INDEX 



537 



Movement and locomotion, 168 

 Mulatto parents, 243 

 Miiller, Johannes, 35 

 Murex, 383 

 Muscle, striated, 121 



voluntary, 115 

 Muscles, action of, 115 

 Muscular system of frog, 88 



of vertebrate, 159 

 Mussel, fresh-water, 372 

 Mutation theory, 508 

 Mutations, 249, 508 

 Mutualism, 428 

 Mycetozoa, 271 

 Myelencephalon, 218 

 Myocomma, 154 

 Myofibrils, 121 

 Myology, 116 

 Myosepta, 154 

 Myotomes, 101, 154 

 Mvriapoda, 395 

 Mysis, 413, 414 

 Mystacial vibrissae, 108 

 Myxedema, 198 

 Myxidimn, 275 

 Myxobolus, 275 

 Myxosporidia, 275 



N 



Nagana, 281 



Nares, 122 



Natural selection, theory of, 507 



Nauplius, 413, 483 



Nautilus, 373 



Nearctic region, 473 



Necator, 438 



americana, 443 

 Negro, 243 



Nemathelminthes, 23, 335 

 Nematocysts, 23, 308, 315 

 Nematoda, 438 

 Nematodes, 443 

 Nemertina, 24, 324 

 Neocomatella, 361 

 Neotropical regions, 474 

 Nephridia, 23, 157, 189, 343, 351 

 Nephridiopore, 343, 346, 351 

 Nephrostome, 80, 343, 351 

 Nereis, 344 

 Nerves, cranial, 137 



peripheral, 137 

 Nervous conduction, 182 



functions, 180 



system, development, 218 

 of frog, 90 

 of rat, 132 

 of vertebrate, 163 

 Neural groove, 100, 216 



Neural — Cont'd 



plate, 218 



tube, 100, 218 

 Neurites, 137 

 Neurocoele, 92, 136, 154 

 Neuro-epithelial cells, 181 

 Neurone, 57, 133 

 Neurones, 181 

 Nicotinic acid, 175 

 Nicitating membrane, 66 

 Nipples, 109 

 Nitrogen cycle, 28 

 Noctiluca, 269 

 Nomenclature, 259 



binomial system, 35, 259 

 Notochord, 146, 154 



rudimentary, 149 

 Nuclear sap, 48, 49 

 Nucleus, 48 



discovery of, 40 



O 



Oak-deer biome, 464 



Obelia, 63, 299, 304, 305, 306 



Occipital condyle, 84 



Ocelli, 418 



Ochre starfish, 362 



Octopus, 23 



Oculina, 310 



Oculomotor nerve, 92, 137 



Oenothera, 508 



Oestrin, 205 



Oestrus cycle, 224 



Olecranon, 114 



Olfactory epithelium, 93 



organs, development, 219 

 Oligochaeta, 342 

 Ommantidium, 405, 406 

 Omphalomesenteric vein, 220 

 Onchocerca, 438 

 Oniscus, 411 

 Ontogeny, 21, 225, 414 

 Onychophora, 395, 483 

 Oocyst, 276 

 Oocyte, 210 

 Oogenesis, 209 

 Oogonia, 210 

 Ookinete, 276 

 Opalina, 272, 437 

 Operculum, 448 

 Ophioderma, 359 

 Ophiothrix, 359 

 Ophiura, 359 

 Ophiuroidea, 359 

 Optic chiasma, 90 



cup, 219 



lobes, 91 



stalk, 219 



vesicles, 219 



