i86o.] LYELL'S CRITICISMS. 339 



July, August, and October, which were reprinted as a pam- 

 phlet in 1861, and now form chapter iii. in ' Darwiniana' (1876), 

 with the heading 'Natural Selection not inconsistent with 

 Natural Theology.'] 



C. Darwin to C. Lyell. 



Down, September i2th [1860], 



MY DEAR LYELL, I never thought of showing your letter 

 to any one. I mentioned in a letter to Hooker that I had 

 been much interested by a letter of yours with original objec- 

 tions, founded chiefly on Natural Selection not having done 



so much as might have been expected In your letter 



just received, you have improved your case versus Natural 

 Selection ; and it would tell with the public (do not be 

 tempted by its novelty to make it too strong) ; yet it seems 

 to me, not really very killing, though I cannot answer your 

 case, especially, why Rodents have not become highly de- 

 veloped in Australia. You must assume that they have 

 inhabited Australia for a very long period, and this may or 

 may not be the case. But I feel that our ignorance is so 

 profound, why one form is preserved with nearly the same 

 structure, or advances in- organisation or even retrogrades, or 

 becomes extinct, that I cannot put very great weight on the 

 difficulty. Then, as you say often in your letter, we know 

 not how many geological ages it may have taken to make any 

 great advance in organisation. Remember monkeys in the 

 Eocene formations : but I admit that you have made out an 

 excellent objection and difficulty, and I can give only un- 

 satisfactory and quite vague answers, such as you have 

 yourself put ; however, you hardly put weight enough on 

 the absolute necessity of variations first arising in the right 

 direction, videlicet, of seals beginning to feed on the shore. 



I entirely agree with what you say about only one species 

 of many becoming modified. I remember this struck me 



z 2 



