230 THE BREEDING OF ANIMALS 



ments with swine were unfavorable to the practice of 

 in-breeding. According to Cornevin, among pigeons it 

 is the rule for brother and sister to mate. The same 

 is also generally true of ducks, geese, guinea fowls 

 and swans. After eleven years of in-breeding pigeons 

 and geese, he was unable to observe any changes in 

 color, weight or fecundity which could be ascribed to 

 in-breeding. 



Georg Wilsdorf, 1 the German authority, has found 

 by investigation that most pure breeds have resulted 

 from in-breeding. He says, " In our studies of the his- 

 tory of various breeds, we next made the astonishing 

 discovery that the best living individuals belonged to 

 families which, when their pedigrees were traced, were 

 found all to come from a single family often from a 

 single individual. By way of illustration I might cite 

 the Hanoverian halfbloods, which we know particularly 

 through the studies of de Chapeaurouge and Grabensee 

 to have come almost altogether from three stallions, of 

 which Norfolk has hitherto had the greatest influence on 

 the breed an influence that is increasing all the time. 

 Researches into the swine breeding of the Visselhovede 

 district, and into that of Hildesheim in Bavaria, have 

 shown that in each case a single boar was the ancestor 

 of various valuable families, to-day widely scattered. 

 And Hoesch of Neukirchen has found that his valuable 

 strain of swine is principally due to the blood of a single 

 early boar Richard." 



" The modern science of breeding, however, stands 

 firm in its belief that for the production of definite types 

 for special purposes in-breeding is the quickest and most 

 certain method of procedure, and all great breeders who 



1 Journal of Heredity, March, 1915, pp. 110-111. 



