IXDEX. 



of relative age of parents on, 304; in- 

 fluence of relative vigor of parents on, 

 831 ; in insects determined by nutri- 

 tion, 332 ; M. Girou's theory of, 802 ; 

 Mr. Stuyvesant's theory of, 335; M. 

 Thury's theory of, 298; Sir Everard 

 Home's theory of, 829. 



Sexes, relative proportion of, 806-315; 

 relative proportion in plural births, 

 822. 



Sexual limitation of characters, 71, 222. 



Shakespeare, Long-Horn bull, pedigree 

 of, 148, 159, 160. 



Sheath-bill, 46. 



Sheep, breeding of, twice a year, 132; 

 cases of prolific, 131; Charmoise breed, 

 origin of, 197 ; cross-bred, 191 ; in the 

 Cordilleras not prolific, 109; little- 

 eared breed of, 54; on rich pastures 

 prolific, 111; period of gestation in, 

 405; variations in, from changed con- 

 ditions, 97. 



Shepherd-dogs, inherited habits of, 41. 



Shock of nervous system of mother, in- 

 fluence of, 292. 



Short-horns, Bates's pedigrees, 144, 411 ; 

 Booth's pedigrees, 146, 147, 411 ; Col- 

 ling's pedigrees, 172 ; form of pedigree, 

 411 ; in-bred by Mr. Butts, 163 ; New 

 York Mills pedigrees, 145. 



Shropshire sheep, origin of, 192. 



Shoulders, best form of, 374. 



Sight, long and short, heredity of, 20. 



Size of animals and food-supply, 95 ; in- 

 fluence of, on fecundity, 114. 



Skin-disease, sexual limitation of, heredi- 

 fary, 222 ; skin, peculiarities of, indi- 

 cating quality, 331. 



Smell, sense of, acute in blind persons, 

 87. 



Sow, case of prolific, 132. 



Spencer, EarJ, on period of gestation, 

 403. 



Spermatozoa, several required for fecun- 

 dation, 280. 



Spontaneity, 76, 81. 



Spontaneous prepotency not probable, 

 158. 



Spooner's theory of inheritance, 237. 



Springing spaniels, changed instinct in, 

 41. 



Standard of excellence desirable, 353. 



Statistics of births, defects in, 813. 



Strain of back-tendons, 29. 



Sugar as food, relations to fertility, 



113. 

 Supernumerary organs, varied position 



of, 52. 



Surgical diseases, heredity of, 28. 

 Swelled legs, heredity, case of, 29, 30. 

 Swine, period of gestation in, 407. 



Tail, loss of, in pigs, hereditary, 56. 



Teeth, decay of, hereditary, 20, 228. 



Temperament of working-animals, 882. 



Temper of animals inherited, 18. 



Terms in use by breeders, 348. 



Texan steer. 877. 



Thorough-bred, definition of, 348. 



Toes, overlapping, heredity of, 5(3. 



Touch, indications of, 379 ; sense of, in 

 blind persons, 87. 



Trotting habit, how developed, 47. 



Tumors, bilateral symmetry of, 31. 



Turtles, successive fecundation in, 274. 



Twins, conditions favoring production of, 

 111, 126, 128 ; female not always bar- 

 ren, 128; hereditary procreation of, 

 228; inherited production of, through 

 male line, 128; production of, not an 

 indication of remarkable fertility, 186. 



U S heifer, supposed influence of imagi- 

 nation, 285. 

 Uterus, absence of, hereditary, 233. 



Value of animals, 4, 6. 



Variation from changed conditions, 105 ; 

 in animals, causes of, 93, 105; in inher- 

 ited characters, 81 ; law of, 76, 92 ; 

 greater tendency to, in domesticated 

 animals, 92; in abnormal characters, 

 52 ; not spontaneous, 76. 



Variations that are desirable difficult to 

 retain, 156; from endemic causes, 106; 

 tendency to, undesirable, 890. 



Voice, organ of, in the ass and mule, 248, 

 247. 



Walker's theory of inheritance, 235, 241, 



250-253. 



Walk, peculiarity in, hereditary, 20. 

 Wealth, relations of, to fertility, 123. 

 Wheat, climatic variations in, 94. 



