380 DARWINISM TO-DAY. 



next to the cause or origin of variability the great desider- 

 atum is a knowledge of the means of cumulating and direct- 

 ing variability. And both these great fundamental needs 

 of a satisfactory understanding of organic evolution seem 

 to me to be wholly unreferred to in the theory of natural 

 selection. To be sure the control and cumulation of such 

 large differences among organisms and species as are posi- 

 tively sufficient to determine the saving or the loss of life 

 are explicable by selection. And this factor is sooner or later 

 in any phyletic history bound to step in and probably 

 be the dominant one. But a species, or a character, will 

 always have a longer or shorter preselective existence and 

 history, and it is precisely these days before the Inqui- 

 sition of which we demand information. For of one thing 

 we are now certain, and that is, that evolution and the origin 

 of species have both their beginnings and a certain period 

 of history before the day of the coming of the Grand 

 Inquisitor, selection. 



Finally there is still another desideratum and one whose 

 seeking will carry us into dangerous country. For while 

 there may be and are selectionists who might allow us to 

 fumble about in the darkness of preselective time for first 

 causes, there is probably none who will allow us to ques- 

 tion his right to explain that other element in evolution be- 

 sides species transformation, namely, adaptation, or, as the 

 Germans untranslatably put it, Zweckmassigkeit. But by 

 no means all biologists 6 find in natural selection a sufficient 

 explanation of adaptation. 



In the visible expression of organic evolution are two 

 chief elements, one the variety of life kinds, the existence of 

 species, the reality of lines of descent; and the 

 need of explain- other the adaptedness and adaptiveness of these 

 ing adaptation, life k m( j s . The varieties of organic kinds show 

 themselves adapted in structure and function to the varie- 

 ties of environment and life-conditions. Hence, the task 



