THE ELECTRIC FISH

The idea of a fish being able to generate electricity strong enough to light lamp bulbs or even to run a small electric motor is almost unbelievable, but several kinds of fish are able to do this. Even more strangely, this curious power has been acquired in different ways by fish belonging to very different families. The best known are the electric rays, or torpedoes, of which several kinds live in warm seas. They possess on each side of the head, behind the eyes, an organ consisting of small hexagonal shaped cells rather like a honey comb. The cells are filled with a jelly like substance, and contains a series of flat electric plates.
The fish gives an even more powerful shock. The system is different from that of the torpedo in that the electric plates run longitudinally and are supplied with nerves from the spinal cord. Consequently, the current passes along the fish from head to tail. The electric organs of these fish are really altered muscles and like all muscles, are to tire, so they are not able to produce electricity for very long.
The electric catfish has a different system again by which current passes over the whole body from the tail to the head. The shock given by this arrangement is not so strong as the other two, but less unpleasant. The electric catfish is a slow, lazy fish, fond of gloomy places and grows about one metre long, it is eaten by the Arabs in some as areas.
The power of producing electricity may serve these fish both for defense and attack. If a large enemy attacks, the shock will drive it away, but it appears that the catfish and the electric use their current most often against smaller fish, stunning them so that they can easily be overpowered.

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