6 



GENETICS 



FIG. 2. The Scale of Success. 

 A stands for high grade; 



B, for mediocrity; 



C, for low grade. 



life but the other two may. 

 The sociologist and the 

 philanthropist are imme- 

 diately concerned with the 

 middle column; the edu- 

 cator and particularly the 

 parent with the right-hand 

 column; while the biologist 

 puts faith in the left-hand 

 column of heritage. For 

 example, a child born ACC 

 is more apt to reach the 

 top than one born CCC. In 

 selecting a mate it would be 

 far wiser to marry ACC 

 than CAA, since "blood 

 wiU tell." 



What, then, is this 

 "blood" or heritage? Ex- 

 actly what is meant by 

 heredity ? 



3. A DEFINITION OP 

 HEREDITY 



The terms heredity and 

 inheritance come to us from 

 legal practice. We "in- 

 herit" the old homestead or 

 our grandfather's clock. 

 Moreover, as "heirs to all 

 the ages" our heredity in- 



