Japan Flora: Dioecious herb; stems 50-70 cm. long, erect, 5-angled, few­leaved, glabrous except for short pubescence on upper part; radical and lower cauline leaves long-petioled, the terminal leaflets membranous, orbicular, deeply cordate, 8-13 cm. in diameter, palmately 5- to 7-cleft, the lobes ovate to narrowly so, long-acuminate, duplicate-toothed, green on both sides, thinly pilose on nerves or glabrous on upper side, with crisped yel­lowish brown pubescence near base beneath, the lateral leaflets 3 or 4 pairs, very unequal, the larger ones ovate, to 1-2 cm. long, the smaller ones 2-3 mm. long, the stipules of the cauline leaves semi-ovate, erect, acuminate, toothed, 1-1.5 cm. long; corymbs terminal and in the upper axils, the branches and pedicels white-pubescent; flowers unisexual, white; calyx-lobes elliptic, glabrous; petals 5, spreading, glabrous, 3.5-4 mm. long; stamens about 30, usually slightly longer than the petals in the staminate flowers, much shorter than the petals in the pistillate flowers; fruiting carpels 5-6, glabrous, sessile, loosely contorted, nearly orbicular-ovate, about 3 mm. long, the stigma small, hemispheric. July. High mountains.

Shikoku, Kyu­shu; rare.