42 THE METHODS AND 



there are nine distinct kinds of matings that 

 can be made between the variety, the type 

 and the hybrid, and the scheme fits the whole 

 group of results. It is based on two suppo- 

 sitions : 



1. That the female is cross-bred, or as 

 we call it heterozygous for femaleness-factor, 

 the male being without that factor. The eggs 

 are thus each destined from the first to be- 

 come either males or females, but as regards 

 sex the spermatozoa are alike in being non- 

 female. 



2. That there is a repulsion between the 

 femaleness-factor and the grossulariata factor. 



Such a repulsion between two factors we 

 are justified in regarding as possible because 

 we have had proof of the occurrence of a 

 similar repulsion in the case of the two 

 factors in the Sweet Pea. 



If the case of this moth stood alone it 



