THE ELECTRIC TORPEDO. 179 



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below, by the common skin of the animal, under which 

 there is a thin fascia spread over the whole organ. This 

 fascia is composed of fibres, which run longitudinally^ 

 or parallel with the back : these fibres appear to be per- 

 forated in innumerable places, which gives the fascia an 

 appearance of being fasciculated : its edges, all round, 

 are closely connected to the skin, and at last appear to 

 be lost, or to degenerate into the common cellular mem- 

 brane of the skin. Immediately under this is another 

 membrane, exactly of the same kind, the fibres of which, 

 in some measure, decussate those of the former, and pass 

 from the middle line of the body outwards and backwards : 

 the inner edge of this is lost with the first membrane ; 

 the anterior, outer, and posterior edges are partly attached 

 to the semicircular cartilages, and partly lost in the 

 common cellular membrane. This inner fascia is con- 

 tinued into the electric organ by many processes, and 

 thereby makes the membranous sides or sheaths of the 

 columns, which are presently to be described. 



(159.) Each organ is about five inches in length, and 

 at the posterior end three in breadth, though it is but 

 little more than half as broad at the posterior extremity; 

 each consists wholly of perpendicular columns, reaching 

 from the upper to the under surface of the body, and 

 varying in their lengths according to the thickness of 

 the body. The shape of these columns, also, is very 

 variable ; the greater number are either irregular hex- 

 agons, or irregular pentagons: their coats are very thin, 

 and closely connected with each other, having a kind of 

 loose network of tendinous fibres between the columns, 

 which they unite more firmly; and this purpose is fur- 

 ther effected by strong unelastic fibres : the number of 

 these columns, in different torpedos of moderate size, 

 appears to be about 470 in each organ, but in a very 

 large individual they were 1182; they must, therefore, 

 increase, both in size and number, with the growth of 

 the animal. Each column is divided by horizontal par- 

 titions, which appear to contain a fluid : they are not 

 totally detached from each other, for they sometimes 



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