S. arvensis: annual; stems decumbent, branched, seldom over six inches high; leaves about six in a whorl, the lower ones obovate, the upper linear or lanceolate, acute, rough-edged; flowers small, blue or pink, in little terminal heads, surrounded by a broad, leafy, eight-lobed involucre; calyx-teeth enlarged after flowering, forming a little leafy crown at the top of the fruit. - Cultivated and waste places. Fl. June to August.