Annual or perennial herbs or subshrubs, with milky latex. Stipules 0. Leaves alternate, sometimes mostly basal, very rarely opposite or whorled, usually simple. Inflorescence cymose, racemose or flowers solitary. Bracts present, usually with 2 bracteoles. Flowers bisexual (rarely unisexual), actinomorphic or zygomorphic, sometimes resupinate, usually 5-merous. Sepals fused into a tube. Petals united to varying degrees into a tube, sometimes ± free, sometimes 2-lipped, rarely 1-lipped, often blue. Stamens 5, borne around the base of the style. Ovary ± inferior, rarely superior, (1-)2-10-locular. Style 1. Fruit a capsule (in ours).