Japan Flora: Glabrous perennial; stems erect, 40-80 cm. high, terete, slightly branched in upper part; leaves alternate or opposite, lanceolate, 6-10 cm. long, 1-2 cm. wide, acuminate, subsessile, deep green; in­florescence cymose, many-flowered, terminal; flowers blue, about 13 mm. across; calyx-lobes 1-2 mm. long; coroll a-tube about 8 mm. long, the lobes narrowly oblong, nearly as long as the cube; follicles obliquely spreading, 5-6 cm. long, gla­brous, terete; seeds narrowly oblong, 7-10 mm. long, obliquely truncate at both ends, brown, irregularly rugose. May-June. Grassy places along rivers in lowlands.

Hokkaido, Hon­shu, Kyushu. Korea and China.