328 



INDEX 



Regeneration — {Continued) 



in salamander, 231, 232 



stimulus for, 240, 241 



theory of, 235, 236 

 Regression, of limb, 239, 240 

 Regulation (see Labile organization) 

 Relaxin, 261, 262 

 Release mechanisms, 



in differentiation, 50 



in organizer action, 86 



in ovulation, 24 

 Renal capsule (Bowman's capsule), in 



chick, 196, 197 

 Renal portal circulation, 



origin of, 180, 181 



regression of, 180, 181 

 Respiration, 



of chick embryo, 172 



and embryonic membranes, 255 



in frog development, 254 

 Respiratory movements, in human fetus, 



284 

 Retina, 133 



development of, 169, 170 



inverted structure of, 170 

 Reversed asymmetry, 191, 192 

 Rh factor, 276, 292 



Rhombencephalon (see also Hindbrain), 

 213 



in chick, 21 3 



in frog embryo, 135, 136 

 Rhythmic contraction, 



of amnion, 173, 201 



of heart, 177 



of uterus muscle, 260 



Salamander, 



blastulaof, 118 



cleavage in, 115, 116 



embryo of, 130, 131 



gastrula of, 118 



larva of, 709 



limb regeneration in, 232, 237 



neurula of, 127 

 Sclerotome, 137 



in chick, 72-hr., 216 



differentiation of, 194, 195 

 Sea urchin egg, 



animal halves of, 29 



centrifuging of, 30 



labile organization, 33, 34 



microdissection of, 29, 34 



Sea urchin egg — (Continued') 



normal development of, 25, 26 



pluteus of, 28 



polarity of, 27 



vegetal halves of, 29 

 Secondary embryo, 78, 79 

 Secondary neural plate, 78 

 Secretion, in human fetus, 286, 287, 288 

 Self-differentiation, 94 



of chick blastoderm, 209 



of eye, 95 



of femur, 105 



of forelimb, 93 



of heart, 94 



of nasal pit, 94 



of otocyst, 94 

 Self-duplication, 



of cellular elements, 250, 251 



of a nucleoprotein, 250 



of a virus, 250 

 Semen, 53 



sperm content of, 229 

 Semicircular canals, 136, 167 

 Sense organs, 167-170 



of human fetus, 288 

 Sensory layer of retina, 1 34 

 Sensory nerves, of spinal ganglia, 160, 



161 

 Separation of blastomeres, 



in amphibian, 56 



in sea urchin, 8 

 Sex determination, 299, 300 

 Sex differentiation, 299, 300, 301 



effect of epiphysis on, 166 

 Sex reversal, 



in chick, 300, 301, 302 



in frog, 302 



in hen, 303 



in toad, 303 

 Sexual cycle, 



in frog, 17, 113 



in mammals, 20 



in raccoons, 18 

 Sexual photoperiodicity, 18, 19 

 Sheath cells, 159, 160 

 Shell (of egg), 204 

 Sinus venosus, in chick, 



48-hr., 216 



72-hr., 225 

 Situs inversus, 191, 192 

 Smooth muscle, of viscera. 200 



