94 EGBERT W. HEGNER 



ments. The final conclusion is, then, that the size of the 

 organism and the characteristics correlated with size are 

 dependent upon the chromatin mass; that changes in these char- 

 acters are not due to cytoplasmic nor chromidial influence, but to 

 qualitatively unequal nuclear divisions, resulting in two types of 

 daughter nuclei differing in the determiners that control the 

 growth of»the chromatin, and that other characters that vary 

 independently must be controlled by other determiners within 

 the nuclei. 



Summaries of results will be found on pages 31, 59, 65, 

 and 76. 



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