CYTOPLASM AND ACTIVATION OF THE GENE 



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prerequisites of orderly development, and this is tacitly assumed 

 when the action of the genes is being discussed. The specificity 

 of the cytoplasm probably increases with the systematic distance 

 of the forms, and it may find expression in crossing experiments 

 in a different result of the action of the same genes in different 

 cytoplasm. Thus far, however, no fact is known that would 

 force us to assume that specific hereditary traits exist that are 

 transmitted through the cytoplasm and are individually caused 

 by a genetic property of the cytoplasm. The plastids of plants 

 are probably a third independent constituent of the cell in regard 

 to heredity. 





