WHAT EVOLUTION IS 85 



characters were changes in the body 

 cells — muscle, nerve, skin and so 

 forth — and that there was no known 

 mechanism whereby the changes reg- 

 istered in these cells could be trans- 

 ferred to the reproductive cells in 

 order that such changes might be 

 handed on to the offspring. If a black- 

 smith through exercise increases the 

 muscles of his arm, how are these 

 muscles to modify his reproductive 

 cells that his offspring may have larger 

 arm muscles than they otherwise would 

 have had? This theoretic objection 

 to the inheritance of acquired char- 

 acters seems to many to be an insuper- 

 able one. It is, however, an objection 

 based on ignorance and may at any 

 time be set aside by new discovery. 



Many of the older advocates of the 

 neo-Lamarckian school pointed to the 

 inheritance of mutilations as evidence 

 in favor of Lamarck's views, and it 



