308 PRINCIPLES OF STOCK-BREEDING. 



heat in greater numbers, and the vigor of the ram 

 was diminished, he got a larger proportion of fe- 

 males; and toward the close, when the ewes to be 

 served were less numerous, the vigor of the ram be- 

 ing restored, the procreation of males was again in 

 excess. 



He concludes also that " the ewes that have pro- 

 duced the female lambs are, on an average, of a 

 weight superior to those that produced the males; 

 and they evidently lose more in weight than these 

 last during the suckling period ; " and that " the ewes 

 that produce males weigh less, and do not lose in 

 nursing so much as the others." l 



I am not aware of any facts to corroborate this 

 statement of M. Martegoute, which is not in accord- 

 ance with the experience of breeders generally. 



It may be that the relative age and vigor of the 

 parents has an influence, in connection with other con- 

 ditions, in determining sex ; but that the influence is 

 so marked as to be of any practical utility in breeding 

 the sexes at will remains yet to be proved. 



The uniformity in the proportion of the sexes, 

 shown by statistics, in different localities, representing 

 a great variety in the conditions of life, indicates the 

 existence of some general law that determines the sex 

 of offspring that is constant in its action. 



The proportion of males to a hundred females in 

 the different countries of Europe is reported as fol- 

 lows : 2 



1 " Principles of Breeding," by Goodale, pp. 91, 92. 



2 " Cyclopaedia of Anatomy and Physiology," vol. ii., p. 478, and 

 " Insurance Cyclopaedia," by Walford, vol. i., p. 315. 



