The Saw-snouted Shark or Saw-fish (_Squalus pristis_), which grows to fifteen feet in length, and the Sword-fish (_Xiphias gladius_, _platypterus_), are furnished with peculiarly formidable weapons. The long flat snout of the former is set with teeth on both sides through its whole length, while the upper jaw of the latter terminates in a long sword-shaped snout. A twenty-feet long sword-fish once ran his sword with such violence into the keel of an East Indiaman, that it penetrated up to the root, and the fish itself was killed by the violence of the shock. The perforated beam, with the driven-in sword, are both preserved in the British Museum, and give a good idea of the prodigious power of the leviathans of ocean.
While most fishes only rely upon their well-armed jaws, their physical strength, or their rapidity, for attack or defence, some of them are provided with more mysterious weapons, and stun their victims or their enemies by electrical discharges.
[Illustration: Muscles and Electric Batteries of the Torpedo.]
The Torpedo of the Mediterranean is furnished with wonderful organs for this purpose, situated on each side of the anterior part of the body,--perfect galvanic batteries, consisting of a multitude of small prismatic columns, subdivided into cells, and interwoven with a multitude of nerves, which serve to disengage the electric fluid, and discharge it according to the will of the fish, or when it is excited by some external stimulus. The shock of the torpedo is not so strong as that of the electric eel (_Gymnotus electricus_) of the Orinoco, which is able to stun a horse, but its power suffices to paralyse the arm of a man. A Sly, or Silurus, found in the Nile or Senegal, and called by the Arabs _raasch_, or lightning, and one of the many Tetrodons inhabiting the tropical seas, is endowed with a similar faculty of producing galvanic shocks.
Some fishes, to whom nature has denied all other offensive weapons, have recourse to stratagem for procuring their food. Hidden in the mud, the Star-gazer (_Uranoscopus scaber_) exposes only the tip of the head, and waving the beards with which its lips are furnished in various directions, decoys the smaller fishes and marine insects, that mistake these organs for worms.