rarely shrubs. Leaves simple, generally whorled, obovate, oblong or lanceolate,
entire, glabrous. Inflorescence paniculate or corymbose, terminal cymes.
Flowers saver-shaped. Calyx 5-lobed, without scales or glands. Corolla 5-lobed
with cylindrical tube, hairy only at the mouth, white or greenish-white.
Stamens inserted in the corolla tube. Ovary of 2 distinct carpels, united by
the style; stigma short or 2-toothed, ovules numerous. Follicles 2,
cylindrical. Seeds many, oblong or linear, usually hairy.