THE MECHANISM OR SEX-DETERMINATION 67 



these are now mated, they produce, in equal numbers, 

 long-winged males and females and miniature-winged 

 males and females. 



The same relations may again be illustrated by body 

 color. 



xx 



XXXIX 



FIG. 38. Sex-linked inheritance of short ("miniature") and long wings 

 in Drosophila. Parents, short -winged $ , long-winged 9 Fi long-winged 

 $ and 9 F 2 long-winged 9 and $ and short-winged $ . Sex chromo- 

 somes to right. Open X carries short wings. 



A male appeared with yellow wings and body. Mated 

 to wild gray females he produced gray males and 

 females. These mated to each other gave gray females 

 (50%), gray males (25%), and yellow males (25%). 



As before, yellow females were made up. Mated to 

 gray males they gave gray females and yellow males. 



