EXPERIMENTS WITH ALCOHOL 155 



pedigrees of the stock used in the alcohol experiments. Of these 

 six males not represented some were used chiefly in cross-bred 

 matings and, therefore, left but few pure Barred Plymouth 

 Rock descendants: others were poor breeders and left few de- 

 scendants of any sort. 



It seems evident without further discussion that the Barred 

 Rock stock in the alcohol experiments included practically as 

 many blood lines as the general population from which it was 

 drawn and may be regarded as a representative sample of that 

 population. 



The pedigrees of the Black Hamburgs in the experiments may 

 next be considered. 



Pedigree of individuals ex mating 1896 



No. 630 O. F. S. d" 

 ^^^*^°^1^96^ ^No. 63lO.F.S.c^ 



No. K222 9 . ^,^ ^3^^ ^ j,_ g ^ 



Pedigree of individuals ex mating 1900 



(Mating 1900) 



No. 1350 O. F. S. 9 No. 630 O. F. S. & 



Pedigree of individuals ex mating 1901 

 (Mating 1901) 

 ■ No. 1352 O. F. S. 9 No. 630 O. F. S. cf 



Pedigree of individuals ex mating 1903 



(Mating 1903) 



No. 1358 O. F. S. 9 No. 630 O. F. S. c? 



It is evident from these pedigrees that we are much nearer 

 original foundation stock in the case of the Black Hamburgs 

 than with the Barred Rocks. It is important to notice in this 

 connection, however, that these 0. F. S. Hamburgs had been 

 previously bred upon the Station plant and their purity and 

 Mendelian behavior thoroughly tested before they were used to 

 breed the stock which was used in the alcohol experiments. 



