ME. Q. J. EOMANES ON PHYSIOLOOICAL SELECTION. 337 



Physiological Selection ; an Additional Suggestion on the 



Origin of Species. 



By Geor&e J. EoMANEs, M.A., LL.D., F.E.S., F.L.S. 



[Eead 6th May, 1886.] 



Inteodfction. 



Theee can be no one to whom I yield in my veneration for the 

 late Mr. Darwin, or in my appreciation of his work. But for 

 this very reason I feel that in now venturing to adopt in some 

 measure an attitude of criticism towards that work, a few words 

 are needed to show that I have not done so hastily, or without 

 due premeditation. 



It is now fifteen years since I became a close student of Dar- 

 winism, and during the greater part of that time I have had the 

 privilege of discussing the whole philosophy of Evolution with 

 Mr. Darwin himself. In the result I have found it impossible to 

 entertain a doubt, either upon Evolution as a fact, or upon 

 Natural Selection as a method. But during all these years it has 

 seemed to me that there are certain weak points in the other- 

 wise unassailable defences with which Mr. Darwin has fortified 

 his citadel, or in the evidences with which he has surrounded his 

 theory of natural selection. And the more I have thought upon 

 these points, the greater has seemed the difficulty which they 

 present ; until at last I became satisfied that some cause, or 

 causes, must have been at work in the production of species 

 other than that of natural selection, and yet of an equally general 

 kind. 



While drifting into this position of scepticism with regard to 

 natural selection as in itself a full explanation of the origin of 

 species, it was to me a satisfaction to find that other evolutionists, 

 including Mr. Darwin himself, were travelling the same way."" 

 And since Mr. Darwin's death the tide of opinion continues to 

 flow in this direction ; so that at the present time it would be 

 impossible to find any working naturalist who supposes that sur- 

 vival of the fittest is competent to explain all the phenomena of 

 species-formation ; while on the side of general reasoning we need 

 not go further than the current issue of the ' Nineteenth Century ' 

 to meet with a systematic statement of this view by the highest 

 living authority upon the philosophy of evolution. There- 



LINN. JOTJEN. — ZOOLOGY, VOL. XIX. 27 



