Annual, 1-3 dm, branched from the base, softly villous; lvs cordate-rotund, palmately 3-5-lobed, the lobes incised and sharply toothed; pedicels short and surpassed by
the lvs at first, later elongating; pet 1-3 mm; receptacle glabrous; achenes subrotund, 1.5-3 mm, the margin nearly or quite smooth, the sides with many short, slender, hooked spines from swollen bases; beak flat, triangular, 0.5-1 mm; 2n=14, 28. Native of Europe, found here and there in our range as a weed. Apr.-July.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.