Cetraria. - Synonym. - Iceland Moss. Cetraria islandica (Linne). Acharius (class Lichenes).

Habitat

Northern Hemisphere.

Characters

From 5 to 10 cm. long, foliaceous, irregularly branched into fringed and channelled lobes, brownish above, whitish beneath, and marked with small, depressed spots; brittle and inodorous; when softened in water, cartilaginous, and having a slight odor; its taste is mucilaginous and bitter.

Composition

The chief constituents are - (1) Lichenin, C12H20O10, 70 per cent (2) Cetraric Acid, C18H16O8, a bitter principle, 2 per cent. (3)

Lichenstearic Acid, C14H34O3 1 per cent. (4) Fumaric Acid. (5) Oxalic Acid.

Impurities

Pine leaves, mosses and other lichens.

Preparation

Decoctum Cetrariae. Decoction Of Cetraria

Cetraria, 50. By boiling in water and straining to 1000. Dose, 1 to 4 fl. oz.: 30. to 120. c.c.

Action And Therapeutics Of Iceland Moss

The decoction is demulcent, and may be given in sore throat. The moss is a food, and the jelly formed by boiling may, when suitably flavored, be taken by diabetics.