INDEX. 



691 



Ogmiiis, 3691. 

 Ogmodon, 370-. 

 Ogmorhinus, 627-. 

 Oil- bird. 472-'. 

 Oil 2land, biixk, 410. 

 Okapia, 590i. 

 Old-wife, 2301. 

 Olecranon, 492. 

 Olfactory lobes, 68. 

 Olfactory organ of Ani- 



phioxus, 18 ; of fishes, 



78. 

 Oligodon, 368'. 

 Oligopleuridae, 213. 

 Oligorus, 2351. 

 Oligosarcus, 217-. 

 Olistherops, 238i. 

 Olm, 3072. 



Onimatophoca, 627^. 

 Omomys, 653^. 

 Omosternura, 270. 

 Onchorhynchus, 2161. 

 Oneirodes, 246^. 

 Onychodactvlus, 273, 



3061. 

 Onychodectes, 6091. 

 Onychodontidae, 175. 

 Onychogale, 535-. 

 Onvclioinvs, 634i. 

 Onchus, 147, 262. 

 Opah, 2281. 

 Operculum, Amphibia, 



279, 280 ; Dipnoi, 



249. 

 Ophichthus, 225i. 

 Ophichthys, 2231.2251. 

 Ophiderpeton, 315i. 

 Ophidia, 355. 

 Ophidium, 2442. 

 Ophiocephalus, 201, 210, 



2321. 

 Ophiodes, 351 2. 

 Ophiodon, 2421. 

 Ophiognomon, 352^. 

 Ophiomonis, 3541. 

 Ophiops, 3532. 

 Ophiopsis, ISO. 

 Ophiopsiseps, 3542. 

 Ophioscion, 2352. 

 Ophisaurus, 3512. 

 Oj)hryoes.sa, 351'. 

 Ophrysia, 4652. 

 Ophthahnic canglion, 



135. 

 Ophthalmicus profun- 

 dus, 73, 135. 

 Ophthalmo saurus, 395i. 

 Opisthococlous, 161, 



317. 



Opisthocomus, 4661. 

 Opisthoglyiiha, 3682. 

 Opisthognathus, 2352. 

 Opisthomi, 245'. 

 Opisthoneina, 2142. 

 Opisthopterus, 2142. 

 Opisthotropis, 3671. 

 Opossum, 5391. 

 Opsanus, 244'. 

 Opsariichthys, 220i. 

 Optic chiasma, 69. 

 Optic lobes, 67. 

 Optic thalami, 69. 

 Optic vesicles, 68. 

 Or. = Oriental. 

 Oral cirri, 11, 19. 

 Oral hood, 19. 

 Orang-utan, 661 1. 

 Orca,"5632. 

 Orcella, 5632. 

 Orcynus, 2382. 

 Oreas, 5911. 

 Oreinomys, 6332. 

 Oreinus, 219i. 

 Oreobatrachus, 313'. 

 Oreodon, 579, 585i. 

 Oreonectes, 2211. 

 Oreophasis, 465i. 

 Oreophrynella, 3121. 

 Oreopithecus, 659 1. 

 Oreopsittacus, 4702. 

 Oreosaurus, 3522. 

 Oreosoma, 240i. 

 Oreotragus, 5902. 

 Orestias, 227 1. 

 Oi'iole, American, 478i, 



oolden, 4771. 

 Oriolus, 4771. 

 Ornithochirus, 3902. 

 Ornithodelphia, 525. 

 Ornithopoda, 386. 

 Ornithorhynchus, 490, 



494, 529, o:iG. 

 Ornitlioscelida, 383. 

 Ornithosuchus, 382i. 

 Orodus, 1511. 

 Orohippus, 5991. 

 Oronasal groove, 120. 

 Ortalis, 4(551. 

 Orthacodus, 1521. 

 Orthagoriscus, 92, 183, 



198. 195, 223,2472. 

 Orthodon, 220'. 

 Orthognathism, 489. 

 Orthopoda, 386. 

 Orthopristis, 236 1. 

 Orthostichous, 06. 

 Orthostomus, 241 1. 

 Orycteropus, 542, 5491. 



Oryx, 5911. 



Oryzomys, 634i. 



Oryzoryctes, 641 1. 



Os cloacae, 342. 



ds coccygis, 265. 



Os cines, 475. 



Os innominatum, 491. 



Osmerus, 208, 2161. 



Os penis, 515. 



Osphromenus, 2371. 



Os planum, 486. 



Osprey, 464i. 



Osseous tissue of Elas- 

 mobranchii, 122. 



Ostariophysi, 2162. 



Osteobraiiia, 2202. 



Osteochilus, 2192. 



Osteoderms, 317, liz- 

 ards, 337. 



Osteogeniosus, 2212. 



Osteoglossum, 215i. 



Osteolaemus, 3832. 



Osteolepis, 175. 



Osteostraci, 261. 



Ostracion, 246, 2471. 



Ostracodermi, 260. 



Ostrich, 4572. 



Otaria, 626i. 



Otidiphaps, 4691. 



Otis, 4662. 



Otocoelus, 400'. 



Otocrvptis, 3502. 



Otocyon, 822i. 



Otogvps, 4632. 



Otofemur, 652 1. 



Otolithus, 2352. 



Otomys, 6332. 



Otonyctei-is, 6472. 



Otophidium, 2442. 



Otrynter, 236i. 



Otter, 6241. 



Ouacaria, 657i. 



Oudenodon., 4012. 



Oulachan, 2162. 



Ounce, 6I91. 



Ourebia, 5902. 



Ova, Mammalia, 518. 



Ovarv, 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, 47 P ; fern, 



