The root-stock is slender, the stem also slender, round, striate, 9 inches to 3 feet high. The root-leaves are numerous, shortly stalked, pinnate, the leaflets oval or roundish, four to eight pairs, sometimes so deeply cut as to be bipinnate, sometimes merely serrated. The stem-leaves are few, with the petiole dilated, particularly in the uppermost ones, the leaflets narrower than in the radical leaves, and pinnatifid. The upper leaves are reduced to dilated sheaths, the leaflets represented by one or more linear lobes. The umbels are regular, flattopped, the umbelules many-flowered, the individual flowers 1/10 inch across, white, with notched petals. The whole plant is dark green, generally glabrous.