BY RAYMOND PEARL 



3L5 405 49t5 58.5 OS 7BJ i5 

 WDfTRREGO PRODUCTION 



108.5 LO5 



FIG. 3. Diagram showing range of variation and mean fecundity in each 

 eeneration of line D65D366. Significance of lines and cross hatching as In 

 Fig, 2, q.v. 



