168 
appeared. Raimann’s conclusions are based on Spach’s work, but 
he has presented them in a much more satisfactory manner than 
was indicated by the earlier author. 
The committee which prepared the List of Pteridophyta and 
Spermatophyta of Northeastern North America,* adopted Rai- 
mann’s interpretation, and it was suggested by Dr. Britton that I 
make an examination of the material in the Herbarium of Colum- 
bia University to ascertain to what extent the characters hitherto 
assigned for generic lines held. The study has been interesting 
both from a generic and a specific standpoint in_ exposing the 
strong tendency to mass, and to maintain composite species and 
genera where clear and constant characters exist both in habit and 
in the more minute morphology. 
The following pages contain the results of these observations 
on the North American species. 
I will be glad to receive additional material, either specimens 
or seeds, for examination. Proposing to present a monograph of 
this group at an early day. : 
Key to the Genera. 
Flowers regular (stamens equal in length.) 
Stigma deeply four-cleft, its segments linear. 
Ovules and seeds horizontal, inserted in two or rarely in several rows, pris- 
' m.tic-angled. I. ONAGRA. 
Ovules and seeds ascending, not angled. 
Buds erect ; flowers yellow ; ovules and seeds in one row. 
2, OENOTHERA. 
Buds drooping ; flowers pink ; ovules and seeds in two rows. 
a ANOGRA. 
> 
Stigma entire or rarely four-toothed. 
Ovaries and capsules sessile or nearly so, sabeloipad or elongated. 
Calyx-tube longer than the ovary. 
Stigma capitate; calyx-tube slender, usually adherent to the style. 
10, TARAXIA. | 
Stigma disk-like ; calyx-tube funnelform. 11. GALPINSIA, 
Calyx-tube shorter than the ovary. 
Stigma disk-like, slightly four-toothed ; calyx-tube saan ¢ funnel- 
form, sometimes twice shorter than the ovary. _ 
12, MgRIOLIX. 
Stigma capitate; calyx-tube campanulate or somewhat funnel form, 
many times shorter than the ovary. 
* Mem. Torr. Club, 5. 
i 
