6o 



SEX-LINKED INHERITANCE IN DROSOPHILA. 



and 46 is due to the expected amount of double crossing-over. In fact, 

 for a distance as long as 58 an almost independent behavior of linked 

 gens is to be expected. 



Table 40. — Px cherry 9 9 X forked (^ d" . Fi wild-type 9 9 X Fi cherry cfcf. 



LINKAGE OF FORKED, BAR, AND FUSED. 



This value of 58 gave the furthest locus to the right obtained up to 

 that time, since forked is slightly beyond rudimentary. Later, the 

 locus for bar-eye was found still farther to the right, and the locus for 

 fused even farther to the right than bar. A cross was made involving 

 these three gens. A forked (not-bar) fused male was bred to a 

 (not-forked) bar (not-fused) female and gave bar females and males. 

 The Fi females were back-crossed singly to forked fused males with the 

 result shown in table 41. 



Table 41.— Pi bar9 9 X forked fused cf cf . 



X forked fused cf cf . 



B. C. Fi bar 9 



