i6 



BOTANICAL GAZETTE 



[JANUARY 



hardly have any empty grams, and I did not think it necessary to 

 control this. 



The laeta have hardly any empty grains, but the figures for 

 velutina fall short of this, even as in other instances. In the last 

 place, I counted the germs in the hybrids of the crosses with La- 

 marckiana, self -fertilizing their specimens of each of the types: 



The lucida have almost no empty grains; the figures for hybr. 

 rubrinervis are the same as those for the mutant of that name, but 

 those for the Lamarckiana type give an unexpected result. In two 

 cases they are the same as for the species, but in the third the empty 

 grains have almost wholly disappeared. This latter specimen has 

 lost all the external marks of O. deserens and O. rubrinervis, but 

 kept the absence of the lethal factors. Its progeny splits into 

 Lamarckiana, lucida, and rubrinervis , and the first of these forms 

 repeats the splitting in the following generation. 



0. Lamarckiana nanellaX rubrinervis. — As in so many 

 other cases, the crosses with dwarfs can give a verification of those 

 with the species itself. In Gruppenweise Artbildung (p. 215) I have 



