96 PITTONIA. 
more distinct from the natural genus Roripa; nor do I see 
how, with its long subclavate styles and thin partitionless 
pods, it can be made out congeneric with even Armoracia, to 
which it is related. Asa perfectly acceptable genus—mono- 
typic, unless certain North Asiatic species prove congeneric— 
I have named it in honor of a long neglected but most de- 
serving name in American botany, that of Dr. Lewis C. Beck. 
RoRIPA TENERRIMA, Greene, Eryth. iii. 46. To the orig- 
inal account of this species the following is now to be added : 
growing parts, especially of the inflorescence and even te 
the half-grown ovaries, minutely scabrous: flowers alto” 
gether green—not at all yellow—the minute pale petals 
much shorter than the green sepals and nearly concealed 
by them. 
Having myself detected last summer, in western Nevada, 
a plant which upon comparison proves identical with the - 
type collected by Mrs. Austin, I have been able to identify 
with the species many sheets long kept in my herbarium 
under other names. The typical form, as found by myself, 
inhabits stream banks deeply shaded, and is more slender 
than most of the specimens ; but the plant as found in open 
ground is always slender, diffusely branching and depressed, 
and the minute roughening of the growing parts is here 
more obvious. The species is common along the lower 
Humboldt and Truckee rivers in western Nevada and east- 
ern California. A form of it, with shorter pods—these ovate 
or ovate-lanceolate in outline—is in my herbarium from 
Mr. Suksdorf, as obtained by him on *sandy bottom lands 
near Bingen" in Washington, 1894. It appears to have 
been named as Nasturtium obtusum by him, as it also was by 
Mr. Canby, who distributed it from the banks of the Yellow- 
stone in 1882. 
RonrPA TRACHYCARPA. Nasturtium trachycarpum, Gray, 
Bull. U. S. Geol. Surv. ii. 233. This plant of the valley of 
