PLANTS: Annual or perennial herbs, shrubs, or rarely trees, monoecious or dioecious, without latex. LEAVES: alternate, simple; stipules small. INFLORESCENCE: axillary or terminal, spike-like, rarely panicles, staminate, pistillate, or mixed, then most commonly pistillate below and staminate above. STAMINATE FLOWERS: very small, subsessile, several in the axil of a minute bract; calyx lobes 4; petals and disk 0; stamens 4-8, the anthers pendent, elongated, and twisted at maturity. TYPICAL PISTILLATE FLOWERS: sessile, 1-3 in the axil of an often large foliaceous bract; calyx lobes 3(-5); petals and disk 0; pistil with (1-)3 carpels, the ovary (1-)3-locular, the style branches usually dissected into thread-like segments. ALLOMORPHIC PISTILLATE FLOWERS: sometimes present, distal, differing from typical pistillate flowers by having the ovary strongly 1-3 lobed and the style subbasal, and often by being pedicelled and ebracteate. FRUITS: capsules with (1-)3 locules, each segment splitting and falling from the persistent columella; fruits of allomorphic flowers deeply lobed schizocarps. SEED: 1 per carpel, ovoid, usually carunculate, variously sculptured. NOTES: Ca. 400 spp. worldwide, chiefly of tropical and subtropical regions, a few cultivated as ornamentals. (Greek name for stinging nettle, some species resembling nettles, though not stinging). Levin, G. A. 1994. Madroiio 41:254-265. Miller, L. W. 1964. A taxonomic treatment of the species of Acalypha in the United States. Ph.D. dissertation, Purdue University. Pax, F. and K. Hoffmann. 1924. Euphorbiaceae-Crotonoideae-Acalypheae-Acalyphinae. In: A. Engler (ed.). Das Pflanzenreich, IV, 147, XVI(Heft 85):1-231. Radcliffe-Smith, A. 1973. Kew Bulletin 28:525-529. REFERENCES: Levin, Geoffrey A. Euphorbiaceae Part 1. Acalypha and Cnidoscolus. J. Ariz. - Nev. Acad. Sci. 29(1): 18.