Herb; stems erect or ascending, subquadrangular, sparingly and more or less bifariously puberulous, the hairs appressed or ascending, up to 0.25 mm. long; leaf blades lanceolate, up to 10.5 cm. long and 3.3 mm. wide, short-acuminate (the tip itself blunt), narrowed at base and decurrent on the petiole, moderately firm, entire or undulate, both surfaces puberulous, the hairs curved, subappressed or ascending, up to 0.32 mm. long, septate, those of the lower surface confined chiefly to costa and lateral veins (8 to 10 pairs), the venation scarcely prominent, but more so beneath than above, the cystoliths promi- nent, up to 0.16 mm. long; petioles slender, up to 3 cm. long, puberulous; panicles terminal and also axillary, the terminal ones about 8 cm, long and 6 cm. broad, moderately dense, the branches cymose, once or twice-forked, the lowermost internodes 1 cm. long, the others successively shorter toward tip of panicle, the pedicels rather slender, up to 5 mm. long, these and the internodes of the panicle more or less flattened, moderately to densely hispidulous, the hairs rigid, more or less spreading, straight or somewhat curved, septate; bracts subulate, up to 6 mm. long and 0.5 mm. wide, sparingly hirtellous; calyx segments linear, up to 8 mm. long and 1.25 mm. wide, the tip acute and recurved, ciliolate, the outer surface rather densely hispidu- lous, the hairs rigid, straight or slightly curved, whitish, septate, up to 0.25 mm. long, the inner surface of the segments sparingly and minutely hirtellous; corolla scarlet, minutely pubescent, the hairs up to 0.16 mm. long, spreading or ascending, septate, the tube nar- rowly hypocrateriform, 2.3 cm. long, about 2 mm. broad from base to about 8 mm. above base, thence first rather abruptly then gradually enlarged to 5 mm. at throat, the upper lip erect, slender, linear, conduplicate 1 cm. long, about 0.5 mm. wide from costa to margin, obtuse at tip, the lower lip slightly spreading, ovate, 7 mm. wide, rounded and 3-lobed at tip, the lobes about 0.75 mm. long and 1 mm. wide, obtuse or rounded at tip; stamens exserted 11 mm. beyond the mouth of the corolla, glabrous, the anthers linear, slightly curved, 4.5 mm. long, 0.75 mm. broad; style about 5 mm. longer than the stamens, glabrous, retinacula 2 mm. long, slightly curved, truncate and erose at tip, seed (immature) whitish, tuberculate. Type in the Gray Herbarium, collected in woods at base of a peak near Santa Elena, on the road from Medellín to Río Negro, Department of Antioquia, Colombia, 2,300 to 2,500 meters altitude, October 13, 1945, by W. H. Hodge (No. 6585). Habracanthus hispidulus is characterized by its mostly spreading, slenderly petioled, lanceolate leaf blades, its noticeably though minutely hispidulous calyces and axes of the inflorescence, and its bright scarlet corollas.