INDEX. 



691 



Ogmius, 369*. 

 Ogmodon, 370-. 

 Ogmorhinus, 6272. 

 Oil-bird, 4722. 

 Oil gland, birds, 419. 

 Okapia, 590 1. 

 Old-wife, 2361. 

 Olecranon, 492. 

 Olfactory lobes, 68. 

 Olfactory organ of Ani- 

 phioxus, 18 ; of fishes, 

 78. 

 Oligodon, 3681. 

 Oligopleuridae, 213. 

 Oligorus, 2351. 

 Oligosarcus, 2172. 

 Olistherops, 238i. 

 01m, 3072. 



Ommatophoca, 6272. 

 Omomys, 653i. 

 Oraost^rnum, 270. 

 Onchorhynchus, 216i. 

 Oneirodes, 246i. 

 Onychodactvlus, 273, 



3061. 

 Onychodectes, 609i. 

 Onychodontidae, 175. 

 Onychogale, 5352. 

 Onvchomys, 634'. 

 Onchus, 147, 262. 

 Opah, 2281. 



Operculum, Amphibia, 

 279, 280 ; Dipnoi, 

 249. 

 Ophicbthus, 225i. 

 Ophichthys, 2231,2251. 



Ophiderpeton, 315i. 



Ophidia, 355. 



Ophidium, 2442. 



Ophiocephalus, 20 1 , 2 1 0, 

 2321. 



Ophiodes, 3512. 



Ophiodon, 242'. 



Ophiognomon, 3522. 



Ophiomorus, 354i. 



Ophiops, 3532. 



Ophiopsis, 180. 



Ophiopsiseps, 3542. 



Ophioscion, 2352. 



Ophisaurus, 3512. 



Ophryoessa, 3511. 



Ophrysia, 4652. 



Ophthalmic ganglion, 

 135. 



Ophthalmicus profun- 

 dus, 73, 135. 



Ophtlialmo saurus, 395i. 



Opisthocoelous, 161, 

 317. 



Opisthocomus, 4661. 

 Opisthoglypha, 3682. 

 Opisthognathtis, 2352. 

 Opisthomi, 245'. 

 Opisthonema, 2142. 

 Opisthopterus, 2142. 

 Opisthotropis, 3671. 

 Opossum, 5391. 

 Opsanus, 244^. 

 Opsariichthyp, 220'. 

 Optic chiasma, 69. 

 Optic lobes, 67. 

 Optic thalami, 69. 

 Optic vesicles, 68. 

 Or. = Oriental. 

 Oral cirri, 11, 19. 

 Oral hood, 19. 

 Orang-utan, 66II. 

 Orca, 5632. 

 Orcella, 5632. 

 Orcynus, 2382. 

 Oreas, 591 1. 

 Oreinomys, 6332. 

 Oreinus, 219'. 

 Oreobatrachus, 3131. 

 Oreodon, .57.", 585i. 

 Oreonectes, 221'. 

 Oreophasis, 465". 

 Oreophrynella, 312i. 

 Oreopithecus, 659i. 

 Oreopsittacus, 4702. 

 Oreosaurus, 3522. 



Oreosoma, 240'. 



Oreotragus, 5902. 



Orestias, 227i. 



Oriole, American, 4781, 

 golden, 4771. 



Oriolus, 4771. 



Ornithochirus, 3902. 



Ornithodelphia, 525. 



Ornithopoda, 386. 



Ornithochvnchus, 490, 

 494, 529, o2G. 



Ornithoscelida, 383. 



Ornithosuchus, 3821. 



Orodus, 1511. 



Orohippus, 599i. 



Oronasal groove, 120. 



Ortalis, 465i. 



Orthacodus, 152i. 



Orthagoriscus, 92, 183, 

 198, 195, 223, 2472. 



Orthodon, 220'. 



Orthognathism, 489. 



Orthopoda, 386. 



Orthopristis, 236'. 



Orthostichous, 56. 



Orthostomus, 241 1. 



Orycteropus, 542, 549i. 



Oryx, 5911. 

 Oryzomys, 6341. 

 Oryzoryctes, 641'. 

 Os cloacae, 3 12. 

 Os coccygis, 265. 

 Os cines, 475. 

 Os innomiuatnin, 491. 

 Osmerus, 208, 216'. 

 Os penis, 515. 

 Osphromenus, 2371. 

 Os planum, 486. 

 Osprey, 464i. 

 Osseous tissue of Elas- 



mobranchii, 122. 

 Ostariophvsi, 2162. 

 Osteobrama, 2202. 

 OsteochUus, 2192. 

 O.steoderms, 317, liz- 

 ards, 337. 

 Osteogeniosus, 2212. 

 Osteoglossum, 215i. 

 Osteolaemus, 3832. 

 Osteolepis, 175. 

 Osteostraci, 261. 

 Ostracion, 24'fi, 2471. 

 Ostracodermi, 260. 

 Ostrich, 4572. 

 Otaria, 626i. 

 Otidiphaps, 469^. 

 OtLs 4662. 

 Otocoelus, 400'. 

 Otocryptis, 3502. 

 Otocyon, 622i. 

 Otogype, 4632. 

 Otolemur, 652'. 

 Otolithus, 2352. 

 Otomys, 6332. 

 Otonycteris, 6472. 

 Otophidium, 2442. 

 Otrynter, 23Si. 

 Otter, 6241. 

 Ouacaria, 6571. 

 Oudenodon 4012. 

 Oulachan, 2162. 

 Ounce, 6I91. 

 Ourebia, 5902. 

 Ova, Mammalia, 518. 

 Ovary, Mammalia, 515. 

 Ovibos, 5912. 

 Oviduct, 87 ; Dipnoi, 



256. 

 Oviposition, Amphibia, 

 296 ; Amphioxus, 30. 

 Ovis, 5912. 

 Ovulation, Mammalia, 



517. 

 Ovum, Mammalia, 480 ; 



Vertebrata, 50. 

 Owl, barn, 4712 ; fgm. 



