Japan Flora: Weedy herb with a tap-root and numerous brownish bulbils; leaves all radical, thinly pubescent, petiolate, the leaflets 3, thin, obcordate, 2-4 cm. wide, broadly cuneate at base; scapes 10-20 cm. long, slender, thinly pubescent; flowers 5-10, umbellate on the scape, 5-merous, nodding in bud, the pedicels slender, 1-3 cm. long; sepals with a pair of brownish glands; petals 12-15 mm. long, obovate-spathulate, rose-purple.
Naturalized; Honshu, Shikoku, Kyushu. Introduced from S. America.