20 



PHYSICAL BASIS OF HEREDITY 



Tall 



@@ 



Sfiott \s\ \s\ 



Fig. 1. — Cross between a tall and a short race of garden peas. The F\ generation is 

 tall. In the second generation, Fi, there are three talis to one short. {P\, F\ and F2 were 

 reared from peas supplied by Dr. O. E. White.) 



