56 LEGUMINOS^;. (PULSE FAMILY.) 



heads hemispherical: involucre of 2 broadly stipuled Sfoliolate haves: ovary 

 one-oruled. — Watson, Bot. King's Exp. 60, t. 8. W. Wyoming and N. E. 

 Utah. 



*- 1- Slender annuals, glabrous : lobes of the involucre laciniately and sharply 



toothed. 



11. T. involucratum, Willd. Branching from the base : leaflets mostly 

 oblanceolate, acute at each end, spinulosely-serrulate : flowers in close heads, purple 

 tipped with white: calyx-teeth thin: ovules several. — From Mexico to the British 

 boundary, and from Colorado and New Mexico to the Pacific. 



12- T. pauciflorum, Nutt. Very slender: stems ascending or decum- 

 bent : leaflets obovate or oblanceolate or sometimes linear, usually obtuse or 

 refuse, serrulate : heads rather few-flowered : involucre small : flowers little ex- 

 ceeding the calyx, deep purple or light rose-colored : calyx-teeth rigid, selosely 

 acuminate : ovules two. — T. variegatum, Nutt., in Bot. King's Exp. and Hayd. 

 Pep. 1872. From Washington and Montana to S. California and Utah. 



5. HOSACKIA, Douglas. 



( 'alyx-teeth nearly equal, usually shorter than the tube. Petals free from 

 the stamens, nearly equal; keel somewhat incurved. Pod sessile, partitioned 

 between the seeds. — Herbaceous: leaves (in ours) 1 to 5-foliolate; stipules 

 minute and gland-like. — Watson in Bot. King's Exp. 432. 



1. H. TWrightii, (iray. Perennial: ashy-puberulent, bushy-branched, very 

 leafy : leaflets 3 to 5, apparently palmate and sessile, the lowest oblong, the rest 

 filiform-linear : peduncles short, rarely equalling the leaf, 1 to 2-flowered : calyx- 

 teeth setaceous-subulate, about equallinq the tube: keel not falcaiely-attenuate, 

 mostly very obtuse. — S. W. Colorado, New Mexico, and Arizona. 



■2. H. Purshiana, Benth. Annual: more or less silky-villous or sometimes 

 glabrous : leaves nearly sessile; leaflets 3 (or 1, rarely 4), varying from ovate to 

 lanceolate : peduncles exceeding the leaves, one-flowered : calyx-teeth linear, mih<7i 

 longer than the lube, about equalling the corolla : keel attenuated upward, falcate, 

 mostly acute. — From Washington to Northern Mexico, eastward to the Upper 

 Missouri, Arkansas, and N. Carolina. 



6. PSOEALEA, L. 



Two upper calyx-lobes often connate. Keel united with the wings. Sta- 

 mens mostly diadelphous. Pod sessile, thick and often wrinkled. — Perennial 

 herbs : leaves (in ours) digitate, the leaflets entire; stipules not adnate to the 

 petiole : flowers white or purplish. 



* Flowers in panicled racemes. 

 1. P. tenuiflora, Pursh. Slender, much branched and bushy, minutely 

 hoary-pubescent when young : leaflets varying from linear to obovate-oblong : 

 lobes of the calyx and bracts ovate, acute : pod glandular. — P. florilmnda, 

 Nutt. From Texas to Arizona, northward to the Missouri Kiver and eastward 

 into Illinois. 



