Index 



727 



Therapsida, 604, 627 



Thermal changes in muscle, 122 



Thermocline, 661, 662 



Thiamin, 146 



Thirst, 214 



Thoracic basket, 107 



cavity, 129 



cord, 206 



duct, 169, 183 



enlargement, 202 



nerves, 204 



vertebrae, 105, 106, 107 



walls, 155 

 Thorax, 488, 522 

 Thorny-headed worm (see Acantho- 



cephala), 347, 443-445 

 Thrip, 539 

 Thrombin, 179, 180 

 Thrombocyte, 68 

 Thrombokinase, 179, 180 

 Thrombus, 179 

 Thumb, 53 

 Thumps, 432 

 Thymus, 227, 249 

 Thyone, 552, 553 

 Thyroid, 72, 228-231, 597 



cartilage, 150, 151 

 Thyrotropic hormone, 245 

 Thyroxin, 174, 225, 228 

 Thysanoptera, 539 

 Thysanura, 536 

 Tibia, 101, 110. 512, 522, 523 

 Tibio-fibula, 56, 58 

 Tick, 367, 489, 514, 515, 516 

 Tidal air, 156 

 Tiedemann's body, 546 

 Tiger salamander, 596, 597 

 Tinamiformes, 625 

 Tinamou, 625 

 Tissue, 36-38, 266 

 Toad, 46, 130, 166, 197, 567, 596, 599, 



601, 650 

 Toes, 110 

 Tone, muscle (see tonus), 125, 200, 



211 

 Tongue, 53, 61, 77, 108. 130 

 Tongue worm (see Enteropneusta or 



Pentastomida) 

 Tonsil, 178 

 Tonus, 125, 200, 211 

 Tooth, formula, 87-88 



shell (see Dentalium), 466, 468, 469, 

 476 

 Top minnow. 588. 590 

 Tornaria. 557, 558 

 Torpedo. 576, 580, 581 

 Torus. 83 

 Toucan, 625 



Touch, 211,212,213 



organ, 13 

 Trachea of arthropods, 488 



insects, 148, 525 



vertebrates, 151-152, 228 

 Tracheoles, 525 

 Training, 126 



Transplants of embryonic tissue, 294 

 Transverse fission, 449 

 Trap-door spider, 513 

 Trematoda, 404, 409-415 

 Trembley, 390 

 Trial and error, 390 

 Triarthrus, 489 

 Triassic period, 342, 626 

 Tribolium, 536 

 Triceratops, 614 

 Trichechus, 630 



Trichina worm (see Trichinella) 

 Trichinella spiralis, 434-435 

 Trichinosis, 434, 435 

 Trichocyst. 368, 369 

 Trichomonas, 357 

 Trichonympha, 358 

 Trichoptera. 540 

 Trichuris, 435-436 

 Tricuspid valve, 162, 163, 164 

 Tridacna, 471, 476 

 Trilobita. 489, 509-510 

 Trilobite larva, 510 

 Triploblastic, 398 

 Triturus, 596, 598 

 Trivium, 545 



Trochanter, 110, 512, 522, 523 

 Trochophore, 449, 450, 452-453, 465, 



466, 482, 646 

 Trogon, 625 

 Trogoniformes. 625 

 Trombiculid mite, 516 

 Trophic hormones, 244-246 

 Trophoblast, 285, 287 

 Trophozoite. 363, 364, 365 

 Trout, 46, 84 _ 



Truncus arteriosus, 63, 64, 65 

 Trunk fish, 589. 590 

 Trunk of frog, 51 

 Trypanosoma, 357-359, 518 

 Trypsin, 139 

 Trypsinogen, 139. 248 

 Tsetse fly. 358. 536 

 Tuatera, 600, 611, 612 

 Tube feet, 543. 545, 548, 549, 553 

 Tubercle, 53, 107, 158 

 Tuberculosis, 158 

 Tuberosity, 109 

 Tubifex, 449, 462 



Tubule, kidney, 184, 185. 186, 188, 189 

 Tubulidentata, 630, 638-639 

 Tumor, 236, 239 



