| 1. Coral of the Astrea annanas. 2. Animal of the Caryophyllia solitaria. | 3. Animal of the Tubipora musica. 4. Animal and dwelling of the Cellepora hyalina. 5. Animal and central axis of the Gorgonia patula. |
SPONGE.
Sponge is a substance of a soft, light, porous, and elastic nature, which is found adhering to rocks at the bottom of the sea, in several parts of the Mediterranean, and particularly near the islands of the Grecian Archipelago; and which, in its natural state, is filled with animal jelly. The general uses of Sponge, arising from its ready absorption of fluids, and distension by moisture, are well known and of great importance. It is collected from rocks, in water five or six fathoms deep, chiefly by divers. When first taken from the sea, it has a strong and fishy smell, from the animal matter it contains, of which it is divested by being washed in clear water. No other preparation than this is requisite previously to its being packed up for exportation and sale. The growth of Sponge is so rapid, that it is frequently found in perfection on rocks, from which, only two years before, it had been entirely cleared.
As they are never designed to move from their places of abode, the surface of the Sponges is covered with innumerable small apertures or pores, communicating with a network of fine canals, which permeate every part of the substance and convey to the minute and simple creatures which form the living part of this curious compound animal, the food and water necessary for their support and respiration. These fine canals unite into larger passages, leading to orifices of considerable size usually placed on prominences of the surface; from these the water streams forth with such force, according to some observers, as to be perceptible by the eye.