Annual or perennial herbs or subshrubs. Leaves toothed or ternately divided. Inflorescence a simple umbel, surrounded by a radiating involucre of white to slightly coloured, often woolly to tomentose bracts; outer flowers often male, inner flowers bisexual and/or female. Sepals lobed or truncate; petals spathulate or orbicular, or absent; nectary often not quite at base of style; fruit ovate, compressed, 5-ribbed; carpophore absent.
15 species: 14 in Australia and 1 in New Zealand.