1 9 1 7 ] BE VRIES—OENO THERA 1 1 



were 0. HookeriXO. blandina and O. blandinaXO. Cocker elli. 1 

 These combinations would have given the twins laeta and velutina 

 if O. Lamarckiana had been used instead of 0. blandina. Now. 



however, 



showing 



mutant 



From 





only 



in the velutina condition. The former 



as a cure mutant 



8 



I shall now describe the single crosses as briefly as possible. 



O. syrticolaXO. blandina was made on 2 biennial plants of the 

 first named species in July 19 13, the pollen of a green blandina being 

 used in the one case, and that of a pale green one in the other case. 

 The seeds of the first one were sown in 19 14, those of the other in 

 191 5. Both of them gave cultures of 70 healthy offspring, making 



specimens 



fruits 



com 



June, before flowering. They were 



1 9 14 with the twins of O. syrticolaXO. cana, and in 191 5 with those 



from a cross of O. svrticolaXO. Lamarckiana. made in 101^ on a 



evidently 



specimen of the same group of biennial plants a; 

 with 0. blandina. All of the 140 hybrids were 

 and exactly like those of the control cultures. 



O. blandinaXO. biennis Chicago. — This cross was made on two 

 specimens of 1913, the pollen of the same parent plant being used 

 in both of them. They gave uniform cultures of 60 and 80 plants, 

 of which 25 and 10 were allowed to make long spikes of flowers and 

 fruits. The others were annual plants also, but were thrown away 

 in June, as soon as they reached a height of 30-40 cm., and showed 

 their marks so as not to leave the least doubt concerning their 

 velutina qualities. In 19 14 I compared them with the hybrids of 

 0. canaXO. biennis Chicago, and in 19 15 with th 



first 



figures of these species 



course 



admitted to be possible. As a matter 



see 



Grupp 



