326 PRINCIPLES OF STOCK-BREEDING. 



From the frequency of the cases in which there is 

 a greater number of one sex than of the other, in the 

 produce of particular females, it has been assumed 

 that the female parent had a greater influence in de- 

 termining sex than the male. 



There are, however, several reasons why such a 

 generalization should not be accepted as the expres- 

 sion of a general law. Among domestic animals, al- 

 though the male practically constitutes one-half of 

 the breeding-stock of a flock or herd, the females are 

 by far the most numerous ; and it would follow from 

 this superiority of numbers that the instances of sex 

 determined by females would be observed in greater 

 numbers than the instances of sex determined by 

 males, if the power of influencing sex were the same 

 in both males and females. 



Moreover, as the male is usually coupled with a 

 number of females, any influence he might have in 

 determining the sex of his offspring would not be so 

 readily noticed as a similar influence on the part of 

 the female. Again, if a particular male has a decided 

 tendency to produce offspring of one sex, it is prob- 

 able that among the many females with which he is 

 coupled there might be found a number that have a 

 tendency to produce offspring of the same sex. 



The sex of the offspring of these females would, 

 therefore, be determined by the combined influence 

 of both parents acting in the same direction. 



The statistics of such cases, unless great care is taken 

 to obtain all the facts bearing upon them, might be 

 readily interpreted as evidence that the female parent 

 had the greatest influence upon the sex of the offspring. 



