INDEX 



941 



Chromaffin reaction, 882 



Chromatid, 132 



Chromatin, diminution of, in Ascaris, 116 



in Miastor, 118 

 Chromatophores, 591 

 origin of, 557, 560 



role of in producing skin-color effects, 

 591 

 Chromatophoric activity, environmental 

 control of, 594 

 genetic control of, 592 

 hormonal control of, 593 

 Chromidia, during fat formation, 664 

 Chromosomal mechanisms, for sex deter- 

 mination, 887 

 Chromosome(s), accessory, 215 

 bivalent, 132 



homologous, definition of, 130 

 "lamp-brush," 136, 142 

 reduction of, 145 

 sex, 887 

 tetrad, 132 

 twin, 132 

 Chrysemys picta, turtle, blastoderm of dur- 

 ing gastrulation, 418 

 female, reproductive organs of, 192 

 sperm transport in female, 191 

 zona radiata of, 166 

 Cilia, distribution of in peritoneal cavity of 

 adult female frog, 201 

 peritoneal, of Runa pipiens, 195 

 pro-ovarian, 191 

 Ciliary action, and external migration of 



the egg, in frog, 201 

 Ciliary body formation, of developing eye, 



845 

 Ciliary ganglion, of oculomotor nerve, 828 

 Ciona, early cleavage planes in, 287 

 Ciona intestinalis, xv 

 Circulation, fetal and postpartum, 928 

 Circulatory system, 724 

 definition of, 725 

 histogenesis of, 730 

 in mammalian fetus, modifications of at 



birth, 766 

 in relation to nutrition, 927 

 major subdivisions of, 726 

 morphogenesis of, 73,6 

 Circulatory tubfcs, primary, 463 

 Citellus tridecemlineatus 



{see Ground squirrel) 

 Claude, A., 159 



Clavelina. early cleavage planes in, 287 

 Clavicle, 693 



of intramembranous origin, 693 

 Claws, development of. 584 

 diagrams of. 583 

 in reptiles, 570 



Cleavage, cytoplasmic substances, influence 

 of, 284 



definition of, 280 



determinate definition of, 287 



egg organization, influence of, 284 



equatorial plane of, 283 



factors involved in, 284 



functions of, 333 



geometrical relations of, 283 



history of, early, 281 



holoblastic, 288 



transitional or intermediate type, 305 



in Ambystoma maculatum (punctatum), 

 305, 306 



in Amia calva, 309, 310 



in Amphioxus, 288, 290, 342 



latitudinal plane of, 284 



meridional plane of, 283 



meroblastic, 288 

 definition of, 312 



qualitative, 336 



influence upon later development, 334 



quantitative, 336 



influence upon later development, 334 



superficial, 288 



suppression of, by heparin, 219 



transitional or intermediate, definition, 

 305 



types of, 288 



vertical plane of. 283 



viscosity changes during, 286 

 Cleavage-blastuiar period, importance of, 



281 

 Cleavage laws, 286 

 Cleavage path, 247 

 Cleavage planes, relation of to antero-pos- 



terior axis of embryo, 286 

 Clemmys guttata, xix 

 Clemmys leprosa, formation of hypoblast 



in, 361 

 Cloaca, 18, 772 



area of, diverticula of, 602 



diff'erentiation of, 787 



glands of, 189 



presence of in vertebrate group, 788 



primitive, divisions of in mammals, 715 

 Cloacal septum, 787 

 Closing folds, dorsal, 861, 867 

 Coccyx, 686 



Cochlear duct, 557, 854, 855 

 Coelenterates, gemmation in, 55 

 Coeloblastula, definition of, 341 



typical, basic structure of, 342 

 Coelom. definition of, 857 



extra-embryonic, 909 

 Coelom formation, 490, 492 

 Coelomic cavities, 857 



formation of, in mammals, 868 



