ELECTRICITY OP TORPEDO AND MALAPTERURUS. 21 



the pectoral fins ; leaving between these organs, and the head 

 and gills, an oval space, in which is placed the electrical 

 apparatus of these fish. This apparatus is composed of a 

 multitude of membranous vertical tubes, pressed one against 

 the other, like the cells of bees, and subdivided by horizontal par- 

 titions into small cells filled with mucous matter ; it is supplied by 

 several very large branches of the pneumo-gastric nerves. It is in 

 these singular organs that the electricity is produced, by which the 

 Torpedo can give violent shocks to those who touch them, and 

 produce the same phenomena which in physical experiments 

 result from an ordinary electric current ; such as sparks, che- 

 mical decompositions, &c. These fish are less powerful than the 

 Gymnotus ; but can nevertheless strike with sufficient force to 

 benumb the arms of those who touch them ; and it is pro- 

 bably by this means, that they seize their prey. It has been 

 ascertained that this property is dependent on the posterior lobe 

 of the Encephalon; and that by destroying this lobe, or by cutting 

 the nerves which spring from it, the power of producing these 

 shocks is destroyed. Several species exist in the seas which 

 wash the shores of Europe. 



543. The electrical Silums or Malapterurus inhabits the Nile 



FIG. 265. ELECTRIC MALAPTJSRURUS. 



and the Senegal ; its length is from about ten to fourteen inches ; 

 and it appears to derive the power of giving electrical shocks 

 from a particular tissue situated between the skin of the sides 

 and the muscles, and having the appearance of a laminated 

 cellular tissue. The Arabs give to this fish the name of Raasch, 

 which signifies thunder. 



544. Fishes multiply by means of eggs ; and the number of 

 these is sometimes immense, several hundred-thousands being 

 often produced at a time. In general they have only a mucila- 



