390 GROWTH OF THE 'ORIGIN.' [1844 



lability of species ; that facts can be viewed and grouped 

 under the notion of allied species having descended from 

 common stocks. With respect to books on this subject, I 

 do not know of any systematical ones, except Lamarck's, 

 which is veritable rubbish ; but there are plenty, as Lyell, 

 Pritchard, &c., on the view of the immutability. Agassiz 

 lately has brought the strongest argument in favour of immu- 

 tability. Isidore G. St. Hilaire has written some good Essays, 

 tending towards the mutability-side, in the ' Suites a Buffon,' 

 entitled " Zoolog. Generate. " Is it not strange that the author, 

 of such a book as the * Animaux sans Vertebres,' should have 

 written that insects, which never see their eggs, should will 

 (and plants, their seeds) to be of particular forms, so as to 

 become attached to particular objects. The other, common 

 (specially Germanic) notion is hardly less absurd, viz. that 

 climate, food, &c., should make a Pediculus formed to climb 

 hair, or wood-pecker, to climb trees. I believe all these 

 absurd views arise, from no one having, as far as I know, 

 approached the subject on the side of variation under domes- 

 tication, and having studied all that is known about domesti- 

 cation. I was very glad to hear your criticism on island-floras 

 and on non-diffusion of plants : the subject is too long for a 

 letter : I could defend myself to some considerable extent, 

 but I doubt whether successfully in your eyes, or indeed in 

 my own. . . . 



C. Darwin to J. D. Hooker. 



Down [July, 1844]. 



... I am now reading a wonderful book for facts on 

 variation Bronn, ' Geschichte der Natur.' It is stiff German : 

 it forestalls me, sometimes I think delightfully, and some- 

 times cruelly. You will be ten times hereafter more horrified 

 at me than at H. Watson. I hate arguments from results, 

 but on my views of descent, really Natural History becomes 

 a sublimely grand result-giving subject (now you may quiz 

 me for so foolish an escape of mouth). ... I must leave this 



