Herbs or rarely low shrubs. Leaves opposite, sometimes alternate, rarely whorled, scale-like or succulent, exstipulate, rarely stipulate. Flowers hermaphrodite, solitary or crowded, actinomorphic. Perianth simple, sometimes double with sepals and petals (petaloid staminodes). Calyx tubular or campanulate, often fleshy; sepals 3-5, united or free. Petals (when present) usually numerous. Stamens 3-5 to many, inserted on calyx tube, alternating with sepals. Ovary usually superior, sometimes inferior, 3-5-carpelled, 2- or more-celled, with 1-5 styles and stigmas as many as cells, each cell 1-to many-ovuled; ovules campylotropous or anatropous. Fruit a dry or berry-like, many-seeded capsule. Embryo curved or annular, surrounding the endosperm.