Japan Flora: Much-branched, slender, scandent perennial, nearly glabrous except for fine crispate hairs on nerves of upper leaf surface while young; larger leaves membranous, deltoid-ovate to broadly deltoid-lanceolate, 7-12 cm. long, 2-5 cm. wide, long-acuminate, shallowly cordate at base, often obscurely auriculate, puberulent on upper side, the petioles 15-3 cm. long; upper leaves smaller; inflorescence small, slightly branched, umbellike, usually shorter to slightly longer than the petiole, glabrous, the pedicels 3-10 mm. long; calyxsegments deltoid, small; corolla dark purplish, 5-7 mm. across, the lobes narrowly ovate, obtuse, white-pubescent inside; corona-lobes radially spreading, obovate, obtuse, shorter than the gynostegium; follicles horizontally spreading, narrowly lanceolate, 4δΈ€6 cm. long, 4-5 mm. wide, glabrous; seeds narrowly ovate, narrowly margined, about 6 mm. long. July. Mountains;
Hokkaido, Honshu, Shikoku, Kyushu; rather common.
Japan Flora: Nearly glabrous scandent herb with firm slender striate branches; leaves thick and rather firm, lanceolate to broadly so, 5-8 cm. long, 1-2 (-2.5) cm. wide, gradually acuminate, rarely acute, sometimes obtuse at base, glabrous except on midrib above, deep green and slightly lustrous above, pale green beneath, the petioles 5-12 mm. long; inflorescence much branched, as long as to slightly longer than the leaves, the pedicels 3-5 mm. long; calyx-segments ovate, slightly pilose; corolla 7-8 mm. across, purplish, the lobes ovate; corona-lobes orbicular, about half as long as the gyno- stegium; follicles narrowly lanceolate, about 9 cm. long. June-July. Warmer regions.