DARWIN AND MUTATION 255 



(4) 1860. ' About sudden jumps : I have no objection to 

 them — they would aid me in some"cases. All I can say is, 

 that I went into the subject, and found no evidence to make 

 me believe in jumps ; and a good deal pointing in the other 

 direction.' ' 



(5) 1871. ' . . . I have now almost finished a new edition 

 of the Origin, which Victor Carus is translating. There is 

 not much new in it, except one chapter in which I have 

 answered, I hope satisfactorily, Mr. Mivart's supposed diffi- 

 culty on the incipient development of useful structures. I 

 have also given my reasons for quite disbelieving in great 

 and sudden modifications.' ^ 



(6) 1873. ' It is very difficult or impossible to define 

 what is meant by a large variation. Such graduate into 

 monstrosities or generally injurious variations. I do not 

 myself believe that these are often or ever taken advantage 

 of under nature. It is a common occurrence that abrupt 

 and considerable variations are transmitted in an unaltered 

 state, or not at all transmitted, to the offspring, or to some 

 of them. So it is with tailless or hornless animals, and 

 with sudden and great changes of colour in flowers.' ' 



(7) 1880. 'It is impossible to urge too often that the 

 selection from a single varying individual or of a single 

 varying organ will not suffice.' * 



(8) 1880. Finally the letter to Nature, dated 



November 5, 1880, was one of the strongest 



things ever written by Darwin. It originally 



contained a passage which the writer omitted 



on the advice of his most combative friend 



Huxley. The two grounds on which Darwin 



based his emphatic protest are stated in the 



following passage. A mutationist conception of 



evolution based on ' extreme variation ' is the 



» To W. H. Harvey, August, I860.— Jfore Letters, i. 166. 

 ' To E. Hackel, December 27, ISn.—More Letters, i. 335. 

 ' To R. Meldola, August 13, 1873.— Motv Letters, i. 350. 

 * To A. R. Wallace, January 5, 1880.~More Letters, i. 384. 



