"Flowers in close heads (the compound flower of the older botanists), upon a common receptacle, surrounded by an involucre, with 5 (rarely 4) stamens inserted on the corolla, their anthers united in a tube (syngenesious).  Calyx-tube united with the one-celled ovary, the limb (pappus) crowning its summit in the form of bristles, awns, scales, and teeth, or cup-shaped, or else entirely absent.  Corolla either strap-shaped or tubular; in the latter chiefly 5-lobed, valvate the bud, the veins bordering the margins of the lobes.  Style 2-cleft at the apex.  Fruit seed-like (achenium), dry, containing a single erect anatropous seed, with no albumen."