Annual herbs. Leaves opposite below, narrow, margins entire, subsessile. Flowers in terminal bracteate racemes. Sepals unequal, longer than corolla-tube; corolla 2-lipped, tube swollen at base into a pouch on the lower side, upper lip 2-lobed, lower lip 3-lobed, with a prominent palate at base closing the mouth; stamens 4, in pairs of unequal length; stigma capitate. Capsule with 2 unequal locules, the narrower upper loculus opening by a single apical pore, the lower by 2 pores; seeds many, flat but thick, with one face smooth, narrowly winged, the other with a thick undulate minutely papillose rim, surrounding a hollow sometimes with a central ridge or row of a few tubercles.
3 species, probably all from the Mediterranean region; 1 species naturalised in Australia.
Antirrhinum, the genus of commonly cultivated snapdragons, differs by its perennial habit, more or less equal sepals, and wrinkled-reticulate seeds.