336 



Belling. 



If we consider the 8 families in which the aborted ovules of the 

 parents are known, we have the following table, arranged according to 

 the percentage of aborted ovules in the progenies. 



LV-91 heads the list, in both parents aud progeny. LV-92, LV-468, 

 and LV-114, are at the bottom of the Ust, except for the large percen- 

 tage of full pods of the single parent plant of the family LV-468. 

 Hence it is certain that some genetic factors are concerned with the 

 nutrition of the ovaries, and segregate in the second generation. Among 

 others, those concerned with earliness aud lateness act in this way. 



The black plants make up three-sixteenths of the Fa plants; and 

 one-quarter, three-sixteenths, or three-quarters of several of the Fn families. 

 Since the pollen segregation into sound and half sterile occurs regularly 

 in these l)lack plants, they can properly be omitted in considering abortion 

 of ovules. For the sake of completeness, the following tal)lti is how- 

 ever given. 



Aborted ovules in distal halves of six pods. Black plants. 



The many other l)lack plants either did not flower, or dropped all their 

 flowers, or did not set six pods. 



Progenies of semi-sterile plants. — So much for the ovules of the 

 progenies of the fertile Fa parents. The progenies of the semi-sterile 

 Fä parents will now be considered. 



