ASA GRAY. 115 



Elsewhere Darwin suggested that the pouter pigeon, 

 if it occurred wild, and used its inflated crop as a 

 float, would be considered as a striking example ot 

 design. 



This controversy between them continued *for 

 many years. We find Asa Gray referring to the 

 argument of the pigeons three years later. Thus he 

 wrote (September 1st, 1863) : — 



"I will consider about fantastic variation of pigeons. I 

 see afar trouble enough ahead quoad design in nature, but 

 have managed to keep off the chilliness by giving the knotty- 

 questions a rather wide berth. If I rather avoid, I cannot 

 ignore the difficulties ahead. But if I adopt your view boldly, 

 can you promise me any less difficulties ? " 



Writing the concluding paragraphs of the " Varia- 

 tions of Animals and Plants under Domestication," 

 Darwin evidently bore in mind his controversies on 

 the subject with Asa Gray and Lyell, and the attacks 

 of the Duke of Argyll and others. Sending advanced 

 sheets to Asa Gray, he wrote on October 16 th, 

 1867 :— 



"I finish my book with a semi-theological paragraph, in 

 which I quote and differ from you ; what you will think of it, 

 I know not." 



In relation to this interesting controversy, I think 

 it well to quote, almost in full, the metaphor by 

 which Darwin enforced his argument that the origin 

 of species by natural selection precluded a belief in 

 design in nature as it was ordinarily conceived at the 

 time. 



