104 PRINCIPLES OF STOCK-BREEDING. 



merit of peculiarities that are in themselves objection- 

 able. 



From the manner in which family characters are 

 produced, it will be exceedingly difficult to ingraft 

 any new character upon a family without destroying, 

 to a greater or less extent, its specific characteristics. 

 In the improved breeds, and especially in those in 

 which early maturity and the tendency to lay on fat 

 are highly developed by artificial treatment, the great 

 predominance of one group of characters seems to in^ 

 volve an unstable condition of the organization, and a 

 consequent tendency to further variation. 



It is often remarked that it is more difficult to re- 

 tain a given character than to produce it. If the con- 

 ditions that gave rise to a particular character are 

 changed, the character itself must be changed also. 

 It is a common mistake of those not familiar with the 

 principles of breeding and the causes of variation, to 

 suppose that the highly-artificial characters of im- 

 proved breeds can be retained in the absence of the 

 conditions that produced them. 



If high feeding has developed a variation in a par- 

 ticular direction, a scanty supply of food would cer- 

 tainly destroy it, and produce a variation of an oppo- 

 site character. Improved characters can only be made 

 permanent by breeding together the animals that pos- 

 sess them, and continuing without variation the same 

 system of management that originally produced them. 



Improvements that have been effected by better 

 care and an abundant supply of food for many genera- - 

 tions, may be lost in a comparatively short time, by 

 placing the animals under less favorable conditions 



