INDEX 



721 



Nails, 677. 



Niiis, 236. 



Naja, 539, 565. 



Narcomedusa', 128. 



Nares, 481, 482, 483. 



Narwhale, 674, 675. 



Nasals, 493, 4Q4; aperture, 415. 



Natalities, 651. 



Natantia, 297, 299. 



Natrix, 561. 



Nauplius, 289, 303, 304. 



Nautilus, 268, 269. 



Neanderthal man, 696. 



Nebalia, 294, 295 ; Nebaliacea, 294, 295. 



Necator, 175. 



Nectonema, 179. 



Nectophore, 125, 126. 



Necturus, 161, 511, 513. 



Nemathelminthes, 24, 25, 169-175. 



Nematocera, 356. 



Nematocysts, 109, in, 112, 131, 134. 



Nematomorpha, 179. 



Ncmatus, 365. 



Nemer tinea, 177, 178, 179. 



Neoceratodus, 446, 471. 



Neornithes, 575, 594. 



Neosporidia, 52. 



Nephridia, 216, 223 (see excretory sys- 

 tem). 



Nephridiopore, 216, 217 (see excretory 

 system) . 



Nephrocytes, 196. 



Nephrostome, 216, 223, 491. 



Nereis, 232, 233, 234-235. 



Nerves, cranial, 408, 409; spinal, 408. 



Nervous system, 79; central, 224, 408; 

 peripheral, 224, 408; sympathetic, 

 408, 410. 



Nervous system of, Amphioxus, 397, 

 399; Ascaris, 170; crayfish, 278, 284; 

 dogfish, 427; earthworm, 223, 224, 

 225, 226; Enteropmusta, 387, 388; 

 frog, 501-504; Gonionemus, 123; 

 honey-bee, 318, 320; Hydra, 112; 

 lamprey, 418; liver fluke, 157 ; mussel, 

 247, 249; nemertine, 177, 178; perch, 

 440 ; Peripatus, 307, 308 ; pigeon, 

 587; Planaria, 152, 153; rabbit, 639; 

 snail, 256; spider, 373, 375; squid, 

 267 ; starfish, 195, 197 ; tapeworm, 

 164; tunicate, 391 ; turtle, 533; ver- 

 tebrates, 407, 408, 410. 



Nervous tissue, 75, 76. 



Nervurcs, 333. 



Nests, of birds, 624-625. 



Neural, arch, 402, 404, 493, 495 ; spine, 



404. 



Neuroccele, 386. 

 Neuron, 225. 

 Neuroptera, 337, 349. 

 Newt, 515. 



Nictitating membrane, 413, 505, 576. 

 Night-hawk, 612. 

 Noctilionidce, 651. 

 Noctiluca, 48. 



Noclua, 332; Noctuidir, 354. 

 Noddie, 608. 

 Nose, 410. 

 Nosema, 52. 

 Nostril, 478. 

 Notacanlhiformes, 444. 

 Notochord, 386; of Amphioxus, 396, 



397; Knteropneitsta, 387; dogfish, 



424; lamprey, 416, 417; perch, 435; 



tunicate, 390, 392; vertebrates, 401. 

 Notonedida, 348. 

 Notoryctida, 649. 

 Nototrema, 512, 520. 

 Nonius, 347, 363. 

 Nucleolus, 13. 



Nucleus, 12, 13, 14, 15, 16, 17. 

 Niicula, 262. 

 Nudibranchs, 260. 

 N urn idea, 631. 

 Nuthatch, 591. 



Nutrition, 112 (see digestive system). 

 Nymph, 336, 338. 

 Nymphalida, 352. 



Obelia, 110-122. 



Obisium, 382. 



Ocapia, 671. 



Occipital condyles, 493, 494, 579, 635. 



Ocelli, 131, 312, 313. 



Octopoda, 268, 269 ; Octopus, 269. 



Oculina, 141, 142. 



Odobienidie, 657 ; Odobcenus, 643, 657. 



Odocoileus, 669. 



Odoiiata, 337, 339. 



Odontoceti, 645, 674-675. 



(Ecodoma, 369. 



(Esophagus. 480 (see digestive system). 



(Estrida, 359. 



Oiko pleura, 393. 



