508 FABACEAE 



cxirved. Astragalus Forwoodii S.Wats. Hills: S.D. — Wyo. — Mont. Suhmont. 

 — Mont. Je-Jl. 



4. A. lineare Rydb. Stem grayish strigose, often tinged with purple, 2-4 

 dm. high; leaflets 9-15, linear, 1-2 cm. long, 1-2 mm. wide, grayish strigose; 

 raceme short; calyx densely black-hairy; tube 3 mm. long; teeth 2 mm. long; 

 coroUa about 8 mm. long, ochroleucous or tinged with purple; keel tipped with 

 dark purple; legume glabrous, stipitate; stipe 4-5 mm. long; body 25-28 mm. 

 long, convexly curved on both sutures, but much more strongly so on the upper. 

 Dry slopes: Alan. — Alta. — Yukon. Boreal — Mont. Je. 



5. A. glabriusculum (Hook.) Rydb. Stem 2^ dm. high; leaflets linear or 

 nearly so, 15-25 mm. long, glabrous or nearly so; raceme short, in fruit elongate; 

 calyx black-hairy; tube 3 mm. long; coi^oUa ochroleucous, 8 mm. long; keel 

 tipped with dark purple; pod glabrous; stipe 4-5 mm. long; body 2 cm. long; 

 lower suture straight or nearly so. Phaca glabriuscula Hook. A. glahriusculus 

 A. Gray. Gravelly slopes: Alta. — S.D. — Wyo. Suhmont. — Mont. Je. 



6. A. Macounii Rydb. Stem 5-6 dm. high, finely and sparingly strigose or 

 glabrate; leaflets 9-17, very thin, oblong or oval, 15-25 mm. long, obtuse, gla- 

 brous above, sparingly strigose beneath; calyx black-hairy; tube about 3 mm. 

 long; teeth 1 mm. long; corolla about 8 mm. long, cream-colored or white, tinged 

 with purple; stipe of the pod 2-3 mm. long; body acute at both ends, 15-18 mm. 

 long, 5 mm. wide. Astragalus Macounii Rydb. Mountains: B.C. — Alta. — 

 Colo. Suhmont.— Mont. My-Jl. 



7. A. ibapense (M. E. Jones) Rydb. Stem slender, grooved, minutely 

 strigose; leaflets 1-7, elliptic or hnear, the lower obtuse, the upper acute, 4-12 

 mm. long, minutely strigose, or the single one of the upper leaves 2.5-4 cm. long; 

 raceme 1-3-flowered; calyx strigose; tube 2 mm. long; teeth 1 mm. long; corolla 

 6 mm. long, white; keel purple-tipped; pod short-stipitate, 12 mm. long, 3 mm. 

 wide, densely strigose, flat; lower suture straight. Astragalus ibapensis M. E. 

 Jones. Mountains: w Utah. Je. 



8. A. elegans (Hook.) Rydb. Stem finely strigose or glabrous, erect or 

 decumbent at the base, 2.5-6" dm. high; leaflets 9-17, oblong to linear, 15-20 

 mm. long, obtuse; raceme lax, 5-10 cm. long, in fruit even 15-20 cm. long; calyx 

 black-hairy; tube 2.5 mm. long; teeth 1 mm. long; coroUa 6-8 mm. long, purple, 

 or ochroleucous and tinged with purple; pod ellipsoid, pendent, shghtly inflated, 

 sessile, black-hairy, 8-15 mm. long. Phaca elegans Hook. Astragalus oroboides 

 americanus A. Gray. A. minor M.B. Jones. A. eucomus B. L. Robins. Moun- 

 tains and woods : Lab. — Que. — S.D. — Colo. — Ida. — Alta. Suhmont. — Alp. Je- 

 Jl. 



9. A. Shearii Rydb. Stems slender, strigose and striate, about 2 dm. high; 

 leaflets 13-19, 5-8 mm. long, oblong, obtuse or retuse at the apex, glabrate above, 

 grayish strigose beneath; raceme short, 5-10-flowered; calyx-tube about 4 mm. 

 long, strigose, partly with black hairs; teeth short; corolla reddish purple, nearly 

 1 cm. long; pod oblong, 12-14 mm. long, glabrous, reticulate, sessile. Astragalus 

 Shearii Rydb. Mountains: Colo. Mont. Au. 



10. A. Brandegei (Porter) Rvdb. Stems adsurgent or ascending, branched, 

 strigose; leaflets 9-11, distant, hnear, obtuse, 5-15 mm. long, glabrous above, 

 strigose beneath; raceme short, 2-5-flowered; calyx strigose; tube scarcely 2 mm. 

 long; teeth 1 mm. long or less; corolla about 5 mm. long, white or cream-colored, 

 tinged with purple; legume oblong, 10-12 mm. long, strigose. A. Brandegci 

 Porter. Hills and bluffs: Colo.— Utah— Ariz. Suhmont. Je-Jl. 



34. HOMALOBUS Nutt. 



Perennial herbs, with rootstocks or woody caudices. Leaves alternate, odd- 

 pinnate, or sometimes simple. Flowers racemose, purple or ochroleucous. Calyx 

 campanulate. Keel obtuse. Pod several- or many-seeded, usually narrow, 

 perfectly 1-celled, without trace of a partition, with both sutures prominent, 

 usually more or less compressed, often flat. 



