A NEW SEX-LINKED CHARACTER IN DROSOPHILA. 



TABLE V. 



Gametes of F2 white barred 9 , X w Br' X iv br' . 

 Gametes of Fo white barred cf , X w Br' . 



225 



By mating together white narrow barred females (homozygous), 

 and white barred males from the above experiment, a white 

 barred stock was obtained which has since bred true. 



The original mutant male was mated to his daughters (F if 

 Table IV.) and gave the expected proportions (Table VI.). 



TABLE VI. 



Gametes of Fi red barred 9 , X w br'X W Br'X W br'X w Br'. 

 Gametes of Pi red barred d" , X W Br' - 



Females. Males. 



Red Barred $. Red Barred cT- White Normal cf- White Barred cf. Red Normal tf. 



240 63 52 50 43 



RED BARRED EYE BY VERMILION NORMAL EY^E. 



The original barred male was mated to vermilion eyed 

 females with the results given in Table VII. As in the two pre- 

 vious cases the barred character was dominant and sex-linked, 

 appearing in the FI generation in the females only. The FI 

 females, as expected, were red and the males were vermilion, 

 since vermilion also is a sex-linked character. The F 2 generation 

 showed the expected sex-linkage results with four classes: 

 vermilion barred, red normal, vermilion normal, and red barred, 

 with an equality of males and females in each class. The ratios 

 of these four classes will be discussed later. 



In the following analyses v is the factor for the recessive sex- 

 linked character vermilion and Fis its normal allelomorph (red). 



