Japan Flora: Erect annual; stems 40-60 cm. long, terete, branched and short- puberulent, on one side in upper part; leaves rather thin, ovate-oblong or narrowly oblong, 1-3 cm. long, 3 (-5)-nerved, obtuse, obliquely rounded at base, toothed, sparsely long-pilose beneath; cyathia few on the upper part of the branchlets, the glands transversely elliptic; capsules smooth, glabrous, about 1.7 mm. across, trigonous; seeds tetrahedral-ovoid, 1-1.2 mm. long, dark brown, with 2 or 3 transverse wavy lines. Aug.-Sept.

Naturalized in lowlands; Honshu. N. Amer­ica; naturalized in Europe.