SPONGIA 441 



OTHER SPECIES. Besides S. officinalis, which is next to S. medicinalis in 

 importance and is similar in appearance (only there are no spots, and a black 

 line extends along each side), may be mentioned Hirudo provincialis, H. 

 obscura, and H. interrupta, the species common in this country being known 

 as H. decora. Leeches are said to be found in great abundance throughout 

 India. 



PRESERVATION. The usual way of keeping leeches is to place them in clear 

 water, in a shaded spot if possible, where the temperature will range from 

 10 to 2OC. (50 to 68F.), care being taken to have a considerable quantity 

 of charcoal, moss, and pebbles in the containing vessel. 



USE. For local blood-letting, a single leech being able to extract from I to 

 2 drachms of blood. 



SPECIAL ANIMAL TISSUES AND SECRETIONS 



609. SPONGIA. SPONGE. Spon'gia officina'lis Linne\ Class, Porifera; order, 

 Ceratospongiae. 



HABITAT. Red Sea, Mediterranean Sea, Atlantic Ocean, and other bodies 

 of salt water, upon the rocky bottom. 



COLLECTION. The best sponges are secured by diving and cutting away 

 their fastenings from the rocks; those of inferior quality are usually torn 

 away with an instrument made for the purpose. The fresh sponges are ex- 

 posed to the sun and washed, for the purpose of removing the animal matter 

 with which they are filled. 



DESCRIPTION. A soft, elastic skeleton or framework of fibrous tissue sur- 

 rounding the original animal matter, which, being removed, leaves a number 

 of large and small cavities. The color is a light yellowish-brown. 



VARIETIES. The Turkey sponge is considered the best and belongs to the 

 species Euspongia mollisima; Euspongia zimocca, from the coast of Greece, is 

 harder and not so elastic. A still coarser sponge is Euspongia equina, collected 

 along the north coast of Africa. The various sponges of the West Indies 

 and Florida are different varieties of the three preceding species. 



CONSTITUENTS. A characteristic substance known as spongin, which 

 yields leucin and glycocoll when treated with sulphuric acid, and when treated 

 with KOH evolves ammonium hydrate. The ash is made up of various 

 compounds of iodine, sodium, magnesium, calcium, etc. 



USES. Its power to absorb liquids and to expand at the same time makes 

 sponge valuable as a surgical accessory in absorbing blood, dilating cavities, 

 cleansing surfaces, etc., but great care should be exercised in its use, so that 

 the same sponge may not be used more than once without being thoroughly 

 washed in a dilute solution of carbolic acid; otherwise there is danger of con- 

 tamination by infection, which is easily carried from one patient to another 

 when the same sponge is used repeatedly. Burnt sponge is occasionally 

 administered, on account of the iodides of sodium and potassium which it 

 contains, in cases of goiter and scrofulous swellings. 



610. CORALLIUM. CORAL. Oculi'na virgi'nea Lamarck. Class, Polypifera; 

 order, Hexacoralla. 



HABITAT. Atlantic Ocean and Mediterranean Sea. 



DESCRIPTION. A hard, calcareous substance produced by coral polypi. 

 The pieces are often branched, presenting a surface more or less porous and 

 striate, and the interior is radiate or hollow. 



VARIETIES. Besides Oculina virginea there are several other species, 

 among which may be mentioned Corallium rubrum, the red coral. 



CONSTITUENTS. Calcium carbonate 83 per cent., animal matter 7 to 8 

 per cent., magnesium carbonate 3 to 4 per cent., and ferric oxide 4.25 per cent, 

 (in the red coral). 



USES. Antacid. Used in tooth powders. Dose 15 to 15 gr. (0.3 to I Gm.). 



611. TESTA. OYSTER SHELL. 



SOURCE. O'strea virginia'na and 0. edulis, which excrete a calcareous 

 bivalved covering or shell, and inhabit the shallow coast water of the Atlantic 

 and Indian Oceans. 



DESCRIPTION. External surface rough, inner surface smooth and white, 

 the two toothless, hinged valves made up of imbricate, foliaceous layers, 

 presenting, when closed, an irregularly rounded, oblong, or ovate form. 



