MALACOPTIJKYGII APODES. 553 



placed against the base of the anal fin. These four organs 

 are sorts of bundles, and their bulk is so considerable that it 

 forms perhaps one-third of the entire fish. The two large 

 ones are so wide as to be separated one from the other 

 towards the top only by the dorsal muscles, towards the 

 middle of the body, by the natatory or swimming bladder, 

 and towards the bottom by a partition, with which they inti- 

 mately unite, while they are attached by a loose but very 

 strong cellular membrane to the other parts which they touch. 

 The small lower bundles are separated from the two large 

 upper ones by a longitudinal and almost horizontal mem- 

 brane. Each of these four bundles is composed of a great 

 number of tendinous expansions, long, parallel, horizontal, 

 and separated from each other by about the twentieth part of 

 an inch. Hunter reckoned thirty-four in one of the large- 

 bundles, and fourteen only in a small one. Other vertical 

 plates or expansions of the same nature, but much more 

 numerous, cut the preceding almost at right angles ; this forms 

 a wide and deep net-work composed of a multiplicity of small 

 cells. Hunter reckoned two hundred and forty of these ver- 

 tical plates in a length of about eleven lines. The interior 

 of the cells is filled with an unctuous, and as it were gelatinous 

 kind of substance. 



This apparatus, which, like that of the torpedo, is altogether 

 analogous to the Voltaic pile, is put in play by a system of 

 nerves emanating from the vertebral or spinal marrow, com- 

 posed of as many trunks as there are vertebrae, and it receives, 

 besides, some branches of a large nerve, running in a straight 

 line from the cranium to the extremity of the tail, above the 

 back-bone. All the ramifications of these various nerves arc 

 spread out in the cells of the electric organs, and thus become 

 so many instruments capable of striking with death or torpor 

 all the animals within reach of their influence. 



M. de Lacepede has compared the composition of these 



