NATURAL SELECTION SINCE DARWIN 61 



known, familiar and concrete facts, become in Weis- 

 mann's works real abstractions, metaphysical enti- 

 ties. The various parts of Weismann's huge sys- 

 tem, which covers all the problems relative to the 

 development of the individual and of the species, are 

 connected with one another by the idea of selection 

 and life-struggle. This idea, however, is made to 

 fit so many cases and is interpreted in so many differ- 

 ent ways that it gives the impression of the same label 

 affixed to the most dissimilar objects. 



The only thing which Darwin's natural selection, 

 Houx's histonal selection (the struggle between 

 parts of the organism) and Weismann's germinal 

 selection have in common is the word selection which 

 reveals similar tendencies in three different theories. 



We treat elsewhere in detail of Weismann's the- 

 ory; at present, we only wish to mention that his 

 works contain the most complete expose of the 

 Xeo-Darwinian doctrine with its overemphasis of 

 innate characters as against acquired characters, of 

 predetermination as against environmental action f 

 and with its too precise explanation of the evolution- 

 ary process and of its only factor, the lif e-struggle.^- 



In order to explain through natural selection a 

 fact which Darwin had not clearly elucidated, 

 namely, the presence of vestigial organs, Weismann 

 resorted to a special theory, the theory of panmixia. 



Of vestigial organs there are many examples 



