HEREDITY 



MM* 



O0«et 



<"iG. 40. — Diagram showing the variations in size of eight different races c 

 Paramecium. Each horizontal row represents a race derived from 

 single parent individual. The individual showing the mean size i 

 each race is indicated by a cross placed above it. The mean of th 

 entire lot is shown at X — X. The nimnbers show the measure 

 ments in microns. (After Jennings.) 



in 



