Vor. II.] PEA FAMILY. 283 
7. Psoraleacollina Rydberg. Nebraska 
Psoralea. (Fig. 2092.) 
Psoralea collina Rydberg, Fl. Neb. 21: 54. / 6, 7. 
1895. 
Ascending or diffuse, somewhat grayish-pu- 
bescent, 1°-2° high. Stipules narrow, 1//-4’’ 
long; leaves 3-foliolate, or sometimes 5-folio- 
late; leaflets obovate or oblanceolate, mucro- 
nate, mostly glabrous above; bracts pointed, 
14//-2’” long; peduncles slender, 1/-4’ long; 
flowers about 3’’ long; calyx-segments linear- 
lanceolate, much shorter than the ovate pod, 
the lower one a little longer than the others; 
pod 2%4’/-3 long, tipped with a flat straight 
beak about 114’ long. 
Hillsides, western Nebraska. July—Aug. 
8. Psoralea digitata Nutt. Digitate 
Psoralea. (Fig. 2093.) 
sees digitata Nutt.; T. & G. Fl. N. A. 1: 300. 
1838. , 
Canescent with appressed hairs, slender, erect, 
widely branching, 1°-2° high. Petioles shorter 
than or sometimes a very little exceeding the 
leaves; stipules linear, 114//-2/’ long; peduncles 
much elongated, often 3-5 times as long as the 
leaves; leaflets 5, or of the upper leaves 3, digi- 
tate, short-stalked, oblong-linear or oblanceo- 
late, 9’/-18’’ long, 2//-3/” wide, mostly obtuse or 
mucronulate at the apex, narrowed or cuneate 
at the base; inflorescence spicate, interrupted, 
the blue flowers short-pedicelled or sessile in 
clusters of 3-5; corolla 4//-5/’ long, exceeding 
the broad mucronate bracts; calyx-lobes acute; 
pod ovoid, flattish, pubescent. 
Prairies, South Dakota to Kansas and Texas. 
June-July. 
g. Psoralea argophylla Pursh. Silver-leaf 
Psoralea. (Fig. 2094.) 
Psoralea incana Nutt. Fraser Cat. Name only, 1813. 
Psoralea argophylia Pursh, Fl. Am. Sept. 475. 1814. 
Erect, widely branched, densely silvery pubescent with 
white appressed hairs throughout. Stem often zigzag, 1°— 
3° high; petioles shorter than or equalling the leaves; 
stipules narrowly linear, 3/’-4/’ long; leaflets 3-5, digi- 
tate, very short-stalked, oval, oblong or obovate, obtuse 
and mucronate or acutish at the apex, narrowed or 
rounded at the base, 8//-15’” long, 3/’-6’’ wide; pedun- 
cles exceeding the leaves; inflorescence spicate, inter- 
rupted, the blue flowers sessile, about 4’’ long, in clusters 
of 2-4; bracts lanceolate, slightly longer than the corolla, 
persistent; calyx-lobes lanceolate; pod ovate, straight- 
beaked. 
Prairies, Wisconsin and Minnesota to the Northwest Terri- 
tory, south to Kansas and New Mexico. June-Aug. 
