Raceme rather dense, sometimes with a short branch below, 3–10(18) cm. long, up to 30–flowered; peduncle up to 14 cm. long; pedicels 1·5–3·2 mm. long, shortly crisped pubescent; bracts linear–lanceolate, 1·5–12 mm. long, often denticulate; bracteoles 0·6–3·2 mm. long.
Stamens 2–3 mm. long; filaments linear, free, somewhat dilated at the base, pubescent; anthers elliptic–oblong, 0·9–1·2 mm. long, short pubescent (hairs 0·1–0·2 mm. long) at the tip and usually also on the back of the connective.
Leaves sessile, up to 25–90 x 1·5–6 mm., linear to linear–lanceolate, often complicate, acute at the apex, attenuate at the base, thickened and sparsely serrulate at the margin, glabrous; midvein very prominent beneath.
Capsule subglobose, with 10 distinct nerves connected by some weak transversal nerves; valves 2–2·5 mm. long, inferior part of capsule 2–3 mm. long.
Stem single, unbranched or sometimes sparsely branched, ribbed, glabrous below, shortly crisped pubescent in the inflorescence region.
Calyx–lobes narrowly triangular, erect or sometimes reflexed, 1–2·8 mm. long, with 1–3 pairs of teeth at the margin, glabrous.
Hypanthium cup–shaped, 10–nerved, shortly crisped pubescent to subglabrous.
Seeds broadly elliptic in outline, flat, broadly winged, c. 2 x 1·5 mm.
Erect or somewhat twining herb, 20–70 cm. tall.
Ovary semi–inferior; style 1·2–2 mm. long.