INDEX 



Hemoglobin, 



in fetus, 277 



in pregnant women, 277 

 Hensen's node, 207, 209 

 Hepatic veins, 182 

 Hind brain (see Rhombencephalon) 

 Hindgut, 



in chick, 

 48-hr., 222 

 72-hr., 227 



derivatives of, 190, 191 

 Holoblastic cleavage, 1 1 5 

 Homologous function, in limbs, 1 56 

 Homology, of primitive streak with blas- 

 topore, 80, 206 

 Horizontal cleavage, 115 

 Hormones, 



chorionic gonadotropic, 260, 261 



estrone, 260, 261, 263 



follicle-stimulating, 22, 260, 261, 263 



gonadotropic, 18, 135 



in human fetus, 286, 288 



interstitial - cell - stimulating hormone, 

 22, 259, 261, 263 



in mammalian development, 261, 263 



progesterone, 260, 261, 263 



relaxin, 261, 262 

 Human development (see also Fetus, 

 human) , 



amnion formation in, 267 



blastocyst of, 266, 261 



cleavage in, 266 



at 8 weeks, 281 



endoderm formation in, 267 



erythroblastosis in, 277 



at 4 months, 285 



at one month, 278 



primitive streak in, 268, 269 



principles of, 293, 294 



at 6 weeks, 279. 280 



at 3 weeks, 274, 275, 276 



at 12 weeks, 283 



at 26 days, 276 



yolk sac formation in, 268 

 Human fetus (see Fetus, human) 

 Hydroids, 



polarity in, 231, 233 

 modification of, 233 



regeneration in, 232 



theories of regeneration in, 23 5 



two hydranths in one part of, 234 

 Hyoid cartilage, 188 



323 



Hypophysis (see also Pituitary gland), 

 in chick, 165, 166 

 in frog, 134, 135 



Immunity, 276, 293 



Implantation, of egg, 257, 260, 262 



Incubation, 



length of, 203 



temperature of, 204 

 Independent differentiation (see Self-dif- 

 ferentiation) 

 Induction, 



by chemical compounds, 84 



by dead tissues, 85 



of lens, 104 



of liver, 190 



mechanism of, 86 



of neural tube, 81 



of neuroblasts by limb, 153, 154 



by nucleo protein, 85 



of otocyst, 1 67 



of parts of spinal cord, 155 



of secondary embryo, 79 



of splanchnic mesoderm, 200 

 Inferior vena cava, 180, 181, 182 

 Infundibulum, 133, 165 

 Inner cell mass (embryonic knob), 266, 



267 

 Insulin, in dog fetus, 286 

 Intermediate mesoderm (nephrotome), 



in chick, 

 48-hr., 222 

 72-hr., 226 

 33-hr., 213 

 Intersex, in cattle twins, 282 

 Interstitial - cell - stimulating hormone 

 (ICSH or LH), 22, 23, 259, 261, 

 263 

 Intervillous space, 269 

 Intestinal caecum, 191 

 Invagination, 66, 125 

 Involution, 65, 125 



Labile organization, 



of adult organisms, 229, 230 



of heart, 101 



of hydroid, 233, 234 



of lens, 103 



of limb disk, 99 



in relation to twinning, 37 



of sea urchin, 33, 34 

 Lagena, 136 



