Great Bladdery Milkvetch

Phaca megacarpa Nutt.; T. & G. Fl. N. Am. 1: 343. 1838
Astragalus megacarpus A. Gray, Proc. Am. Acad. 6: 215. 1864. Astragalus megacarpus Parryi A. Gray, Bot. Calif. 1: 148. 1876. Tragacanlha megacarpa Kuntze, Rev. Gen. 946. 1891. Astragalus megacarpus prodigus Sheldon, Minn. Bot. Stud. 1: 136. 1894.
Perennial, with a cespitose caudex; stems mostly 1-7 cm. high, covered by numerous scalelike, persistent stipules; leaves 7-12 cm. long, ascending; stipules scaiious, deltoid, 5 mm. long; leaflets 7-21, broadly oval or obovate, 1-2 cm. long, 5-15 mm. wide, often retuse, glabrous and somewhat glaucous; peduncles 2-5 cm. long; racemes 3-S-flowered; calyx-tube campanulate, 9-10 mm. long, the lobes lance-subulate, 5-6 mm. long; corolla ochroleucous, nearly 2 cm. long; banner oblanceolate, gradually tapering below; wings shorter, the blade oblong-lunate, obtuse, only slightly falcate, shorter than the claw; keel-petals about 15 mm. long, the blade broader, rounded at the apex, a little more than half as long as the claw; pod glabrous, the stipe 3-5 mm. long, the body ellipsoid, 4-6 cm. long, 2-2.5 cm. wide; seeds obliquely reniform.
Type locality: Plains of the Rocky Mountains [Wyoming]. Distribution: Wyoming to southwestern Utah.