Fls sessile in compact globose heads, all or mostly 5-merous; cal-lobes very broadly ovate, acute, about equaling the urceolate cor; stigma slender, appearing as a continuation of its style, the two together to about as long as the ovary, included in the eventually calyptrate cor; fr depressed-globose, 2–2.5 mm high and 2.5–3 mm thick, circumscissile near the base; seeds 4, ca 1.2 mm; 2n=42. Native of Europe, parasitic on flax and to be expected in this country wherever flax is grown.