Dalea obreniformis (Rydb.) Barneby

Petalostemon obreniformis Rydberg, sp. nov
An annual, branched at the base; stems about 3 dm. high, glabrous, terete, branched; leaves ascending, 2-4 cm. long; stipules subulate-setaceous, 3-4 mm. long; rachis scarcely margined; leaflets 9-13, elliptic, 6-10 mm. long, glabrous, paler beneath; peduncles 1-7 cm. long; spikes slender, 1-4 cm. long, about 5 mm. thick; bracts inverted-reniform, apiculate, dark, with white or light margins, glabrous, conspicuously glandular-dotted; calyx about 2.5 mm. long, silky-pubescent; lobes ovate, acute, 0.75 mm. long; corolla dark-blue; blade of the banner suborbicular, truncate at the base, 1 mm. long, fully 1.5 mm. wide, the claw 2 mm. long; pod hairy above.
Type collected at the base of Mt. Mohinora, Chihuahua, 8 miles from Guadalupe y Calvo, August, 1898, E. W. Nelson (U. S. Nat. Herb. no. 332883).