320 



INDEX 



Cytoplasmic inheritance, in differentiation, 

 87 



Dedifferentiation, 



nature of, 238, 239 



role of nerves in, 239, 240 



in salamander limb, 237, 238 

 Degeneration, 



of limb, 158, 239 



of mesonephros, 199 



of nerve fiber, 145, 146 

 Dermatome, 137 



of chick, 72-hr., 216 



differentiation of, 194, 195 

 Dermis (see Corium) 

 Determination, of limb, 92 

 Development, effect of genes upon, 296- 



299 

 Diencephalon, 165 



in chick, 



48-hr., 216, 218, 219 

 72-hr., 223, 224, 225 



in pig, 271,272 

 Differential permeability, of placenta, 277 

 Differentiation, 



cytoplasmic inheritance in, 87 



of ear, 167, 168 



of eye, 103, 167, 169, 170 



of heart field, 102 



of limb blastema, 238 



of limb field, 105 



of motor region of cord, 162 



of neural crests, 160, 161 



of neuroblasts, 143 



of olfactory organ, 168 



of optic nerve, 144 



of parts of spinal cord, 155 



in relation to function, 157, 158 

 Digestion, in chick embryo, 172 

 Digestive system, 



early development of , 185, 186 



inducing factors of, 192 



yolk sac formation in, 186 

 Digits, in human, 280, 282, 283 

 Dorsal aorta, 173, 179 



in chick, 



48-hr., 218, 220 

 72-hr., 224, 225, 226 



in frog, 135, 137 

 Dorsal aortic roots, 134 

 Dorsal horn, 162 

 Dorsal lip, 63, 124 



Dorsal lip — (Continued) 



in frog, 117 



in salamander, 118 

 Dorsal mesocardium, 213 

 Double embryo, 6 

 Dual function, 



in adrenal, 166, 199 



in hypophysis, 165, 166 

 Dual innervation, 163 

 Ductus arteriosus, 183, 184 

 Ductus cochlearis, 167 

 Ductus vencsus, 182, 216 

 Duplication, 35 



of heads, 7, 36 

 Dynamic equilibrium, 230 



Ear (see Otocyst) 



Efferent branchial artery, 135, 136 



Egg, 



length of life of, 51 

 size of, 1 5 

 transport of, 16 

 Embryo, 

 of chick, 

 48-hr., 221 

 72-hr., 224-227 

 33-hr., 214 

 of frog, 130, 131-138 

 of human, 



8-week, 281, 282 

 one-month, 278 

 6-week, 279, 280 

 3-week, 274, 275 

 26-day, 276 

 of pig, 10-mm., 271 

 of salamander, 130, 131 

 Embryonic disk, 268 

 Embryonic induction, 79 

 in amphibia, 78 

 in birds, 81 

 definition of, 82 

 of lens, 103 



of neuroblast differentiation, 1 53, 154 

 of splanchnic mesoderm, 192 

 Embryonic knob (see Inner cell mass) 

 Encasement theory, 4 

 Endocardial vesicles, 176 

 Endocardium, 176, 111, 213, 220 

 Endolymphatic duct, 136, 168 

 Energy source, 

 for growth, 253 

 in human development, 277 



