( Ixvi ) 



arisen of late years appear to me to turn rather upon the 

 degree of efficiency which can he assigned to the process. 



It is not my intention to enter now into the question as 

 to what Mr. Darwin meant hy this or that passage in his 

 writings ; neither am I about to take upon myself the respon- 

 sibility of claiming to be among his infallible interpreters. I 

 am simply a disciple of nearly a quarter of a century's stand- 

 ing of the doctrine formulated by him and by Wallace. If, 

 with the progress of discovery and the advancement of know- 

 ledge, new considerations have arisen in the course of time 

 which are not to be found within the two covers of the 

 " Origin of Species," or any other of Mr. Darwin's books, 

 then, from what I knew of Mr. Darwin himself, I am bound 

 to say that it is doing an injustice to the scientific spirit of 

 our great leader if we allow that the acceptance of any exten- 

 sion or completion of his work justifies our being branded 

 Avith a denominational epithet, as though we had founded a 

 new sect.* We either accept the theory as Darwin left it, 

 after making use of all the knowledge available at his time 

 viz., that natural selection is the main but not the exclusive 

 means of the modification of species, or we may, following 

 Weismann and Wallace, reject the factor of use-inheritance, 

 and so give more weight to natural selection as a prime factor. 

 The only really important modification of the theory since 

 Darwin's time, is this elimination of the remnant of Lamarck- 



you. No doubt there wi 1 be much error found in my book, but I have jrreat 

 confidence that the main view will be, in time, t'juud correct ; for I find, 

 without exception, that those naturalists who went at first one incli with me 

 now go a foot or yard with me. 



"This note obviously requires no answer. 



" Pr.iy believe me, 



" Ywurs sincerely, 



" C. Uarwix." 



My friend, Mr. Francis D.vrwin, wh ) has sanctioned the publication of this 

 letter, iuforms ma that it must have been written in 1860. 



* I have in ray mind, among many similar instances of Darwin's scientific 

 candour, tlie readiness with which he accepted Fleeming Jenkin's criticism 

 as to the improbability of single varieties gaining a footing, owing to the 

 "swamping effects" of intercrossing. This point is well brought out m 

 Poulton's recent work on " Charles Darwin and the Theory of Natural 

 Selection " (p. 81 ; also the " Life and Letters," Vol. 111., p. 107). 



