SEX-LINKED INHERITANCE IN DROSOPHILA 



85 



The analysis is as follows: 



RbYX - RbYX 

 WByX - Wby 



Red yellow 9 

 White black d" 



Fi 



RbYXWByX Red gray 9 

 RbYXWby Red yellow d^ 



Gametes of Fi 



RbyX - RbYX - "WByX - WBYX 

 RbyX - RbYX - WbY - Wby 



Brown red 9 1 



Yellow red 9 3 



Black red 9 1 



Gray red 9 3 



Brown red d' 1 



Yellow red d' 3 



Gray white d 3 



Black white <d 1 



The result conforms fairly with expectation; the Yellow red 

 running behind. 



In the next crosses a third combination was present. Six large 

 classes are expected. 



LRB 9 by LWT cT 



