Annual herbs. Leaves alternate, appressed when young. Flowers bisexual, sessile or shortly pedicellate, axillary, often clustered; floral tube narrowly urceolate, persistent; sepals 4, persistent on tube; corolla lobes absent; stamens 8, in 2 alternate whorls, included within floral tube; disc minute or absent; ovary with style terminal, short, stigma capitate or discoid, papillose. Fruit dry.
30 species, found naturally in Europe, northern Africa, and south-western and central Asia; 1 species naturalised in Australia.