Shrubby or climbing perennials; roots fibrous. Leaves spirally arranged, separated by distinct internodes, stem-sheathing, linear-lanceolate, thin, flat; margins dentate, usually spiny. Inflorescence axillary, racemose, subspicate, or capitate, usually unbranched. Flowers bisexual, subtended by bracts, slightly zygomorphic, pedicellate; perianth segments in two series, usually united; stamens 6, exserted or included; style filiform, exceeding anthers, stigma usually capitate. Fruit a loculicidal capsule; seeds triquetrous to flattened, sometimes winged.
10 species in South Africa, widely cultivated; 1 naturalised in Australia.
