THE HORSE BREEDING. 685 



It is one of the many mysteries of generation, which has wisely 

 been concealed from man. 



It was at earliest date assumed that the male had two tes- 

 ticles, and the female two ovaries, and that somehow the two 

 sexes had a relation to these dual organisms. It was next as- 

 sumed that the right testicle and the right ovary were the pro- 

 ducers of males, and the female came from the left testicle and 

 left ovary. Physiologists and farmers long since proved the 

 folly of these assumptions. Men and lower animals having but 

 one testicle, and women and female animals with but one ovary 

 have produced young of both sexes, and with the same regu- 

 larity, as to sex, as when possessed of both organisms 

 complete. 



The Country Gentleman, some years ago, published the 

 theory of Professor Thury, of Geneva, claiming that " the 

 sex depends upon the degree of maturity of the egg at the 

 moment of fecundation," the less mature producing a female; 

 the more mature, a male. 



In accordance with this theory, the belief is common among 

 breeders that a female animal, served by the male during the 

 first half of the period of heat, would give a female or a ma- 

 jority of females; and served later in the heat, would produce 

 a male, or a majority of males. This has been proven a failure, 

 after a long line of years of close observation. 



There is an important physiological fact overlooked in this 

 theory. It is this : Fecundation is the result of the ovum of 

 of the female coming into contact with the spermatozoa of the 

 male. Now, as this union or contact does not necessarily oc- 

 cur at time of copulation, the theory must fail as often as this 

 union fails. Dalton's Physiology has shown that the period 

 when the ovum escapes from the ovary is uncertain. Caste has 

 shown that it may escape early or late in the period of heat. 

 In experiments with dogs and rabbits, it is shown that several 

 days may elapse after copulation before the ovum comes in con- 

 tact with the spermatozoa, if at all. 



Naturalists are now investigating the plausible theory that 

 sex is determined by the activity of the processes of nutrition. 



