Lower leaves all acute at base; not glandular nor viscid nor silky-canescent.
Smooth and glabrous, usually glaucous; scales coriaceous at base; leaves firm, usually entire 25–30
Hoary-pubescent or hirsute; scales squarrose; stem-leaves small, linear, entire 31, 32
Scales closely imbricated, not coriaceous at base; branches divaricate; heads many, small 33–35
Remaining species; branches erect or ascending.
Stem-leaves auriculate-clasping or with winged-petiole-like base; involucre lax 42–45
Stem-leaves sessile, but rarely cordate or auriculate at base 36–41
§ 1. HELIÁSTRUM. Pappus simple, coarse and rigid, the stronger bristles somewhat clavate; scales rigid, more or less foliaceous, nearly equal.
1. A. paludòsus, Ait. Stems 1° high; glabrous or nearly so; heads ½´ high, rather few, racemose or spicate; outer scales lax, foliaceous; rays purple; leaves linear, entire.—Mo. to Tex., thence to Car. and Ga.
§ 2. BIÒTIA. Involucre obovoid-bell-shaped; the scales regularly imbricated in several rows, appressed, nearly destitute of herbaceous tips; rays 6–18 (white or nearly so); achenes slender; pappus slightly rigid, simple; lower leaves large, heart-shaped, petioled, coarsely serrate; heads in open corymbs.