712 



INDEX 



Muscle (Cont.) : 



smooth, 85, 346, 504 



striated, 346 



voluntary, 346 

 Muscular system, 87 



bird, 438 



cat, 467 



clam, 283 



crayfish, 202, 211 



earthworm, 174 



fish, 381 



frog, 346-350 



Hydra, 107 



insect, 235 



lamprey, 361 



man, 505-507 



planaria, 136 



vertebrate, 83 

 Muscularis mucosae, 518 

 Musculocutaneous vein, 337, 338 

 Musk glands, turtle, 411, 429 

 Muskellunge, 394 

 Muskrat, 493 

 Mussels, frontispiece, 298, 299, 



301 

 Mustelids, 486 

 Mutations, 593, 621, 622 



Ancon sheep, 621, 622 



artificial, 593 



chemical genetics, 594 



Drosophila, 623 



radiogenetics, 594 



theory, 657 

 Mutualism, 636, 638 

 Mya, 298, 299, 301 

 Mycetozoa, 41 

 Mylohoid, 347, 348 

 Mylohyoideus, 467 

 Myocyte, 97 

 Myoneme, 504 

 Myopia, 596 

 Myotis, 495 



Myotome, 316, 318, 319, 381 

 Myrmecophaga, 482 

 Mysticeti, 496 

 Mytilus, frontispiece, 298, 299, 



301 

 Myxedema, 552 

 Myxidium, 53 

 Myxine, 367 

 Myxinoidea, 360, 366 

 Myxosporidia, 53, 75 

 Myzostomidae, 189 

 parasites, 189 

 protandric, 189 



N 



Nacreous layer, 283, 284 

 Nacre-secreting cells, 284 

 Nagana, 74 

 Naiad, 241 



Nail, 474 

 plate, 474 



Nd/a, 423 

 Nares, 333, 534 

 Narrowmouthed toad, 397 

 Narwhal, 486 



Nasal bones, 343, 344, 437, 500, 

 502 



cavity, 333 



sac, 351 

 Natrix, 417 

 Natural death, 563 



selection, 609, 649 

 Nautilus, 302 

 Neanderthal man, 626 

 Neanthes, 170, 183, 194, 196 

 Nearctic realm, 650 

 Nearsightedness, 596 

 NecatoT, 155, 157,161 

 Neck, 500 

 Necrophorus, 248 

 Necfurus, 402, 403, 404 

 Negative reaction, of Amoeba, 38 

 Nekton, 646 

 Nemathelminthes, 3, 149, 160 



classification, 161 



free-living, 153, 155 



origin and relations. 160 



parasitic, 151, 152, 154, 155 

 Nematocysts, 106, 107, 109, 110 

 Nematoda, 161 

 Nematodes, 3 



beneficial, 1 59 



parasitic plant, 154 

 Nematomorpha, 149, 160 



classification, 161, 162 

 Nemertina, 163 

 Neoceratodida, 394 

 Neoceratodontidae, 579 

 Neoceratodus, 392 

 Neomenia, 300 

 Neopilina galatheae, 282, 289, 



291, 298, 300 

 Neornithes, 456 

 Neoteny, 561 

 Neotropical realm, 650 

 Nephridiopore, 172, 173, 174, 



178 

 Nephridium, 168, 172, 174, 178, 



184, 185, 190, 224 

 Nephrostome, 172, 174, 178, 339 

 Neritic zone, 652 

 Nerve cell, 107, 108 



conducting, 108 



cord, 135, 136, 176, 318, 319, 

 352 

 central, 315 



dorsal root, 319 



inferolateral, 209 



lateral, 209 



motor, 108, 352 



net, 106 



optic, 209 



Nerve (Cont.) : 



process, 108, 1 17 



ring, 109, 120 



sensory, 108, 109, 552 

 Nervous coordination, 544 

 Nervous system, 87 



amphioxus, 520 



Arthropoda, 197 



bird, 438 



cat, 471 



central, 350, 545 



clam, 287 



crayfish, 202, 208 



dogfish shark, 572 



earthworm, 178 



fish, 584 



frog, 550-554 



Hydra, 108 



insect, 257, 238 



lamprey, 362 



liver fluke, 1 59 



man, 546 



Metazoa, 83, 87 



peripheral, 178, 550, 552 



planaria, 135, 156, 159 



spider, 271 



starfish, 506 



turtle, 411 

 Nervous tissue, 85, 86, 151 

 Nervus terminalis, 552 

 Nests, birds, 448, 449 

 Neural arch, 545 



canal, 502 



fold, 556, 557, 565 



groove, 556, 557 



plate, 565 



spine, 545. 502 



tube, 521, 565 

 Neurilemma, 353 

 Neurohormones, 555 

 Neurohumoral reflex. 544 

 Neurohumors, 555 

 Neuromotor apparatus, 543 

 Neuron, 352, 353, 544 



-effector system, 544 

 Neuropodium, 184 

 Neuroptera, 229,255, 260, 263 

 Neurospora, 594 

 Ncurula, 566 

 Neutrophil, 335, 526 

 Newt, 397, 404 



crimson-spotted, 401 



eastern, 401 

 New- World lizard, 430 

 Niacin, 523 

 Niche, 635 

 Nictitating membrane, 555, 452, 



465 

 Night blindness, 521 



hawks, 446,461,462 



monkey, 489 

 Nine-lxanded armadillo, 464, 479, 

 482 



