MENDEL'S LAW OF HEREDITY 



But, if now two of the cross-bred black in- 

 dividuals (Fig. 16) be mated with each other, 

 the recessive white character reappears on the 

 average in one in four of the offspring (Fig. 



FIG. 18. Diagram to explain the result shown in Fig. 17. 



17). Its reappearance in that particular pro- 

 portion of the offspring may be explained as 

 follows (see Fig. 18) : The gametes which 

 united in the original cross were, one black, 

 the other white in character. Both characters 



35 



