PROBLEMS OF ORGANIZATION 



191 



stantly increasing reactivity towards the periphery. This concept is a 

 3 -dimensional translation of Dalcq's ('38) cortico-vegetal gradient and 



Figure i. 



according to it Dalcq's expression would be simply the resultant of the 

 activities of the multi-sphere relationships expressing their mobile 

 potentiality with reference to each other. Such a concept has the ad- 

 vantage of focusing attention upon the factors incident to the internal 

 configuration of the embryo which have received too little attention. 



This thesis does not deny the importance of the surface in the read- 

 justments of polar diflferentiation subsequent to fertilization. It also 

 would explain the sorting out of processes which occur in the early 

 period as well as the differences in bioelectric potentials which could 

 easily be the resultants of movements of differently charged particles 

 and their reactions during passing phases in which electrical fields 

 might be formed. 



