Part 2
III. Respiratory Organs 243 1. Nasal Cavity 243 2. Larynx 246 Cartilages of the Larynx 247 Muscles of the Larynx 249 3. Trachea 251 4. Lungs 252 Thyroid Gland 254 Thymus Gland 254
IV. Urogenital System 255 1. Excretory Organs 255 Kidneys 255 Ureter 256 Bladder 256 (Suprarenal Bodies) 257 2. Genital Organs 257 _A._ Male 257 _B._ Female 263 Muscles of the Urogenital Organs, Rectum, and Anus 268 _a._ Muscles Common to the Male and Female 268 _b._ Muscles Peculiar to the Male 271 _c._ Muscles Peculiar to the Female 272
THE CIRCULATORY SYSTEM 274
I. The Heart 274
II. The Arteries 280 1. Pulmonary Artery 280 2. Aorta 281 _A._ Thoracic Aorta and its Branches 281 Common Carotid Artery 283 Subclavian Artery 290 _B._ Abdominal Aorta and its Branches 301 External Iliac Artery and its Branches 309
III. The Veins 315 1. Veins of the Heart 315 2. Vena Cava Superior and its Branches 316 Veins of the Brain and Spinal Cord 324 3. Vena Cava Inferior and its Branches 325 Portal Vein 326
IV. Lymphatic System 330 1. Lymphatics of the Head 331 2. Lymphatics of the Neck 332 3. Lymphatics of the Thoracic Limbs 332 4. Lymphatics of the Thorax and Abdomen 333 5. Lymphatics of the Pelvic Limbs 334
THE NERVOUS SYSTEM 335
I. The Central Nervous System 336 1. Spinal Cord 336 2. The Brain 339 (1) Myelencephalon 344 (2) Metencephalon 347 (3) Mesencephalon 351 (4) Diencephalon 352 (5) Telencephalon 357
II. The Peripheral Nervous System 369 1. Cranial Nerves 369 I. Olfactory Nerve 369 II. Optic Nerve 369 III. Oculomotor Nerve 369 IV. Trochlear Nerve 370 V. Trigeminal Nerve 370 VI. Abducens 375 VII. Facial Nerve 375 VIII. Auditory Nerve 377 IX. Glossopharyngeal Nerve 378 X. Vagus Nerve 378 XI. Accessory Nerve 382 XII. Hypoglossal Nerve 383 2. Spinal Nerves 383 _A._ Cervical Nerves 383 The Brachial Plexus 386 _B._ Thoracic Nerves 393 _C._ Lumbar Nerves 394 Lumbar Plexus 395 _D._ Sacral Nerves and Sacral Plexus 399 _E._ Nerves of the Tail 404 3. Sympathetic System 404
SENSE ORGANS AND INTEGUMENT 409
I. The Eye 409
II. The Ear 415
III. Olfactory Organ 426
IV. Organ of Taste 426
V. Integument 427
APPENDIX: PRACTICAL DIRECTIONS 429
INDEX 473
LIST OF ILLUSTRATIONS.
FIG. PAGE
1. Skeleton 2 2. Fourth Thoracic Vertebra 3 3. Fourth Thoracic Vertebra 3 4. Thoracic Vertebræ 5 5. Lumbar Vertebræ 7 6. Sacrum 9 7. Sacrum 9 8. Caudal Vertebra 11 9. Caudal Vertebra 11 10. Cervical Vertebræ 12 11. Sixth Cervical Vertebra 13 12. Atlas 13 13. Axis 15 14. Ligaments of the Odontoid Process 18 15. Rib 19 16. Sternum 20 17. Occipital Bone 22 18. Occipital Bone 22 19. Interparietal 25 20. Sphenoid 25 21. Presphenoid 29 22. Temporal 31 23. Temporal 31 24. Tympanic Bulla 33 25. Petrous Bone 34 26. Frontal 37 27. Maxillary Bone 39 28. Maxillary Bone 39 29. Premaxillary 41 30. Nasal 42 31. Ethmoid and Vomer 43 32. Ethmoid and Vomer 43 33. Palatine 45 34. Lachrymal 46 35. Malar 46 36. Mandible 48 37. Mandible 48 38. Hyoid 49 39. Skull, Dorsal Surface 50 40. Skull, Side View 53 41. Skull, Ventral Surface 55 42. Cavities of Skull 57 43. Skull, Median Section 60 44. Scapula 62 45. Scapula 62 46. Clavicle 64 47. Humerus 65 48. Humerus 65 49. Radius and Ulna 68 50. Radius and Ulna 68 51. Bones of the Hand 70 52. Ligaments of the Elbow 74 53. Ligaments of the Elbow 74 54. Innominate Bone of Kitten 76 55. Innominate Bone 77 56. Femur 79 57. Tibia and Fibula 81 58. Bones of the Foot 83 59. Calcaneus 83 60. Knee-joint 89 61. Knee-joint 89 62. Muscles of the Skin 94 63. Muscles on Dorsal Side of Head 97 64. Muscles of Face 102 65. Ventral Muscles of Thorax, Neck, and Head 109 66. Pterygoid and Palatal Muscles 112 67. Muscles of Tongue, Hyoid, and Pharynx 114 68. First Layer of Body Muscles 117 69. Deep Muscles of the Vertebræ and Ribs 125 70. Dorsal Muscles of Lumbar and Caudal Regions 127 71. Deep Muscles of Neck 135 72. Muscles on the Ventral Surface of the Cervical Vertebræ 143 73. Second Layer of Body Muscles 149 74. Diaphragm 152 75. Lateral Muscles of Arm 158 76. Origin of Lateral Muscles on Scapula 160 77. Medial Muscles of Arm 162 78. Origin of Medial Muscles on Scapula 163 79. Deep Medial Muscles of Arm 167 80. Deep Lateral Muscles of Arm 169 81. Areas of Origin of Muscles on Ventral Surface of Humerus 171 82. Areas of Origin of Muscles on Medial Side of Humerus 171 83. Areas of Origin of Muscles on Dorsal Surface of Left Humerus 171 84. Tendons on Back of Hand 175 85. Deep Muscles of Forearm 177 86. Insertions of Muscles on Radius and Ulna 178 87. Insertions of Muscles on Radius and Ulna 182 88. Mm. Lumbricales, etc. 183 89. Deep Muscles of Palm of Hand 184 90. Lateral Muscles of the Leg 192 91. Medial Muscles of the Leg 197 92. Deep Medial Muscles of Thigh 200 93. Teeth of the Upper Jaw 225 94. Teeth of the Lower Jaw 226 95. Tongue, Epiglottis, etc. 227 96. Muscles of Tongue, Hyoid, and Pharynx 229 97. Stomach 235 98. Colon and Cæcum 238 99. Ileocolic Valve 238 100. Liver 240 101. Liver 240 102. Pancreas and Spleen 242 103. Cartilages of Nose 244 104. Cartilages of Larynx 247 105. Muscles of Larynx 250 106. Bronchi 253 107. Thymus Gland 254 108. Kidney 255 109. Section of Kidney 255 110. Testis 260 111. Male Genital Organs 262 112. Female Urogenital Organs 265 113. Muscles of Urogenital Organs and Anus in Male 270 114. Muscles of Urogenital Organs of Female 272 115. Heart 276 116. Heart 276 117. Inside of Heart 278 118. Vessels of Thorax 282 119. Common Carotid and Internal Jugular 284 120. Branches of External Carotid 288 121. Arteries of Brain 291 122. Vessels and Nerves of the Axilla 295 123. Vessels and Nerves of the Arm 299 124. Palmar Arch 301 125. Cœliac Artery 302 126. Abdominal Blood-vessels 305 127. Medial Vessels and Nerves of the Leg 310 128. Deep Arteries of Foot 314 129. Thoracic Blood-vessels 317 130. Superficial Vessels and Nerves of the Forearm 319 131. Blood-vessels of the Face 322 132. Portal Vein 327 133. Spinal Cord, cranial portion 336 134. Section of Spinal Cord 337 135. Origin of Spinal Nerves 337 136. Cauda Equina, etc. 338 137. Brain, Dorsal View 340 138. Brain, Ventral View 342 139. Diagram of Brain 343 140. Diagram of Brain 343 141. Dorsal View of Midbrain and ’Tween-brain 350 142. Ventral View of Midbrain and ’Tween-brain 352 143. Longitudinal Section of Brain 356 144. Lateral View of Brain 358 145. Diagram of Sulci and Gyri 359 146. Diagram of Sulci and Gyri 361 147. Corpus Callosum 363 148. Fornix, Hippocampus, and Corpus Striatum 364 149. Transverse Section of Brain 366 150. Transverse Section of Brain 366 151. Transverse Section of Brain 366 152. Transverse Section of Brain 367 153. Transverse Section of Brain 367 154. Cranial Nerves 374 155. Nerves of Face 376 156. Cranial Nerves in the Neck 379 157. Sympathetic and Vagus in the Thorax 381 158. Nerves of the Neck 384 159. Brachial Plexus 387 160. Nerves and Vessels of Axilla 389 161. Nerves and Vessels of Forearm 391 162. Lumbar and Sacral Nerves 398 163. Great Sciatic Nerve 401 164. Sympathetic and Vagus in Abdomen 407 165. Nictitating Membrane 410 166. Muscles of Eyeball 411 167. Diagram of Eye 413 168. Cartilage of External Ear 417 169. Muscles of External Ear 419 170. Tympanic Membrane 422 171. Malleus and Incus 423 172. Stapes 424 173. Membranous Labyrinth 425
ANATOMY OF THE CAT.
THE SKELETON OF THE CAT.
The skeleton of the cat consists of 230 to 247 bones exclusive of the sesamoid bones (44) and the chevron bones (8). These are divided as follows: head 35-40, vertebral column 52-53, ribs 26, sternum 1-8, pelvis 2-8, upper extremities 62, lower extremities 54-56. The number of bones varies with the age of the individual, being fewer in the old than in the young animal, owing to the fact that in an old animal some bones that were originally separate have united.
I. THE VERTEBRAL COLUMN. COLUMNA VERTEBRALIS.
The vertebral column, spinal column, or back-bone, consists of a varying number of separate bones, the vertebræ. At its cranial end are seven vertebræ (=cervical=, Fig. 1, _c_) which are without ribs and support the head; caudad of these are thirteen rib-bearing vertebræ (=thoracic=, Fig. 1, _m_); caudad of these are seven that are again without ribs (=lumbar=, Fig. 1, _o_); these are followed by three vertebræ (=sacral=, Fig. 1, _x_) which are united into a single bone, the =sacrum=, which supports the pelvic arch. Following the sacral vertebræ are twenty-two or twenty-three small ribless vertebræ which support the tail (=caudal=, Fig. 1, _y_).
=Thoracic Vertebræ.= =Vertebræ thoracales= (Fig. 4).--The =thoracic vertebræ= are most typical, and the fourth one of these may therefore be first described (Figs. 2 and 3). It forms an oval ring which has numerous processes and surrounds an opening which is the vertebral foramen (_a_). The ventral one-third of this ring is much thickened and forms the =centrum= or body (=corpus=) (_b_) of the vertebra. The centrum is a semicylinder, the plane face of which bounds the vertebral canal, while the curved surface is concave longitudinally and is directed ventrad. The dorsal plane surface of the centrum is marked by a median longitudinal ridge on either side of which is an opening (nutrient foramen) for a blood-vessel. The ends are nearly plane, the caudal being slightly concave; they are harder and smoother than the other surfaces. They may be easily separated in a young specimen as thin plates of bone known as =epiphyses=.
At the caudal end of the centrum, at its dorsolateral angle, is a smooth area on each side continuous with the surface of the epiphysis and bounded dorsolaterally by a sharp ridge of bone (_c_). It is a =costal demifacet=. In corresponding positions at the cranial end of the centrum are two demifacets not limited by bony ridges (_d_). When the centra of two contiguous thoracic vertebræ are placed together in the natural position the cranial costal demifacets of one together with the caudal demifacets of the other form two =costal= facets (Fig. 4, _e_), one on each side, and each receives the head of a rib.
The dorsal two-thirds of the vertebral ring forms the =vertebral arch= which is continued dorsally into the long, bluntly pointed =spinous process= (Figs. 2 and 3, _k_) for attachment of muscles.
The vertebral arch (each half of which is sometimes called a =neurapophysis=) rises on each side from the cranial two-thirds of the dorsolateral angle of the centrum, as a thickened portion, the radix or pedicle (Figs. 2 and 3, _e_), which forms the ventral half of the lateral boundary of the vertebral canal. From the dorsal end of each radix a flat plate of bone, the =lamina= (_f_), extends caudomediad to join its fellow of the opposite side and form the vertebral arch. Owing to the fact that the radix rises from only the cranial two-thirds of the centrum there is left in the caudal border of the vertebral arch a notch bounded by the radix, the lamina, and the centrum. There is also a slight excavation of the cranial border of the radix. When the vertebræ are articulated in the natural position, these notches form the =intervertebral foramina= (Fig. 4, _d_), for the exit of the spinal nerves.
At the junction of radix and lamina the arch is produced craniolaterad into a short process, the =transverse process= (_g_), knobbed at the end. On the ventral face of its free end the transverse process bears a smooth facet, the transverse costal facet or tubercular facet (Fig. 4, _c_), for articulation with the tubercle of a rib.