42 



SEX-LINKED INHERITANCE IN DROSOPHILA. 



In the third cross, vermiHon (gray) bar entered from one side ( 9 ) 

 and (red) sable (not-bar) from the other (cT). The daughters are 

 bar and the sons vermiHon bar. The daughters were back-crossed 

 singly to vermilion sable males and gave the data in table i6. 



Table 16. — Pi vermilion bar 9 9 X sable cf cf. 



sable cTcf, 



B. C. Fi bar $ X vermilion 



In the fourth cross, vermilion sable bar entered from one side, and 

 (red gray not-bar) wild type from the other. The daughters were bar 

 and the sons vermilion sable bar. The daughters were back-crossed 

 singly to vermilion sable males, with the results shown in table 17. 



