Tufted, sometimes rhizomatous, annual or perennial herbs. Roots fibrous to tuberous. Leaves basal, linear, angular or terete. Inflorescence a bracteate raceme or racemose panicle; pedicels articulate; flowers bisexual, perianth segments equal, spreading, free or shortly fused at base, 1-nerved; stamens 6, anthers dorsifixed; ovary superior, trilocular, ovules 2 per locule; style filiform, stigma 3-lobed. Fruit a loculicidally dehiscent capsule; seeds triquetrous, black.
About 12 species, from the Mediterranean and Asia Minor to India; 1 naturalised in Australia.