Description from
Flora of China
Shrubs or trees, evergreen or deciduous, hermaphroditic, andromonoecious, or monoecious. Indumentum usually of stellate hairs or stellate or peltate scales. Buds perulate or naked. Leaves distichous or spiral, rarely subopposite or opposite, stipules minute to large, usually paired (solitary and enclosing bud in Mytilaria, and apparently absent in Rhodoleia); petiole usually well defined; leaf blade simple or palmately lobed, pinnately veined or palmately 3–5-veined. Inflorescences usually spikes or heads, rarely racemes or (condensed) thyrses or panicles, axillary or terminal. Flowers small to medium-sized, bracteate and often bracteolate, bisexual or unisexual, actinomorphic or rarely zygomorphic (Rhodoleia), hypogynous to epigynous, floral cup shallow to urn-shaped, sometimes absent; sepals 4 or 5(–10), sometimes absent, imbricate, usually persistent; petals absent or 4 or 5, yellow, white, greenish or red, often ribbonlike and circinate in bud, caducous; stamens 4, 5, or many, free, rarely arranged in 2 whorls with the inner whorl staminodal, development of polyandrous androecia centripetal or centrifugal; anthers basifixed, thecae mostly bisporangiate, each opening by two valves or a simple longitudinal slit, or monosporangiate and opening by a single valve (Exbucklandia, Hamamelis and the genera of the S hemisphere), connective protruding; disk scales sometimes present between stamens and carpels. Ovary 2-locular, carpels free at apex; ovules mostly 1 per carpel, less often many, but then most of them sterile, crassinucellar, bitegmic, anatropous, halfway between apotropous and epitropous, pendent from ovary top if solitary, along the carpellary margins if numerous; placentation axile. Styles and stigmas 2. Fruit a capsule, dehiscing septicidally, septifragally, or loculicidally and 4-valved; endocarp woody or leathery, usually loose from leathery exocarp. Seeds 1 to many per carpel; if solitary then seed coat thick, hard, smooth and shiny, black or brown; if numerous then sometimes winged and only a few viable. Endosperm thin; embryo straight; cotyledons leaflike, radicle short.
Several genera and species need critical revision.
About 30 genera and 140 species: E and S Africa (including Madagascar), E, W, and SE Asia, NE Australia, Central, North, and South America, Pacific Islands; 18 genera (four endemic) and 74 species (58 endemic) in China.
(Authors: Zhang Zhiyun, Zhang Hongda (Chang Hung-ta) ; Peter K. Endress)
Chang Hung-ta. 1979. Hamamelidaceae. In: Chang Hung-ta, ed., Fl. Reipubl. Popularis Sin. 35(2): 36–116.