954 



INDEX 



Heart — (Continued) 



converging veins of, 736 



development of, 726, 728, 747, 750 



early embryonic, fate of divisions of in 

 various vertebrates, 758t 



embryonic, divisions of, 747 



mammalian, converging veins of, 747, 

 748 



primitive embryonic, histological struc- 

 ture of, 748 



valves of, in check, 756 



ventricles of alligator, 704 

 Heart beat, contraction wave of, 754 



initiation of, 766 

 Heat, effect upon sperm formation, 36 

 Hedgehog (Erinaceus europeus), descent of 

 testes in, 7 



female guarding young, 929 

 Heilbrunn, L. V.. 217, 237, 271, 286 

 Heloderma suspectum (Gila Monster), 



xviii 

 Hemal arches, 688 

 Hematopoiesis (Hemopoiesis), 732 

 Hemicentetes semispinosus, Madagascan in- 



sectivore, blastula of, 366 

 Hemichordata, subphylum, xv 

 Hemochorial placenta, 918 

 Hemocytoblast, 733 

 Hemoendothelial placenta, 918 

 Hemoglobin, 735 



Hemopoiesis (Hematopoiesis), 732 

 Hen, effect of progesterone on ovulation, 

 80 



egg, germinal disc of, 313 



first cleavage plane in egg of, 287 



maturation and fertilization in egg of, 

 252 



sperm transport in, 191 

 Henle, layer of in hair, 583 

 Hensen's membrane, 702 

 Hensen's node, formation of in pig gas- 



trula, 433 

 Heparin, suppressed cleavage by, 219 

 Hepatic portal system, of chick embryo, 



745, 746 

 Hepatic portal vein, 737 

 Hepatic veins, 738, 743 

 Hepaticae advehentes, 738 

 Hepaticae revehentes,'7i5 

 Hepato-duodenal ligament, 873 

 Hermaphroditic species, 886 

 Hershkowitz, S. G., 563 

 Hertig, A. T., 920 

 Hertwig, O., 214. 239 

 Hertwig, R., 218 

 Hertwig's laws of cleavage, 286 



Heterandria formosa, characteristics of egg, 

 site of fertilization, and place of 

 sperm entrance into egg, 204t 

 egg retention of, 915 

 fertilization in, 199 

 ovarian fertilization in, 197 

 Heterogametic sex, 887 

 Heuser, C. H., 305, 432 

 Hibbard, H., 187 

 Hildebrand, S. F., 197 

 Hill, C, 812, 57i 

 Hill, E. C, 11 



Hill, J. P., 197, 200, 305, 362, 363, 904 

 Hill, M., 44 

 Hilus, of ovary, 58 

 Hindbrain, 812 

 Hindgut, 481, 600 



junction with midgut, diverticula of, 601 

 Hippocampus, male egg pouch of, 915 

 His, Wilhelm. 731 



enunciation of principle of organ-form- 

 ing germ-regions, 343 

 recesses of, 863 

 Hisaw, F. L., 40, 103 

 Histochemistry, xii 

 Histogenesis, definition of, 517 

 Histology, definition of, 517 

 Histotrophic nutrition, 921 

 Hoagland, H., 198 

 Hochstetter, F., 738, 746 

 Holoblastic cleavage, 288 

 Holobranch, definition of, 638 

 Holonephros, definition of, 772 

 Holostei, xvii 

 Holz-Tucker, M., 59 



Homo sapiens (man), characteristics of 



egg, site of fertilization, and place 



of sperm entrance into egg, 207t 



Homogametic sex, 887 



Homologous chromosomes, definition of, 



130 

 Homology, basic, of vertebrate organ sys- 

 tems, 545 

 definition of, 545 

 Homonculus, 54, 56 

 Homoplasy, 551 



Honeybee, natural parthenogenesis in, 216 

 Hoofs, development of, 584 



diagrams of, 583 

 Hopkins, M. L., 884 



Hormonal control, of ovulation, in lower 

 vertebrates, 80 

 of ovulatory process, 78 

 Hormones, estrogenic, estradiol, 85 

 estrone, 85 

 in ovary of hen, 73 

 influence upon sperm transport in ovi- 

 duct, 197 



