Perennial, rarely annual, herbs. Lvs simple, entire, serrate or 1-2-pinnatisect, alternate. Capitula few in corymbs, or often solitary, terminal, pedunculate; involucral bracts in 2-4 rows, at least the inner with membranous margins. Receptacle flat or convex; scales 0. Outer florets usually ♀, ligulate, and white or pinkish, rarely ☿ or ♀, tubular, and yellow; inner florets ☿, tubular. Achenes all similar or somewhat dimorphic, obconic to cylindric or flattened, usually ± evenly 10-ribbed; ribs mostly with mucilaginous cells, and secretory canals between. Pappus a small corona or auricle, sometimes 0.