INDEX 



423 



Funiculus, 100 

 Fusion, 190 



Galactase, 146, 



Galen, 10, 11 



Gallbladder, 118, 120, 145, 228; muscles 

 of, 156 



Gall-forming insects, 181, 281 



Galliformes, classified, 271 



Gal vano taxis, 285 



Galvanotropism, 285 



Gamboge, 46 



Gametes, 90, 174, 176 



Ganglion, 116, 139, 160, 161; dorsal root, 

 142, 229 



Ganglionic masses, 114 



Gar-pike, cleavage in, 219 



Garter-snakes (see Thamnophis) 



Gas, a glandular secretion, 154 



Gases, an environmental factor, 283 



Gasterosteus aculeatus, habitat of, 277 



Gastric glands, 144 



Gastric juice (see Secretion) 



Gastric mucosa, absorption through, 144 



Gastric secretion (see Secretion) 



Gastropoda, classified, 269, 273 



Gastrotheca monticola (see Marsupial 

 frog) 



Gastrovascular cavity, 115; of Hydra, 94 



Gastrula, 220 



Gastrulation, 220; in Amphioxus, 220; 

 in homolecithal embryos, 220; in 

 Synapta, 221; in telolecithal em- 

 bryos, 221 



Geese, origin of from barnacles, 165 



Gelatin, 32 



Gemmules, 169 



Genera, range of, 290, 291 



Genes, 78, 240, 257; nature of, 255 



Genetics, 22, 23, 27, 69, 239-259; evolu- 

 tion and, 257; practical applications 

 of, 258-259; race and, 258; scope of, 

 239 



Genital system, essentials of, 128; func- 

 tion of, 127-130; structure of, 127- 

 130 



Genital systems with accessories, 128 



Genus, defined, 262, 263, 264 



Geoffroy-Saint-Hilaire, 21 



Geographical changes and succession, 287 

 Geograpliical distribution, as evidence of 

 evolution, 351; in taxonomy, 267, 

 268. (See also Zoogeography.) 



Geography, of Cretaceous time, 353; of 

 Permian time, 352 ; of Tertiary time, 

 318 



Geological time scale, 315 



Geotaxis, 285 



Geotropism, 285 



Gephyrea, classified, 270, 274 



Germ cells, 116, 127, 174, 2C6, 209, 210, 

 236, 237, 238; early origin of, 206- 

 209; immortality of, 236; indepen- 

 dence of, 235-238; migration of, in 

 vertebrates, 210; mode of discharge, 

 128; a reserve supply, 236 



Germinal epithelium, 116, 210 



Germ layers, 223 



Giant salamander (see Crj^ptobranchus) 



Gibraltar, Neanderthal man discovered, 

 336 



Gill, 121, 235; an adaptation, 275; eggs 

 carried in, 200; excretion through, 

 150, 151; external, 233; internal, 233; 

 occurrence of, 121; in respiration, 

 148, 149 



Gill arches, 121, 122. (See also Gill bars.) 



Gill bars, 226, 227, 235, 350. (See also 

 Gill arches.) 



Gill clefts, 221, 226, 235. (See also Gill 

 shts.) 



Gill pouches, 226, 227, 235 



Gill slits, 121, 227. (See also Gill clefts.) 



Girdle, pectoral, 137; pelvic, 137 



Gizzard, 117; of earthworm, 119 



Glacial, in time scale, 315 



Glacial stage, fourth, 336 



Gland, 59, 110, 117; alveolar, 111; com- 

 pound alveolar. 111; compound tu- 

 bular, 111; defined, 112; effect of 

 secretions, 154, 155; examples of, 

 112; innervation of, 163; parts of, 

 111; products of, 154, 155; secretions 

 of, 112, 154; simple multicellular, 

 111; stimulation of, 161, 162, 163; 

 tubular. 111 



Glaucomys sabrinus, range of, 295, 298 



Glaucomys volans, range of, 295, 298 



Glenoid fossa, 138 



Glomerulus, 126, 152 



Glossozoa, 263 



Glottis, 123 



Glucose, 50, 53 



Glycerin, 52, 145. (See also Glycerol.) 



Glycerol, 40, 52, 53, 145; absorption of, 

 147. (See also Glycerin.) 



