GENETICS AND BREEDING 159 



junction point, at which we shall alight and change 

 cars. Just because there has been so much per- 

 fervid oratory, loose thinking, and cheap adver- 

 tising of the achievements of men and institutions 

 based on the ideal or assumed mutual interrela- 

 tionship of the science of genetics and the breeders' 

 art, it seems worth while to make a careful ob- 

 jective analysis of the actually existing relations 

 between these adjoining fields of human endeavor. 

 Such an analysis will be attempted in what follows. 

 Specifically the question to which attention is in- 

 vited is : What essential and fundamental con- 

 tributions has genetics made to the 'practice of 

 the breeders' art? Or, to put the matter in 

 another way, what particular things does the 

 most highly successful practical animal breeder 

 do now which he did not do, or performed 

 differently, before Mendelism was rediscovered 

 or Darwin wrote? 



It is generally agreed that during the past 

 fifteen years there has been a great advance in 

 our knowledge of the fundamental laws of hered- 

 ity. Indeed, it may fairly be said that more has 

 been gained in this regard within this period than 

 in the entire previous history of this field of knowl- 

 edge. The new method of investigating heredity 

 which was given by Mendel's work has for the 

 first time made a real analysis of genetic phenom- 

 ena possible. It was a truly imposing array of 

 organisms and characters which Major Hurst was 



