HAECKEL, JAGER, DARWIN. 2/5 



this, the only principle left upon which Weisman 

 can explain the modification is selection. Having 

 banished inheritance from parent to child, the accu- 

 mulation of variations must be by the selection of 

 such chance varieties as appear in the ovum. Even 

 though it be claimed that the ovum is particularly 

 subject to variation, it is plain that all of the objec- 

 tions urged against natural selection return with re- 

 doubled force. When in addition we remember 

 that there is in some cases positive evidence of the 

 inherited effects of use and disuse, it is evident that 

 this theory of Weismann must be somewhat modi- 

 fied before it can be accepted. It only adds diffi- 

 culties to the problem without removing them. 

 While it may be that Weismann has found the ex- 

 planation of heredity, he has failed to find the ex- 

 planation of variation. 



Haeckel, yager, Darwin. 



A number of other explanations of this funda- 

 mental fact we pass over with a word, since they 

 only profess to be explanations of heredity, without 

 materially assisting toward the solution of the 

 problem which we are considering the modifica- 

 tion of species. Haeckel has a theory which he 

 calls perigenesis, but it is little more than one of 

 words. He thinks that the individual atoms of the 

 body remember. The essence of his theory is that 

 heredity is an unconscious memory, the various 

 parts of the body remembering the corresponding 

 parts of the ancestor. This, with the suggestion that 

 reproduction is the transference of a wave motion 



