Heredity - 493 



*&% 



41°£ 



Qi 



Fig. 26-16. Incomplete linkage: Fj female, from cross of black-vestigial and 

 gray-long, back-crossed to black-vestigial made. (Adapted from Morgan.) 



somes break at corresponding points, and an 

 exchange of connections occurs at the rup- 

 tured points. If the break takes place between 

 any two genes, the linkage between these 

 genes is changed. In the present case, for 



example, this change in the linkage relations 



is from 



\b 

 \v to 



F 



in a certain percent- 

 age of the gametes. 



Localization of the Genes in the Chro- 



