THE AMERICAN NATURALIST LVol. LV 



TABLE XI 



[NOCULATION TO DeAT] 



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ing on vigor in other respects. In the present case, how- 

 ever, the difference does not appear very striking. In 

 particular, the superiority of the control stock B over 

 the inbreds seems very dubious. An earlier test of this 

 question was made by Mr. E. H. Riley and Dr. E. C. 

 Schroeder, of the Bureau of Animal Industry, when the 

 inbred stock was in the sixth and seventh generations of 

 inbreeding. They found that the inbred was distinctly 

 inferior to the control stock in resistance. At that time, 

 however, eighteen families were on hand. It is not un- 

 likely that the four families tested in the present experi 

 ment are a selected lot in respect to resistance. 



