Mostly perennials (very rarely annuals), sometimes biennial herbs, forming mats from rootstock, or erect. Leaves basal as well as cauline, basal forming rosettes, conspicuosly larger than cauline leaves, uni-nerved, linear-lanceolate or ovate, cauline laxly-densely arranged, sometimes imbricate, opposite. Inflorescence usually single-few flowered umbels, usually simple or racemose cymes. Flowers actinomorphic, bisexual, pentamerous. Calyx divided to various lengths, lobes linear, lanceolate or ovate, unequal or equal, often scabrously margined. Corolla tubular, infundibular or hypocraetiform, in shades of blue, purple, violet, red, pink, white, yellow, divided, provided with subsidiary lobes or plicae, plicae smaller than and alternating with corolla lobes, naked inside i.e. not provided with ciliae or fimbriae. Stamens corresponding the number of and alternating with corolla lobes and opposite the plicae, anthers dorsifixed or versatile with filaments inserted in the middle in the lower portion of the corolla tube. Ovary superior, unilocular, placentation parietal, with numerous ovules, stigmas 2, coiled at apex, mostly with a style or sessile. Nectaries present at the base of the ovary. Capsule elliptic-oblong, large or short stalked or sessile, dehiscing septicidally from apex. Seeds light-dark brown, ellipsoidal, ovate or rounded, reticulate.