20 PRINCIPLES OF BREEDING. 



ten years old, as at two ; meantime he has got, per- 

 haps, five hundred calves, which in due time become 

 worth ten or twenty dollars each more than those from 

 the other. Which now seems the wiser purchase ? 

 Was the higher estimate placed on the well bred ani- 

 mal based upon fancy or upon intrinsic value ? 



The conviction that a better knowledge of the prin- 

 ciples of breeding would render our system of agricul- 

 ture more profitable, and the hope of contributing 

 somewhat to this end, have induced the attempt to set 

 forth some of the physiological principles involved in 

 the reproduction of domestic animals, or in other 

 words, the laws which govern hereditary transmission. 



