SEX-LINKED LETHALS IN DROSOPHILA 



115 



which it really lies. The following list will serve to recall the 

 possible combinations in the gametes of the Fi female. 



Non-cross-over. 



Single cross-over ' 



Double cross-overs 



In table 26 the available data are given in the first four columns, 

 and the percentage distance between eosin and lethal, and lethal 

 and vermilion, and eosin and vermilion in the following three 

 columns. The calculations are given for the experiments taken 

 singly, and for the totals. There is again a considerable discrep- 

 ancy in the separate counts. The totals show that lethal lies 

 between eosin and vermilion, but nearer to eosin. The total 

 percentage distance between eosin and vermilion is 27.9. 



As before, a calculation from the total data was made, table 27, 

 on the basis of the male and female cases taken together, which 



TABLE 26 



