240 THE MEANING OF EVOLUTION 
that somehow there is an influence by which the 
environment produces variation. How the influences 
of the surrounding world can get down into the body 
of the parent and affect the egg is unknown. This 
is freely confessed by every biologist. All are agreed 
that Weissman’s work has made us cautious, and pre- 
vented our lightly accepting a belief in the influence 
of the environment. Yet it is felt by many that slowly 
and gradually, in the long run, the germ is affected 
in the same manner as is the body of the parent. In 
other words, even those who are not followers of 
Weissman, have accepted the idea that there is little 
inheritance of acquired characters. Yet they return 
to the belief that somehow, in some way as yet un- 
explainable, the main cause for variation in animals 
lies in the situation in which they live, and tends 
toward better adaptation to that situation. 
Whether men with this conviction are merely re- 
actionaries whose confidence is returning, or bold 
thinkers whose views will ultimately prevail, time 
alone can tell. 
A second strong objection was brought against the 
theory of Natural Selection. Darwin declared that 
small variations in favorable directions are selected 
and become the starting point of new and better 
things. It is soon seen, however, that the effect of 
unaided Natural Selection would be but to mix new 
