452 GENETICS IN RELATION TO AGRICULTURE 



There is another very important prerequisite for success in animal breed- 

 ing which comes in part from training, in part from the native ability of 

 the breeder himself, and that is the erection of a true and attainable ideal. 

 It is not necessary here to outline fully the various factors which must 

 be taken into consideration in building up an ideal, but that type when 

 it has become fixed in the breeder's mind, and his breeding can hardly 

 be systematic until his standard has been established, must be within 

 the limits of attainability of the breed with which the herdsmen is work- 

 ing, and it must also be a superior type of that breed designed to fill better 

 than any other some definite economic demand. All these are matters 

 with which genetics properly is not deeply concerned, but they make up, 

 nevertheless, a very definite portion of the subject matter which is in- 

 cluded under the term animal breeding. We see therefore that the pur- 

 pose of an account of the relation of genetics to animal breeding is de- 

 finitely circumscribed, it is to point out the significance and operation 

 of the laws of genetics in animal breeding, not however to provide a com- 

 plete compendium on this latter extensive subject. 



