Uother 

 Kormal Eye 



Father 

 Bar /Bye 



Daughterd 

 Bar Eye 



Sons 

 Normal Kye 



Figure 9. Bar-eye and normal eye in Drosophila, and their method 

 of inheritance when a mother with normal eye is mated to a father 

 with bar-eyes. The dark area in each eye represents the region occu- 

 pied by the normal facets of the eye; in the bar-eyed individual this 

 is reduced to a narrow bar. Below each figure of the eyes are shown 

 the X-chromosomes of the individual, those from the mother (normal) 

 being shown in black, those from the father in white. All individuals 

 that have an X from the father (white) have the bar-eye. In conse- 

 quence the daughters are like the father, the sons like the mother. 



25 



