74 THE THEORY OF NATURAL SELECTION 



result of so many offshoots which come to an end at 



the death of the organism * and leave no progeny of 



their own. 



Wilson has expressed this view of Weismann's very 



clearly : * It is a reversal of the true point of view to 

 regard inheritance as taking place 

 from the body of the parent to that 

 of the child. The child inherits 

 from the parent germ-cell, not from 

 the patent body, and the germ-cell 

 owes its characteristics not to the 

 body which bears it but to its 

 descent from a pre-existing germ- 

 cell of the same kind. Thus the 

 body is as it were an offshoot from 

 the germ-cell. As far as inheri- 

 tance is concerned the body is 

 merely the carrier of the germ-cells 

 which are held in trust for coming 

 generations.' (The diagram illus- 

 trating Weismann's theory of in- 

 heritance is a modification of that 

 given by Wilson.*) 



In the light of this conception 

 it may be seen that the idea of the 

 inheritance of a modification ac- 

 quired by an adult bodily organ 



is comparable with the supposition that if a man 



develops his muscles by exercise his brother's children 



will be thereby modified. 



* ' The Cell in Development and Inheritance,' p. 13. 



FIG. i. 



G, Germ cells ; S, Somatic 

 cells. 



