lbs THE GEXESIS OF SPECIES. [Chap. III. 



in regard to wliicli some additional remarks will be found 

 towards the end of the seventh chapter. 



In tliis third cliapter an effort has been made to sliow 

 that while on the Darwinian theory concordant \'ariations 

 are extremely improbable, yet Xature presents us with 

 abundant examples of such ; the most striking of which 

 are, perhaps, the higher organs of sense. Also that an im- 

 portant intluence is exercised by conditions connected with 

 geographical distribution, but that a deeper-seated influence 

 is at work, wdiich is hinted at by those special tendencies 

 in definite directions, which are the pro])erties of certain 

 groups. Finally, that these facts, when taken together, 

 afford stroni!' evidence that "Xatural Selection" has not 

 been the exclusive or predominant cause of the various 

 organic structural peculiarities. This conclusion has also 

 been re-enforced by the consideration of phenomena pre- 

 sented to us bv the inorujanic world. 



