Description from Flora of China
Shrubs often scandent, deciduous. Stems prostrate or climbing, with aerial roots. Winter bud scales in 2-4 pairs, dark brown, pubescent. Leaves opposite; leaf blade simple, margin entire, slightly serrulate, or roughly serrate. Inflorescence terminal, corymbose or forming a thyrse. Flowers both fertile and sterile or fertile only. Sterile flowers usually with 1 expanded sepal, petaloid, margin entire. Fertile flowers small. Calyx tube adnate to ovary; teeth persistent. Petals free, valvate in bud, falling early. Stamens 10, free; filaments filiform; anthers ovoid, apex obtuse. Ovary subinferior, obconical to turbinate, 4- or 5-loculed; placentation axile; ovules numerous. Style 1, short; stigma capitate, 4- or 5-fissured. Fruit a loculicidal capsule, obconical to turbinate, striate, apex projected or truncate. Seeds very numerous, fusiform, with long, narrow wings at both ends.
About ten species: China, Japan, Korea; nine species (endemic) in China.
(Authors: Wei Zhaofen (Wei Chao-fen); Bruce Bartholomew)