9S8 



INDEX 



Nervous system of cockroach, 374. 



^ of Coelentera, 173. 



-of crab, 338. 



of crayfish, 325, 325. 



of Crinoid, 312. 



of Crustacea, 355. 



of Distomum, 216. 



of dogfish, 613. 



of earthworm, 248. 



of frog, 659, 660. 



of haddock, 622. 



of Helix, 439. 



of Hirudo, 273. 



— — of Holothurian, 306. 



of Hydra, 176. 



of Insects, 388. 



of Lizards, 698. 



— - — of Lung-fish, 647. 



of Myxine, 576. 



of Nematoda, 237. 



-of Nemerteans, 231. 



-of Peripatus, 363. 



— ■ — of Petromyzon, 581. 



of pigeon, 744. 



of rabbit, 797. 



of scorpion, 414. 



of sea-urchin, 303. 



— — of Sepia, 459. 



of skate, 597. 



of spider, 419. 



of starfish, 293. 



of Vertebrates, 539. 



Nervures, 387. 

 Nesodon, 860. 



Nests of Birds, 760. 



Neurenteric canal, 526, 544. 



Neurilemma, 50. 



Neuroblast, 256. 



Neuro-muscular cells, 49, 176. 



Neurones, 50. 



Neuropodium, 266. 



Neuroptera, 406. 



Newt, section through young, 557. 



Newts, 649, 677. 



Nictitating membrane of eye, 552, 747, 784" 



Nine-eyes, 581, 582. 



Noctiluca, 134, 895. 



— spore-fonnation in, 143. 



— structure of, 141. 

 Nomarthra, 843, 845. 

 Nose, the, 547. 



— of Myxine, 577- 

 Nothosaurus, 720. 

 Notidanidae, 634. 

 Notochord, 7, 8, 45- 



— in embryo vertebrate, 537. 



— of Balanoglossus, 490, 491, 496. 

 Notommata, 282. 

 Notopodium, 266. 

 Notoryctes, 840. 

 Notoryctidae, 840. 

 Nototrema, 682. 



Nuchal organs, 259. 

 Nuclear spindle, 56. 

 Nucleolus, 54. 

 Nucleus, 53. 



Nucleus, division of, 55, 56. 



— pulposus, 787. 

 Nucula, 468, 480. 



Nudibranch, showing adaptive gills, 468. 



Nudibranchs, 474. 



Nummulites, 13, 132. 



Nutrition of marine annuals, 159. 



— of Protozoa, 137. 

 Nymph, 399. 

 Nymphon, 432, 432. 



Obelia, 204. 



— geniculata, 182. 

 Obstetric toad, 677, 682. 

 Obturator foramen, 795. 

 Ocellatae, 183. 



Ocelli, 389. 



Octacnemus, 511, 514. 



Octocoralla, 195, 205. 



Octopoda, 486. 



Octopus, 8, 455, 458, 482, 486, 488. 



Oculomotor nerve, 545. 



Odonata, 384, 407. 



Odontoceti, 862, 864. 



Odontoid process, 787. 



Odontolcae, 772. 



Odontophora [see Glossophora), 470. 



Odontophore, 434. 



Odontopteryx, 772. 



Oisophagus of Vertebrates, 556. 



Oigopsida, 485, 486. 



Oikopleura, 513. 



Okapi, 852. 



Olfractory lobes, 539. 



— nerves, 545. 

 Oligochaeta, 245, 264. 

 OUulanus, 240. 

 Omentum, 752. 

 Ommastrephes, 486. 

 Ommatidium of a compound eye, 327. 

 Oniscus, 350, 351. 



Ontogeny, 87. 

 Onychophora, 361. 



— general characters of, 361. 

 Oocyst, 127. 



Oogenesis and spermatogenesis, diagram 



of, 71. 

 Ooperipatus, 366. 

 Ooze, Atlantic, 133. 

 Opalina, 140. 

 Opalinopsa, 139. 

 Operculum of Gasteropods, 438. 



— of Limulus, 427. 



— of scorpion, 414. 



— of Teleostei, 616. 

 Ophelia, 516. 

 Ophidia, 703. 

 Ophiocoma, 300. 

 Ophiophagus, 709. 

 Ophiophoiis, 298. 

 Ophiothrix. 299, 300- 

 Ophiura, 300. 



Ophiuroid, pluteus larva of, 290. 



— ventral surface of disc of, 299. 

 Ophiuroidea, 298, 315. 

 Ophrydium sessile, 150. 



