Description from Flora of China
Shrubs or small trees, unarmed, often deciduous; buds conical. Raphides absent. Leaves opposite, distichous or decussate, usually with domatia; stipules persistent or deciduous, interpetiolar, bifid, nodes with a ring of persistent trichomes exposed after stipules fall. Inflorescences terminal and/or in axils of uppermost leaves, capitate with 1[to several] globose heads, pedunculate with peduncles usually articulate in basal half and bearing stipuliform bracts at middle, many flowered, bracteate; bracteoles linear to linear-spatulate. Flowers sessile, bisexual, monomorphic. Calyx limb 5-lobed. Corolla white, salverform to slenderly funnelform, glabrous inside; lobes 5, valvate in bud. Stamens 5, inserted in upper part of corolla tube, partially to fully exserted; filaments short, glabrous; anthers basifixed. Ovary 2-celled, ovules many in each cell, pendulous on axile placentas attached to upper 1/3 of septum; stigma globose to obovoid, exserted. Fruiting heads globose, at maturity shattering easily. Fruit capsular, obconic, septicidally then loculicidally dehiscent into 4 valves separating from base to apex from each other and from septum, cartilaginous to papery, with septum persistent or tardily deciduous, with calyx limb persistent on septum; seeds numerous, small, fusiform to oblanceoloid, flattened to rounded, with embryo portion obovoid, ellipsoid, oblong, or trigonous, sometimes with short wing at one or both ends.
Four species: China, Japan, Korea, Thailand, Vietnam; three species in China.
(Authors: Chen Tao (陈涛); Charlotte M. Taylor)