214 THEORETICAL BIOLOGY 



Before the germinal areas are clearly established, various 

 changes in configuration have taken place, and these we can 

 also refer to invasion by polar systems. We shall assume that, 

 in the beginning, the polar systems were quite simple, as when 

 they induced the formation of a hollow sphere. After they 

 have established the fundamental type of the bilateral or 

 many-rayed system, they become more and more complicated. 

 The systems require to be very complicated that produce the 

 great variety of bony structure. 



The succession of the polar systems in time proceeds 

 according to a rhythm belonging to the organism itself, a 

 rhythm which changes from one type to another. 



THE IMPULSES 



The appearance, during genesis, of the polar systems with 

 their directives seems to point to a new factor that escaped 

 us when we were considering the genes. But that is not the 

 case. When we consider the Mendelian properties, the genes 

 of which lie ready prepared in the germ, we find that they 

 include not only chemical properties, but also properties 

 relating to form. We may confidently assume that the com- 

 ponents of the chromosomes represent the genes ; but in 

 considering the material basis of the genes we must not 

 forget their non-material aspect, and that lies in the impulse, 

 which follows the rule of the subject. 



As already explained, the material basis is probably a 

 ferment, which in a latent form lies waiting in the chromo- 

 \ somes. But, in addition, the gene consists of the non-material 

 impulse, and this it is which activates the ferment. 



As regards the chemical differentiation of the cells and the 

 formation of the micro-framework, we find no difficulty, but 

 try to refer their genesis to a simple fermentation, through 

 which the foamy framework gradually assumes the definitive 



