Herbs annual, 23--110 cm tall, not drying black. Stems often many branched apically; branches slender, 1--4 per node. Basal leaves opposite. Stem leaves in whorls of 3 or 4; petiole to 3 cm basally; leaf blade ovate-oblong to lanceolate-oblong, 2--6 X 0.8--2.5 cm, abaxially sparsely long pubescent to glabrescent, adaxially sparsely pubescent, pinnatipartite to pinnatifid; segments 4--10 pairs, ovate to linear-oblong, incised-dentate. Inflorescences spicate, interrupted; proximal bracts leaflike, often longer than flowers. Calyx ca. 8 mm, scarcely cleft anteriorly, sparsely pubescent along veins; lobes 5, unequal, posterior one triangular, entire, lateral teeth larger, ovate, serrate. Corolla pale yellow, 0.9--1.7 cm; tube ca. 8 mm; beak semicircular, 8--9 mm; lower lip ca. 7 mm X 1.3 cm, ciliate, middle lobe subrounded, hoodlike. Filaments pubescent. Capsule enclosed by accrescent calyx, to 2 cm. Fl. Jul--Aug, fr. Aug--Sep.
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