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a commercial value indigenous to the Bahama Islands in 

 particular, that this little pamphlet is devoted. The 

 sponges of the world number many thousand species, 

 which are distributed with equal abundance throughout the 

 arctic, temperate, and tropical seas. Some inhabit the 

 shallow water close in shore, and are left exposed to the 

 influence of the atmosphere with every fall of the tide ; 

 others are exclusively confined to the abyssal depths of the 

 ocean, while a small but interesting minority are denizens 

 of our inland lakes and rivers. Out of the sum-total of 

 known sponges, less than a dozen species, with their many 

 local varieties, all inhabitants of the sub-tropical seas, fall 

 under the category of economic species, and are made the 

 subject of an important fishery. As a matter of fact, the 

 economic value of the sponges of commerce depends 

 entirely upon the nature and arrangement of the materials 

 that compose their skeleton, it being only such lifeless 

 inorganic elements that are present in the article known as 

 sponge when brought to the market. A sponge in its 

 living state — freshly torn from its habitat at the bottom of 

 the sea — bears but little, if any, resemblance to our familiar 

 " companion of the bath " or adjunct of the toilet table. 

 The entire substance of the fine fibrous amber-coloured 

 tissue of which it is, in its commercial form, composed, is, 

 in such living condition, completely hidden within a glairy 

 gelatinous matrix, having somewhat the consistence and 

 aspect of a weak glue, with somewhat denser external 

 pellicle. This glue-like substance represents the organic 

 or animal element of the sponge body, its relationship to 

 the enclosed sponge fibre being essentially identical with 

 that which subsists between our own living tissues and the 

 inanimate bony skeletons that is contained within them. 

 By the process of maceration and washing, the gelatinous 



