OF MUTANT CHARACTERS. 147 



TABLE 15. Summary of cross-over data involving black continued. 



The zero position in the second chromosome has been delegated to 

 star, which is found to be 46.5 units to the left of black, that is, black is 

 at an approximate position of 46.5 on the map as recast with star as the 

 zero-point. Table 15 gives a summary of all the cross-over data 

 previously published as well as that given in other sections of this paper. 



