64 INBREEDING AND OUTBKEEDING 



Gametes of Male 

 All direct segregates 



50.0J6 



FIG. 21. Diagram to illustrate linkage breaks or "crossing-over" between the loci 

 containing the factors for the allelomorphic pairs. Gray body, black body and long wing 

 vestigial wing in Drosophila. (After Morgan.) 



A complete visualization of this series of matings is 

 given in Fig. 21. 



