4ilJ 



rUINCIFLES OF ANIMAL BIOLOGY 



Food vacuole, 101 

 Foot, of Hydra, 71, 72 

 Formations, in paleontology, 329 

 Fossils, 325-348 



as evidence of evolution, 351, 352 



index, 329 



nature of, 326, 327 



preservation of, 325-328 



tracks, 327, 328 

 Fowls, heredity of combs of, 231, 232 

 Fresh-water habitats, 294-300 

 Frog, 277 



cleavage in. 201 



digestive system of, 102, 103 



metamorphosis of, 214. 215 



nervous system of, 141, 142 



tadpole, 191 



G 



Galen, 6-8 



Gall bladder, 101, 103 



Gamete, 159, 173 



Ganglion, 141, 146, 147, 212 



Garter snakes, distribution of, 315, 316 



Gastropoda, 271, 272 



Gastrovascular cavity, 80, 101 



of Hydra, 73 

 Gastruia, 73, 204, 206 

 Gastrulation, 204, 205, 206 



of sponges, 262 

 Gemnuile, of sponge, 170 

 Genes, 62, 224 



choice of symbols for, 227 



interaction of, 231, 232 



nature of, 238 

 Cienetics, 18-21, 222-243 



history of modern, 223, 224 



n)echanism of, 224, 225 



practical applications of, 238-240 



problems, 240-243 



of sex, 233, 234 

 Genus, 245, 248 

 Geoffroy St. Hilaire, 14 

 Geographic distribution, 307-324 



affected by kinship, 315, 316, 317 



as evidence of evolution, 352 



major r(>alms of, 323, 324 



•world-wide scheme of, 321-324 

 (ieol()gic;il time; scale, 330 

 ( Jephyrea, 276 



Germ cells, 71 



early marks of. 203, 204, 205 



in insect egg, 73 



maturation of, 193-198 



origin of, 205 

 CJerm layers, 206, 207 

 Gill, 114, 115 



analogy of, 251, 252 

 Gill bar, 210, 211 

 Gill cleft, 209, 211 

 Gill pouch, 209, 211 

 Gizzard, of earthworm, 101, 102 

 Glands, digestive, 102, 103 



in frog tongue, 102 



types of, 84 

 Glaucomys, distribution of, 313, 314, 31. j 

 Glenoid fossa, 92, 93 

 Glomerulus, 135, 136, 137 

 Glossozoa, 247 

 Glottis, 115 

 Golgi body, 26, 27, 28 

 Gonad, 80, 81 



migration stimulated by, 318 

 Gonangium, 173 

 Goniatite, 344 



suture of, 343 

 Gonionenuis, 263 

 Gonoduct, 80 

 Gonophofe, 174, 175 

 Gonotheca, 173 

 Grant ia, collared cells in, 52 

 Graptolite, 331 

 Gregaloid colony, 67, 68 

 Grew, Nehemiah, 10 

 Grov.'th, 46, 50 

 Guinea pigs, heredity in, 226, 228, 229 



H 



Haglish, 276 

 Haly^ites, fossil, 327 

 Harvey, William, 8, 9. 20 

 Heart, 122, 123, 128 



four-chambered, 124 



regulation of beat of, 127, 128 



two-chambered, 123 

 Heat, as cause of nuitation, 357 



produced by oxidation, 120 



regulation of, 120, 121 

 Ih^lium atom, 32 

 Hemoglobin, 127 



