CHROMOSOMES AND M1T()( IIONDKIA 289 



should thank the mitochondria for focusing llie 

 attention of cytologists upon tlie cytoplasnn'c cl(»- 

 ments, since the belief is becoming more and more 

 general that hereditary phenomena are the result of 

 interactions between nucleus and cytophism and that 

 the latter may play a more important role than is 

 usually supposed. 



