206 THE TORPEDO. 



the upper parts is dark chocolate-brown mottled with a darker hue, and very rough. Along 

 the back runs a row of short, sharp spines, their points directed backwards, and the under 

 parts are smooth and of a dull brownish-white The length of an adult specimen is seven or 

 eight feet. 



THE RAYS. 

 THIS group of fishes forms a separate order, in which are seven families. 



THE SAV-FISH (Pristis antiquorum) is a familiar form, sometimes reaching the length of 

 fifteen feet ; Laving a saw-like snout four or five feet in length. It is found in nearly all the 

 warmer seas, and even in the colder regions. It is reported that this Ray swings itself side- 

 wise with rapidity and thereby cuts down fishes by the double-edged saw, which proves a 

 most effective weapon. 



The color of the Saw-fish is dark gray above, nearly black in some individuals, the sides 

 are ashen, and the abdomen white. It often attains a great size, measuring fifteen or eighteen 

 feet in length, including the saw. 



THE TENTACULATED SAW-FISH (PristiopTiorus drrdtus) is worthy of notice as forming a 

 transition link between the sharks and the true Saw-fish. In this creature, the snout is 

 lengthened and armed with spines ; but these structures are of different lengths, hooked, 

 and only attached to the skin, and not implanted in the bone, as is the case with the true 

 Saw-fish. 



IN the true Rays, or Raidse, the fore part of the body is flattened and formed into a disc- 

 like shape, by the conjunction of the breast fins with the snout. 



Our first example of the Rays is the TORPEDO, a fish long celebrated for its power of emit- 

 ting at will electrical shocks of considerable intensity. In consequence of this property, it is 

 sometimes called the CUAMP-FISH, CRAMP RAY, ELECTRIC RAY, or NUMB-FISH. 



The object of this strange power seems to be twofold, namely, to defend itself from the 

 attacks of foes, and to benumb the swift and active fish on which it feeds, and which its slow 

 movements would not permit it to catch in fair chase. It does not always deliver the electric 

 shock when touched, though it is generally rather prodigal of exercising its potent though 

 invisible arms, but will allow itself to be touched, and even handled, without inflicting a 

 shock. But if the creature be continually annoyed, the shock is sure to come at last, and in 

 such cases with double violence. It has been observed, moreover, that the fish depresses its 

 eyes just before giving its shock. 



The power of the shock varies greatly in different individuals, with some being so strong 

 as to cause the recipient to fall to the ground as if shot, and, with others, so feeble that it is 

 hardly perceived. According to M. de Quatrefages, the fishermen are sometimes unpleasantly 

 made aware that they have captured a Torpedo in their meshes, by the sudden shock through 

 their arms and breast as they are hauling in their net. Anglers, too, are sometimes struck by 

 means of the line which they are holding ; and I presume that in either case the line must be 

 wet, or it would not act as a conductor of the electrical fluid. 



One of these fishes was placed in a vessel of water, and a duck was forced to swim about 

 in the same vessel. The Torpedo soon became excited, and in a few hours the duck was dead. 

 Fish, also, of different kinds are killed by this remarkable influence ; and it is plausibly sug- 

 gested by one writer, that this mode of destruction would render them liable to rapid decom- 

 position, and would aid the organs of digestion in a creature like the Torpedo, where they are 

 but imperfectly developed. 



The shocks of this fish were once used as remedies for gout and fevers. In the first 

 case, the patient had to lay his foot on the Torpedo, and bravely hold it in its place, despite 

 of all the shocks sent by the angry fish through the sensitive limb of the aggressor ; and 

 in the latter case the Torpedo was used, as it were, to frighten the fever out of the system. 



