96 DARWINISM STATED BY DARWIN HIMSELF. 



by the direct action of the surrounding conditions. I 

 was not, however, able to annul the influence of my 

 former belief, then almost universal, that each species 

 had been purposely created ; and this led to my tacit 

 assumption that every detail of structure, excepting rudi- 

 ments, was of some special, though unrecognized, service. 

 Any one with this assumption in his mind would natu- 

 rally extend too far the action of natural selection, either 

 during past or present times. Some of those who admit 

 the jftinciple of evolution, but reject natural selection, 

 seem to forget, when criticising my book, that I had the 

 above two objects in view ; hence if I have erred in giving 

 to natural selection great power, which I am very far 

 from admitting, or in having exaggerated its power, 

 which is in itself probable, I have at least, as I hope, 

 done good service in aiding to overthrow the dogma of 

 separate creations. 



IS THEKB ANT LIMIT TO WHAT SELECTION CAN EFFECT ? 



Animals and The foregoing discussion naturally leads to 

 Plants, Toi. 4]^g question, What is the limit to the possible 

 ' ° ' amount of variation in any part or quality, 

 and, consequently, is there any limit to what selection 

 can effect ? "Will a race-horse ever be reared fleeter than 

 Eclipse ? Can our prize cattle and sheep be still further 

 improved ? Will a gooseberry ever weigh more than that 

 produced by "London" in 1853 ? Will the beet-root in 

 France yield a greater percentage of sugar ? Will future 

 varieties of wheat and other grain produce heavier crops 

 than our present varieties ? These questions can not be 

 positively answered ; but it is certain that we ought to 

 be cautious in answering them by a negative. In some 

 lines of variation the limit has probably been reached. 



