CHAPTER X 



Germinal Selection. A Discussion of 

 Weismann's Theory 



A theory created in support of natural selection.— Roux's struggle 

 between the parts; the struggle between determinants. — 

 Advantages of the new hypothesis. — The idea of selection 

 applied universally. — A discussion of germinal selection. — 

 A discussion of Weismann's system; the theory of the germ 

 plasm, the representation of characters, the migration of 

 biophors. 



THE most important addition made by Weismann 

 to his system is the auxiliary theory of germinal 

 selection which is closely related to the theory of nat- 

 ural selection and answers many of the objections 

 which have been raised against the latter. The theory 

 of ger minal selectio n was not discussed in the chapters 

 devoted "to natural selection because it is based on the 

 theory of determi nants and is unintelligible unless 

 the theory of determinants has been previously ex- 

 pounded. 



The opponents of the theory of natural selection 

 are right on many points, Weismann concedes; the 

 fact that variations follow one another in a fixed 

 sequence, the development of complex organs with 



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