534 



INDEX 



234; of Holocephali, 281, 282; of Lim- 



ulus, 173; of Pipa, 304; of Salmo, 291; 



of Teleostomi, 283. 

 Ophidia, 315, 426, 451. 

 Ophiodon elongates, 293. 

 Ophioglypka bullata, 95. 

 Ophiophagus, 318. 

 Ophiuroidea, 93. 

 Opisthobranchia, 237. 

 Opossums, 366, 438, 452-454. 

 Optic lobe, of frog, 301; of roach, 286; of 



trout, 288. 

 Oral hood, 268. 

 Orang-utang, 410, 436, 454; skeleton of 



hand, 377. 

 Orbulina, 27. 

 Ore a gladiator, 374. 

 Order, 9. 



Organ, definition of, 5. 

 Organism, definition of, 5. 

 Organ-pipe coral, 77. 

 Oriental region, 453. 

 Origin, of animals, geologically, 442; of 



instinct, 485; of Mammalia, 362; of 



man, 478; of species, 458; of Species, 



508 ; of variation, 469. 

 Orioles, 355. 

 Ornithodelphia, 362. 

 Ornithorhynchus paradoxus or anatinus, 



363. 454- 



Orohippus, 433. 



Orthoceras, 425. 



Orthoptera, 202, 226, 227, 424. 



Orycteropus cap ens is, 368. 



Oscaria, 56. 



Osculum, 54. 



Osprey, 346. 



Ostracoda, 152. 



Ostracodermi, 420, 423. 



Ostrea angulata, 246; 0. edulis, 246; O. 

 virginiana, 246. 



Ostrich, 338. 



Otic processes, of frog, 300. 



Otocyst, definition of, 65; of Cephalopoda 

 250; of Lamellibranchia, 246; of me- 

 dusae, 63, 65 ; of veliger, 233. 



Otters, 399. 



Ova, of Teleostei, 287. 



Ovary, of Balanus, 158; of birds, 335; of 

 Bugula, 130; of cockroach, [95; ol 

 Cyclops, 154; of Doliolum, 265; of Es- 

 theria, 151 ; of Hirudo, 144 ; of lamprey, 

 273; of Lepas, 157 ; of Mammalia, 361 ; 

 of Sagitta, 125; of sea urchin, 99; of 

 Sepia, 252 ; of Teleostei, 287 ; of Trichina, 

 123. 



Ovibos moschatus, 383. 



Oviduct, of Balanus, 158 ; of birds, 335; of 

 Cyclops, 154; of Lepas, 157; of Mam- 



malia, 361; of Selachii, 280; of Sepia, 



252 ; of Teleostei, 287. 

 Oviparous Mammalia, 361, 362. 

 Ovipositor, 203, 222. 

 Ovis aries, 384. 

 Ovists, 498. 

 Ovotestis, 229. 

 Ovulists, 498. 



Ovum, human, 52; of sea urchin, 52. 

 Owen, 507. 

 Owl parrots, 348. 

 Owls, 347, 348. 



Ox, 384 ; skeleton of fore foot, 377. 

 Oxen, 453. 



Oxeote spicules, of sponge, 55. 

 Oysters, 246, 247. 



Pachydermata, 380. 

 Pedogenesis, 196. 

 Pagurus bernhardus, 169. 

 Painted turtle, 324. 

 Painter, 404. 

 Palasarctic region, 452. 

 Pal canon, 168. 

 Pala-odictyoptera, 423. 



hatteria, 421. 

 Palaeontological evidence of evolution, 470. 

 Palaeontology, 7,417,514; definition 0^513. 



ozoic era, 13; duration of, 422, 443. 

 Palaeozoic vertebrates, 420, 421. 

 Pallets, of Teredo, 249. 



ial line, 243, 244. 

 Pallial sinus, 133, 243, 244. 

 Pancreas, of dogfish, 277 ; of frog, 301 ; of 



Mammalia, 360; of pigeon, 333. 

 Pancreatic ducts, of pigeon, 333. 

 Pangenesis, 477. 

 Pangolins, 369. 

 Panmixia, 467. . 



rpa communis, 211. 

 Panther, 403, 404. 

 Paradi ea, 555. 

 Paragastric cavity, 55. 

 Parakeets, 348. 

 Paramcecium caudatum, 46. 



pet, 158. 

 Parapodia, 135, 137. 

 Parasitic barnacles, 158, 159. 

 Parasitic bees, 225. 

 Parasitic vertebrate, 274. 

 Parasphenoid, of trout, 288. 

 Parietal eye, 308. 

 Parrots, 346, 347. 



henogenesis, definition of, 128; in in- 

 sects, 196. 

 Parthenope, 171. 

 Partridges, 349. 

 Passeres, 353. 

 Patagonian cavy, 390. 



