104 



T. H. MORGAN 



Lethal and eosin vermilion 



Twenty-nine females of the original 789 9 to IGd'cf ratio were 

 bred to eosin vermilion males and gave the ratios recorded in 

 table 10 under i-xxiii. Some of these females from one culture 

 No. XVII, with a ratio of 98 :30, were again bred to eosin vermilion. 

 Their offspring are shown in the record of pairs of table 16. 

 Ten pairs gave a 1:1 ratio, and eleven a 2:1 ratio. As in the 

 case of the cross with white eyes it is the red-eyed class of males, 

 the lethal and also the double cross-over class which is deficient. 

 (One record jj with three cross-overs may be due to contami- 

 nation since the three occurred in the same bottle and in the same 

 count). 



TABLE 16 

 (From No. xvii of table 1) 



