Japan Flora: Rhizomes elongate, 4-7 mm. in diameter, the internodes long; stems angled, 30-60 cm. long, ascending above; leaves oblong to narrowly oblong, nearly sessile, 5-10 cm. long, 2-5 cm. wide, glabrous, usually glaucous beneath; flowers 1-2, axillary, white, greenish near the tip, 15-20 mm. long, the pedicels 0.8-2 cm. long; filaments minutely papillose, the anthers about 4 mm. long, equaling to slightly longer than the filaments. Apr.-May. Meadows and thin woods in lowlands and foothills;

Hokkaido, Honshu, Shikoku, Kyushu; common. Korea and China. The typical phase occurs elsewhere in the temperate regions of the Old World.

var. thunbergii (Morr. & Decne.) H. Hara. Plant rather stout; stems 50-100 cm. long; leaves 8-15 cm. long, with minute papillae on the nerves beneath; flowers 2- 2.5 cm. long； Apr.-May. Mountains; Honshu.

var. maximowiczii (F. Schmidt) Koidz. Plant stout, 60-100 cm. high; leaves 10-20 cm. long, 3-8 cm. wide, the nerves beneath with minute papillae; flowers (l-)2-4, axillary, 22-25 mm. long. May-June. Hokkaido, Honshu (n. distr.). s. Kuriles, Sakhalin, and Ussuri.