A herb 16–24 in. high; stem straight, erect, simple or sparingly branched, nearly glabrous; internodes 1 1/3–3 in. long. Leaves sessile, linear, 15–22 lin. long, 1–1 1/2 lin. broad, acute or very acute at the apex, cuneate at the base, remotely and sparingly toothed (2 or 3 teeth each side), glabrous, horny especially on the under side; upper leaves narrowly linear, up to 1 in. long, 3/4 lin. broad, entire, always distinctly hooked-revolute. Flowers few, axillary near the apex of the stem or branch. Pedicels 6–10 lin. long; bracteoles 0. Calyx 4–5 lin. long, tuberculate chiefly on the lobes; tube campanulate, 2 lin. long; lobes lanceolate-linear, 2–3 lin. long, very acute, spreading. Corolla rose; tube 10 lin. long, 1 lin. broad, cylindric, distinctly curved, shortly glandular-pilose; limb 13–14 lin. in diam.; upper lip 1/2 in. long, 3/4 in. broad, 2-lobed; lobes of the lower lip obovate-orbicular, 6–7 1/2 lin. long, 5–7 lin. broad.
