When pursuing their prey they use their great fins which resemble wings, and with these and their tail, they beat the waters in order to fall unexpectedly upon their prey, as the Eagle swoops upon its victim.
The Torpedo has no spines which can wound, but it has a much more powerful weapon of defence. Like the Electrical Eel, this Fish has the power of producing violent electrical shocks.
The electrical effects produced on the fisherman who seizes one of these Fish, were noted from early times; but Redi, 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 had scarcely touched and pressed it with my hand,” says this Naturalist, “than I experienced a tingling sensation, which extended to my arms and shoulders, and which was followed by a disagreeable trembling, with a painful and acute sensation in the elbow joint, which made me withdraw my arm immediately.”
Other Naturalists have described similar sensations, and careful study has been made of this Fish to discover the cause of this shock, and the hidden power possessed by the Fish of storing up this animal electricity. It still remains a mystery, however, in spite of extensive experimenting.
The body of the Torpedo or Cramp-fish is almost circular, and it is thicker than others of the Ray family. The skin is soft and smooth, and of a yellowish color marked with darker spots. The eyes are very small, and behind them are two star-like spout-holes; the mouth is small, and the long tail tapers to a point, finished with a sort of caudal fin. These curious Fishes are found in the English Channel and along the shores of the Mediterranean.
[Illustration: Diver Battling with a Shark.]
The Sharks, like the Raias, have their mouth furnished with jaws, and for this reason they are classified in the same group of Cartilaginous Fishes, as distinct from the Lampreys and the Sturgeons. This family includes not only the Sharks, but the Dog-fishes, Hammerheads and the Saw-fish. All the species have a lengthened body, merging into a thick tail and a rough skin.
The Shark becomes the terror of the sea almost as soon as it is born. At first it eats the Cuttle-fish, Molluscs, etc., then the Flounders and Cod-fish. But the prey which has the greatest charm for him is Man. He will even attack a diver in the strong diver’s costume, and in the waters where these “Hyenas of the Seas,” (as the Sharks are sometimes called) are to be found, the divers find it necessary to make special preparations for fighting them.