i860.] schaaffhausen. 319 



I do not quite understand what you mean by saying, " that 

 the more they prove that you underrate physical conditions, 

 the better for you, as Geology comes in to your aid." 



... I see in Murray and many others one incessant fallacy, 

 when alluding to slight differences of physical conditions as 

 being very important ; namely, oblivion of the fact that all 

 species, except very local ones, range over a considerable 

 area, and though exposed to what the world calls considerable 

 diversities, yet keep constant. I have just alluded to this in 

 the ' Origin ' in comparing the productions of the Old and 

 the New Worlds. Farewell, shall you be at Oxford ? If H. 

 gets quite well, perhaps I shall go there. 



Yours affectionately, 



C. Darwin. 



C. Darwin to C. Lyell. 



Down [June 14th, i860]. 



. . . Lowell's review * is pleasantly written, but it is clear that 

 he is not a naturalist. He quite overlooks the importance of 

 the accumulation of mere individual differences, and which, I 

 think I can show, is the great agency of change under 

 domestication. I have not finished Schaaffhausen, as I read 

 German so badly. I have ordered a copy for myself, and 

 should like to keep yours till my own arrives, but will return 

 it to you instantly if wanted. He admits statements rather 

 rashly, as I dare say I do. I see only one sentence as yet at 

 all approaching natural selection. 



There is a notice of me in the penultimate number of ' All 

 the Year Round,' but not worth consulting ; chiefly a well- 

 done hash of my own words. Your last note was very 

 interesting and consolatory to me. 



I have expressly stated that I believe physical conditions 

 have a more direct effect on plants than on animals. But the 



V 



* J. A. Lowell in the 'Christian Examiner,' May iS6o. 



