596 



INDEX 



Myosepta, 466 

 Myotomes, 466 

 Alvrianida, 275, 277 

 Myriapoda, 402, 433 

 Myriotrochus, 308 

 Myrmecophaga, 563 

 Myrmicida-, 426 

 Myrmecocystus, 427 

 Mysilla, 205 

 Mysis, 376 



stage, 380 

 Mystaceti, 572 

 Mytilidae, 323 

 Myxicola, 277 

 Myxine, 493 

 Myxobolus, 190 

 Myxomycetes, 180 

 Myxospongia, 205 

 Myxosporida, 190 

 Myzobdella, 279 

 Myzontes, 493 



Nagana disease, 43 1 



Nageli's principle of pro- 

 gression, 48 



Naididre, 279 



Nails, 450, 545 



Nais, 271 



Naja, 531 



Nanomia, 219 



Narcomedusa?, 218 



Naris, 475 



Nanval, 572 



Nasal bones, 459 

 capsule, 457 



Natatores, 543 



Naticida;, 334 



Natural selection, 35 



Nauplius, 28, 362 

 eye, 362 



Nausithoe, 224 



Nautilus, 346 



Ncbalia, 375 



Nectocalyces, 218 



Nt-ctonema, 268 



Ncctonemertes, 2 58 



Necturus, 520 



Needham's sac, 344 



Nematocyst, 207 



Ncmatoda, 263 



Nemathelminthes, 263 



Nematus, 425 



Nemerteans, 255 



Nemertini, 255 



Nernocera, 430 



Nemopsis, 217 

 Neocranium, 455 

 Neocrinoida, 302 

 Nejgam, 162 

 Neo-Lamarckism, 47 

 Neomenia, 316 

 Neosporida, 190 

 Neoteny, 150 

 Nephelis, 284 

 Nephridia, 105, 272 

 Ncphridial tubules, 486 

 Nephrostome, 105, 242, 4^6 

 Nepidse, 428 

 Neptunus, 382 

 Nereis, 276 

 Neverita, 334 

 Nerve-cord, ventral, 113 

 Nerve-end buds, 474 

 Nerve fibres, 85 



hillocks, 474 

 Nerves cranial, 471 



eye-muscle, 472 



spinal, 468 



sympathetic, 473 

 Nervous system, in 



development of, 30 



of vertebrates, 467 

 Nervous tissue, 83 

 Neural arch, 453 



spine, 453 

 Neurapophysis, 4^3 

 Neurenteric canal, 439, 467 

 Neurites, 84 

 Neuroblasts, 86 

 Neuroglia, 114 

 Neuromasts, 474 

 Neurone, 86 

 Neuropodium, 276 

 Neuropore, 440, 468 

 Neuroptera, 421 

 Nettle bodies, 192 



cells, 207, 241 



Nictitating membrane, 477 

 Nidamental gland, 344 

 Night-hawks, 544 

 Nirmus, 420 

 Noctiluca, 184 

 Noctuina, 433 

 Nomarthra, 563 

 Nosema, 191 

 Nothria, 277 

 Notochord, 438, 452 

 Notochordal sheath, 452 

 Notodelphidas, 369 

 Notogffia, 162 



Notonectidse, 428' 

 Notopodium, 276 

 Notum, 404 

 Nuclear fragmentation, 62 



spindle, 60 



substance, 56 

 Nuclein, 56 



Nucleoli, chromatic, 57 

 Nucleolus, 57 

 Nucleus, 55 



cleavage, 135 



function of, 58 

 Nucula, 323 

 Nuda, 235 

 Nudibranchia, 335 

 Nummulites, 180 

 Nurse, 131 

 Nutrition, 55 

 Nyctotherus, 196 

 Nymphon, 399 



Obelia, 218 



Obisium, 394 



Obturator foramen, 522, 



55 

 Occipital bone, 458 



condyles, 514 

 Occipitalia, 458 

 Occiput, 405 

 Ocellatae, 216 

 Ocellus, 354 

 Ocneria, 433 

 Octocoralla, 230 

 Octopoda, 347 

 Octopus, 336, 347 

 Ocular plate, 297, 304 

 Oculina, 231 

 Oculomotor nerve, 471 

 Odonata, 420 

 Odontoholca?, 541 

 Odontophore, 329 

 Odontormse, 541 

 Odontornithes, 541 

 CEcanthus, 421 

 (Ecology, 50 

 CKdipoda, 421 

 Q-Mogonium, 160 

 (Knothera, 44 



Qvsophageal nerve ring, 113 

 (Esophagus, 94 

 Oigopsida, 347 

 Oikopleura, 443, 444 

 Oil bottles, 424 

 Okapia, 569 

 Olecranon, 465 



