Mostly lactiferous shrub, sometimes trees. Stem usually fistular. Leaves alternate or spiral, mostly clustered at the tip of branches, penni-nerved, usually glandular in the axils, petioled or subsessile. Inflorescence of axillary or terminal dichotomous cymes, corymbose or thyrsiform. Flowers large and showy with large deciduous bracts. Calyx 5-lobed, glandular outside, eglandular inside, lobes equal or subequal. Corolla salverform or funnel-shaped, lobes 5, spreading, contorted in bud, thick with cylindrical tube, appendages absent, throat naked. Stamens 5, included, attached near the base of corolla tube, free from stigma, without enlarged connective. Disc absent or present fleshy, usually covering the calyx tube. Ovary subsuperior; ovules multiseriate; style 1 with a bicapitate slender stigma. Follicles linear-oblong, seeds numerous, with large irregular wing.