Fucus, 75 



Function, def., 130 



Fungi, 73, 90, 375; bracket, 75; and disease, 311; 



and nitrogen cycle, 377-378; as plant parasites, 



386-387 

 Funk, Casimir, "vitamine," 177 

 Fused nucleus, definition, 441 



Gall (bile). 192 



Gall bladder, of man, 189, 192, 195 

 Game laws, 406 



Gametes, active (supplying), 416; and chromosomes, 

 466-467, 466 ; conjugation of, 415-418 ; of dihybrid, 

 472; eggs, 423; def., 415; 415-418, 422-423. 

 429-430, 432; fertilization of, 423-424: fish, 427; 

 formation, 460^461; frog, 427-428; and germ 

 plasm, 455; an<l heredity, 466-473, 466, 467, 469, 

 471, 472, 473; like, 417; mammalian, 432; matura- 

 tion, 460-461. 461; passive (receiving), 416; plant, 

 439, 441, 441, 442, 442, 446-447; pure, 466; sperm, 

 423; spirogyra, 416; unlike, 417-418 

 Ganglia, 275; autonomic, 275, 279, 279; bee, 275; 



earthworm, 57; in reflex arc, 277-279, 278 

 Garden spider, 51 

 Garter snake, 26 



Gastric glands, 191, 191, 195, 199, 200; duct of, 191 

 Gastric juice, 193-194 

 Gastrula, def., 425; 425, 426 



Gene, def., 456; action of, 459; and breeding, 49.3- 

 507; changes in, 479-481; and chromosome, 457; 

 effect of environment on, 490-491; and four 

 o'clock heredity, 466-467: and grafting, 503; and 

 heredity, 456-484; and light, 490; revisions in 

 theory, 483; theory, 456 

 Genus (genera, pi.), 15, 97, 98, 98, 99, 100, 101 

 Geographic distribution, of organisms, 551-552 

 Geologist, 521, 525 



Geometrid moth caterpillar, and adaptation, 560 

 Geotropism, 301 ; in sunflower, 302 

 Geranium, 72, 131 



Geranium, oil, and Japanese beetle, 396 

 Germ cells, def., 455 (see Gametes) 

 Germ layers, in animal development, 426 

 Germ plasm, 455; and acquired characters, 488, 489; 



continuity of, 455, 488, 489 

 Germ theory of disease, 320-322. 323, 332; advances 



in, 338-342; and Koch's postulates, 322 

 Germination, def.. 438 

 Germs, def., 311; and disease, 311-371; spread of, 



347-349 

 Gestation, def., 433 

 Giantism, 253 

 Gila monster, 29 

 Gill slits, in embryos, 548 

 Gills, fish, 32 

 Giraffe, 559 



Gizzard, of earthworm, 57 

 Glacial period, 539-540 

 Glacier, def., 522; 522; and ice sheet, 540 

 Gland, def., 191; cells, 129; tissues, 131 

 Glands, "of Combat," 252-253; gastric, 191, 191, 

 195, 199, 200; of internal secretion (endocrine), 

 246-258; intestinal, 196; oil. 240; salivary, 189, 

 192, 199; sweat, 239-240, 240 

 Glasses, to correct vision. 281 

 Glowworm, 46 

 Glucose, 190, 196, 199 

 Glycerin, 196, 198 

 Glycogen, 199; and insulin, 250 

 Gneiss, 524 

 Goats, and overgrazing, 403 



Gobi Desert, 526; and fossils, 528-530 



Goblet cells, 195, 227 



Goiter, 249 ; exophthalmic, 249-250; map of distribu- 

 tion, 249; treatment of, 248 



Goldfish, 32 



Gonorrhea, 333 



Gooseberry, and blister rust, 386 



Gooseflesh, 253 



Goose pimples, 241 



Gopher, 97 



Gorgas, W. C., and mosquito extermination, 353 



Grafting, def., 502 ; 503; and plant breeding, 502-503. 



Grains, 84-85 



Grand Canyon, 529; and fossils, 528 



Granite, 521, 524 



Granules, 111 



Graph, of bean length, 487; def., 487; of intelligence 

 quotients, 511 



Grass, extinction of blue stem, 405 



Grasses, 83, 84, 85 



Grasshopper, 40, 45-46, 45; mouth parts, 68 



Gravity, and plant hormones, 303-304; and tro- 

 pisms, 301 



Gray matter, of brain, 272; of spinal cord, 272 



Great auk, extinction of, 405 



Greenland, ice cap, 540 



Green plants, and food chains, 373 



Gristle (see Cartilage) 



Grizzly bear, California, extinction of, 405 



Ground pines, 80 



Ground sloth. 528 



Grouse, hatching, 431; protective adaptation, 560 



Growing point, of root, 152 



Growing up, and emotions, 297-298 



Growth, and plant behavior, 303-304 



Growth hormones, synthetic, 308 



Guano, def., 405; use of, 405 



Guard cells, 139, 139 



Guinea pig, 176; and acquired characters, 490; 

 heredity of, 467, 470 



Gull. 431 



Gullet, 193; of Paramecium, 62 (see Oesophagus) 



Gustafson. Dr. F. G., and plant reproduction, 450 



Gymnosperms, def.. 81; 81-82. 91 



Gypsy moth, caterpillar, 392; 393 



Habits, 292-294; breaking (unlearning), 294; com- 

 pared with reflexes, 292-293; formation of, 294; 

 safely, 363 



Hair, follicle, 240; heredity in cats, 465; of man. 

 240; roots, 241 



Halibut liver oil, and vitamin D, 181 



Hammer, bone of ear, 282 



Haploid, def., 460; effect on organism, 481-482; in 

 maturation of gametes, 460-461, 461 



Hardwoods, 85 



Harrison, Dr. Ross, and tissue culture, 340 



Harvey, William, and blood circulation, 214 



Hatchet foot mollusks, 53, 54, 55 



Hawaii, 525 



Hay fever, 364-365 



Hay infusion, 61-63 



Head louse, 390 



Health, 311-371 ; and education, 369-370; laws, 344, 

 348; mental, 367-368; and poverty, 370; and 

 social problems, 370; workers of Board of, 323, 

 329, 374 



Health ofliccrs, and disease carriers, 347-348; ami 

 disease p)revention, 343-344 



Heart, 121, 207; beat, 214; counting beat, 215; 

 disease, 361-362; earthworm, 57; in human em- 



606 



