Alstonia

Tall glabrous trees. Leaves in whorls of 3-6, more rarely opposite, with more than 25 pairs of lateral veins; stipules absent, but usually with many small colleters in a fringe or covering hollowed base of petiole. Flowers relatively small, usually in many-flowered, compound, terminal, umbelliform, corymbose or panicled inflorescences. Calyx small, divided almost to base; segments broadly ovate. Corolla salver-shaped; tube slender, cylindric, sparsely pubescent within, villous at mouth; lobes somewhat obliquely ovate, contorted, overlapping to right. Stamens in widened part of corolla tube; filaments filiform, short; anthers free from stigma, 2-lobed at base, polliniferous to base. Disc absent or obscurely annular. Ovary of 2 free carpels; style filiform, short; stigma with a ring of reflexed frills at base. Mericarps 2, follicular, cylindric, slender. Seeds oblong, compressed, with hairs all around edges, but chiefly at both ends.