940 



Chen. G., 884 

 Chevron bones, 686 

 Chiasma (chiasmata), 134 



definition of, 137 

 Chick, blastoderm of, area opaca of, 357 

 area pellucida of, 357 

 cleavage in, 313, 315 

 delamination of hypoblast (entoderm) 



cells from, 359 

 presumptive organ-forming areas of, 

 360 



brain development in, 813 



circulatory system in, early development 

 of, 744 



dorsal aorta of, 743 



egg of, bilateral symmetry of, 162 



feather development in, 572 



feather pattern experiments with, 592 



gastrula of, mosaic distribution of de- 

 velopmental tendencies, 429 



gastrulation of, 420 



resume of morphogenetic cell move- 

 ments during, 426 



gut structures of, morphogenesis of, 604 



heart of, 753 



converging veins of, 746 

 early development of, 725 



independent pericardial wall develop- 

 ment in, 871 



inferior vena cava, development of, 746 



liver rudiment, development of. 623 



lung development in, 645, 645, 646 



mesonephros, development of, 781 



metanephric kidney, development of, 

 784 



migration of cells during gastrulation in, 

 423 



movements in epiblast layer of during 

 gastrulation, 426 



musculature associated with mandibular 

 visceral arch of, 717 



of 100 hours of incubation, special refer- 

 ence to nervous and urinary sys- 

 tems, 341 



of seventeen to nineteen pairs of som- 

 ites, sections of, 487 



of seventy-two to seventy-five hours of 

 incubation, 490, 542-544 



of twelve to thirteen pairs of somites, 486 



of twenty-seven to twenty-eight pairs of 

 somites, 488 



olfactory organ development of, 844 



ovarian development of, 797 



palatal conditions in, 615 



pancreas rudiments development of, 628 



pelvic girdle of, 689 



Chick — (Continued) 



pituitary and thyroid glands, effect of 

 on development of, 884 



post-gastrular development of, early, 480 



pre-primitive streak, early blastoderm of, 

 358 



pronephros, origin of, 776 



pulmonary diaphragm of, 872 



relation of embryonic chondrocranium 

 to adult skull, 678-679t 



skin, development of, 570 



testis, development of, 794 



tongue, origin of, 603, 608 



transverse sections of five pairs of som- 

 ites, 483 



tubulation of epidermal area in, 476 



twelve-day embryo, air sacs of, 645 



vertebrae, development of, 685 



vitelline and allantoic veins of, 742 

 Chief cells, of parathyroid glands, 879 



of pineal gland, 881 



of stomach mucosa, 621 

 Chief piece, of sperm flagellum, 149 

 Chiroptera, xx 

 Choana(ae), 844 



primitive, 844 



secondary, 844 

 Chondrichthyes, xvi 

 Chondrin, 659 



Chondriosomes, 126, 157 {see also Mito- 

 chondria) 

 Chondroblasts, 665 

 Chondroclasts, 667 



Chondrocranium, developmental stages of, 

 in Squalus acanthias, 669 



relation of to adult skull, of chick, 678- 

 679t 

 of frog, 616-6111 

 of human, 680-681t 

 Chondrocytes, 659 

 Chondrostei, xvii 

 Chordamesodermal canal, 417 

 Chordata, characteristics of phylum, xiv 



major divisions of phylum, xv 

 Chorio-allantoic membrane, 910, 924 

 Chorio-allantoic placenta, 917 

 Chorioid plexi, 822 

 Chorion, 162, 903, 908, 910 



in Styela, 162, 163 



true, 165 

 Chorion frondosum, 922 

 Chorion laeve, 921 

 Chorionic vesicles, in various mammals, 



924 

 Choroid coat, of eyeball, formation of, 849 

 Choroid fissure, 846 



of developing eye, 845, 846 

 Chromaffin cells, 882 



