Sponge. Spongia. Spongia officinalis. Eponge, Fr. Schwamm. Badeschwamin, G.—The sponge is "a flexible, fixed, torpid, polymorphous animal, composed either of reticular fibers or masses of small spires interwoven together, and clothed with a gelatinous flesh, full of small mouths on its surface, by which it absorbs and ejects water." Until recently sponges were classified as colonial Protozoa, the lowest group of animals, but they are now brought under a separate phylum known as Porifera (or Spongiaria) a name applied to them because of their abundance of water pores. The latter are of two kinds, both opening into the digestive canals and ramifying passages of the sponge. Some of these are large, but most of them are small, being in the nature of inhalant pores or inlets for admitting the water. The current through these pores is a constant one which is induced by countless flagella which occur in definite enlargements on the canals and known as ciliated chambers. This current contains the minute organisms which are carried to the digestive cavities and upon which the animal feeds. Through these canals oxygen is distributed, the waste matters eliminated and fertilization of the eggs is effected. Sponges inhabit the bottom of the sea, where they are fixed to rocks or other solid bodies, and are most abundant within the tropics. They are collected chiefly in the Mediterranean and Red Seas, the West Indies and the coast of Florida and Central America. In the Grecian Archipelago, Crete, Cyprus, on the coast of Asia Minor, Syria, Barbary and the Bahama Islands, sponge fisheries constitute a very important industry. Formerly most of the sponges used in the United States were brought from the Mediterranean waters, but since 1852 the Bahamas and the coast of Florida have furnished much of the commercial supply. When collected they are enveloped in a gelatinous coating, which forms part of the animal. For details of fishery and preparation, see P. J., xx. Large quantities .of the coarser kinds are imported from the Bahamas, but the finest and most esteemed are brought from the Mediterranean, especially from the coast of Syria. Recently the cultivation of sponges has been undertaken on an extensive scale. Small fragments are cut under water from the live sponge, and fixed upon a sandy bottom by means of skewers. In three years they will have grown sufficiently to be marketable.
Sponge, as found in commerce, is in yellowish-brown masses of various shapes and sizes, light, porous, elastic, and composed of fine, flexible, tenacious fibers, interwoven in the form of cells and meshes. It usually contains numerous minute fragments of coral or stone, or small shells, from which it must be freed before it can be used for ordinary purposes. Sponge is prepared by macerating it for several days in cold water, beating it in order to break up the concretions which it contains, and dissolving what cannot thus be separated of the calcareous matter by hydrochloric acid diluted with thirty parts of water. By this process it is rendered perfectly soft, and fit for surgical use. It may be bleached by steeping it in water impregnated with sulphurous acid, or by exposure in a moist state to the action of chlorine. It is stated that sponges which have been soaked in pus and infectious matters will recover their primitive condition by soaking in a 4 per cent. solution of potassium permanganate, then in a 25 per cent. solution of official sulphurous acid, and finally thorough washing in an abundance of water. (A. J. P., xliv, 355.) When intended for surgical purposes, the softest, finest, and most elastic sponges should be selected; for forming burnt sponge the coarser will answer equally well. According to Hatchett, the chemical constituents of sponge are gelatin, coagulated albumin, common salt, and calcium carbonate. Magnesia, silica, iron, sulphur, and phosphorus have been detected in it, as also iodine and bromine, combined with sodium and potassium. From the experiments of Croockewit, it would appear that sponge is closely analogous to, if not identical with, the fibroin and sericin of silk, differing from it only in containing iodine, sulphur, and phosphorus. (Ann. Ch. Ph., xlviii, 43.) Schlossberger, however, has shown that it is distinct, in its very slight solubility in ammoniacal solution of copper hydroxide and in its yielding leucine and glycocoll when treated with diluted sulphuric acid, while sericin yields under similar treatment tyrosine and serin. He names the principle spongin.
Sponges are used for mechanical purposes only. Sponge tent is employed for dilating sinuses. This is prepared by dipping sponge into melted wax, compressing it between two flat surfaces till the wax hardens, and then cutting it into pieces of a proper form and size. By the heat of the body the wax becomes soft, and the sponge, expanding by the imbibition of moisture, gradually dilates the wound or sinus in which it may be placed. When a conical sponge tent of uniform caliber is required, as for dilating the uterine cavity, a better plan is to cut the sponge into a conical shape while fresh and compress when moist, by winding it carefully with a fine tightly drawn cord, removing the cord when perfectly dry, and dipping the tent into melted wax, so as to get a thick coating. For other modes of preparing sponge tent, as well as of saturating the sponge at the same time with substances calculated to make a, remedial impression, as phenol, alum, lead acetate, etc., see A. J. P., 1868, 410; 1869, 446.
Spongia Usta, Burnt Sponge, was formerly official (Spongia Usta, U. S. 1850), but is no longer used in medicine. For method of preparation, analysis, and therapeutic properties, see 16th edition, U. S. D.
The Dispensatory of the United States of America, 1918, was edited by Joseph P. Remington, Horatio C. Wood and others.