﻿Sponges. 



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escape by special openings. Thus the channels perform the two functions 

 of digestion and respiration. The rapid currents of serated water which 

 traverse them lead into them the substances necessary to the nourishment 

 of these strange creatures, and at the same time carry off all excremental 

 matter. At the same time the walls of these canals present a large ab- 

 sorbing surface, which separates the oxygen with which the water is 

 charged and disengages the carbonic acid which results from respiration. 



At the present time sponge fishing takes place principally in the Gre- 

 cian Archipelago and the Syrian Littoral. The Greeks and Syrians sell 

 the product of their fishing to the Western nations. Fishing usually com- 

 mences towards the beginning of June on the coast of Syria and finishes 

 at the end of October. But the months of July and August are pecul- 

 iarly favorable to the sponge harvest. Lalakia furnishes about ten boats 

 to the fishery. Batroun twenty, Tripoli twenty-five to thirty. Kalki fifty. 

 Simi about one hundred and eighty and Kalminos more than two hundred. 

 The boat's crew consists of four or five men, who scatter along the coast 

 for two or three miles in search of sponges under the cliffs and ledges of 

 rock. 



Sponges of inferior quality are gathered in shallow waters ; the finer 

 kinds are found only at a depth of from twenty to thirty fathoms. The 

 first are fished for with a three-toothed harpoon, by the aid of which they 

 are torn from their native rocks, but not without deteriorating them more 

 or less. The finer kinds of sponges are collected by divers : aided by a 

 knife, they are carefully detached. Thus the price of a sponge brought 

 up by diving is much more than that of one harpooned. Among divers, 

 those of Kalminos and of Psara are particularly renowned. They will 

 descend to the depth of twenty-five fathoms, remain down a shorter time 

 than the Syrian divers and yet bring up more sponges. The fishing of the 

 Archipelago furnishes few fine sponges to commerce, but a great quantity 

 of very common ones; the Syrian fisheries furnish many of the finer kinds, 

 while those from the Barbary Coast are of great dimensions and of a very 

 fine tissue. 



As fossils, the sponges are among our oldest inhabitants, occurring, as 

 they do. largely in the silurian and then on through nearly all the forma- 

 tions, until in the cretacious we find the chalk almost wholly composed <>f 

 the remains of sponges and rhizopods. Shells perforated by the Boring 

 Sponge (Cliona) appear in the silurian rocks, while species of the same 

 genus inhabiting our seas to-day show that their race has survived from 

 the earliest Palacozic times until now. The great bulk of the Jurasic, 



Sponge-Limestone," consists of the remains of calcareous sponges. This 



