INDEX 



943 



Crop, of chick, 623 



Crossing over, phenomenon of, 133, 135 



Crotalus horridus, rattlesnake, xix 

 oral glands of, 616 



Crown, of tooth, 605 



Cryptohranchus, external gills of, 639 



Cryptobranchus alleganiensis, xvii 

 respiratory surfaces of, 636 



Cumulus oophorus, of mature Graafian 

 follicle, 71, 74 



Cuneus, of hoof of horse, 585 



Cup-shaped valves, of chick heart, 756 



Cushion septum, of chick heart, 754 



Cuspid valves, development of in mam- 

 malian heart, 757 

 of chick heart, 756 



Cutaneous field, general, 842 



Cuticle, of hair shaft, 582 



Cytochemistry, xii 



Cytogenesis, definition of, 517 



Cytolysis, 221 



Cytomorphosis, definition of, 517 



Cytoplasm, germinal, 116, 117 



Cytoplasmic changes, of developing neu- 

 rons, 814 



Cytoplasmic extensions, from nerve cell 

 body, 814 



Cytoplasmic inequality, of cleavage blasto- 

 meres, 328 



Cytoplasmic segregation, during fertiliza- 

 tion, in Styela, 245 



Cytotrophoblast, 920 



D 



Dalcq, A. M., 270, 893 

 Dasyurus, superficial implantation in, 916 

 Dasyurus novemcinctus, egg, characteris- 

 tics of, 206t 



fertilization, site of, 206t 



sperm entrance into egg, place of. 206t 

 Dasyurus viverrinus (Australian marsupial 

 cat), early blastular conditions 

 of, 304 



egg, characteristics of, 205t 



fertilization, site of, 205t 



inner cell mass of blastocyst of, 304 



sperm entrance into egg, place of, 205t 



sperm survival in female genital tract, 

 197 

 Dean, B., 309, 310, 311, 444, 458, 639 

 Deansley, R., 46 

 De Beer, G. R., 682. Ill 

 Decidua basalis, 921 

 Decidua capsularis, 921 

 Decidua parietalis, 921 

 Decidua vera, 921 

 Deciduous teeth, 613 



Deep profundus, division of trigeminal 



nerve, 828 

 Deer, Odocoileus virginianus borealis, ef- 

 fect of testosterone on, 27 

 spermatogenesis in, 23 

 testicular activity in relation to sea- 

 sons, 24 

 white-tailed, antler of, 586 

 Definitive body form, xii {see also Body 



form, definitive) 

 Definitive state, of germ cell, 113 

 de Graaf, Reinier, 5, 5 



early description of egg follicles, 71 

 Dehydroisoandrosterone, 22 

 Delamination, in gastrulation, 390 

 definition of, 398 

 of three germ layers in teleost fishes, 438 

 Demersal eggs, 251 

 De Meyer, J., 223 

 Demibranch, definition of, 638 

 Dendrites, 814 

 Dental lamina, 609 

 Dental papilla, 61 1 

 Dentinal fibers, of odontoblasts, 611 

 Dentine, of teeth, 605, 611 

 substance similar to, in shark embryo, 

 563 

 Dentition, types of, 607 

 Dependent differentiation, definition of, 375 

 Dermatome, 507, 711 

 Dermatomic fold, 507 

 Dermis, 556 



development of in chick, 573 

 embryonic rudiment of, 530 

 structures of in Necturus, 567 

 Dermo-myotome, 526 

 De Robertis, E., 43 

 Deroceras laeve, formation of polar bodies 



in, 214 

 Descartes, 881 

 Desmocranium, 671 

 Desmognathus, muscles of, 707 



spermatheca of, 790 

 Desmognathus fuscus, xvii 

 Desoxyribose nucleic acid, 815 

 Determination, in differentiation, definition 

 of, 378 

 positional or presumptive, 378 

 rigid, in early Styela blastomeres, 330 

 rigid or irrevocable, definition of, 378 

 Deutoplasm, formation of, 157 

 Developing body, mesodermal contribu- 

 tions to, 524 

 Development, definition of, xi 



environmental conditions necessary for, 

 901 



