Wild orange Tree, to 20 m tall and 55 cm dbh, weakly buttressed, sometimes involuted, usually glabrous; bark with small vertical rows of lenticels; wood hard, heavy; sap milky, copious. Leaves opposite; petioles 2-11 mm long, with a prominent interpetiolar ridge (leaving a prominent scar), glandular in axils; blades mostly elliptic to obovate, short-acuminate, obtuse to acute at base, 5-18 cm long, 2.5-6 cm wide, dotted with brown glands below. Corymbs terminal; pedicels to 1 em long; bracteoles 1.5-2 mm long; flowers fragrant, many, 5-parted; calyx lobes ovate, 1.5-3 mm long, each with several slender squamellae inside at base; corolla white, the limb ca 2 cm wide, the tube to 9 mm long, swollen in basal half, pubescent inside above the point of staminal attachment; stamens included, attached just above base of tube; anthers ca 3.2 mm long, free; style and stigma 1, 5-lobed, ca 2 mm long; nectaries lacking. Follicles 2, reniform, to 7.3 cm long and 5 cm wide; exocarp roughened, splitting at maturity to expose orange matrix and brown seeds; seeds oblong, many, to 13 mm long, longitudinally striate. Croat 5242, 5419. Common in and mostly restricted to the older forest. Flowers mainly from March to June. Flowering time and intensity may vary from year to year. R. Foster (pers. comm.) reports that in one year trees flowered synchronously and heavily over a few weeks, but that in the next year there was intermittent flowering over several months. Time of fruit maturity is uncertain, possibly during the dry season (January to March). The fruits are eaten by white-faced monkeys in June (J. Oppenheimer, pers. comm.).