PLANTS: Herbs, shrubs, or trees, monoecious, with milky latex, armed with stinging hairs. LEAVES: alternate, simple, palmately veined and often palmately deeply lobed, stipulate; petioles glandular at the junction with the blade. INFLORESCENCE: terminal cymes. STAMINATE FLOWERS: toward the outside of the cyme; calyx 5-lobed, petal-like, white; petals 0; disk ring-shaped; stamens 8-10 in two whorls, the outer free and the inner connate or all connate; staminodes sometimes borne at the apex of the staminal column. PISTILLATE FLOWERS: toward the center of the cyme; sepals 5, separate, petal-like, white, falling soon after flowering; petals 0; disk ring-shaped, sometimes with staminodes; pistil with 3 carpels, the ovary 3-locular, the styles branching dichotomously several times. FRUIT: a capsule with 3 locules, each segment splitting and falling from the persistent columella. SEEDS: 1 per carpel, carunculate. NOTES: Ca. 50 spp. of subtropical and tropical Amer. (Greek: Cnide = nettle + skolos = thorn, in reference to the stinging hairs). REFERENCES: Levin, Geoffrey A. Euphorbiaceae. Part 1. Acalypha and Cnidoscolus. J. Ariz. – Nev. Acad. Sci. 29(1): 18.