Perennials, to 80 cm tall. Lateral roots slender. Rhizomes stout, to 3 cm in diam. Stems erect, hollow; lower stems soft and easily compressed at anthesis. Leaves on basal nodes scalelike, sparsely hairy. Petiole of other leaves less than 2 cm, broadly flattened, basally comose; leaf blade lanceolate-oblong to ovate, 3-7 cm, abaxially often hairy on veins, adaxially sparsely pubescent, base cuneate to obtuse, margin irregularly serrate or double serrate. Thyrses capitate or spicate, to 8 cm in fruit; cymes opposite, widely spaced, often to 4 pairs; peduncle glandular hairy. Pedicel glandular hairy. Calyx 4-5 mm; lobes ovate, glabrous to densely glandular hairy, apex acute. Corolla yellow-white or purple, ca. 9 mm, outside glabrous to glandular hairy, inside glabrous; tube somewhat inflated, ca. 5 mm; lower lip lobes small; upper lip ca. 2 mm longer than lower lip, lobes with overlapping margins. Stamens as long as corolla tube; staminode varying in shape. Ovary 2-3 mm. Style nearly as long as ovary. Capsule narrowly ovoid, 1-1.3 cm. Fl. Jun-Jul, fr. Aug-Oct.
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