HUMAN HEREDITY. 359 



HUMAN HEREDITY. 



Br JAMES H. STOLLER, 



PROFESSOR OF NATURAL HISTORY IN UNION COLLEGE. 



IN common speech we use the term heredity as signifying simply 

 that principle by which the qualities of parents are transmitted 

 to their children. We give the term a meaning broad enough to 

 covei facts which come within our ordinary notice. We see that 

 the features of children — the shape of the brow and nose, the color 

 of the hair and eyes — bear a resemblance to those of the parents ; 

 as they grow older we notice not only physical but also psychical 

 resemblances — the temperament, tastes, and aptitudes are more or 

 less like those of the parents. We find an explanation of these 

 likenesses in the principle of heredity ; and, as no evidence of any 

 deeper operation of such a principle comes within our ordinary 

 observation, we limit it to these particulars. It is true that occa- 

 sionally we are reminded that the principle may extend to a 

 second generation ; we see the traits of the grandparent reap- 

 pearing in the child, this being most noticeably true in respect 

 to certain bodily disorders, as scrofulous diseases and certain 

 forms of insanity. But we seldom think that the principle of 

 heredity operates through more than the two or three generations 

 of our immediate ancestors, or that any other qualities than those 

 which are specifically peculiar to us — that mark our individuality 

 of body or mind — come to us by it. 



A little reflection, however, must convince us that this prin- 

 ciple works more deeply. Those qualities that distinguish us as 

 members of a nationality — whence come they ? As Americans 

 we pride ourselves that there is something distinctive about us, 

 that places us in a different category from Englishmen and 

 Frenchmen. Whence come these national characteristics ? They 

 were possessed by our fathers and our grandfathers, and the im- 

 mediate inference, therefore, is that they come to us by inheritance. 

 Of course, we have to consider that the fathers who were the 

 founders of the nation did not inherit the American character- 

 istics, since we must regard them as the original possessors of 

 them. The fact seems to be that national characteristics origi- 

 nate in external causes, but once established they are perpetuated 

 by inheritance. It may be urged, of course, that external causes 

 operate upon succeeding generations as well as the antecedent 

 one, as evidenced in our nationality by its rapid absorption of 

 foreign stock. No doubt the direct influence of our institutions 

 is a constant force in the development of the national character- 

 istics, and goes a great way toward Americanizing citizens of for- 

 eign birth even in a single generation. But to native-born Ameri- 



