INDEX 



935 



Andrenosterone, 27 



Andrews, F. N., 195 



Androgamic substances (androgamones), 



228 

 Androgen(s), 21 

 site of, 27 

 synthesis of, 27 

 Androgenesis, 263 



Androgenic zone, of adrenal gland, 883 

 Andromerogony, 265 

 Androsterone, 21-22 

 Anestrus, definition of, 94 

 Angioblast theory of primitive blood vessel 



development, 730, 731 

 Animal breeding, and sperm survival, 198 

 Animal pole of egg of higher mammals, 



determination of, 299 

 Animalculists, 56 



Anisotropic substance, definition of, 703 

 Ankylosis, 695 



during development of skull bones, 695 

 of frontal bones, 695 

 Anolis carolinensis, xviii 

 Anseriformes, xix 

 Anticoagulating substance of blood in cy- 



clostomatous fish, 617 

 Antifertilizin, 225, 227 



sperm, 230 

 Antilocapra americana, pronghorn ante- 

 lope, horns of, 586 

 Antipernicious-anemia factor, 875 

 Antlers, loss of "velvet," 28 



shedding of, 28 

 Antrum, of mature Graafian follicle, 71, 



74 

 Anura, xviii {see also Amphibia, anuran) 

 Anus, formation of, in Amphioxus embryo, 



502 

 Aorta(ae), dorsal, 727 

 branches of, 764 



development of, 760 

 lateral arterial, 762 

 ventral arterial, 762 

 Aortal arch (arches), afferent system of, 

 760 

 efferent system of, 760 

 mandibular, of chick embryo, 743 

 modifications of, during embryonic de- 

 velopment, 759 

 in various vertebrates, 760, 762 

 within visceral arches, 619 

 Apical body {see Acrosome) 

 Apis mellifica, natural parthenogenesis in, 



216 

 Aponeurosis, pulmonary, of chick, 872 

 Appendages, bilateral, of long bones, de- 

 velopment of, 692 

 paired, 690 



Appendages — (Continued) 

 bi\a\QT?L\—{C ontinued) 

 paired — (Continued) 



appendicular skeleton, development 



of, 690 

 development of, early, 508 

 development of musculature of, 718 

 types of, 691 

 median unpaired, 690 

 Apteria, 573 

 Apteryx, kiwi, xix 

 Aqueduct of Sylvius, of brain, 823 

 Arachnoid layer, 821 



Arbacia, sea urchin, artificial activation of 

 egg in, 218 

 egg water of, 225 



fertilization membrane separation in, 

 237 

 Arbacia pustulosa, fertilizin of, 225 

 Archaeornithes, xix 

 Arcualia, 682 



Area opaca, of chick blastoderm, 357 

 Area pellucida, of chick blastoderm, 357 

 Areolae, 925 

 Aristotle, 905 

 Armadillo, dermal bony armor of, 697 



polyembryony in, 383, 384 

 Aronson, L. R., 59 

 Arteriovenous system, 726 

 basic plan of, 726 

 development of, 726 

 Artery(ies), carotid, internal, 727, 760 

 central, of retina, 846 

 coeliac, 762 

 development of, 732 

 genital, 762 



intersegmental, dorsal, 760 

 lateral, 762 

 lumbar, 760 

 Arthrosis, 695 



Artificial parthenogenesis {see Partheno- 

 genesis, artificial) 

 Artiodactyla, xx 

 Ascaphus, 4 

 Ascaphus truei, xviii 



intromittent organ in, 790 

 sperm transport by means of cloacal tail, 

 189 

 Ascaris, cell lineage in, 331 

 chromatin diminution of, 116 

 fertilization, stages of, 265 

 separation of fertilization membrane in, 

 237 

 Ascaris megalocephala, continuity of Keim- 

 bahn in, 1 17 

 egg maturation in, 214 

 fertilization in, 214 

 Aschheim, S., 40, 926 



