Heads radiate, the rays mostly ca 13(21), neutral or with a vestigial style, often drooping, our spp. purple to white; invol bracts in 2–4 subequal or slightly imbricate series, with firm base and spreading or reflexed green tip, the inner sometimes passing into those of the receptacle, but not sharply divisible into 2 types; receptacle conic, its bracts partly enfolding the achenes, firm, with stout, spinescent tip conspicuously exceeding the disk-cor; disk-cors slightly bulbous-thickened at base, not narrowed to a slender tube; style-branches flattened, without well marked stigmatic lines, and with slender, acuminate, hairy appendage; achenes quadrangular, glabrous or sparsely hairy on the angles; pappus a short, toothed crown; perennial herbs with simple, alternate, entire or toothed, mostly trinerved lvs and solitary or few, mostly long-pedunculate heads. 5, U.S. and adj. Can. (Brauneria)
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