Laminaria.—Laminaria.

Related entries: Fucus

The sea weed Laminaria Cloustoni, Edmonston (L. digitata, Lamouroux).
Nat. Ord.—Algae.
COMMON NAMES: Sea tangles, Sea girdles.

Botanical Source and History.—This marine plant, together with another, the Laminaria flexicaulis, Le Jolis (Laminaria stenophylla, Harvey., were included by Linnaeus under the name Fucus digitatus. The last has a deep-brown, flexible, shining stem, and, when dry, becomes thin and fibre-like. The Laminaria Cloustoni is not flexible, but rigid and erect, its stem being cylindrical and from 3 to 6 feet long and 2 inches thick at the base. In color it is light-brown. Below the stem it divides into root-like branches, which spread and attach the plant to the submarine rocks. The frond is flat, coriaceous, of an olive-green color, and divided into finger-like divisions. The cylindrical part of the stem only is used. The plants grow upon the rocks in the Atlantic, Pacific, and Arctic Oceans.

Description and Chemical Composition.—Laminaria, in commerce, consists of dried, cylindrical portions of the stem, somewhat irregular, deeply corrugated, a half inch or less in thickness, horny in consistence, of great strength and elasticity, and breaking with a smooth, corneous fracture. The color is brown, the internal portion being paler than the outer. Its value depends upon its property of softening and swelling to several times its diameter when immersed in water, and when in contact with the secretions of the body. A whiter, inner layer is composed of large cells, while smaller cells occupy the outer, brownish portion. Large, elongated, mucilage cells are also present. When formed into conical and cylindrical sticks they are ready for use. Mannit was found in the plant by Stenhouse. Dextrose is likewise present. It contains an abundance of mucilage, from which Schmiedeberg (1885) isolated laminaric acid, a substance having the property of swelling up with water to an unusual degree, and laminarin, an indifferent mucilage; and the mineral constituents common to marine plants (see Chondrus). The ash of this class of algae (Laminaria) amounts to about 14 per cent, and the species, L. digitata, is the chief source of the production of iodine on the Norwegian coast, containing about 1 per cent of this element (Jensen, Jahresb. der Pharm., 1888, p. 155). Laminaria, when distilled with sulphuric acid and water, yields a liquid (fucusol) containing furfurol (furfuraldehyde, C4H3.CHO) and derivatives (Flückiger, Pharmacognosie, 1891, p. 279).

Action and Uses.—Laminaria was brought forward as a substitute for sponge tents for the dilatation of such parts as the uterine os, urethra, etc. Being of smaller size, and of greater rigidity, they are more easily introduced into small apertures and tortuous canals than sponge tents, while, on the other hand, their very rigidity renders them more liable to produce hemorrhage when organic changes occur in the uterus, or when such growths as polypi occlude the os. They readily swell to four times their diameter by the ease with which they absorb fluids, and do not so retain the discharges as to induce putrefactive changes. If greater dilatation is desired than is produced by a single tent, several may be fastened together. Sea tangle tents are considered less eligible than the rubber bag, or the sponge tents, for inducing premature births.

Related Plants and Preparations.Laminaria esculenta, Lamouroux, as well as the Laminaria saccharina, Lamouroux, which has entire fronds and a flattish stem, and when washed with water becomes sweet, are edible. They likewise yield iodine.

Several pharmaceutical preparations from various species of laminaria and related algae, were suggested by Mr. James Wheeler (see Amer. Jour. Pharm., 1882, p. 124).

TUPELO.—On account of the greater ease with which absorption of fluids and consequent swelling of tissues take place, the root-wood of two species of Nyssa has been used for tents and bougies instead of laminaria. The tissue is light, spongy, and white, and, when in contact with fluid, doubles in thickness. This root-wood is known as Tupelo, from the trees (of Nat. Ord.—Cornaceae) which yield it, the species being the Nyssa grandidentata, Michaux filius, the Cotton-gum, or Large tupelo; and the Nyssa capitata, Walter, the Sour-gum, Tupelo-gum, or Ogechee lime. They grow near the coast in the southern states.


King's American Dispensatory, 1898, was written by Harvey Wickes Felter, M.D., and John Uri Lloyd, Phr. M., Ph. D.