Subject Index 



855 



Sensor j — {Continued) 



center, primary, 535, 716 



epithelium, 308 



fibers, 140, 160, 171, 184 



nerves, 159, 160 



range of ear, 698 



tracts, 153, 170 

 Seps, 244 

 Septum, dorsal spinal cord, 152 



interorbital, 517 



mediastinal, 21, 22 



transversum, 21 

 Serosa, 241 



Serous glands, 199, 636 

 Serpentes (Ophidia), 486, 488, 489, 490, 



500 

 Serratus magnus (muscle), 92 

 Serum, 329 

 Sesamoid bones, 133 

 Sex(es), 231, 233 



differentiation of, 88 

 Sex-glands, relation to pituitary, 226 



female, 216, 217 



male, 216 

 Sexual development, 226 

 Seymouria, 565 

 Shaft (rachis), 505, 509 

 Shank, 94, 131 



Shark-like fishes (see Fishes, shark-like) 

 Sharks, 11, 26, 46, 49, 51, 53, 58, 64, 87, 

 99, 115, 120, 128, 129, 165, 234, 

 235, 238, 239, 244, 380, 422 

 Sheath, of muscle-spindle, 212 



myelin (medullary), 140, 141, 142, 1S3, 

 319 



non-medullated nerve-fiber, 183 



Schwann's, 140, 319 (see also Neuri- 

 lemma) 

 Sheep, 756, 757 

 Sheepshead, 55 



Shell, 233-235, 236, 238, 240, 241, 245, 

 293; of Chelonia, 494, 495 



membrane, 235, 236 

 Shoulder, 131 



girdle (see Pectoral girdle) 

 Shoulder-blade (see Scapula) 

 Shrew, 736 



tree, 736, 783 

 Siluridae, 433 

 Simiidae, 771 

 Similarities, anatomic, 2 

 Simplicidentata, 742 

 Sinanthropus, 771 

 Sinus venosus, 63, 64, 65, 73 

 Sinus(es), 605 



of Cuvier, 73, 74 



frontal, 199, 605, 677 



lacrimal, 686 



lymph, 66 



maxillary, 605, 677 



paranasal, 677 



sphenoid (al), 605, 677 



urinogenital, 650 



venous, 63, 64, 73, 622 

 Siphonops, 458 



Siren, 452 



Sirenia(n), 571, 762, 763, 781 



Size and survival, 797 



Skate(s), 30, 119, 133, 234, 238, 239, 244, 



417, 422 

 Skeletal tissues, 322-327 

 Skeleton, 101-138, 107, 383, 431, 446, 

 470, 512, 584, 585 



adaptations in, 782 



of amphibians, 446-449 



appendicular, 128-135, 136, 138 



axial, 136-138, 271 



of birds, 115, 122, 128, 133, 511, 512, 

 513-518 



degree of ossification of, 786 



of fishes, 101, 113-115, 122, 125, 126, 

 133, 136, 414, 423, 431 



jaws, of Placodermi, 421 



lateral parietal, 137, 138 



of mammals, 106, 115, 117, 122, 125, 

 126, 128, 561, 581-607 



of man, 103, 106, 109, 114, 122, 130, 131, 

 132 



of the notochordal axis, 137, 138 



pneumaticity of, 522, 523 



of reptiles, 14, 22, 289, 293, 409, 410, 

 467-472, 563 



of the sternal axis, 137, 138 



visceral, 118, 125, 126, 136, 138, 418, 606 



Skin (integument), 17-20, 142, 154, 164, 



165, 166, 171, 172, 193, 194, 195, 



198, 214, 258, 270, 306, 416, 445, 



447, 448, 463 



blood-vessels in, 18 



glands in, 20 



of invertebrates, 17, 18 



of mammals, 573-581 



modifications of, 785, 786 



of palm, 577 



of vertebrates, 18 

 Skull, 112, 115, 116, 117, 118, 119, 120, 

 121, 122, 123, 124-128, 138, 432, 

 449, 468, 469, 490, 500, 501, 516, 

 517, 563, 601, 604, 740, 760 



anapsid, 501, 502 



arches of, 377 



bony, 120-126 



diapsid, 501, 502 



of mammals, 600-607 



parapsid, 501, 502 



platy basic, 517 



position of parts, 376, 377, 378, 379 



shape of, 603, 604 



synapsid, 501, 502, 600 



Taungs, 771 



tropibasic, 517, 600 

 Skunk, 747 

 Sloth, 44 



ground, 778 



three-toed, 743 



tree, 743 



two-toed, 743, 744 

 Smell, 195, 679 



keenness of, 673, 675 



organs of, 116, 195-199, 273 



