14 THEORY OF ORGANIC EVOLUTION. 



length of the individual rows of micellae. Dynamic 

 influences have a decisive effect upon cohesion and 

 disruptive tensions. The groups of micellae of the 

 configuration already obtained exercise these dyna- 

 mic influences upon each other ; and these dynamic 

 influences can be modified by stimuli from without. 

 The idioplasm continually alters its configuration 

 with its growth in successive ontogenies, but com- 

 paratively very slowly, so that it makes a minute 

 advance from the germ of one generation to the 

 germ of the next. The summation of these incre- 

 ments of advance through a whole line of evolution 

 represents the race history of an organism, since the 

 latter is connected only by its idioplasm in unbroken 

 continuity with the micellar beginning of its race. 



9. DEFINITE NOTIONS REGARDING THE FUNCTION Or 



THE IDIOPLASM. 



A plasmic substance causes definite chemical and 

 physical changes only when it is present in a certain 

 condition of motion. The peculiar agency which 

 the idioplasm has in each ontogenetic stage of 

 development and in each part of the organism 

 depends on the activity of a definite group of micellae 

 in the cross section of the strand or of a complex 

 of such groups, while this local stimulus controls the 

 chemical and physical processes by dynamic influ- 

 ence and by transmission of a specific mode of 

 motion, even to a microscopically small distance. 



