PLANTS: Annual or perennial herbs or small suffrutescent shrubs. STEMS: not twining but sometimes creeping. LEAVES: usually small, ovate to almost linear, entire. INFLORESCENCE: l-several-flowered, axillary, pedunculate cymes. FLOWERS: sessile or on pedicels about as long as calyx; sepals equal; corolla conspicuous, blue, or inconspicuous, faded pale bluish-white, rotate, funnelform to broadly campanulate, the limb plicate, entire, the lobes pilose externally; stamens with filiform filaments, the anthers ovate to oblong or linear; ovary 1-2-locular, 4-ovulate; styles 2, free or partially united at the base, each style deeply bifid for at least half its length into long, terete, filiform to clavate stigmas. FRUITS: globose to ovoid, 4-valved. SEEDS: 1-4, small, smooth or minutely verrucose. NOTES: Ca. 100 American spp.; mostly tropical. (Latin: evolvo = to unroll). Ooststroom, S. J. van. 1934. Meded. Bot. Mus. Herb. Rijksun., Utrecht 14:1-267. REFERENCES: Austin, Daniel F. 1998. J. Ariz. – Nev. Acad. Sci. Convolvulaceae 30(2): 61.