Japan Flora: Minutely pilose-papillose annual; stems scandent, slender, elongate, sometimes more than 1 m. long; leaves 3-6 cm. long, 2.5-4 cm. wide, acute to short-acuminate, cordate, the basal lobes rounded, the petioles 1-6 cm. long; sheaths short; flowers in short terminal and lateral spikes, or in fasci< cles in leaf-axils, rather long-pedicellate; fruit obovoid inclusive of the wing, decurrent on the pedicel, about 10 mm. long, pale green, accrescent after anthesis, the outer 3 perianth-segments winged on the back; achenes black, trigonous, cordate, about 4 mm. long, rather lustrous Aug.-Oct.

Hokkaido, Honshu (Kinki Distr. and eastw.). Sakhalin.