PEA FAMILY 497 



7. H. leptocarpa (T. & G.) Rydb. Annual; stem erect, simple or branched 

 at the base, with ascending branches, 1-3 dm. high; leaflets 9-19, glabrous or 

 nearly so, oblong to cuneate, 3-8 mm. long, notched at the apex; peduncles 3-7 

 cm. long; raceme few-flowered; calyx-tube and the lanceolate teeth each 2 mm. 

 long; corolla purplish, 8-10 mm. long; legume linear, 2.5-3 cm. long, straight or 

 nearly so, glabrous. A. leptocarpus T. & G. Dry soil: Tex. Colo. Ark. 

 Son. Mr-Ap. 



7. H. atratiformis Rydb. Perennial; stem 2-3 dm. high, erect, branched, 

 strigose; leaflets 13-19, oblong, strigose below, glabrous above, 4-6 mm. long; 

 peduncles 5-7 cm. long; raceme lax, 2-3 cm. long; calyx black-strigose ; tube 

 about 2 mm. long; teeth subulate, 1 mm. long; "corolla ochroleucous, about 7 

 mm. long; pod linear, straight, minutely strigillose. (?) A. straturensis M. E. 

 Jones. Dry soil: s Utah. L. Son. 



24. TIUM Medic. 



Perennial caulescent herbs. Leaves alternate, with nearly free and distinct 

 stipules; leaflets numerous, entire. Flowers perfect, in racemes. Calyx 'cam- 

 panulate; teeth nearly equal, usually rather long. Corolla purple, white or 

 ochroleucous; banner with a rather broad, erect, often notched blade. Stamens 

 10, diadelphous; anthers alike. Pod narrow, tapering at each end, more or less 

 stipitate, usually membranous, 1-celled, obcordate, or inverted V-shaped in 

 cross-section, the lower suture strongly sulcate, rarely with a narrow partial 

 partition. Seeds numerous. 



Stipe exceeding the calyx; pod not incurved. 



Pod not black-hairy; corolla white or ochroleucous. 

 Pod erect, glabrous. 



Stipe much longer than the calyx. 1. T. eremiticum. 



Stipe scarcely exceeding the calyx. 

 Pod with a partial septum. 



Pod glabrous; stipe 34 mm. long. 2. T. atropubescens. 



Pod strigose; stipe 1 mm. long. 3. T. obscurum. 



Pod without septum. 4. T. arrectum. 



Pod reflexed. 



Plant villous; pod cordate in cross-section. 5. T. Drummondii. 



Plant appressed-pubescent or glabrous; pod more or less triangular or inverted 



V-shaped in cross-section. 

 Pod 23 cm. long; corolla 1520 mm. long. 



Calyx not black-hairy ; pod straight. 6. T. racemosum. 



Calyx black-hairy; pod arcuate. 7. T. scopulorum. 



Pod less than 1.5 cm. long; flowers 6-8 mm. long. 8. T. Rusbyi. 



Pod black-hairy; corolla violet or purple. 9. T. alpinum. 



Stipe shorter than the calyx or almost none; pod incurved. 

 Pod mottled ; plant green, very slender. 

 Stem slender, spreading. 



Raceme 1-5-flowered, short; leaflets obovate or orbicular. 



10. T. sparsiflorum. 



Raceme 5 10-flowered; leaflets linear. 11. T. owyheense. 



Stems stout, erect; raceme 5-15-flowered. 



Leaflets obovate or orbicular. 12. T. variegatum. 



Leaflets narrowly elliptic. 13. T. naturitense. 



Pod not mottled; plant cinereous. 



Pod appressed-pubescent. 14. T. humistratum. 



Pod hirsute- villous, with spreading hairs. 15. T. desperatum. 



1. T. eremiticum (Sheld.) Rydb. Stems several, 2-4 dm. high, glabrous 

 or nearly so; leaflets 13-19, 8-12 mm. long, oblong to obovate, obtuse; peduncles 

 8-10 cm. long; raceme 5-10 cm. long, loosely 5- 10-flowered; calyx strigose, with 

 black hairs; tube 5-6 mm. long; teeth subulate, 1-2 mm. long; corolla ochro- 

 leucous, 13-15 mm. long; stipe of the pod 10-12 mm. long; body oblong, 1.5-2 

 cm. long and 5 mm. thick. Astragalus eremiticus Sheld. A. arrectus M. E. Jones. 

 A. boiseanus A. Nels. Mountains and hillsides: Ida. Ariz. Nev. Son. 



2. T. atropubescens (Coult. & Fish.) Rydb. Stems several, erect, branched, 

 strigose or glabrous; leaflets 16-25, oblong, about 1 cm. long, obtuse, glabrate 

 above, strigose beneath; peduncles about 1 cm. long; raceme rather lax; calyx 

 strigose, with black hairs; tube about 4 mm. long; teeth lance-subulate, 1.5 mm. 

 long; corolla sulphur-yellow, 12-14 mm. long; body of the pod 15-18 mm. long, 



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