InJ 



ex 



Page references in italic type refer to illustrations in text; those followed by t refer 



to tables. 



A-Z test, for pregnancy, 927 

 Abomasum, of cow or sheep, 623 

 Acetylocholine, 838 

 Acids, role of in egg activation, 218 

 Acipenser, reproductive and urinary ducts 

 of, 799 

 A. julvescens, xvii 

 A. sturio, cleavage in, 308, 309 

 Acoustico-lateral system, 813 

 Acraniata, xv 

 Acroblast, 126, 150 



in guinea pig sperm, 150 

 in human sperm, 150 

 multiple, in grasshopper, 750 

 Acrodont tooth, 607 

 Acrosome, 148 

 formation of, 150 

 role of in egg-sperm contact, 232 

 shapes and positions of, 143 

 Activation, of egg {see also Egg, activa- 

 tion of) 

 acids in, 217 

 artificial, 217 

 in Arbacia, 218 

 role of temperature in, 219 

 by strichnine, 218 

 complete, 212 

 fertilizin in, 225 



in hypertonic sea water, 217, 218 

 membrane formation during, 218 

 partial. 212, 217 

 of sperm, during fertilization, 212 

 Addison, Thomas, 882 

 Addison's disease, 882 

 Adeimann, H. B., 716 

 Adipose glands, 665 

 Adipose tissue, 658 



formation of, 664 

 Adrenal glands, 882 

 differentiation of, 883 

 role of secretions of in color change, 



594 

 structure of, 882 

 Adrenalin (Adrenaline), 838 

 Adrenaline (Adrenalin), 882 

 Aerial adaptations, of muscles, 708 

 After-birth, in human, 926 



Aftershaft, of feather, 571, 578 

 Agglutination, of egg during fertilization, 

 and sperm secretions, 230 

 of sperm, 225 

 Agglutinin factor, 225 



Air-bladder evagination, of pharynx, dor- 

 sal, 601 

 dorso-lateral, 601 

 Air sacs, cellular composition of, 649 

 formation of in chick embryo, 646 

 in bird group, 644 

 interclavicular, 647 

 intermediate, anterior, 647 

 posterior, 647 

 Alar plate, 820 



Albumen, deposition of in birds, middle 

 dense layer of, 905 

 outer liquid layer of, 905 

 Albumen-secreting region, in oviduct of 



bird, 905 

 Albuminous layer, of rabbit and opossum 



eggs. 303 

 Albuminous sac. of bird's egg, 905 

 Allanson, M., 46 

 Allantoic stalk, 911 

 Allantoic veins {see Veins, allantoic) 

 Allantois, 902, 908, 910 



fate of, 925 

 Allen, B. M., 883, 884 

 Alligator, ventricles of heart of. 704 

 Alligator mississippiensis, xviii 

 egg. characteristics of, 204t 

 fertilization, site of, 204t 

 sperm entrance into egg, place of. 204t 

 Allophores, 591 

 Alveolar ducts, 650 

 Alveolar sacs, 650 



Alveolus (Alveoli), of lung, structure of, 

 650 

 of jaw, 6 1 1 

 Ambystoma, effect of primordial germ cells 

 on gonad maturation in, 121 

 fate of pre-chordal plate mesoderm in, 



525 

 pineal organ of, 881 

 spermatheca of, 190 

 Ambystoma maculatum, equatorial plane 

 of cleavage in, 283 



933 



