DETERMINANTS. II 



If a phylogenetic line comes under the influence 

 of other external conditions and other external 

 stimuli than those which have hitherto acted upon 

 it, a new and corresponding arrangement of the 

 micellae appears phylogenetically in the idioplasm. 

 At the same time the other adaptation determin- 

 ants remain either undisturbed, or the new deter- 

 minant is formed at the expense of related deter- 

 minants which are already present and which may 

 at last entirely vanish. Hence along with growing 

 and complete determinants the idioplasm always 

 contains likewise weakened and vanishing deter- 

 minants. From the fact that a phylogenetic race is 

 thrown repeatedly among different external con- 

 ditions, it may at last unite in its idioplasm a large 

 number of developing, mature, and vanishing 

 adaptation determinants. This number is noticeably 

 increased if in consequence of interbreeding a 

 fusion of related idioplasms take place. 



8. DEFINITE NOTIONS WITH REGARD TO THE MOR- 

 PHOLOGY OF THE IDIOPLASM. 



Since in the phylogenetic development of the 

 plasma the thicker idioplasm is differentiated from 

 the more fluid soma-plasm ( 5), the former has 

 the tendency by nature to assume a reticular arrange- 

 ment. The strands of this network consist, in con- 

 formity with their origin, of parallel rows of micellae 

 extending lengthwise. These rows of micellas arc 



