322 



Frog — ( Continued') 



cleavage in, 113, 114 



embryo of, 130, 131, 132-138 



embryonic circulation in, 136 



embryonic excretion in, 138 



fertilization in, 113 



gastrula of, 111 



hatching of, 131,132 



larva of, 139 



metamorphosis in, 140 



neurula of, 126 



regeneration in, 232, 240, 241 



tadpole of, 140 



tailbud of, 126 

 Fucus egg, 



effect of light on, 298 



polarity of, 297 

 Function, 



development of, 157, 158 



homologous, 156 



in relation to differentiation, 157, 158 

 Fusion, of two eggs, 7, 9 



Gallbladder, 189, 190 



Galvanotaxis, in nerve development, 151 



Gamones, 5, 44 



androgamones, 44 



gynogamones, 44 

 Gastrula, 



of amphibian, 58 



of chick, 206, 207 



of frog, 1 1 7 



map of, 58, 60 



of sea urchin, 26 



of salamander, 118 

 Gastrulation, 63, 64 



in amphibian, 120-123 



in chick, 206, 207 



in frog, 1 17 



rearrangements during, 120-123 



in salamander, 7 78, 7 79 

 Genes, as cause of wingless chick, 296 



Rh, 292 

 Germ cells, origin of, 13, 201 

 Germinal epithelium, 



induction of, 201 



origin of, 200 

 Gill, formation of, 130, 131, 135 

 Gill plate (see Gill) 

 Glomerulus, in chick, 196, 797 

 Glomus (glomerulus), in frog, 7.57, 138 

 Glottis, 188 



INDEX 



Gonad (see Ovary and Testis) 

 Gonadotrophin (see Chorionic gonado- 

 tropic hormone) 

 Gonadotropic hormones, of pituitary, 18 

 Gray crescent, 56, 114 

 Gray matter, 162 

 Growth, 



cellular, 249 



chemical nature of, 249 



of chick blastoderm, 204, 20 5 



curves of, 7 7, 244, 245 



effect of differentiation upon, 248 



effect of food on, 245 



effect of oxygen, 246 



effect of volume on, 246, 247 



of egg, 14 



of embryonic tissues, 247 



energy source for, 253 



excretion during, 255 



of human fetus, 284 



logarithmic, 245 



in mammal, 257 



of microorganisms, 244, 245 



of organs, 248 



raw materials for, 251 



respiration during, 254 

 Gut, 



formation of, 728, 137 



in frog embryo, 737 

 Gynogamones, 44 (see also Gamones) 



Hair, of human fetus, 287 

 Hatching, 



changes at, 182-184 



of frog embryo, 737, 132 

 Hatching enzyme, in frog embryo, 132 

 Head process, 



in chick, 206, 207 



in human, 269 

 Heart, 



changes at hatching, 184 



in chick, 135 



field of, 702 



formation of, 176 



in human, 276 



onset of function of, 132 



in pig, 277, 272 



rate in embryo, 286, 287 



in tissue culture, 177 



transplantation of, 102 

 Heart rate, in human fetus, 286, 287 



