INDEX 



819 



Theriodontia, 541. 



Theromorpha, 540. 



Theropoda, 423. 



Theropsida, 371. 



Thoatherium, 703, 781. 



Thread-fish, 250. 



Thrush, 437, 466, 522. 



Thylacinas, 564. 



Thylacoleo, 568. 



Thylacosmilus, 566. 



Thynnus, 250. 



Thyroid gland, actinopterygii, 207. 



elasmobranchs, 164. 



hag-fishes, 124. 



Lampetra, 117. 

 Tiger, 690. 

 Tilapia, 287. 

 Time, 16. 

 Tinamu, 514. 



TlNBERGEN, N., 480. 



Tits, 522. 

 Titanotheres, 730. 

 Tomistorna, 421. 

 Tornaria larva, 56. 

 Torpedo, 182, 254, 258. 

 Tortoiseshell, 373, 393. 

 Toucan, 467. 

 Tongue, actinopterygii, 193. 



amphibia, 342. 



artiodactyls, 744. 



birds, 490. 



elasmobranchs, 158. 



lamprey, 89. 



reptiles, 378, 405, 409. 



ruminants, 743. 



squamata, 405. 

 Touch, amphibia, 350. 



bats, 589. 



birds, 435. 



fishes, 172, 212, 222. 

 Toxodon, 702. 

 Trabecula, 87, 144. 

 Trachinus, 252, 258. 

 Trachodonts, 424. 

 Tragulus, 754. 

 Trawling, 282. 

 Tree-creeper, 521. 

 Tree-shrews, 584. 

 Triassochelys, 390, 395, 398. 

 Tricentes, 683. 

 Triceratops, 426. 

 Trichosurus, 567. 

 Triconodonta, 546. 

 Trigger-fish, 253, 258. 

 Trigla, 211, 237, 250. 

 Trilophodon, 715. 

 Trionyx, 395, 396. 

 Trituberculata, 548. 

 Triturus, 303, 358, 365. 



Tritylodon, 544. 



Trochilus, 520. 



Trochophore larva, 49. 



Troglodytes, 497, 522. 



Trophonemata, 164. 



Trout, 191. 



Trunk fishes, 246, 249, 252, 258. 



Trygon, 162, 164, 182. 



Tuatara, 402. 



Tubulidentata, 704. 



Tunicata, 60. 



Tunicin, 60. 



Tunny, 250. 



Tupaia, 584. 



Turacou, colour, 436. 



Turbot, 265. 



Turdus, 437, 466, 522. 



Turkey, 501, 518. 



Tursiops, 672. 



Turtles, 392. 



Tylopoda, 751. 



Tylosaurus, 409. 



Tylotriton, 332. 



Typhlomolge, 358, 365. 



Typhlonectes, 366. 



Typhlops, 413. 



Tyrannosaurus, 423. 



Tyto, 520. 



Uintatherium, 718. 

 Ultimobranchial gland, 208. 

 Undina, 268. 

 Ungulata, 694. 



Uranoscopus, zit,, 222, 249, 253. 

 Urea, in blood, 162, 341. 

 Uria, 519. 



Uric acid, birds, 474. 

 Urinogenital system, actinopterygii, 

 202. 



amphibia, 340. 



birds, 474. 



chelonia, 397. 



dipnoi, 278. 



elasmobranchs, 162. 



hag-fishes, 124. 



lamprey, 93. 



marsupials, 559. 



monotremes, 553. 



reptiles, 380. 

 Urochordata, 24, 69. 

 Urodela, 361, 364. 

 Urohypophysis, 208. 

 Uromastix, 407. 

 Uropygial gland, 432. 

 Ursus, 685. 

 Uterus, see Placenta. 



Vagina, see Reproduction, Urino- 

 genital system, Fertilization. 



