An order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Dilleniidae of the class Magnoliopsida (dicotyledons). The order consists of three families: the Myrsinaceae, with about 1000 species; the Primulaceae, with about 1000 species; and the Theophrastaceae, with a little more than 100 species. These are plants with sympetalous flowers; that is, the petals are fused by their margins to form a corolla with a basal tube and terminal lobes. The functional stamens are opposite the corolla lobes, and there is a compound ovary that has a single style and two to numerous ovules which usually have two integuments and are on a free-central or basal placenta. The Myrsinaceae and Theophrastaceae are chiefly tropical and subtropical woody plants, but the Primulaceae are mostly herbaceous and are best developed in north temperate regions. Primrose (Primula) and cyclamen are familiar members of the Primulaceae.