1. Sisymbrium hrachycarpum. Richards.—Hook. Fl. Bor. Am. 1. p . 62.— S. canescens. 5.
Torr. et Gr. Fl. 1. p . 92.
H a b . Snake Country. Confluence of Reed’s River with the Snake River. (Tolmie.)
2. S. curvisiliqua. Hook. Fl. Bor. Am. 1. p . 6 i .— Nasturtium . N u tt. in. Torr. et Gr.
Fl. l . p . 73.
H a b . Snake Country. (Tolmie.)
1. Erysimum asperum. D C .—Hook. Fl. Bor. Am. 1. p. 64>. t. 22. Torr. et Gr. F l. 1.
p . 95.— E. elatum. Nutt, in Torr. et Gr. F l 1. p . 95.
H a b . Snake Country ; about the American falls on the Snake River, and at Green River. (Tolmie.)
2. E . ? glaberrimum; foliis radicalibus spathulatis caulinis pinnatifidis supremis linearibus
integerrimis.
' H a b . Snake Country. Confluence of Reed’s River with the Snake River. (Tolmie.)—Root perennial,
bearing at the sun\mit several erect stems, scarcely a foot high, and their stems are simple. Lower leaves
spathulate, entire, soon withering; the principal ones of the stem pinnatifid; the uppermost ones linear,
entire : all glabrous, as is every part of the plant. Corymbs of several rather small flowers. Calj’x glabrous,
of four membranaceous ovato-lanceolate leaves. Petals yellow, but not very bright. Petals obovate, clawed,
nearly twice as long as the calyx. Young siliquæ narrow, linear.
1. Lepidium corymbosum; glabrum, ramis corymbosis, foliis pinnatifidis inferioribus
bipinnatifidis, floribus dense corymbosis, petalis 4, siliculis apteris (parvis) orbiculari-
ovatis obsolete emarginatis, stylo exserto.
H a b . Snake Country. American falls of Snake River. (Tolmie.)—A very distinct species. Root
annual. Whole plant glabrous. Stem erect, rigid, a span to a foot high, bearing, especially in the upper
half, several erecto-patent branches, the lower ones the largest, so that all the specimens have a very corymbose
appearance, and each branch bears several corymbs of largish white fiowers. Leaves 1-2 inches long,
pinnatifid ; the segments oblong, those of the lower leaves again pinnatifid. Corymbs very dense, and the
fructified racemes are very short. Siliculæ small, quite glabrous, broadly ovate, approaching to orbicular,
wingless, scarcely notched, and with a rather considerably exserted style.
2. L . latipesi humifusum cæspitosum, foliis bipinnatifidis, floribus densissimis, pedicellis
latissimis. planis, siliculis ellipticis reticulatis hirsutis antice bialatis alis rectis longitudine
siliculorum, stigmate sessili. Hook. Ic. P I t. 41. Torr. et Gr. F l l . p . 116,
This is a remarkable plant, of a singularly compact mode of growth ; the branches stout, downy, humifuse ;
the leaves many of them 3-4 inches long, glabrous, or only here and there ciliated, bipinnatifid ; the segments
linear. Corymbs of exceedingly numerous, very closely placed, small flowers, succeeded by broad crowded
racemes of fruit. Petals small, ciliated. Pedicels broad and quite flat, downy. Siliculæ large for the size
of the plant, elliptical, compressed, reticulated, more or less clothed with white hairs : the margin of the dissepiment
broad ; the apex on each side the minute sessile stigma extends into two acuminated wings, nearly
equal iu length with the pouch.
3. L . oxycarpum; subpubescens, caulibus procumbentibus gracilibus, foliis linearibus
integris vel pinnatifidis, fructus racemis laxis, pedicellis latis compressis patenti-reflexis,