Annual or perennial herbs, with stems usually trailing or climbing. Lvs mostly alternate, sometimes the lower opposite; lamina broad, partly palmately and partly pinnately veined, often hastate or sagittate. Fls usually axillary and solitary, rarely in axillary or terminal racemes. Calyx with 5 subequal lobes. Corolla with cylindric tube forming a spur at base; limb 2-lipped; upper lip 2-lobed; lower lip 3-lobed and with pouch at base closing throat (mouth of tube). Stamens 4, included. Capsule ± globose; loculi equal, each opening by a pore or detachable lip. Seeds numerous, pitted or tuberculate, small; wing 0.