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 
G 
G ) 
ee 
Ss 
GO ; 
yr 
Ss 
nh 
GO 3 
| & 
ite 
ae a 
BR "5 
Bs 9, S 
og 
Be > 
Be 
“9 
FIG. I. 
G, Germ cells; S, Somatic 
cells, 
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 parent 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. 
