Astragalus nuttallianus var. austrinus (Small) Barneby

Hamosa austrina Small, Fl. SE. U.S. 618, 1332. 1903
Astragalus Nuttallianus trichocarpus T. & G. Fl. N. Am. 1: 334. 1838.
Astragalus trichocarpus M. J. Young, Fl. Tex. 228, in part. 1873. Not A. trichocarpus Wall. 1868.
An annual; stem branched at the base, terete, strigose, 1-4 dm. long, often decumbent in age; leaves 2-5 cm. long; stipules lanceolate, acuminate, 4-5 mm. long; leaflets of the lower leaves mostly oval and obtuse, those of the upper elliptic or oblong or even linear and often acute, strigose on both sides, 5-12 mm. long; peduncles 3-8 cm. long; racemes very short, 3-8-flowered; bracts lanceolate, 1 mm. long; calyx strigose, the tube about 2 mm. long, the teeth 2-3 mm. long; corolla white or tinged with purple, 4-5 mm. long; banner obovate, retuse; wings nearly as long, the blade obovate or oblanceolate, somewhat falcate, with a reflexed auricle; keel-petals slightly shorter, the blade broadly lunate, acute or obtuse; pod strigose, 1.5-2 cm. long, 2 mm. wide and thick, arcuate towards the base, the cross-section cordate.
Type locality : "Rio Fronteras, Texas" [in reality Sonora].* Distribution: Texas to Colorado, Utah, Lower California, and Durango.

Hamosa subuniflora (Greene) Rydb. Bull. Torrey Club 54: 328. 1927.
Astragalus subuniflorus Greene, Leaflets 2: 42. 1910.
An annual; stem branched at the base, 1-1.5 dm. high, strigose; leaves ascending, 4-6 cm. long; stipules lance-subulate, 4-5 mm. long: leaflets 5-9, linear-oblanceolate or lance-linear, 5-13 mm. long, sparingly long-strigose on both sides, acute at each end; peduncles 4—7 cm. long; racemes 1-2-flowered; bracts subulate, 1-2 mm. long; calyx strigose, the tube about 2 mm. long, the teeth subulate, 2 mm. long; corolla apparently white, 6 mm. long, similar to that of H. Emoryana; pod arcuate, about 1.5 cm. long, 2 mm. wide and thick, glabrous, slightly sulcate on the lower suture.
Type locality: Near Tehuacdn, Puebla. Distribution: Known only from the type locality.