Japan Flora: Glabrous perennial; stems 10-30 cm. long, 4-angled; leaves ovate to broadly so, 1.5-4 cm. long, 1-2.5 cm. wide, subacute or obtuse, abruptly acute to broadly cuneate or sometimes rounded at base, loosely few- toothed, short-pctiolate or sessile in the upper ones; pedicels longer or slightly shorter than the leaves, 1.5-3 cm. long; calyx 8-10 mm. long at anthesis, 10-15 mm. in fruit, with 5 narrow wings, the teeth mucrolike, less than 1 mm. long; corolla pale yellow, 1.5-2 cm. long, with 2 lines of hairs in­side near tip; capsules oblong, 8-10 mm. long, enclosed in the persistent slightly inflated calyx； seeds minute, smooth. June-Aug. Wet places and along streams in mountains.

Hok­kaido, Honshu, Shikoku, Kyushu; common. Korea.