( cvi ) 



when no longer sustained by selection. If, then, mutual 

 fertility be the result of unceasing selection, and mutual 

 sterility the inevitable, even if long-postponed, consequence 

 of its cessation, it is obvious that Huxley's difficulty is solved, 

 while his suggested experimental creation of sterility by 

 selection would not reproduce any natural operation : it would 

 afford a picture of a natural result but would be produced 

 in an unnatural way. This criticism of Huxley's contention 

 was advanced by the present writer three years ago,* the 

 final conclusion being stated in the paragraph printed 

 below : — 



" If, then, we cannot as yet reproduce by artificial selection 

 all the characteristics of natural species-formation, but can 

 only imitate natural race-formation, we can nevertheless 

 appreciate the reasons for this want of success, and are no 

 more compelled to relinquish our full confidence in natural 

 selection than we are compelled to adopt a guarded attitude 

 towards evolution because our historical records are not 

 long enough to register the change of one species into 

 another," t 



It was therefore with intense interest and pleasure that I 

 read the following sentences in a letter written by Darwin to 

 Huxley, Dec. 28, [1862] — sentences which show that criticism 

 practically identical had been made by the illustrious naturalist 

 nearly forty years earlier. 



"We differ so much that it is no use arguing. To get the 

 degree of sterility you expect in recently formed varieties 

 seems to me simply hopeless. It seems to me almost like 

 those naturalists who declare they will never believe that one 

 species turns into another till they see every stage in 

 progress." J 



After reading, in tlie first volume of "More Letters," the 



often-repeated refutation of Huxley's objection so clearly and 



strongly expressed in letters received by the objector himself, 



it is surprising that no effect was produced, and that reference 



should have been nearly always made to this supposed fiaw in 



the theory of natural selection, whenever the great compara- 



* "The Quarterly Review," No. 3S5, Januaiv 1901, pp. 368-371. 



+ /. c. p. 371. 



X "More Letters," vol. i, p. 225, Letter 154. 



