Analysis of Heterogeneity in Complex Chaeacteks 



257 



From Fg to F^o the same method of mating and selection of parents was followed, 

 giving a race of constantly decreasing variability, and, as far as amount of 

 pigment was concerned, much above that of the normal parent strain. In F^ 

 there appeared 1 male entirely black above on the pronotum, but not on the 

 sides. This individual was separated and tested separately. 



Fio 



F9 



^ m m 



IP ^ ^ 



m ^ <^ 



m m m^ 



F8- 



F7- 



F6 



Tf,- 



F4 



F3 



.F2 



Fi 



< , . <— , , 



^m ^ ^ ^ ^ ^ 



^ m m 



m ^ m w^ 



^ m 



FiQ. 42. — Diagrammatic representation of the effort to modify through accumu- 

 lative selection the amount of pigment in a pure extracted biotype 4 stock of 

 L. multitceniata. The figure shows graphically the Ineffectiveness of quantitative 

 selection in permanently altering the type of this race. 



In Fg two matings were made; one (A) continued the intensely selected strain 

 through to Fjo; the other (B) was a random mating from all classes and was 

 allowed to inbreed freely. Figure 42 shows, without further comment, the 

 result. The selected race was kept up to the standard, the nonselected at once 

 began to move backwards and soon showed only the normal biotype 4 pattern. 



