ch. x.] 1843-1858. 193 



C. D. to A. R. Wallace. Moor Park, May 1st, 1857. - 



My dear Sir I am much obliged for your letter of 

 October 10th, from Celebes, received a few days ago ; in a 

 laborious undertaking, sympathy is a valuable and real en- 

 couragement. By your letter and even still more by your 

 paper* in the Annals, a year or more ago, I can plainly see 

 that we have thought much alike and to a certain extent 

 have come to similar conclusions. In regard to the Paper 

 in the Annals, I agree to the truth of almost every word of 

 your paper; and I dare say that you w r ill agree with me that 

 it is very rare to find oneself agreeing pretty closely with 

 any theoretical paper ; for it is lamentable how each man 

 draws his own different conclusions from the very same facts. 

 This summer will make the 20th year (!) since I opened my 

 first note-book, on the question how and in what way do 

 species and varieties differ from each other. I am now pre- 

 paring my work for publication, but I find the subject so 

 very large, that though I have written many chapters, I do 

 not suppose I shall go to press for two years. I have never 

 heard how long you intend staying in the Malay Archipela- 

 go ; I wish I might profit by the publication of your Travels 

 there before my work appears, for no doubt you will reap a 

 large harvest of facts. I have acted already in accordance 

 with your advice of keeping domestic varieties, and those 

 appearing in a state of nature, distinct ; but I have some- 

 times doubted of the wisdom of this, and therefore I am 

 glad to be backed by your opinion. I must confess, how- 

 ever, I rather doubt the truth of the now very prevalent 

 doctrine of all our domestic animals having descended from 

 several wild stocks ; though I do not doubt that it is so in 

 some cases. I think there is rather better evidence on the 

 sterility of hybrid animals than you seem to admit ; and in 

 regard to plants the collection of carefully recorded facts 

 by Kolreuter and Gaertner (and Herbert) is enormous. I 

 most entirely agree with you on the little effects of " cli- 

 matal conditions," which one sees referred to ad nauseam 

 in all books : I suppose some very little effect must be at- 

 tributed to such influences, but I fully believe that they are 

 very slight. It is really impossible to explain my views (in 



* " On the Law that has regulafed the Introduction of New Species." 

 Ann. Nat. Hist., 1855. 



