30 CATTLE-BREEDING. 



butter cows will carry on the capability to the 

 third generation. 



We thus lay down the general thesis that 

 "like begets like." It is now important that 

 this proposition should be somewhat carefully 

 analyzed. First, then, it follows without more 

 proof that ordinary qualities are transmitted. 

 Some of the examples show that even tricks 

 and peculiarities of body and of mind are trans- 

 mitted. It is, however, specially important to 

 note that defects and diseases are reproduced 

 with as great persistency and frequency as 

 normal characteristics. This is a point of deep 

 importance. The medical profession fully rec- 

 ognize it, and to the breeder it becomes a source 

 of care and watchfulness. 



Medical science recognizes the inheritability 

 not merely of such diseases as consumption, 

 scrofula, and others of kindred nature, of men- 

 tal disorders such as lunacy and idiocy, of de- 

 fects such as imperfect sight and hearing, but 

 of many other obscure and faintly-developed 

 peculiarities of body, temperament, and mental 

 state. Deformities of every sort abnormal 

 growths of hair, of scaly dermal affections, 

 and many like appearances prove oftentimes 

 highly hereditable. 



Pulmonary complaints affect cattle no less 

 than man, and are found to be quite as surely 

 passed on from father to son. Other weak- 



