NEO-LAMARCKIANISM. 267 



stantly in motion. Low plants move freely from 

 place to place. The visitation of insects produces 

 indirectly a certain amount of motion which has its 

 influence. Even in plants, therefore, the activities of 

 the individual may be the important origin of varia- 

 tion. 



This whole theory is very simple and logical. But 

 there is one point which must be more definitely 

 proved before use can be accepted as having the far- 

 reaching influence here supposed. It must be more 

 surely demonstrated that animals do inherit the 

 effects of use and disuse. That use does increase 

 the size of organs in the individual using them can 

 not be questioned ; but it is by no means so certain 

 that this effect is transmitted to the next generation. 

 The blacksmith develops a large arm, but the arms 

 of his children are no larger than those of other 

 children. It is indeed very seldom that any direct 

 evidence can be obtained of the inheritance of 

 acquired variations of this character. Darwin, with 

 the vast amount of evidence at his command, was 

 inclined to think that they were not, as a rule, trans- 

 mitted, and that, therefore, this principle was of 

 little importance. He has given some instances, 

 however, which he ascribes to the effect of use or 

 disuse. Rudimentary organs, for instance, can be 

 explained in no other way. But the direct evidence 

 of observation would hardly be expected, even if 

 the theory were true, since the effects of inherited 

 use would be so difficult to distinguish from those 

 of actual use. In order that a blacksmith's children 

 should show any marked difference, it would be 



