism, 302. Pelvis, 72. — deformities of, 439. — parturition and, 438. Penis, 144. Perineum, injuries, 441. Perlsucht, 392. 456 INDEX Pernicious anaemia, 416. Perspiration, igg. Pertussis, 393. Peyer's patches, 129. Phylogeny of mind, 264. Physiology, comparative, 189. Pigmentation, cutaneous, 103. Pile dwellings, 336. Pineal gland, 162. Pit dwellings, 335. Pituitary gland, 162, 208. Placenta, 229. Plague, 391, 400. Pleistocene man, 33. Pliocene man, 33. Pneumonia, 394. Poisons, 404. Polar cells, 227. Polyandry. See Marriage. Polygamy. See Marriage. Pottery, 327, 353. Precipitins in blood, 206. Pregnancy, disorders, 429. — duration, 230. - multiple, 433. Presentations, breech, 437. — face, 436. — transverse, 438. Prostate, 146, 226. Psittacosis, 397. Psychology, comparative, 256, 370. — special, 266. Puberty, 222. Pyogenic cocci, 394, 418. QUATERNARY man, 39. Quotient, respiratory, 210. RABIES, 397, 414. Radius, 75. Reason, 270. Reckoning, 272. Religion, 308. Reproductive system, 140, 222, 410, 421. Respiration rate, 209. Respiratory exchange, 210. — movements, 210. — organs, 113, 209. — — diseases of, 408, 420. — quotient, 210. Retina, 176, 241, 246. Rheumatism, acute, 394. Ribs, 69. Rutting, 223. SALIVA, 216. Salivary glands, 124. Salt, 345. Scapula, 70. Scarlet fever, 397. Scorn, 288. Sebaceous secretion, 200. Self-consciousness, 270. Semen, 225. Sense organs, 171, 238. Sexes, proportion of, 230. Sexual perversions, 384. Shoulder, 195. Sinus hairs, 102. Skeleton, 192. Skin, 95, 199. — diseases of, 417. — transpiration through, 202. Skull, 53. Slavery, 303. Sleep, 237. Smallpox, 396, 400. Smell, organs of, 178, 238. Snake poison, 405. Sneezing, 214. Sniffing, 214. Snorting, 214. Sobbing, 286. Social impulses, 295. Song, 355. Species of mankind, 24. Speech, 275. Spermatozoa, 225. Spinal cord, 233. — deformities, 424. Spine, 66. Spinning, 331. Spirillar fever, 393. Spleen, in. Spots, Mongolian, 104. Staphylococci, 394, 418. Statuary, 353. Sternum, 70. Stomach, 126. — digestion in, 217. Stone Age, 317. Streptococci, 394, 418. Stringed instruments, 361. Suicide, 376. Sun worship, 312. Supernumerary breasts, 387. — fingers, 386. — toes, 386. Suprarenal glands, 171, 208. Sweat, 199. Swimming, 198. — membrane, 103. Sympathetic system, 171, 233. Sympathy, 304. Syphilis, 395, 400. TACTILE organs, 171. — sense, 252. Tail, 72. Tailed men, 386. Taming of animals, 339. Tanning, 330. Tapeworms, 402. Taste organs, 180, 251. INDEX 457 Tears, 285. Teeth, 64. Temperature, bodily, 212. — sense, 254. Terramara, 337. Tertiary man, 33. Tetanus, 393. Therapeutics, comparative, 443. Thorax, 6g. Throat sacs, 115. Thumb, 77, gi. Thymus, 118. Thyroid gland, 118, 208. Toes, supernumerary, 386. Tongue, 122. — tactile organs in, 173. — taste organs in, 180. Tonsils, 121. Tools, 317. Totemism, 9, 299, 308. Trematodes, 402. Trypanosoniasis, 398. Tuberculosis, 391, 400. Turkheim, 262, 267, 270, 271, 287, 293. URINARY organs, 134, 221. — diseases, 409. Urine, 221. Uterus, injuries. See Parturition. — masculinus, 147. VASCULAR system, 107, 203. Veins, no. Venereal diseases, 395, 400. Vermiform appendix, 130. Vertebral column, 66. Vesiculae seminales, 148, 226. Vision, 241. - acuity, 243. — colour, 247. — field, 245. — organs of, 174. Vomiting, 218. Vowels, 277. WAR, 303. Weapons, 317. Weaving, 331. Webbed fingers, 382. Weighing, 272. Whooping cough, 393. Will, 290. Wind instruments, 360. Wolffian bodies, 136. Wounds, 418, 444. Writing, 362. Wundt, 257, 289, 291, 371. YAWNING, 214. Yellow fe\rer, 399, 400. ABERDEEN: THE UNIVERSITY PRESS EVOLUTION, ANTHROPOLOGY, ETC. DESIGN IN NATURE: Illustrated by Spiral and other arrange- ments in the Inorganic and Organic Kingdoms as exemplified in Matter, Force, Life, Growth, Rhythms, etc., especially in Crystals, Plants and Animals. With Examples selected from the Reproductive, Alimentary, Respiratory, Circulatory, Nervous, Muscular, Osseous, Locomotory and other Systems of Animals. By J. BELL PETTIGREW, M.D , LL.D., F.R.S., F.R.C.P., Laureate of the Institute of France, late Chandos Professor of Anatomy and Medicine in the University, St. Andrews. Illustrated by nearly 2,000 Figures, largely original and from nature. In 3 vols. 4to, 63s. net. THE ORIGIN OF VERTEBRATES. By WALTER H. GASKELL, M.A., M.D. (Camb.), LL.D. (Edinburgh and McGill Univ., Montreal), etc. With 168 Illustrations. Medium 8vo, 21s. net. THE STORY OF CREATION : a Plain Account of Evolution. By EDWARD CLODD. With 77 Illustrations. Crown 8vo, 3s. 6d. A PRIMER OF EVOLUTION : being a Popular Abridged Edition of " The Story of Creation ". By EDWARD CLODD. With Illus- trations. Fcp. Svo, Is. 6d. THE OLD RIDDLE AND THE NEWEST ANSWER: an Enquiry as to how far Modern Science has altered the aspect of the Problem of the Universe. By JOHN GERARD, S.J., F.L.S. Crown Svo, 2s. 6d. net. Popular Edition, sewed, 6d. %* The book is a reply to Haeckel's "The Riddle of the Universe ". THE SECRET OF THE TOTEM. By ANDREW LANG. Svo, 10s. 6d. net. WORKS BY Q. J. ROMANES. AN EXAMINATION OF WEISMANNISM. Crown Svo, 6s. DARWIN AND AFTER DARWIN : an Exposition of the Darwinian Theory, and a Discussion on Post-Darwinian Questions. PART I. THE DARWINIAN THEORY. With Portrait of Darwin and 125 Illustrations. Crown Svo, 10s. 6d. PART II. POST-DARWINIAN QUESTIONS : Heredity and Utility. With Portrait of the Author and 5 Illustrations. Crown Svo, 10s. 6d. PART III. POST-DARWINIAN QUESTIONS: Isolation and Physiological Selection. Crown Svo, 5s. QUERIES IN ETHNOGRAPHY. By ALBERT GALLOWAY KELLER, Ph.D., Assistant Professor of the Science of Society in Yale University. Fcp. Svo, 2s. net. THE ORIGIN OF CIVILISATION, and the Primitive Con- dition of man. By Lord AVEBURY. With 6 Plates and 20 Illustrations. Svo, 18s. LONGMANS, GREEN, AND CO., 39 Paternoster Row, London, E.C. ; New York, Bombay, and Calcutta. sj*!*^^ i UNIVERSITY OF TORONTO LIBRARY Do not remove the card from this Pocket. Acme Library Card Packet Under Pat. "Ref. Index File." Made by LEBEAEY BUEEAU, Boston ight