CARTILAGINOUS PISHES. 
505 
commotions. This apparatus is placed in the interval between the 
end of the muzzle and the extremity of the fin, and completes the 
rounded disk of the body. The mouth is small, the slit crosswise ; the 
jaws bare ; the teeth in squares of five. The eyes are small ; behind 
them are two star-like spout-holes. On the lower surface of the breast 
are two rows of small transverse slits, openings of the gill pouches, 
like those ot the rays. The tail is thick, short, and conical, carrying 
part of the ventral, and terminating in a sort of caudal fin. On the 
back are two small, soft, and adipose fins. The skin is smooth ; its 
colour varies with the species; generally it is reddish-brown, with 
eye-like spots of a deep blue in the centre ; sometimes azure, and sur- 
rounded by a great brownish circle ; the spots being five or six. These 
curious fishes are found in the Channel and on the shores of the 
Mediterranean. 
The electrical effects produced on the fisherman who seizes them 
were noted from early times ; but Eedi, the Italian naturalist of the 
seventeenth century, was the first who studied them scientifically. 
Having caught and landed one of them with every precaution, “ I 
tad scarcely touched and pressed it with my hand,” says the Italian 
naturalist, “ than I experienced a tingling sensation, which extended 
to my arms and shoulders, which was followed by a disagreeable 
trembling, with a painful and acute sensation in the elbow joint, 
■which made me withdraw my arm immediately.” 
Reaumur also made some observations upon the Torpedo. “ The 
benumbing influence,” he says, “ is very different from any similar 
sensation. All over the arm there is a commotion which it is impos- 
sible to describe, but which, so far as comparison can be made, re- 
sembles the sensation produced by striking the tender part of’ the 
elbow against a hard substance.” Redi remarks, besides, that the pain 
and trembling sensation resulting from the touch diminishes as the 
death of the Torpedo approaches, and that it ceases altogether when 
tile animal dies. 
In the seventeenth century, the fishermen affirmed that the sensa- 
tion was even communicated through the line by which it was caught, 
>ind even by the water. Redi does not deny this phenomenon, neither 
does he confirm it. He states that the action of the animal is never 
rru,re energetic than when it is strongly pressed by the hand, and 
’flakes violent efforts to escape. Neither Redi nor Reaumur, however. 
