Description from
Flora of China
Trees or shrubs with milky latex. Leaves opposite. Cymes terminal or axillary, many flowered. Calyx small, glandular inside at base, glands alternating with lobes. Corolla salverform, tube cylindric, slightly inflated near base, lobes overlapping to right. Stamens inserted near base of corolla tube; filaments short; anthers narrowly ovate, free from pistil head, lobes rounded at base; disc absent. Ovaries 2, distinct; ovules numerous on each placenta. Style short. Follicles 2, distinct, cylindric, dehiscent. Seeds numerous, linear, with coma at 1 end; endosperm scanty.
Four species: tropical Africa, SE Asia; one species in China.