AN ANALYSIS OF THE EFFECT OF SELECTION. 



21 



TABLE 17. Inbred Plus Lines Crossed. 



1 Does not include culture 2054, in which the mother was not-Dichaet. 



10 



11 



FIG. 10. Means and standard deviations for cross of two inbred plus lines. 

 FIG. 11. Means and standard deviations for cross of 1002 inbred plus 

 and speck (1331) minus lines. 



was nearly the same as that in FI, the F 2 -F 3 and F 3 -F 4 parent-offspring 

 correlations were not significantly different from 0, and the means of 

 the plus and minus selected series in F 3 and F 4 were practically identi- 

 cal. This constitutes practically a proof that the two lines did not 

 differ with respect to modifying genes. The result, while surprising, 

 is by no means highly improbable on the multiple-factor view. The 



