CHAPTER XI 



ELECTEICAL FISHES 



I. STRUCTURE AND CONSTITUTION OF ELECTRICAL ORGANS 



THE wonderful physiological properties of certain fishes, e.g. more 

 particularly the Torpedinidce of the Mediterranean, and the 

 Siluroids (Mcdapterurus electricus) of the Mle and other African 

 rivers, have been known and dreaded from the earliest times. 

 The most superficial acquaintance with any representative of 

 this small and highly specialised group of fishes at once reveals 

 their power, when touched, of exhibiting activities, which were 

 first shown to be similar to electrical discharges by Adanson 

 (1751). Francesco Eedi (1666) had long since pointed out, in 

 his masterly anatomical investigation of the electric ray (Tor- 

 pedo), that the mysterious power of the electrical fishes was, in 

 all likelihood, associated with special organs, situated symmetric- 

 ally on both sides of the head. These he described from their 

 shape as " sickle-shaped bodies, or perhaps muscles." " It appeared 

 to me," writes Redi, in describing his experiments, " as if the 

 painful action of the electric ray was located in these two sickle- 

 shaped bodies, or muscles, more than in any other part." From this 

 may be dated the first scientific treatment of the problem. For 

 centuries it had sufficed to describe the striking and unpleasant 

 sensations resulting from unwary contact with electrical fishes. 

 The Latin name torpedo, the French torpille, the Italian 

 tremola, the old Greek narke for the ray, the Arabic radd or 

 radsch for the cat-fish, and the Spanish templador for the South 

 American eel, all point to the stunning and shattering effect 

 of the shock from an electric fish, without hazarding anything 

 as to the cause of the manifestation. 



