The World Flora Online

Shrubs [trees]. Leaves deciduous [persistent], cauline, alternate, simple; stipules absent; petiole present; blade margins serrate. Inflorescences terminal racemes, solitary or in clusters. Flowers bisexual; perianth and androecium hypogynous; sepals 5, connate proximally; petals 5, connate proximally ca. 1/2 their lengths, corolla cylindric-urceolate; nectary disc absent; stamens 10, in 2 whorls of 5, outer whorl antipetalous, free, distinct or barely adnate to petals; anthers dehiscent by apical porelike slits; pistils 1, 3-carpellate; ovary superior, 3-locular; placentation axile; ovules anatropous, unitegmic, tenuinucellate; styles 1, hollow; stigmas 3, linear. Fruits capsular, dehiscence loculicidal, enclosed by persistent calyx. Seeds [6-]40-100, brown, oblong-ovoid; embryo straight; endosperm oily, well differentiated.

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Trees or shrubs, evergreen or deciduous. Buds, branches, leaf blades, inflorescences, and flowers with sparse to dense usually stellate hairs, often mixed with simple hairs. Branches sympodial, usually pubescent at least when young. Stipules absent. Leaves alternate, simple, generally crowded near apex of twigs; leaf blade usually abaxially ± pubescent and adaxially glabrous or glabrescent, margin serrate or occasionally entire. Inflorescences terminal, usually a many-flowered slender raceme, either solitary or umbellate-clustered, sometimes sparsely branched near base and thus appearing paniculate, pubescent, bracteate. Flowers bisexual, actinomorphic. Pedicel articulated at base of sepals. Sepals 5, imbricate, persistent. Petals 5, usually white, free or coherent at base, oblong to obovate, inside often pilose from base to middle, apical margin often fimbriate, apex rounded- to truncate-emarginate. Stamens 10, in 2 whorls, distinct but generally adnate to base of petals; anthers inverted at anthesis, ± V-shaped, introrse, papillose, opening by short apical pores. Ovary superior, 3-locular, globose but apically depressed at style base, pubescent, with axile placentation; ovules 20–40 per locule. Style 1, persistent, apex usually 3-cleft or -lobed. Capsule subglobose to globose, pubescent, 3-locular. Seeds many, ovoid-subtrigonous, thin-walled, surface impressed-reticulate.

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• 3
• 1
]. 

Fls perfect, hypogynous, regular, mostly 5-merous; sep persistent, connate below, the lobes imbricate; pet imbricate, distinct or nearly so; stamens bicyclic, free or barely adnate to the base of the pet; anthers becoming inverted in ontogeny, deeply sagittate, the free tips of the pollen- sacs appearing apical, each opening by a slit-like distal pore; pollen in monads; ovary superior, trilocular, often nectariferous at the base; ovules numerous on axile placentas; fr a loculicidal capsule; seeds numerous, often winged, with copious endosperm and a short, dicotyledonous embryo; seed-coat a single layer of cells; shrubs or small trees, usually stellate-hairy, with simple, exstipulate lvs and small, white (or pinkish) fls in racemes or panicles. 1/65.

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• 6
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SELECTED REFERENCES Schneider, J. V. and C. Bayer. 2004. Clethraceae. In: K. Kubitzki et al., eds. 1990+. The Families and Genera of Vascular Plants. 9+ vols. Berlin etc. Vol. 6, pp. 69-73. Thomas, J. L. 1961. The genera of the Cyrillaceae and Clethraceae of the southeastern United States. J. Arnold Arbor. 42: 96-106.

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• 2
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