MATIXG AND SELECTION. 139 



would be possible, and the unnatural mating would only tend to 

 increase the strength of the already present good qualities. 

 "While this would be an impossibility as applied to the human 

 family on account of the promiscuous intermingling and indelible 

 stamping of inherent defects for generations and generations, 

 when applied to animals its rationality becomes apparent. 

 Where due attention has been paid to the breeding only from 

 healthy, well formed subjects, in time the disposition for health 

 and form become inherent, and as a sound constitution and per- 

 fect conformation are essential to successful breedins, it is the 

 development of these points which we most desire. For this 

 reason the objection to breeding from close relationship, which is 

 insurmountable in the human family, is untenable when applied 

 to animals. The advantages of in-breeding as applied to animtds 

 are as follows : Siipposing that the qualities of both parents are 

 good, the more likelihood of the progeny inheriting them by 

 breeding with a view to improvement, the best qualities become 

 concentrated in one family. Should the members of this family 

 not breed one with the other, they would most likely have to 

 be crossed with inferior animals of either sex. This process in- 

 stead of furthering would retard improvement. It is for this 

 reason, therefore, that the most eminent and successful breeders 

 have built up and perpetuated individual families of sheep by 

 the process of in-breeding, and the stock from these pm-e-bred 

 sheep have proved the strength of heredity by the inheritance of 

 the good qualities of their in-bred ancestors. 



Where in-breeding fails is in neglect of proper selection, 

 not culling the weak and badly formed from the flock, the 

 breeding of these only tending to perpetuate defects, or whore 

 two animals possessing the same bad quality are allowed to 

 breed. N^otwithstanding their own good qualities, the tendency 

 to perpetuate the bad becomes increased twofold and is hard to 

 get rid of, a defect seemingly being handed down with greater 



