262 C. W. METZ. 



The cases involving different cross-over values in homozygous 

 strains of Drosopklla (C ri of Sturtevant, and unpublished data 

 kindly furnished by Dr. Bridges) provide a closer analogy. At 

 present it can only be said that the chromosome behavior in 

 Dasyllis illustrates a type of mechanism which should give results 

 similar to those observed in Drosophila. 



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