INDEX 



429 



Molds, 312, 313 



Molecules, 43, 44, 45, 46 



Mollusca, 173, 330; classified, 269, 273 



MoUuscan type, 18 



MoUusks, 187; classified, 273; parts fos- 

 silized, 311 



Melothrus ater, 17 



Monaxonida, classified, 269 



Mondino da Luzzi, 10, 11 



Monkeys, 335 



Monocystis, 172, 177 



Monodelphia, classified, 271 



Monoecious, 184 



Monogenea, classified, 269 



Monotremata, classified, 271 



Morgan, T. H., 344 



Morphology, 1, 2, 6; of the cell, 25-42; of 

 higher types, 105-142; in taxonomy, 

 268 



Moss animals, 171 



Motion, voluntary, 162, 163 



Motor neurons, 160, 161 



Motor root of spinal nerve, 230 



Mouse, northern jumping, range of, 292 



Mouth, 116, 117, 120, 226, 228; diges- 

 tion in, 143, 144; of earthworm, 119 



Mouth cavity, 117 



Movement, amoeboid, 60, 61, 62, 73; of 

 chromosomes, explanation of, 73; 

 ciliary, 60, 62, 63; involuntary, 163; 

 protoplasmic, 60 



Mucin, 110; in salivary secretion, 144, 153 



Mucosa, 95; in duodenum, 145; gastric, 

 144; in small intestine, 146 



Mucus, 110; in saliva, 144; secretion of, 

 153 



Mud, origin of animals from, 165 



Muellerian duct, 132 



Miiller, Johannes, 263 



Musca, egg of, 125 



Muscicapa, sperm of, 216 



Muscle, 112, 120, 133, 136, 156; in ar- 

 teries, 156; circular, 133, 156; con- 

 traction of, 156; control of, 162, 163; 

 cytoplasm of, 157; of digestive tract, 

 156; fibrilla; of, 156, 157, 158; in 

 gall bladder, 156; glycogen in, 158; 

 of the hair, 163; heart, 113, 156; in- 

 voluntary, 156; lactic acid formed in, 

 158; longitudinal, 133, 156; nerve 

 endings of, 163; nuclei of, 156, 157; 

 oxidation in, 158; of setse, in earth- 

 worm, figure of, 134; sheath, 157; 



smooth, 112, 156; striated, 112, 113 

 156, 157; structure of cells, 156; in 

 urinary bladder, 156; in veins, 156; 

 of the viscera, 163; voluntary, 113, 

 156 



Muscle cells, 60 



Muscular contraction, 61; influenced by 

 secretions, 154, 155 



Muscular fibrils, 65 



Muscular system, of earthworm, 119 



Muscular tonus, infiuenced by secretions, 

 154 



Musk ox, range of, 289 



Mussels, egg carrying in, 199. (See also 

 Clams.) 



Mustelus mustelus (see Sharks). 



Mutability of species, 22 



Mutation, 257, 344, 346, 355, 357, 363; 

 chromosomes in, 355; direction of, 

 360; in Drosophila melanogaster, 345 

 in guinea-pigs, 347; mechanism of, 

 347; in mice, 347; in Oenothera, 345; 

 346, 347, 348; proteins in, 355 



Myoccele, 223 



Myonemes, 65, 155, 156 



Myotome, 115, 116, 210, 223 



Myriapoda, classified, 270, 273 



Mysidacea, classified, 270 



Mystacoceti, classified, 271 



Myxine, hermaphroditism in, 190 



Myxinoidea, classified, 270 



Myxomycetes (see Slime-molds). 



Myxosporidia, classified, 268 



Narcomedusse, classified, 269 



Nasal aperture, 120 



Nasal openings in elephant series, 320 



Natural selection, 22, 252, 341, 342, 343, 



359 

 Nature of fertilization, 187 

 Nature of fossils, 310 

 Nautiloid, 173, 330; suture of, 330 

 Nautilus, 330, 332 

 Neanderthal man, 336 

 Nebaliacea, classified, 270 

 Nebraska, 183 

 Nectocalyces, 99 

 Necturus, 122 

 Nemathelminthes, 116, 172; classified, 



269, 272 

 Nematocysts, 99 



Nematomorpha, classified, 270, 274 

 Nemertinea, classified, 270, 274 



