Herbs mostly climbing, rarely erect. Stems 0.5--6 m, often glabrous, or covered with yellow or brown, multicellular hairs. Petiole 3--11.5 cm; leaf blade cordate-orbicular, less often cordate-ovate, 5--15 × 3--15 cm, adaxially ± pubescent, apex often caudate. Cincinni with 1 to several flowers, in panicles, rarely cymes. Proximal bracts leaflike, 1.5--6 cm; distal ones smaller and ovate-lanceolate, rarely linear or lanceolate and boat-shaped. Pedicels absent. Sepals 3--5 mm, apex acute. Petals white or pale purple first, then turning white, linear or rarely filiform, 6--7 × (0.3--)1 mm, slightly longer than sepals. Capsule 4--7(--10) mm, with awn-shaped beak. Seeds gray-brown, 2.5(--4) mm. Fl. Jul--Aug, fr. Sep--Oct.

Tropical and subtropical forests, mountain slopes, subalpine areas; near sea level to 3200 m. Gansu, NW Guangxi, Guizhou, Hebei, W Henan, W Hubei, W Hunan, Liaoning, S Shaanxi, Shanxi, Sichuan, SE Xizang, Yunnan, W Zhejiang [Bhutan, India, Japan, Korea, Laos, Myanmar, Sikkim, Thailand, Vietnam].