Appendix I. 189 



taining "somatic idioplasm " of such and such a grade, 

 plus " cytoplasm." For whether we thus follow Weismann's 

 earlier terminology or his later, we are so far speaking 

 about exactly the same thing, namely, the transformation of 

 "germ-plasm" into all the constituent cells of the "soma." 

 The difficulty is, in Vines' words above cited, " to con- 

 ceive that the germ-plasm of the ovum can impress upon 

 the somato-plasm of the developing embryo the hereditary 

 characters of which it (the germ-plasm) is the bearer"; 

 and Weismann says that this difficulty, which he acknow- 

 ledges, can now be answered by substituting for his 

 original statement that "germ-plasm" becomes changed 

 into " somato-plasm," the statement that it is " idio-plasm " 

 derived from " germ-plasm " which thus " impresses its 

 character on the cell containing it." But, " as a matter 

 of logical accuracy," there is surely here a distinction 

 without a difference. For what is the difference between 

 saying that germ-plasm "impresses" its character on the 

 contents of all somatic cells considered collectively under 

 the term "somato-plasm," and saying that every "onto- 

 genetic grade" of germ-plasm "impresses" its character 

 on each successive group of somatic cells considered sever- 

 ally under the term " idio-plasm " 01 such and such a 

 grade? At best this newer terminology has reference 

 merely to a superadded hypothesis touching the mode — 

 or rather the history — of the transition in question : it 

 does not affect the original and essential doctrine of the 

 transition itself. 



