AL′GÆ

(ăl′-jē). [L. pl.] Syn. Al′gals ; Algæ (DC.), Al′gales (Lindl.), L.; Algues , Varech , Fr.; Alge , Meer gra , See gra , Ger. Sea-weeds. In botany , an order of Thallogens living in water or very moist places, nourished throughout their whole surface by the medium in which they live, having no distinct axis of vegetation, and propagated by zoöspores, coloured spores, or tetraspores. Linnæus defines them—“plants, the roots, leaves, and stems of which are all in one.” The algæ consist either of simple vesicles lying in mucus, or of articulated filaments, or of lobed fronds formed of uniform cellular ti ue. Those that vegetate in salt water are popularly called SEA-WEEDS (fu′ci, L.) and LA′VER (ulvæ, L.); those found in fresh water CONFER′VÆ . One of their divisions (the Zoöspermeæ ) comprehends the lowest known forms of vegetable life, being merely adhering cells, emitting, at maturity, seeds or sporules having a distinct animal motion. In Oscillator i as , the whole plant twists and writhes spontaneously; and Zymenas actually copulate like animals. Some of the Algæ po e great beauty. In the lower grades the colour is green; in the higher, red or purple. Prop., Uses, . None of the Algæ are poisonous. Several are nutritious, emollient, and demulcent, from containing mucilage (carrageenin), starch, sugar (mannite), and a little albumen; and are hence used as esculents. The ash from the dried weed varies in different varieties from 9% to fully 25%; and contains variable quantities of pota a, soda, lime, magnesia, iron, manganese, and silica, with sulphuric acid, phosphoric acid, chlorine, and a little iodine and bromine. (Schweitzer; Forchhammer; Gödechens.) Sea-weeds, their charcoal, and their ashes, have been long regarded as alterative and resolvent; and anti-phthisic virtues have been attributed to them by Laennec and others. They were formerly much given in scrofulous affections and glandular enlargements; but their use is now almost superseded by that of iodine and its preparations. Dr Sten house has proposed some of the algæ as furnishing an economical source of mannite. The sea algæ are used for manure; their ashes form KELP . The following table, showing the results of several analyses of different kinds of algæ, and illustrating the very large amount of nitrogen contained in them, is from Mr Walter Blyth’s excellent dictionary of ‘Hygiene and Public Health.’ | Kinds of Algæ. | Water. | Dry matter. | Per cent. Nitrogen in dry matter. | Protein contained in dry matter. | | Chondrus crisp us, bleached, from Bewlay Evans. | 17·92 | 82·08 | 1·534 | 9·587 | | Chondrus crisp us, unbleached, Bally castle. | 21·47 | 78·53 | 2·142 | 13·387 | | Gigastina mamillosa, Bally castle. | 21·55 | 78·45 | 2·198 | 13·737 | | Chondrus crisp us, bleached, second experiment. | 19·79 | 80·21 | 1·485 | 9·281 | | Chondrus crisp us, unbleached second experiment. | 19·96 | 80·04 | 2·510 | 15·687 | | Laminaria digit at a, or dulse tangle. | 21·38 | 78·62 | 1·588 | 9·925 | | Rhodomenia palmata. | 16·56 | 83·44 | 3·465 | 21·656 | | Porphyra lac in i at a. | 17·41 | 82·59 | 4·650 | 29·062 | | Iridæa edulis. | 19·61 | 80·39 | 3·088 | 19·300 | | Alaria esculent a. | 17·91 | 80·09 | 2·424 | 15·150 | From the above, we learn the important fact that the sea-weeds found on our coasts are amongst the most nutritious of vegetable substances, and that they, when dry, are even richer in nitrogenous matter than either oatmeal or Indian corn in the same state. The following are the chief varieties of algæ which are used as food by the dwellers on our coasts as well as on the continent:— Porphyra lac in i at a and VULGAR IS , called laver in England, stoke in Ireland, and slouk in Scotland. Chondrus crisp us , called carrageen or Irish mo , and also pearl-mo , and sea-mo . Laminaria digit at a , known as the sea-girdle in England, tangle in Scotland, and red-ware in the Orkneys; and Laminaria saccharin a , Alaria esculent a , or bladder-lock , called also henware , and honey-ware by the Scotch. Ulva lati ima or Green Laver — Rhodomenia palmata or dulse of Scotland. Under the name of “marine sauce” the Laver was esteemed a luxury in London, where it may now occasionally be met with in the shops of provision merchants. The employment of the Chondrus crisp us or Carrageen in the form of an aliment for consumptive and weakly persons, would seem from the analysis of it given above to be fully justified. In preparing the algæ for food, they must be soaked in water to remove the saline matter, and where they are po e ed of a bitter flavour this may be removed by adding a little carbonate of soda to the water. They should then be stewed in water or milk till they are tender. The best flavourings are pepper and vinegar. See Jelly .