ij6 Sex and Spurious A ' llelomorphism [CH. 



The whole series of facts is then consistently represented 

 as follows : 



i. lact. ? x gross. $ 



RR ? $ \DD$ $ 



FI gross. $ gross. 9 



DR& $ 



2. F l gross. 9 x f\ gross. $ 



composition DR 9 $ J)R <J $ 



gametes \ ffo \^^ 



i ' i 



2 gross. cJ i gross. 9 I fact- 



DD$ $ 



3. lact. 9 x F\ _ 



\ \ DR$ 



i gross. $ 



x lad. 



DR 



RR ? cJ 



In Doncaster's first series of experiments the numbers 

 observed were very wild and irregular, but more recently 

 he has repeated the matings and got numbers according 

 sufficiently well with those predicted by the scheme. The 

 spurious allelomorphism supposed to exist between female- 

 ness and the grossulariata factor would be a phenomenon 

 similar to that described already (p. 153) in the Sweet Pea, 

 where the factor for blueness and that for the erect standard 

 were shown to behave as if mutually repellent, and alterna- 

 tive to each other in the formation of the germ-cells. The 

 facts as to the limitations which sex introduces into the 

 descent of a varietal character are thus consistent with the 

 possibility that sex is a Mendelian character and that 

 femaleness is a dominant, depending for its development on 

 the presence of some definite factor, and that this factor has 



