nd pasture, i. 96, 97;
periods of gestation of, i. 97;
effect of heat on the fleece of, i. 98-99, ii. 278;
effect of selection on, i. 99-101;
"ancon" or "otter" breeds of, i. 17, 92, 100;
"Mauchamp-merino," i. 100-101;
cross of German and merino, ii. 85-89;
black, of the Tarentino, ii. 227;
Karakool, ii. 278;
Jaffna, with callosities on the knees, ii. 302;
Chinese, ii. 315;
Danish, of the bronze period, ii. 427;
polydactylism in, ii. 14;
occasional production of horns in hornless breeds of, ii. 30;
reversion of colour in, ii. 30;
influence of male, on offspring, ii. 68;
sexual differences in, ii. 73;
influence of crossing or segregation on, ii. 86, 95-96, 102-103;
interbreeding of, ii. 119-120;
effect of nourishment on the fertility of, ii. 111-112;
diminished fertility of, under certain conditions, ii. 161;
unconscious selection of, ii. 213;
natural selection in breeds of, ii. 224, 225, 227;
reduction of bones in, ii. 242;
individual differences of, ii. 251;
local changes in the fleece of, in England, ii. 278;
partial degeneration of, in Australia, ii. 278;
with numerous horns, ii. 291;
correlation of horns and fleece in, ii. 326;
feeding on flesh, ii. 303;
acclimatisation of, ii. 305-306;
mountain, resistance of, to severe weather, ii. 312;
white, poisoned by _Hypericum crispum_, ii. 337.
SHEEP dogs resembling wolves, i. 24.
SHELLS, sinistral and dextral, ii. 53.
SHERIFF, Mr. new varieties of wheat, i. 315, 317;
on crossing wheat, ii. 104-105;
continuous variation of wheat, ii. 241.
SIAM, cats of, i. 47; horses of, i. 53.
SHIRLEY, E. P., on the fallow-deer, ii. 103, 120.
SHORT, D., hybrids of the domestic cat and _Felis ornata_, i, 45.
SIBERIA, northern range of wild horses in, i. 52.
SICHEL, J., on the deafness of white cats with blue eyes, ii. 329.
SIDNEY, S., on the pedigrees of pigs, ii. 3;
on cross-reversion in pigs, ii. 35;
period of gestation in the pig, i. 74;
production of breeds of pigs by intercrossing, i. 78, 95;
fertility of the pig, ii. 112;
effects of interbreeding on pigs, ii. 121-122;
on the colours of pigs, ii. 210, 229.
SIEBOLD, on the sweet potato, ii. 309.
SIEBOLD, von Carl, on parthenogenesis, ii. 364.
_Silene_, contabescence in, ii. 166.
SILK-FOWLS, i. 230, ii. 67, 69.
{478}
SILK-MOTH, Arrin