8l2 



INDEX 



Opisthocomus, 518. 



Opisthonephros, 162. 



Opossum, 563. 



Orang-utan, 626. 



Orcinus, 667. 



Oreodonta, 748, 750. 



Oreopithecus, 632. 



Organization, evolution of, 765, 780. 



earliest chordates, 765. 



mammals, 767. 



vertebrates, 81. 

 Ornithischia, 424. 

 Ornitholestes, 423. 

 Ornithomimus , 423 . 

 Ornithorhynchus, 549. 

 Orogenesis, 13. 

 Orohippns, 736. 

 Orycteropus, 701, 704. 

 Osborn, H. F., 709. 

 Osmoregulation, actinopterygii, 202, 

 208. 



amphibia, 340. 



birds, 474. 



earliest chordates, 124. 



elasmobranchs, 162. 



hag-fishes, 124. 



Lampetra, 93. 



reptiles, 378, 380. 



tunicates, 63. 

 Ostariophysi, 216, 237. 

 Osteolepis, 268, 326. 

 Osteostraci, 81, 125. 

 Ostracion, 246, 249, 252, 258. 

 Otter, 686. 

 Ovary, see Reproduction, Eggs, Sex 



hormones. 

 Ovis, 764. 

 Owl, 482, 489. 

 Oxen, 761. 

 Oxyaena, 684. 



Pachycortnus, 236. 

 Packard, A., 218. 

 Paedomorphosis, 23, 46, 77. 



amphibia, 332, 364. 



dipnoi, 279. 



Lampetra, 120. 



man, 640, 651. 



origin of chordates, 77. 



tunicates, 73. 

 Paenungulata, 706. 

 Palaeanodonta, 594. 

 Palaeodonta, 748. 

 Palaeognathae, 514. 

 Palaeogyrinus, 326. 

 Palaeolithic men, 648. 

 Palaeomastodon, 715. 

 Palaeomeryx, 755. 

 Palaeoniscoidea, 228. 



Palaeospondylus, 186. 



Palaeostylops, 701. 



Palaeotherium, 732. 



Palaeotragus, 758. 



Palate, see Skull. 



Pan, 626. 



Pancreas, actinopterygii, 201. 



amphibia, 343. 



elasmobranchs, 159, 167. 



lamprey, 90. 

 Panda, 686. 

 Pangolin, 601. 

 Pantodonta, 716. 

 Pantolambda, 718. 

 Pantotheria, 548. 

 Papio, 624. 

 Parachordals, 144. 

 Paracirrhites, 250. 

 Paradise, birds of, 500. 

 Parahippus, 736. 



Parallel evolution, see Evolution. 

 Paranthropus, 643. 

 Parapithecus, 625, 632. 

 Parapsida, 391, 399. 

 Parasympathetic system, see Auto- 

 nomic nerves. 

 Parathyroid, 208. 

 Pareiasaurs, 390. 

 Parker, G. H., 41, 259. 

 Parotoid glands, 302. 

 Parr, 205. 

 Parrot, 477. 

 Parrot fish, 252. 

 Partridge, 492, 518. 

 Parns, 521. 

 Passer, 521. 

 Passeriformes, 521. 

 Patagium, 426, 585, 592, 657. 

 Pathogens, effect on evolution, 784. 

 Pavo, 518. 

 Peacock, 500, 518. 

 Pearls, artificial, 243. 

 Peccary, 749. 

 Pecking order, 493. 

 Pecora, 755. 

 Pecten, 484. 



Pectoral girdle, see Fins, Limbs. 

 Pelecaniformes, 517. 

 Pelvic girdle, see Fins, Limbs. 

 Pelycosauria, 540. 

 Penguins, 441, 493, 514. 

 Penis, see Fertilization. 

 Perameles, 560. 

 Perch, 191, 237, 247, 252. 

 Perching, 447. 

 Perdix, 518. 



Pericardio-peritoneal canal, 161. 

 Pericardium, Ciona, 63. 



elasmobranchs, 161. 



