This is one of the most poisonous plants native to the United States, and particular attention should be given to establish its identity that it may not be confused with the Sweet Cicely, or Wild Carrot. It has been thought that this species is identical with the one from which the ancient Greeks extracted the poisonous potions that were administered to their political prisoners and others of their day. The great Socrates, it is believed, died from a draught of this poison. The deadly qualities are contained in an aromatic, oily fluid, found chiefly in the roots, but also in every part of the plant. The underground parts are most dangerous, and both men and cattle are poisoned annually through eating its roots, or by drinking water in which its roots may have been crushed. No chemical antidote for this poison is known, and it produces violent deaths. It is a stout, smooth, erect, and slender branching perennial, growing from three to six feet high. The hollow stalk is usually marked with purple lines, and the root has several oblong, fleshy tubers. The compound leaf is twice or thrice divided, and the long pointed, lance-shaped divisions are coarsely and sharply toothed. The veinings seem to end in the notches. The leaves are smooth, dark green, and are set on regular stems. The numerous, insignificant, whitish flowers are loosely arranged in a large, spreading wheel of small, flat-topped umbels. It is found from June to August in swamps and low grounds, from New Mexico and Florida, northward to Minnesota and Manitoba.