Flora of the Palouse Region 105 



T. pratense L. Perennial, erect or decumbent, rarely branched, 

 20-40 cm. high, somewhat pubescent throughout: leaflets elliptic or obovate, 

 obtuse or rarely emarginate, denticulate, 1-4 cm. long, frequently dark- 

 spotted near the middle; petioles short: heads globose or ovoid, sessile or 

 nearly so, 2 cm. long: flowers red, 10-12 mm. long; calyx-teeth subulate, 

 shorter than the corolla. Introduced and common. 



T. altissimum Dougl. Perennial from a thick root, erect, stout, glab- 

 rous: leaflets linear or oblong, narrowed at both ends, acute or obtuse, 

 cuspidate, 2-4 cm. long, strongly veined, the veinlets usually protruding as 

 slender teeth; stipules nearly as long as leaflets, acute, entire or nearly so: 

 peduncles 5-10 cm. long: heads globose or oblong, 2-3 cm. long: flowers red, 

 sessile, at length reflexed, 12-15 mm. long: calyx-tube strongly nerved, the 

 subulate teeth twice as long, the lowest straight, the others twisted. Low 

 meadows, common. 



170. HOSACKIA. 



Herbs or shrubs: leaves pinnate, 2-many-fbliolate; stipules 

 minute and gland-like: flowers yellow or reddish, solitary or in 

 umbels: calyx- teeth nearly equal: petals free from the stamens; 

 standard ovate or roundish: stamens diadelphous: pod linear, com- 

 pressed or somewhat terete, sessile, several-seeded. 



Flowers pinkish, solitary. H. purshiana. 



Flowers yellow and white, umbelled. H. bicolor. 



H. purshiana Benth. Annual, erect, usually branched, 30-60 cm. high: 

 leaves 3-foliolate, or the upper i-foliolate, nearly sessile; leaflets ovate or 

 lanceolate, silky-pubescent, acuminate, stalked, 6-20 mm. long: peduncles 

 as long as or longer than the leaves: flowers pink, 4-6 mm. long: calyx vill- 

 ous, the slender lobes twice as long as the tube, nearly equalling the corolla: 

 pod linear, narrow, often reflexed, glabrous and shining, 2-3 cm. long. 

 Sandy soil, common. 



H. bicolor Dougl. Glabrous throughout, erect or decumbent, 30-50 cm. 

 high, stout: leaflets 5-9, obovate, mostly obtuse, cuneate at base, 1.5-2 cm. 

 long: peduncles exceeding the leaves: flowers nearly sessile, spreading, 3-7 

 in an umbel: calyx about 6 mm. long, the teeth shorter than the campanu- 

 late tube: corolla yellow, the wings white, 2-2.5 cm - long: pod linear, nar- 

 row, 4-6 cm. long. Wet places, rare. 



171. PSORALEA. 



Perennial herbs, usually glandular-punctate: leaves mostly 3-5- 

 foliolate, with broad stipules: flowers usually in spikes or racemes: 

 calyx-lobes equal or the lower longest, the two upper ones some- 

 times united: corolla truly papilionaceous: stamens 10, diadel- 

 phous or sometimes monadelphous; anthers of two kinds: ovary 

 sessile or short-stalked, i-ovuled: pod seldom larger than the 

 calyx, thick, often wrinkled, indehiscent, 1 -seeded. 



