IN-AND-IN BREEDING. 169 



to -her sire, but bred to a stranger in blood at the first 

 trial. She possessed great substance and constitution 

 and was a very superior animal." 



It would be difficult to find a better illustration of 

 the physiological principles that have been already 

 presented, and, as they furnish a satisfactory explana- 

 tion of all the observed facts, we cannot with reason 

 attribute them to the influence of other causes. An 

 acquaintance of Mr. Wright's says of his pigs, " They 

 are of excellent quality, readily feed, and soon attain 

 maturity." ] 



The fattening qualities of these pigs had been 

 highly developed, and finally became a dominant char- 

 acteristic, while the procreative powers were made 

 latent. 



In successfully gaining a single character, Mr. 

 Wright had neglected another essential quality that 

 was obscured for the time being. The high develop- 

 ment of the fatty diathesis would be sufficient to ac- 

 count for the lack of fecundity observed, even if there 

 was not on the start an hereditary tendency in the 

 same direction. 



That the procreative powers were not destroyed, 

 but remained latent, is shown by the fact that the sows 

 bred freely with boars of another family. 



With boars of their own blood they could not be 

 expected to breed, as the powers of fecundity, in such 

 case, would be latent in both male and female, but, 

 when they were bred with animals in which the re- 

 productive function was not latent, the defect was 

 corrected. 



1 Farmer's Magazine, vol. xxxvi., p. 388. 



