PA PIL ION A CEA E. 543 



i. Psoralea lanceolata Pursh. Lance-leaved Psoralea. (I. F. f. 2086.) 

 Nearly glabrous, much branched, light green. 3-6 dm. high. Root not tuberous; 

 stipules linear. 6-9 mm. long, early deciduous; leaflets 3, sessile, sometime- with 

 a few scattered hairs, linear-oblong or oblanceolate, entire, narrowed or cuneate at 

 the base. 17-30 mm. long; peduncles slender; spikes dense, short, 9-13 mm. thick, 

 6-io-flowered; bracts membranous, caducous ; flowers bluish white, 6 mm. long; 

 corolla 2-3 times as long as the calyx; pod about 4 mm. long, sparingly pubescent 

 or glabrous, punctate; seed globose, brown. In dry soil, Kans. to S. Dak., the N. 

 YV. Terr.. Ariz.. Wash, and Br. Col. June-July. ' 



2. Psoralea micrantha A. Gray. S>v\.ll-flowered Psoralea. (I. F. f. 

 2087.) Assurgent. 3 dm. high or more; stems glabrous, with scattered brown 

 glands, and often with scales at the base. Stipules setaceous; leaves crowded; 

 leaflets 3. linear or filiform-linear. 1-5 cm. long, the basal ones oblong or cuneate- 

 oblong; peduncles about the length of the leaves; flowers about 4 mm. long, white 

 or bluish, in small heads or scattered in short spikes; bracts minute; calyx some- 

 what pubescent, glandular, the lobes about equal; pod over 6 cm. long, glabrous, 

 brownish with raised darker glands and a slender beak. Neb. to Ariz. June-Aug. 



3. Psoralea tenuifiora Pursh. Few-flowered Psoralea. (I. F. f. 2088.) 

 Erect, finely appressed-canescent, especially when young, 6-12 dm. high. Root 

 not tuberous; leaves short-petioled, 3-5-foliolate; stipules subulate, 2-4 mm. long; 

 leaflets short-stalked, entire, oval, oblong or elliptic, 1-2 cm. long, obtuse and 

 mucronulate at the apex, narrowed or cuneate at the base; peduncles longer than 

 the leaves; racemes 6-14-flowered; bracts scale-like, persistent; flowers purplish. 

 4 mm. long; corolla about twice the length of the calyx; pod ovate, glabrous, punc- 

 tate, 4-6 mm. long; seed ovoid, brown. Prairies, 111. to S. Dak., Tex., Sonora, 

 Colo, and Mont. May-Oct. 



4. Psoralea obtusiloba T. & G. Black-dotted Psoralea. (I. F. f. 

 2089.) Erect, 3-6 dm. high; stems canescent with appressed silky white hairs. 

 Stipules small, setaceous; petioles much shorter than the leaflets; leaves 3 -folio- 

 late, or the basal often 4-5-foliolate; leaflets 5-35 mm. long, oblong-obovate, retuse 

 or mucronulate, glabrous above, minutely canescent beneath; bracts small, ovate, 

 cuspidate; calyx canescent with white silky hairs; pod ovate, about 9 mm. long ; 

 seed compressed, obliquely ovoid. Kans. (?), Tex. to Ariz, and Mex. 



5. Psoralea floribunda Nutt Many-flowered Psoralea. (I. F. f. 2090.) 

 Stem 3-12 dm. high, branching, canescent, not glandular. Petioles mostly shorter 

 than the leaflets; stipules 3-7 mm. long, subulate; leaves 3-5- (sometimes 7-) folio- 

 late; leaflets 1-4 cm. long, oblong, rugose, glabrous or with a few scattered hairs 

 above, canescent with appressed white hairs beneath ; peduncles 5- 18 cm. long ; 

 spikes oblong or cylindric, the flowers about 9 mm. long, at length interrupted and 

 appearing as if whorled; bracts 2-3 mm. long, lanceolate, hirsute; calyx canescent, 

 the lobes triangular, acute; pod ovoid, glabrous, light brown, covered with darker 

 glands, its beak short, stout; seed 5 mm. long, compressed. 111. to Mont., Tex., 

 Ariz, and Mex. May-Oct. 



6. Psoralea linearifolia T. & G. Narrow-leaved Psoralea. (I. F. f. 

 2091.) Erect, 3-6 dm. high. Stipules 3-7 mm. long, lanceolate or setaceous; 

 leaves sessile or short-petioled, 1-3-foliolate; leaflets 11-31 mm. long, linear, 

 rugose, glabrous or with a few 'appressed hairs; peduncles 2.5-22 cm. long; flowers 

 blue, loosely scattered, 1-4 together on slender pedicels, 4-9 mm. long; bracts 

 2 mm. long, ovate, acuminate; mature calyx 4 mm. long, glandular, slightly pu- 

 bescent; pod 9 mm. long, narrowly ovoid or oblong, glandular, with a short stout 

 straightish beak; seed flat, oblique, brown. Prairies, Neb. to Tex. May-Aug. 



7. Psoralea collina Rydberg. Nebraska Psoralea (I. F. f. 2092.) Some- 

 what grayish-pubescent. 3-6 dm. high. Stipules narrow. 2-9 mm. long ; leaves 

 3-foliolate, or sometimes 5-foliolate ; leaflets obovate or oblanceolate. mucronate, 

 mostly glabrous above; bracts pointed. 3-4 mm. long; peduncles 1.5-10 cm. long; 

 flowers about 6 mm. long; calyx-segments linear-lanceolate, shorter than the ovate 

 pod. the lower one a little longer than the other-; pod 5-6 mm. long, tipped with a 

 flat straight beak about 3 mm. long. Hill-ides. W. Neb. July-Aug. 



8. Psoralea digitata Nutt. Digitate Psoralea. (I. F. f. 2093.) Canes- 

 cent with appressed hairs, 3-6 dm. high. Petioles shorter than or sometimes a 

 little exceeding the leaves; stipules linear, 3-4 mm. long; peduncles often 3-5 



