Stems
spotted, much branched, erect 5-30 dm high; basal leaves petiolate the upper
leaves sessile, or nearly so, all pinnately dissected; leaf divisions ovate in
outline - thin, ultimate divisions dentate or incised; petiole dilated and
sheathing at the base; umbels 2.5-7.5 broad; flowers white; fruit 2-2.5 mm long;
ribs prominent when dry; waste places, especially on damp ground.
