APPENDIX A. 



Mr. Gulick's Criticism of Mr. Wallace's Views on 

 Physiological Selection. 



I HAVE received from Mr. Gulick the results of his 

 consideration of Mr. Wallace's criticism. As these results 

 closely resemble those which I have myself reached, and 

 as they were independently worked out on the other side of 

 the globe, I deem it desirable to publish them here for the 

 sake of comparison. 



In his covering letter Mr. Gulick writes : — 



Mr. Wallace has most certainly adopted the fundamental prin- 

 ciples of our theory, and in an arbitrary way attempted to claim 

 the results produced by these principles as the effects of natural 

 selection. He takes our principles, which in the previous 

 chapter he has combated ; but he makes such disjointed use of 

 them that I am not willing to recognize his statement as an 

 intelligible exposition of our theory. ... I have endeavoured to 

 indicate at what points Mr. Wallace has deserted his own prin- 

 ciples, and at what points he has failed to make the best use of 

 ours. To bring out these points distinctly has been no easy 

 task ; but if you regard this paper on The Preservation and Ac- 

 cumulation of Cross-infertility as giving any help in elucidating 

 the true principles, and in showing Mr. Wallace's position in 

 regard to them, I shall be satisfied. Please make any use of it 

 that may seem desirable, and then forward it to Professor 

 Dana. 



