100 



T. H. MORGAN 



In each generation the females that gave the highest sex- 

 ratio were selected to breed from. Whatever disadvantage this 

 method of selection may have, it at least makes more probable 

 the retention of a 2 : 1 ratio. 



TABLE 12 

 (From No. 16 of table 11) 



TABLE 13 

 (From No. b of table 12) 



