754 



SUBJECT INDEX 



during, ib. ; kidney during, ib. ; heart 

 during, ib. ; urine during, ib. ; respira- 

 tion during, ib. ; brain during, ib. sq. ; 

 production of spermatozoa during, 720, 

 727 ; in horse, 721 



Seps, formation of corpus luteum in, 145 

 Seps chalc.ides, yolk-sac in, 415 



Serine, 288, 304 



Serotina, 398, 401 ; of mouse, 469 

 Serum, composition of ash of, in dog, 595 



Sex-differentiation in Bonellia, 692 

 Sex-determination, 11, 20 \, 296, 331; 

 Chapter XV. ; classification of theories 

 of, 662 ; in frog, 662 sq., 668 ; influence 

 of food on, 662 sqq. ; in Amphibia, 663 ; 

 in lamprey, 664 ; in Lepidoptera larvae, 

 ib. ; in fly larvae, ib. ; in bees, ib. sqq. ; 

 in termites, 665 ; in Nematus ventri- 

 cosus, ib. sq. ; in Crustacea, 666 ; 

 effect of fertilisation on, ib. sq. ; in 

 Hymenoptera, 667 ; in saw-flies, ib. ; 

 in Hydatina, ib. ; in Hydatina senta, 

 668 ; in cattle, ib. ; effect of time of 

 fertilisation, ib. sq. ; in man, 668 ; 

 in toad, 669 ; influence of nutrition 

 and environment on, ib. sqq. ; by 

 maturity of ovum, 669 ; in rats, ib. ; 

 in mice, ib. ; in plant-lice, ib. ; by 

 sexual gametes, 671 sq. ; in Tal&poria 

 tubulosa, 671 sq. ; by dimorphism of 

 spermatozoa, 672 ; in Anasa trisiis, ib. ; 

 in Galgulus oculatus, 673 ; XY type of, 

 674 ; in Drosophila, ib. ; in phyl- 

 loxerans, ib. n. ; in Datura, 675 ; 

 WZ type of, 678 ; in Lepidoptera, 678 ; 

 in birds, ib. ; in Myriapods, ib. ; in 

 Nematodes, ib. ; in spiders, ib. ; in 

 Mammalia, ib. ; in Praopus hybridus, 

 679 ; in Simocephalus, 681 ; effect of 

 age of parents on, 683 sq. ; effect of 

 parental vigour on, 684 ; effect of nutri- 

 tion on, 684 sqq. ; in pigeons, 685 sq. 



Sex-linked characteristics, in Drosophila 

 ampelophila, 675 sq. ; in Abraxa 

 grossulariata, 676 ; in Abraxas lacticolor, 

 ib. ; in canaries, 677 ; in fowl, ib. 



Sex-metabolism in Inachus, 691 



Sex-ratio, in man, 662 ; in Todas, ib. ; in 

 France, 687 ; in Russia, ib. ; in Sweden, 

 ib. ; in London, ib. 



Sex-reversal, in Crepidula fornicata, 692 ; 

 in Crepidula, plana, ib. ; in Triton 

 alpestris, 693 ; in frog, ib. 



Sexual activity in male, 170 



Sexual attraction in Dacus, 12 



Sexual characters, secondary, 25 



Sexual inversion, 691 



Sexual latency, 688 sqq. 



Sexual organs, biochemistry of, Chapter 

 VIII. ; relation of thyroid to, 384 



Sexual rest, energy requirements during, 

 519 



Sexual season, definition of, 32 



Sheep, breeding season in, 24 ; dicestrous 

 cycle in, 34 ; cestrous cycle in, 39, 42 



sq. ; practice of flushing in, 41, 634 

 sq. ; uterine cycle in, 103 ; uterine 

 mucosa in, 105 ; ovulation in, 131 ; 

 formation of corpus luteum in, 141 sq., 

 146 ; form of spermatozoa in, 169 ; 

 in- breeding in, 218 ; ampulla of Henle 

 in, 240 ; effect of castration in, 323 

 sq. ; ovum of, 404 ; prochorion of, 

 406 ; yolk-sac in, 415, 420 ; blasto- 

 cyst of, 421 ; placenta of, 428 sqq., 

 449, 509 ; blastodermic vesicle of, 

 430 ; foetal villi of, 431 ; histology 

 of placenta of, 435 ; fcetal nutrition in, 

 456 ; trophoblast of, 464 ; fixation of 

 blastocyst in, 509 ; laevulose in foetus 

 of, 537 ; blood of, during pregnancy, 

 556 ; uterine contraction in, 562 ; 

 udder of, 586 ; size of litters in, 623 ; 

 fertility in, 632 sqq., 696 sqq. ; barren- 

 ness in, 633 ; effect of food on fertility 

 in, 634 ; share of ram in fertility of, 

 635 ; inheritance of fertility in, 642 

 sq. ; causes of abortion in, 655 ; fcetal 

 atrophy in, 656 ; growth of, 707 

 sqq. ; puberty in, 714 ; menopause in, 

 717 ; longevity in, 723. See also Ovis 

 species 



Shrew, cestrous cycle in, 55 ; formation of 

 corpus luteum in, 139, 145 ; placenta 

 of, 409, 481 sqq. ; yolk-sac in, 424; 

 placenta of, 481 sqq.; blastocyst of, 481; 

 trophoblast of, ib. sq. ; omphaloidean 

 syncytium of, 482 ; cytoblast of, ib. ; 

 plasmodiblast of, 483 ; embryo of, ib. 



Siderophores, 448 



Silkworm, effect of castration in, 325 



Silver-sided minnow, see Menidia 



Simiidse, placenta of, 408 



Simocephaliis, parthenogenesis in, 670 ; 

 sex-determination in, 681 



Sinus ensiformis, 425 



Sinus terminalis, 412 



Siphostoma floridoe, marsupium of, 690 



Sirenia, placenta of, 408 sq., 410, 442 ; 

 position of mammary glands in, 586 



Skin in pregnancy, 559 



Sloth, position of mammary gland in, 586 



Snake, phenomena associated with breed- 

 ing in, 28 



Snipe, mating habits of, 25 



Sodium, in egg of fowl, 278 ; in foetus of 

 man, 547 ; in milk, 594 ; in ash of pup, 

 595 ; in milk of dog, ib. ; in serum -of 

 dog, ib. 



Soma, effect of, on germ-cells, 208 sqq. 



Somatic stalk of yolk-sac, 415 



Somatopleur, 412 ; of bat, 489 



Sorex, see Shrew 



Size of offspring in relation to food 

 supply, 522 



Sparrow, breeding season in, 22 ; f ollic- 

 ular atresia in, 152 sq. 



Sperm agglutination, in Nereis, 186 ; in 

 Arbacia, ib. 



Spermatid, 162 sq. ; in man, 163 



