A family of herbs, or rarely shrubs or trees, most of which are rough or hispid, usually with rounded stems, and with alternate, exstipulate, entire leaves. The flowers are usually regular and borne in curved cymes. The calyx is 5-toothed, the corolla 5-lobed, saucer-, funnel-, or bell-shaped, and is often pink in bud, changing later to blue. There are 5 stamens, alternating with the corolla-lobes. The ovary is 4-celled, or less often 2-celled, with the style inserted between the 4 lobes, or terminal. The fruit is normally composed of 4 nutlets. There are 156 genera, with about 2500 species, which are cosmopolitan in distribution, but centred in southern Europe and eastern Asia.
Subjects: Plant Sciences and Forestry.