44 PRINCIPLES OF BREEDING. 







I chiefly attribute the varying or plastic condition of 

 the oifsi^ring. The male and female sexual elements 

 seem to be affected before that union takes place which 

 is to form a new being. But why, because the re-pro- 

 ductive system is disturbed this or that part should 

 vary more or less, we are profoundly ignorant. Nev- 

 ertheless we can here and there dimly catch a faint ray 

 of light, and we may feel sure that there must be some 

 cause for each deviation of structure however slight." 



It may be useless for us to speculate here upon the 

 laws which govern variations. The fact that these 

 exist is what the breeder has to deal with, and a most 

 important one it is, for it is this chiefly, which makes 

 hereditary transmission the problem which it is. . His 

 aim should ever be to grasp and render permanent and 

 increase so far as practicable, every variation for the bet- 

 ter, and to reject for breeding purposes such as show a 

 downward tendency. 



That this may be done, there is abundant proof in 

 the success which has in many instances attended the 

 well directed efibrts of intelligent breeders. A remark- 

 able instance is furnished in the new Mauchamp-Merino 

 sheep of Mons. Graux, which originated in a single 

 animal, a product of the law of variation, and which by 

 skillful breeding and selection has become an estab- 

 lished breed of a peculiar type and possessing valuable 



