1870-1882] WYVILLE THOMSON 389 



expression of extreme variation, nor on that of evolution Letter 301 

 being guided only by Natural Selection. Can Sir Wyville 

 Thomson name any one who has said that the evolution of 

 species depends only on Natural Selection ? As far as con- 

 cerns myself, I believe that no one has brought forward so 

 many observations on the effects of the use and disuse of 

 parts, as I have done in my Variation of Animals and Plants 

 under Domestication ; and these observations were made for 

 this special object. I have likewise there adduced a consider- 

 able body of facts, showing the direct action of external 

 conditions on organisms ; though no doubt since my books 

 were published much has been learnt on this head. If Sir 

 Wyville Thomson were to visit the yard of a breeder, and 

 saw all his cattle or sheep almost absolutely true — that is, 

 closely similar, he would exclaim : " Sir, I see here no extreme 

 variation ; nor can I find any support to the belief that you 

 have followed the principle of selection in the breeding of 

 your animals." From what I formerly saw of breeders, I have 

 no doubt that the man thus rebuked would have smiled and 

 said not a word. If he had afterwards told the story to other 

 breeders, I greatly fear that they would have used emphatic 

 but irreverent language about naturalists. 



The following is the passage omitted by the advice of Huxley : see his 

 Life and Letters, II., p. 14 : — 



" Perhaps it would have been wiser on my part to have 

 remained quite silent, like the breeder ; for, as Prof. Sedgwick 

 remarked many years ago, in reference to the poor old Dean 

 of York, who was never weary of inveighing against geolo- 

 gists, a man who talks about what he does not in the least 

 understand, is invulnerable." 



To G. J. Romanes. 1 Letter 302 



Down, Jan. ist, 1881. 



I send the MS., but as far as I can judge by just skimming 

 it, it will be of no use to you. It seems to bear on 

 transitional forms. I feel sure that I have other and better 

 cases, but I cannot remember where to look. 



I should have written to you in a few days on the following 



1 Part of this letter has been published in Mr. C. Barber's note on 

 " Graft-Hybrids of the Sugar-Cane," in The Sugar-Cane, Nov. 1S96. 



