Chondrus crispus, (Linne) Stackhouse,
Gigartina mamillosa, (Goodenough et Woodward) Agardh.
The dried plants.
Habitat. North Atlantic Ocean, New England, Irish Coast.
Syn. Irish Moss, Carrag(h)een, Carragreen (Moss), Killeen, Pearl Moss, Pig-wrack, Salt Rock Moss, Fucus Crispus; Fr. Carragaheen, Mousse (Marine) perlee; Ger. Carrageen, Irlandisches Moos, Perl Moos, Knorpeltang.
Chon'drus. L. fr. Gr.
cartilage, gristle - i. e., fronds are cartilaginous. Cris'pus. L. curled, crumpled - i. e., its physical appearance. Gig-ar-ti'na. L. see etymology, above, of Gigartinaceae. Ma-mil-lo'sa. L. mamillosus, breasted, filled with papillae or breasts - i. e., from resemblance of the spores on the surface and margins of the fronds.
Plants. - Entire, more or less matted together, consisting of slender stalk branching dichotomously, segments flattened, emarginate or deeply cleft at tips, 5-15 Cm. (2-60 long, 1-10 Mm. 1/25-2/5') broad, yellowish-white, translucent, frequently coated with a calcareous deposit effervescing with hydrochloric acid, sometimes sporangia
(53) embedded near apex of segments (C. crispus) or on short stalks scattered over upper portion of segments (G. mamillosa), somewhat cartilaginous; odor slight, seaweed-like; taste mucilaginous, saline. Tests: 1. Boil for 10 minutes 1 part with water (30), replacing evaporation - strained liquid forms thick jelly upon cooling. 2. Soft, gelatinous, and transparent with cold water; boil .3 Gm. in 100 Ml. (Cc.) of water, filtrate + tannic acid T. S. - no precipitate (abs. of gelatin); when cold + iodine T. S. - no blue (abs. of starch). Solvent: water. Dose, 3j-2 (4-8 Gm.).
Fig. 1. - Chondrus crispus: a, narrow form, with fruit; b, broad form; c, small form.
Adulterations. - Allied plants, especially Gigartina acicularis and G. pistillata, which resemble the official very closely.
Commercial. - Plants, commonly known as seaweed or bladder-wrack, grow attached by a small disk to submerged rocks, and, unless bleached, are greenish (fresh) or purplish (dry). Although the spring crop is superior (that of summer often being attacked by black mildew), yet most is collected, June-August, on the coasts of Ireland and Massachusetts, by boatmen tearing it from rocks, 3-6 M. (10-20°) under water, with rakes, hooks and tongs, or some is taken directly from the beach where left by storms and tides; it is then washed in seawater and spread high upon the shore for one or more weeks to become partly bleached by sun and dew, and afterward put into hogsheads, rolled in marshes until saturated with seawater (avoiding fresh water) and spread out on land, a dual treatment repeated several times to obtain the desired yellowish-white color; finally it is dried in barns and packed in barrels (100 pounds; 45 Kg.).
Constituents. - Mucilage 55-90 p. c, Minerals 14 p. c, albuminoids 9 p. c, water 18 p. c, cellulose 2 p. c, ash 8-15 p. c.
Fig. 2. - Gigartina mamillosa: a, narrow form, with fruit; b, large form; c, small form.
Fig. 3. - Fucus vesiculosus: fruiting branch, natural size.
Mucilage. - A kind of pectin called carrageenin, 9 p. c. of which is soluble in cold, nearly all in hot water; it differs from gum by alcohol not precipitating the aqueous solution, from starch by not turning blue with iodine, from pectin by not precipitating with lead acetate, and yielding no mucic acid with nitric acid; with diluted sulphuric acid yields galactose (sugar); has only slight adhesive properties, but sometimes is substituted in its three forms, white, yellowish, yellow, for acacia, under the name of "imitation gum arabic."
Preparations. - (Unoff.): Decoction, 5 p. c. (water or milk), dose, ℥j - 2 (30-60 Ml. (Cc.)). Mucilage, 3 p. c, mostly as an emulsifier. Gelatin. Any of these may be sweetened and flavored with lemon juice, etc., to one's pleasure. By macerating 10 minutes in cold water, throwing liquid away, then boiling with fresh water for 15 minutes, we get a solution free from any unpleasant flavor of saline or other foreign substances.
Properties. - Demulcent, nutrient, dietetic.
Uses. - Bronchitis, dysentery, diarrhoea, kidney and bladder affections, scrofula. Sheet gelatin is substituted for poultices by wrapping in flannel and moistening; may also be used as a diet wherever tapioca, sago, or barley is desired.
1. Agar. Agar, official. - (Syn., Agar-agar, Jelly Plant, Corsican (Worm) Moss, Crow-silk, Japanese (Chinese, Bengal, Ceylon) Isinglass, Gelatin; Fr. Mouse de Corse; Ger. Wurmmoss, Wurmtang). The dried mucilaginous substance extracted from Gracila'ria (Sphoe-rococ'cus) lichenoi'des, Greville, + other marine algae (Gelid'ium, Gloiopel'tis species) growing along the eastern coast of Asia.
Manufacture: Algae are spread out, May-August, on the ground in thin layer, sprinkled repeatedly with water, kneaded by hands and feet, placed in baskets, washed thoroughly by immersion in water, spread out evenly in thin layer on straw, rush mats, shallow trays to bleach and dry. Agar, mostly in bundles, .4-.6 M. (16-24') long, consisting of thin, translucent, membranous, agglutinated pieces, 4-8 Mm. (1/6 - 1/3') broad, yellowish-brownish-white, shiny, tough (damp), brittle (dry); odor slight; taste mucilaginous, insoluble in water, slowly soluble in hot water. Powder, pale buff; microscopically - transparent granular fragments (occasionally frustules of diatoms) with iodine T. S. - bright red + bluish-black areas. Tests: 1. Solution in hot water (1 in 100) - stiff jelly upon cooling; incinerate - ash 5 p. c. 2. Hot aqueous solution (.1 in 100) upon cooling, + tannic acid T. S. - no precipitate (abs. of gelatin); + iodine T. S. - not blue (abs. of starch). Impurities: Foreign frustules, gelatin, starch, etc.
Properties and Uses. - Demulcent, emulsifyer; chiefly to form a solid medium (culture media) for artificial cultivation of bacteria and other organisms; soups, etc.; poor substitute for sodium stearate in suppositories, as it absorbs only 70 p. c. of glycerin, and melts at higher than body temperature. Native "Kanten" and "Fenori," are also from related algae, being used to impart gloss to textiles, silk, stiffening linen (starch), decorating china, plastering walls, sizing, glue, etc.; granular form recommended as an aperient (3j; 4 Gm.).
1. Gigartina acicula'ris and G. pistilla'ta. - Both have appearance and properties similar to the official.