root annual, simple; stem herbaceous, diffusely branched, woolly; leaves oblong, spathulate or nearly linear, sessile, narrowed at base, nigro-mucronate, on both sides woolly; heads homogamous, 12–20-fl., corymboso-paniculate or crowded at the ends of short branches, pedicellate or subsessile; inv. imbricate, the outer scales short, blunt, thinly cobwebby, pale horn-colour, the inner snow-white, opaque, broadly-oblong, very obtuse, glabrous. The largest and strongest of the annual species. Stems 8–18 inches long, sometimes erect and subsimple, sometimes breaking at base into very many diffuse branches. Leaves very variable in comparative length and breadth, the lowest largest. Lower leaves often 1 1/2–2 inches long, 4–6 lines wide; upper 1/2–1 inch long, broad or narrow. Inner inv.-scales remarkably white.
