52 



SEX-LINKED INHERITANCE IN DROSOPHILA. 



In one of the F2 male classes of table 28 the simple eye-color cherry 

 appeared for the first time (since the original mutant was vermilion as 

 well as cherry). Safir has recorded a similar cross with like results. 



Table 28. — Pi cherry vermilion cT cf X ^vild 9 9. Fi zvild-type 9 9 



X Fi wild-type cf cf • 



Some cherry males were bred to wild females. The Fi wild-type 

 males and females inbred gave the results shown in table 29. Some of 

 the cherry males thus produced were bred to their sisters. Cherry 

 females as well as males resulted; and it was seen that the eye-color is 

 the same in the males and females, in contradistinction to the allelo- 

 morph eosin, where there is a marked bicolorism (figs. 7, 8, Plate II). 

 The cherry eye-color is almost identical with that of the eosin female, 

 but is perhaps slightly more translucent and brighter. 



Table 29. — Pi cherry cf cf X wild 9 9. Fi wild-type 9 9 X Pi wild-typed" (f. 



COMPOUNDS OF CHERRY. 



In order to examine the effect of the interaction of cherry and white 

 in the same individual (2. e., white-cherry compound) cherry females 

 were crossed to white males. This cross should give white-cherry 

 females and cherry males. These white-cherry females were found 

 (table 30) to be very much lighter than their brothers, the cherry males. 

 The color of the pure cherry females and males is the same, but the 

 substitution of one white for one cherry lowers the eye-color of the 

 female below that of the cherry male. In eosin the white also lowers 

 the eye-color of the compound female about in the same proportion as 

 in the case of cherry. In the eosin the female starts at a higher degree 

 of pigmentation than the male and dilution seems to bring her down 



