100 THE 'ORIGIN OF SPECIES.' [i860. 



from Henslow this morning, who says that Sedgwick was, on 

 last Monday night, to open a battery on me at the Cambridge 

 Philosophical Society. Anyhow, I am much honoured by 

 being attacked there, and at the Royal Society of Edinburgh. 



I do not think it worth while to contradict singes cases nor 

 is it worth while arguing against those who do not attend to 

 what I state. A moment's reflection will show you that there 

 must be (on our doctrine) large genera not varying (see p. 56 

 on the subject, in the second edition of the ' Origin '). Though 

 I do not there discuss the case in detail. 



It may be sheer bigotry for my own notions, but I prefer 

 to the Atlantis, my notion of plants and animals having mi- 

 grated from the Old to the New World, or conversely, when 

 the climate was much hotter, by approximately the line of 

 Behring's Straits. It is most important, as you say, to see 

 living forms of plants going back so far in time. I wonder 

 whether we shall ever discover the flora of the dry land of 

 the coal period, and find it not so anomalous as the swamp 

 or coal-making flora. I am working away over the blessed 

 Pigeon Manuscript ; but, from one cause or another, I get on 

 very slowly. ... 



This morning I got a letter from the Academy of Natural 

 Sciences of Philadelphia, announcing that I am elected a cor- 

 respondent. ... It shows that some Naturalists there do not 

 think me such a scientific profligate as many think me here. 



My dear Lyell, yours gratefully, 



C. Darwin. 



P.S. — What a grand fact about the extinct stag's horn 

 worked by man ! 



C. Darwin to J. D. Hooker. 



Down [May 13th, i860]. 



My dear Hooker, — I return Henslow, which I was very 

 glad to see. How good of him to defend me.* I will write 

 and thank him. 



* Against Sedgwick's attack before the Cambridge Philosophical Society. 



