i6 



INHERITANCE OF COAT-PIGMENTS AND COAT-PATTERNS 



called regression. The filial average does not, with any uniformity, lag 

 behind the parental average, in the process of displacement downward in the 

 variation figure. This fact, together with the decreasing skewness of the 

 variation curve, indicates that the effects of selection in reducing the extent 



Individuals 



7O 



M.B ^^s 34.5 44.5 54.5 64.5 74,5 



FIG. 5 Effect of selection for back-stripe of increased size in hooded rats, lots A, J, K, L, and M. 



of the pigmentation will be permanent, that is, that a stable, narrow- 

 striped variety of hooded rats can be established by selection, and that 

 this variety will breed true. 



