200 



GENETICS IN RELATION TO AGRICULTURE 



Vermilion XXY Female 



XT Synopsis 16% 



XX Synapsis 84% 



Dies(l) 



Wild Type Male ( 2) WUd Type Female (3) Wild Type Female (4) 

 Exception 



Fertilization 

 by Y Sperm 

 Of Wild Mate 1 



Vermilion Female ( 5 ) Dies (6 ) 



Exception 



Vermilion Male (7) Vermilion Male (8) 



FIG. 91. Secondary non-disjunction in the female. Diagram showing the constitu- 

 tion of an exceptional vermilion female, the two types of synapsis, reduction, and the 

 four classes of eggs produced. Each kind of egg may be fertilized by either of the two 

 (X and Y) kinds of sperm of the wild male, giving the eight classes of zygotes shown. 

 (After Bridges.) 



