No. 591] HYBRIDISM IN AN GIOSPEBMS 135 



bution with E. latifolium, are almost uniformly character- 

 ized by a high degree of perfection. To be specific, speci- 

 mens from Ontario, western Quebec, and New Hampshire 

 and Massachusetts show pollen perfectly developed or at 

 most with a few grains disorganized. Mr. Forsaith ex- 

 tended his investigation, again through the courtesy of 

 the Gray Herbarium, to the other genera and species of 

 the Onagraceae, with similar results. The investigation as a 

 whole will be described elsewhere, but it will be necessary 



to consider a few more illustrations in the present connec- 

 tion. There is one quite monotypic species in the order, 

 namely Zauschneria. It was found that in this the pollen 

 is practically perfect and the same state of affairs is pres- 

 ent in the two geographically limited species of Gongylo- 

 carpus, one occurring in Vera Cruz and the other on the 

 opposite side of the continent in Lower California. The 

 general situation in the case of the OnagraceaB, a family 

 much in the foreground at the present time by reason of 

 the investigations of De Vries and his disciples, is that 

 monotypic species or those geographically isolated have 



