INHERITANCE OF SEX AND RELATED PHENOMENA 



TABLE XXXVI. A COMPARISON OF CROSS-OVER VALUES FROM NORMAL AND NON- 

 DISJUNCTIONAL CULTURES IN DROSOPHILA (Data from Bridges) 



Vermilion XYY Male 



XY Synapsis 67% 



YY Synapsis 33% 



Reductio 



Sperm 



Offspring 



Fertilization of Eggs 

 of Sable Female 



Sable Male (1) Wild Type Female (2) Wild Type Female (3) Sable Mate (4) 



FIG. 92. Diagram of secondary non disjunction in the male. Four kinds of sperm 

 are produced, but none of these lead to the production of phenotypic exceptionsin Fi. 

 (After Bridges.) 



