76 'APPENDIX. 



of the rejected individuals in the Une of the Horses? 

 Certainly they should be forthcoming in far larger 

 numbers than the individuals lying directly in the 

 path of development, for by our very assumption flie 

 latter were greatly in the minority in every generation. 

 Doubtless the question would be a proper one if our 

 eyes were sufficiently keen-sighted to assign tibe life- 

 value of the various minute differences tiiat distingni^ 

 the "better" from the "worse" individuals of every 

 generation. But this is a task whidi we can accom- 

 phsh at best only with selective processes which are 

 artificially directed by ourselves, as in the case of 

 doves and chickens, and even there only with the ut- 

 most difficulty and only with reference to a ^ng^ 

 characteristic and not with any spedes whidi to-day 

 exists in the state of nature. Picture, then, the diffi- 

 culties attending such a task as apphed to the meagre 

 fossilic bones of prehistoric species, touching whidi the 

 richest discoveries never so much as remotdy ap- 

 proach to the actual number of individuals that have 

 lived together for a single generation in the same lob- 

 itat. If the differences betw^n good and bad in a 

 single generation were striking enough to be imme- 

 diately remarked as such in fossil bcmes, the devdop- 

 ment of spedes would take place so rajndly that we 

 could directly witness it in Uving spedes. 



IV. RESfASKS ON THE HISTORY OF DBFUTITELY DIBECIED 

 VAKIATIONS. 



As to the attempt here made to apply the sdective 

 process to the elements -of the germinal substance (the 

 idioplasm) and thus to acquire a foothold for definitety 

 directed variation not blind in its tendency but pro- 



