Barkley, Theodore M. Division of Biology, Kansas State University, Manhattan, Kansas.
- Additional Readings
An order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Asteridae of the class Magnoliopsida (dicotyledons). The order consists of a single family with about 60 species native to tropical America. The plants are herbs with alternate, simple leaves that do not have stipules. The flowers are borne in involucrate heads with centripetal flowering sequence. The calyx is reduced to small lobes or teeth, and the corolla consists of (4)5(6) fused lobes and is regular or somewhat irregular. The stamens are attached near the summit of the corolla tube, and the filaments are more or less connate. The pistil consists of two united carpels, which form a compound, inferior ovary wth a single, pendulous ovule. The order Calycerales is sometimes included within the Dipsacales, and the order has attracted attention because of the overall resemblance of the inflorescence to that of the Asteraceae. See also: Asterales; Asteridae; Dipsacales; Magnoliophyta; Magnoliopsida; Plant kingdom
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