To Prove That Earth-Worms Have a Nervous System
Place an earth-worm upon a plate of zinc, resting on a larger plate of silver.—The animal, as soon as it approaches the silver, seems to be repulsed by a painful sensation, and at last becomes fatigued by its repeated and fruitless exertions to make its escape, which nothing apparently prevents.
This evidently proves that the animal is provided with a nervous system, as experiments have proved that Galvanic irritation is excited only in the nerves.