Aromatic perennial, often rhizomatous herbs; branches quadrangular; hairs simple or rarely branched, glands sessile. Leaves opposite, petiolate or sessile, simple; margin serrate or entire. Inflorescence of pseudowhorls formed by several few-many-flowered cymes crowded in axils of upper leaves or bracts. Calyx 5-lobed, lobes c. equal; corolla slightly 2-lipped or 4-lobed, then abaxial lip with 3 subequal lobes and adaxial lobe truncate, emarginate or 2-lobed; stamens 4, fertile, inserted below the throat of the corolla-tube, filaments erect, anthers with 2 fertile locules, not diverging. Mericarps not keeled.
About 25 species, mostly from the Northern Hemisphere and southern Africa; 6 species native and 5 naturalised in Australia.