Vol.. II.] 



PEA FAMILY. 



Plants acaulescent, or nearly so, low, spreading; roots tuberous. 



Leaflets oblong-cuneate. 



Leaflets linear-oblong. 



Leaves pinnately 3-foliolate (the terminal leaflet stalked). 

 Racemes short, on peduncles about equalling the leaves. 

 Racemes spicate, elongated, much exceeding the leaves. 



Leaflets oblong-lanceolate, obtuse; pods 2" long, nearly orbicular. 



T *aoflo*-c r-<ro1-o_1or^r*1of*i o rii tn i ti Q tf* -nnH Q 1" c" Irmcr nVilinn^lv r*v 



28l 



11. P. esculenla. 



12. P. hypogaea. 



13. P. stipulate,. 



14. P. ped.uncula.ta. 



Leaflets ovate-lanceolate, acuminate; pods 4" -5" long, obliquely ovate. 15. P. Onobrychis. 



i. Psoralea lanceolata Pursh. Lance-leaved 

 Psoralea. (Fig. 2086.) 



Psoralea lanceolata Pursh, Fl. Am. Sept. 475. 1814. 



Erect, or assurgent, nearly glabrous, much branched, 

 densely dark-glandular, light green, i-2 high. Root 

 not tuberous; petioles equalling or shorter than the 

 leaves; stipules linear, 3 // -4 // long, early deciduous; 

 leaflets 3, digitate, sessile, sometimes with a few scat- 

 tered hairs, linear or oblanceolate, entire, varying from 

 acute to obtuse or even emarginate at the apex, nar- 

 rowed or cuneate at the base, 8 // -i5 // long, 2 // -4 // wide; 

 peduncles slender; spikes dense, short, 4 // -6 // thick, 6-10- 

 flowered; bracts membranous, caducous; flowers bluish- 

 white, 3 //r long; corolla 2-3 times as long as the calyx; 

 pod subglobose, about 2" long, sparingly pubescent, or 

 glabrous, punctate; seed globose, brown. 



In dry soil, Kansas to the Northwest Territory, west to 

 Arizona, Washington and British Columbia. June-July. 



-*^-s^-r 



2. Psoralea micrantha A. Gray. Small-flowered Psoralea. (Fig. 2087.) 



P. micrantha A. Gray; Torr. Pac. R. R. Rep. 4: 77. 1856. 



Assurgent, i high or more, from a horizontal root 

 or long slender rootstock often 3 in length; stems 

 glabrous, with scattered brown glands, and often with 

 broadly lanceolate or ovate scales at the base. Stip- 

 ules setaceous; leaves 3-foliolate, crowded; leaflets 

 linear or filiform -linear, ^ / -2 / long, the basal ones 

 oblong or cuneate-oblong; peduncles about the length 

 of the leaves; flowers about 2" long, white or bluish 

 in small heads or loosely scattered in short spikes; 

 bracts minute; calyx somewhat pubescent, glandular, 

 the lobes about equal; pod globose, over 2^" long, 

 glabrous, light brownish with raised darker glands 

 and a straight slender beak; seed globose, somewhat 

 flattened when dry, brown, smooth and shining. 



Prairies, Nebraska to Arizona. June-Aug. 



3. Psoralea tenuiflora Pursh. Few- 

 flowered Psoralea. (Fig. 2088.) 



Psoralea tenuiflora Pursh, Fl. Am. Sept. 475. 1814. 



Erect, finely appressed-canescent, especially 

 when young, punctate, much branched, slender, 

 2-4 high. Root not tuberous; leaves short-peti- 

 oled, digitately3-5-foliolate; stipules subulate, i"- 

 2" long; leaflets very short-stalked, entire, oval, , 

 oblong or elliptic, 6 // -io // long, 1%"-$" wide, ob- 

 tuse and mucronulate at the apex, narrowed or cu- 

 neate at the base; peduncles slender, longer than 

 the leaves; racemes loosely 6-i4-flowered, i / -3 / 

 long; bracts scale-like, persistent; flowers purplish, 

 2" long; corolla about twice the length of the 

 calyx; pod ovate, glabrous, punctate, 2 // -3 // long; 

 seed ovoid, brown. 



Prairies, Illinois and Minnesota to Texas and So- 

 nora, west to Colorado and Montana. May-Oct. 



