No. 2.] ORGANIZATION OF THE EGG OF UNIO. 273 



the protoplasm must be endowed originally with all the " Fern- 

 krafte " of every localization of the entire ontogeny. But are 

 the " Fernkrafte " independent of the system .'' What sort of 

 science would this be.'' Yet Driesch appears, without actually 

 discussing these alternatives, at times to lean to this view. 

 For instance, p. 95 : " The actual adaptiveness of the process 

 appears thus in this case to be contained both in the causing 

 spot (verursachenden Ort) and the forces proceeding from it, as 

 well asm. \}i\Q system concerned." He explains this "appears," 

 on the next page, by saying that in reality the conception of 

 adaptiveness belongs only to the system, because this controls 

 by its absolute size the effective radius of the " Fernkrafte." 



Does the conception of "Fernkrafte" reduce itself to ab- 

 surdity or does it not } One must admit that it is often difficult 

 to extract the meaning from the welter of words, and so I may 

 have misinterpreted Driesch, though I have honestly tried to 

 understand and represent his ideas fairly. Driesch believes 

 his theory of "Fernkrafte" to be rational vitalism; I should 

 prefer to style it irrational mysticism. 



On the other hand, the theory of the bilaterality of the pro- 

 toplasmic elements appears to me a useful hypothesis, even 

 though it may be difficult to see that their endowment with 

 bilaterality alone is a logical halting ground. In the case of 

 the Qg^ of Ujiio, at least, the theory would seem to be of 

 greater use if we were also to postulate of the elements certain 

 antero-posterior proportions. 



That the entire organism in every stage of its development 

 exercises a formative influence on all its parts appears to me 

 an absolutely necessary hypothesis. Only thus can we explain 

 the reorganization of portions of the tgg or of the adult into 

 complete individuals, or form a satisfactory picture of the 

 maintenance of individuality. The theory of division of labor 

 needs reinforcing by a companion principle of unity of organ- 

 ization. The comparison of the metazoan body to a com- 

 munity or state is inadequate ; it is this inadequate conception 

 that has led to the extreme cell theory of development, as 

 upheld by Hertwig and the majority of zoologists. The mis- 

 conception may be traced back to Haeckel's comparison of the 



