INDEX 



321 



Environmental factors, in development, 



112 

 Enzymes, 



for growth, 249, 252 



hatching, 132 



in human fetus, 286 



in liver, 182 

 Ependymal layer, 162 

 Epiboly, 65, 125 

 Epididymis, in chick, 198 

 Epigenetic theory, 5, 27 

 Epimyocardium, 176, 211, 214 

 Epiphysis, 133, 165, 166 

 Epithelial bodies, 188 

 Equal cleavage, 115 

 Erythroblastosis, in human, 277 

 Esophagus, 188 

 Estrone, 



action on uterus, 260, 261, 263 



effect on chick embryo, 300, 302 



effect on sex, 277 

 Estrus cycle, 259 

 Eustachian tube, 188 

 Evagination, 66 

 Evolution, 



of circulatory system, 177 



of kidney system, 178, 199 

 Excretion, 



in chick, 172, 196, 198, 201, 255 



in frog, 138 



in human fetus, 283 

 Excretory system, relation to circulatory 



system, 178 

 Exogastrula, 66, 61 

 External gills, of frog, 139 

 Extraembryonic area, 215 

 Extraembryonic coelom, 



in chick, 48-hr., 221 

 Extraembryonic membranes, 



in chick, 201 



circulation in, 174 



formation of, 172-174 



function of, 172 

 Eye (see also Optic vesicle) , 



development of , 103, 167, 169, 170 



in frog, 133, 134 



in human, 280, 282, 287 



in pig, 10-mm., 272 



Fats (lipids), in growth, 253 

 Fertilization, 

 in frog, 17, 113 



Fertilization — (Continued) 



gamones in, 44, 45 



membrane, 46 



metabolic changes at, 47 



theory of, 49 

 Fertilization cone, 46 

 Fertilized egg, 46 

 Fetal zone, of adrenal gland, 288 

 Fetus, human, 



birth of, 289-294 



blood formation in, 288 



circulation of, 290, 291 



descent of testes in, 287 



digits of, 283, 285 



8-week, 281 



enzymes of, 286 



fetal zone in adrenal gland of, 288 



4-month, 



excretion in, 283 



reflexes of, 280, 283, 284, 285 



secretion in, 286, 287, 288 



hair of, 287 



heart rate of, 286, 287 



hormones of, 286, 288 



mammary glands of, 287 



nails of, 283, 287 



premature birth of, 288, 289 



respiratory movements of, 284 



sense organs of, 288 



suprarenal cortex of, 277, 282 



swallowing reflex of, 286-287 



12-week, 283 

 Fields, 93 



heart, 102 



limb, 98 



otocyst, 102 



polarity of, 98 



properties of, 101 

 Follicle, ovarian, 21, 258 

 Follicle-stimulating hormone, 22, 259, 



261, 263 

 Foramina, of heart, 182, 183 



partial closure of, 184 

 Forebrain (see Prosencephalon) 

 Foregut, 



in chick, 209,220, 211 



derivatives of, 187, 188 



formation of, 185, 186, 209, 210, 211 

 Friedman test, 23 

 Frog, 



blastulaof, 117 



breeding habits of, 112 



