Plants annual or perennial herbs (shrubs or small trees elsewhere), unarmed. Stems erect or strongly ascending, often relatively stout, unbranched or with few to several ascending branches, mostly toward the tip, sparsely to densely glandular-hairy (the plants somewhat sticky to the touch). Leaves alternate and sometimes also basal, sessile to long-petiolate. Leaf blades simple, variously shaped, unlobed or with a pair of basal auricles, the margins entire or at most wavy, the surfaces glandular-hairy and sometimes also with sessile glands. Inflorescences terminal, panicles or racemes. Flowers ascending and/or spreading, the fruits usually more or less ascending. Calyces 8–20 cm long, unequally 5-lobed, broadly tubular to bell-shaped at flowering, rounded at the base, lacking basal auricles, the sides rounded or more commonly more or less 5- or 10-ridged, persistent intact but often slightly enlarged and distended at fruiting. Corollas 1.5–11.0 cm long, trumpet-shaped to somewhat funnelform, relatively shallowly 5-lobed, the lobes variously shaped, often appearing spirally twisted and pleated in bud, variously colored. Stamens with filaments longer than the anthers, unequal in length and/or attachment point in the corolla tube (usually 1 filament longer than and/or attached below the other 4), the anthers free, erect or incurved, not exserted, dehiscent longitudinally, light yellow to nearly white. Ovary 2-carpellate the style elongate, positioned at or slightly above the level of the anthers, often green. Fruits capsules, dry, globose to ovoid or ellipsoid, 2-locular, tan or light brown, dehiscent longitudinally from the tip, with numerous seeds, unarmed. Seeds 0.4–1.1 mm in longest dimension, more or less circular ro broadly elliptic, oval, or angular, flattened, the surface with a fine network of ridges or appearing finely wrinkled, light to dark brown, lacking wings. About 76 species, North America, Central America, South America, Africa, Australia.