Erect branched or unbranched annual herb 4–40 cm. tall; stems glabrous or scabrid-papillate on the ribs. Leaf-blades elliptic-lanceolate, 1.2–6.5 cm. long, 0.6–2.8 cm. wide, acute to acuminate at the apex, cuneate at the base, thin, sparsely very shortly strigose-pubescent above, later glabrescent, margin usually pubescent, glabrescent beneath save for the midvein; petiole 2–5(–10) mm. long, glabrous or sparsely ciliate; stipule-sheath 0.5–1 mm. long, usually produced into a lobe 1.5 mm. long bearing 2–5 fimbriae 1–3 mm. long. Flowers not heterostylous, arranged in small heads 4 mm. wide, terminal or axillary, the heads often in threes; peduncle 0.2–1.5 cm. long; pedicels 0–1.2 mm. long. Calyx-tube subglobose, 0.5 mm. long, densely covered with short spreading hairs; lobes lanceolate, 0.7–2 mm. long, 0.5 mm. wide, ciliolate on the margins and midvein. Corolla white or tube green and lobes pale lilac, sometimes with a double mauve spot on each; tube very narrowly cylindrical, 3.2–4.5 mm. long, 0.4–0.9 mm. wide; lobes broadly elliptic, 0.4–1.8 mm. long, 0.4–1.2 mm. wide. Style 1.7–5 mm. long; stigma-lobes 0.4–1.2 mm. long. Capsule ± biglobose, 1.5 mm. tall, 2.2 mm. wide, densely covered with short spreading bristly hairs. Seeds black, ellipsoid, ± 0.5 mm. long, strongly reticulate.
