660 



INDEX 



Moose, 509 



Morchella, 73 



Morgan, 458, 461, 462, 468, 469, 502, 



503 

 Mosquitoes, 102, 216, 222 



Anopheles, £28 



Culex, 238 



mouth parts of, 487 

 Mosses, 73, 498, 506 

 Moths, 468 



Motion, the "Why" of, 334 

 Motorium, 343, 375 

 Mouse, 495, 499 



Mouth parts, homologous, 486, 487, 488 

 Movement, devices for, 334 

 Mucor, 71 

 Mucosa, 289 

 Mucous membrane, 284 

 Miiller, Johannes, 391 

 MultipHcation of cells, 415 

 Murex, 505 

 Musci, 73 

 Muscle cell, 341 

 Muscle bands, 339 



Muscles and muscular systems, 336-340 

 Muscles 



circular, 335, 337 



earthworm, 192-193 



exoskeletal, 336 



fusiform, 338 



heart, 336 



inner longitudinal, 335 



involuntary, 327, 336, 337 



longitudinal, 337 



origin of, 337, 338 



skeletal, 336, 337, 338 



smooth, 327, 336, 337 



striated, 336, 337, 339 



voluntary, 327 

 Muscular activity, 339 

 Muscular contractions, 339 

 Muscular relaxation, 339 

 Musculature, human, 337, 338 

 Mussels, 333 

 Mutations, 442, 524-525 

 Mutual aid, 48 

 Mycelium, mold, 173 

 Mycorhiza, 55 

 Myelencephalon, 346, 351 

 Myology, 327 

 Myriapoda, 99, 103, 315 

 Myriapods, 532 

 Mystacoceti, 117 

 Myxomycetes, 71 

 Myxosporidia, 77 



Naididae, 411 

 Nannoplankton, 22 

 Nasion, 663 



National Parks and Forests, 605 



Native behavior patterns, 377-378 



Natural potencies, 432 



Natural selection, 443, 518, 524 



Naudin, 442 



Navicula, structure of, 163 



Neanderthalers, 557, 560 



Necator americanus, 223 



Neck, 286 



Necturus, 109 



Needham, 406 



Negroes, 562 



Nekton, 22 



Nemalion, 71 



Nemathelminthes, 87, 103 



Nematocysts, 180 



Nematoda, 87 



Nemertinea, 85 



Neolithic division of Stone age, 547, 560 



Neornithes, 113 



Nephridia, earthworm, 192 



Nephroi, 488 



Nephrostome, 192, 320 



Nereis, 93 



Nerve cell, 340, 343 



Nerve cord, 233 



Nerve impulse, 339 



Nerve net, 343 



Hydra, 183 

 Nerve ring, 343 

 Nerves, peripheral, 340 

 Nervous system, 233 



bee, 211 



physiological unit, 341 



protective devices for, 343 



types of, 342, 376 



unit of structure, 340 

 Nest-building, a genetical adaptation, 



490 

 Netherlanders, 562 

 Neural groove, 420 

 Neurilemma, 340 

 Neuromotor apparatus, 335, 342 

 Neuron, 340 



definition of, 195 

 Neuroptera, 100 

 Nitella, 71 

 Nitrogen cycle, 60 

 Nitrogenous wastes, 319 

 Nodes, lymph, 304 

 Noguchi, 619 

 Nolan, 212 

 Non-chordates, 328 

 Non-disjunction, 456, 457 

 Nordic races, 561 

 Norman, J. R., 45 

 Nostoc, 69 

 Nostrils, 284, 317 

 Notochord, 69, 233, 329 



