Herb, 4–10 ft. high. Leaves 3 by 1 1/3 in. (or sometimes up to 8 by 3 in.); elliptic, acuminate, very sparsely hairy, base very narrowly truncate, subauricled; petiole up to 1–2 in. long; upper leaves smaller, often sessile, subcordate. Panicle often 6 by 3 in., terminal, very loose, sparsely glandular hairy; bracts 1/8 in. long, linear. Calyx 1/12 in. long, subequally 5-fid nearly to the base; segments linear-lanceolate, with few scattered glandular many-celled white hairs, otherwise glabrous. Corolla 3/4–1 in. long, light red, nearly glabrous; tube cylindric-funnel-shaped, much longer than the lips. Anther-cells muticous, widely separated one over the other; pollen globose, compressed, smooth. Capsule 2/3 in. long (whereof 1/3 in. is a cylindric stalk), narrow, 4-seeded; seeds small, scabrous with long tubercles.
