Index 



495 



Human, machine, economy, 285 

 use of fuel, 294 



nutrition, 285 et seq. 

 Hume, 235 



Humming-birds, distribution, 185 

 Humboldt, 38, 450 



Valley, see Mouse plague 

 Huntington, 77, 79, 81; hospital, 



472 



Huronian period, life, 117 

 Huxley, 40 

 Hyatt, 69 



Hybrid infertility, 252 

 Hybridization, see Cotton, Muta- 

 tion, Orange 

 Hydatina senta, 232 

 Hydra, 92; grafting, 194-5 



regeneration, 192-3 



reproduction, control, 233, 327 



structure, 103 

 Hydrolysis of food, 295 

 Hydromedusse, indeterminate devel- 

 opment, 192 



Hygiene, see Industrial, Social 

 Hyoid, see Vertebrates, structure 

 Hypophysis, see Vertebrates 



Ice age, 143 

 Ichneumon, see Mongoose 

 Ichthyornis, 40, 131 

 Identical twins, 228 

 Illinois River, plankton, 383 

 Illinois State Laboratory of Nat- 

 ural History, 377 

 Images, see Memory 

 Immorality, sex, 270-2 

 Immunity, practices, theories, 447- 



448 



Imperial elephant, 148 

 Impulse, see Nervous 

 Inbreeding, see Eat 

 Incas, marriage customs, 85 

 Indian Plague Commission, 458 

 Indiana, see Sterilization 

 Industrial Hygiene, 476-7 

 Infertility, see Hybrid 

 Influenza, experiments, 476 



work of U. S. Public Health 



Service, 475-6 



Inheritance, 478; acquired char- 

 acters, 244-5 



Andalusian fowl, 259-60; ill. 259 



beans, pure lines, 236-7 



blending, 258-64 



cattle, color, 260; horns, 267-8; 

 ill. 267 



Inheritance, corn, 261-3 

 Drosophila, 260-1 

 four o'clock, 258-9; ill. 258 

 guinea pigs, 261, 263, 267; ill. 



261-2 



kinds, 257 

 man, color, 264-5 



examples, 270, et seq. 

 Mendelian, 203, et seq. 257 et 



seq., 479 

 Metaphyta, 257 

 Metazoa, 257 

 oats, 263 



peas, 203-5, 263; ill. 205 

 Protista, 257 

 rabbits, 265-6; lop-eared, 261. 



263; ill. 260 

 ratios, expected and realized, 



264-6 



segregation, 261, 264 

 shepherd 's purse, 265 

 see Chromosomes, Selection 

 Inland waters, see Biology 

 Inoculation, see Smallpox 

 Insectivores, 138 

 Insects, fossil, 124 



larvjB, oxygen requirements, 380 

 reactions, 312, et seq. 

 relation to flowers, 330-2 

 sex determination, 209, 230-1 

 see Hawks, Instinct, Isolation, 

 Mimicry, Scale, Sexual Se- 

 lection 



Instincts, ants, 316 

 birds, 319-20 

 fish, 314 

 insects, 319 

 mammals, 319 

 pigeons, sexual, 314-5 

 see Ammophila 

 Institute, see Carnegie, Phipps, 



Rockefeller, Wistar 

 Institution, see Bussey, Scripps, 



Smithsonian 



Intercrossing, salamander and 

 frog, sea urchin and star- 

 fish, 253 



Internal secretions, 320, 361; see 

 Glands, Salmon, life history 

 Internal perfecting principle, 234 

 International Council for Inves- 

 tigation of the Sea, 349, 

 360, 482 

 Intestine, see Absorption, Diges- 



,tion 

 Introduction, animals and plants, 



410 et seq. 

 Invertebrates, ancestral, 104 



