Erect annual or perennial herbs, more or less glabrous. Leaves alternate, entire or minutely toothed, sessile; stipules absent. Inflorescences terminal cymes, usually corymbose. Sepals 5, persistent in fruit; petals 5; stamens 5, alternating with 5 staminodes; ovary usually with 5 fused carpels; ovules 2 per carpel; styles usually 5, free or united for much of their length, stigmas capitate or decurrent along inner side of styles. Capsule subglobose (in Victoria) to ovoid, dehiscing by 10 valves; seeds 10.
About 230 species, distribution as for family; 6 species in Australia (2 native and 4 naturalized).