IN-AND-IN BREEDING. 139 



getlier of closely -related animals in a single in- 

 stance, or at long-separated intervals, the term in- 

 and-in breeding could then be used with greater ex- 

 actness to indicate the frequent repetition of the pro- 

 cess. 



High breeding implies a careful selection of breed- 

 ing-animals within the limits of a family, with refer- 

 ence to a particular type, and regardless of relation- 

 ships. High-bred animals are not necessarily in-and- 

 in bred, although, from the system of selection prac- 

 tised, they must be closely bred to a greater or less 

 extent. 



The opponents of in-and-in breeding claim that it 

 produces a delicacy of constitution a predisposition 

 to disease, and a lack of fecundity and they often 

 fall into the error of assuming that all who do not 

 admit the truth of these claims are in favor of close 

 breeding as a rule of practice. 



For the purpose of gaining a knowledge of the 

 principles involved in the breeding together of ani- 

 mals that are closely related, we will first examine 

 the practice of those who have gained a high repu- 

 tation as breeders of domestic animals, and then 

 consider the objections to their methods of improve- 

 ment. 



From the time of Bakewell, the breeders who 

 have gained the greatest reputation have evidently 

 aimed to establish in their flocks and herds certain 

 well-marked characters that adapted the animal to a 

 particular purpose. 



In giving expression to their ideal type, or stand- 

 ard of excellence, fhey found it necessary to limit 



