F. Caroliensis. Swertia Difformis. American Calumba. Nat. Ord. Gentianaceae. Hab. North America.

Med. Prop. and Action. The root (off. U. S. Ph.) is a mild tonic, and bitter, and when cut into slices, closely resembles the true Calumba. From this it may be distinguished by adding Iodine to an aqueous infusion; if it be the true Calumba the infusion turns blue, in consequence of the presence of starch; but no such change takes place with the Frasera. Bigelow§; says that it has considerable tonic powers, and that, when fresh, it is emetic and cathartic.

Therapeutic Uses. The same as those of Gentian and Calumba.