Index 



505 



Skein, see Mitosis 



Skull, see Birds, Cyclostomes, 



Head, Vertebrates 

 Skunk, 435; distribution, 17G 



fur, 425 



warning color, ill. 339 

 Sloth, see Giant, Ground 

 Slye, 472 

 Smallpox, inoculation, 442, 447 



Indians, 441 



Philippines, 441 



Phila., 442 



Boston, 441-2 



N. D., 442-3 



see Immunity, Vaccination 

 Smilodon, distribution, 145 



extinction, 146 



prey, 146-7 



remains, 148 



structure, 145-6 

 Smith, A. C, 450 

 Smith, L. H., 238 

 Smithsonian Institution, estab- 

 lished, 60 

 Snake venom, see Immunity 

 Snail, organ-forming substances, 

 191 



fossil, 124 



regeneration, 193 



see Hawaiian, Tahiti, Cerion 

 Snow-bunting, distribution, 168 

 Snowshoe rabbit, distribution, 174 



ill. 173 

 Social Hygiene Board, see U. S. 

 Society, see American Naturalists 



and Geologists 

 Societies, see Plants 

 Solenhofen quarries, 131 

 Sonoran zone, 176, 178 

 Sounding apparatus, 363-5 

 Sparrows, weed destruction, 392 



tree, 392 



see English, Tree 

 Spawning, see Salmon 

 Species, defined, 327 



and geographic races, 248 



elementary, see Mutation 

 Sperm, union with egg, 327-8 



see Reproduction, Spermatists 

 Spermatists, 189 

 Sphaerechinus, giant larva;, 192 

 Spiders, fossil, 124 

 Spinal cord, see Vertebrates, struc- 

 ture 

 Spiracle, see Fish 

 Spirifer, constancy, 95 

 Sponges, Statoblasts, 382 



see Motility 



Spores, function, see Reproduction 

 Sporophyto, see Reproduction 

 Sporozoa, 93 

 Sports, see Mutation 

 Spruce, distribution, 172 



see Douglas 

 Squid, see Octopus 

 Squirrel, transport, 155 



see Ground 

 St. Hilaire, 235, 239 

 Stag, see Sexual selection 

 Stamen, see Flowers, reproduction 

 Starch, synthesis, 81, 297 



digestion, 279 



storage in plants, 299 

 Starfish, regeneration, 193 



see Cross fertilization, Inter- 

 crossing 

 State Board of Health, see Massa- 

 chusetts 

 Stations, see Biological 

 Statoblasts, see Sponges, Bryozoa 

 Stegocephala, 121; larvae, 124; 

 ill. 123 



structure, 123-4 

 Stegomyia, 188; see Mosquitoes 

 Stegosaurus, brain, 113, 127 



ill. 128 

 Steller, 426, 431 

 Stentor, structure, 306 



reactions, 306-11 

 Stereoisomers, 207-8 

 Stereotropism, ants, 316-7 

 Sterilization laws, 275-6 

 Sternberg, 451 



Sternum, see Birds, Pterodactyls 

 Stigma, see Flowers, reproduction 

 Stiles, 466-7 



Stockard, 194, 227, 251-2 

 Stomach, ferment, 295 

 Stone, 88 

 Stout, 233 

 Streeter, 84 

 Struggle for existence, 90, 281, 



353 

 Strychnin, see Crustacea, light re- 

 sponse 

 Stump Lake, N. D., 79 

 Styles, see Flowers, reproduction 

 Stylonichia, see Morgan 

 Sub-neural gland, see Tunicates, 



structure 

 Sugar, 81, 299 



cane, see Weevil 



conduction in plants, 299, ' 



formed from starch, 279 



metabolism, see Pancreas 



synthesis, 81, 297 



