Evicted

http://www.google.com/patents/about?id=0FVOAAAAEBAJ

A trap for gullible tapeworms, patented in 1854 by Alpheus Myers.

The capsule is baited and swallowed by the patient, after a fast “to make the worm hungry.” The worm seizes the bait, the trap closes on its head, and the doctor withdraws the whole length of the parasite from the patient’s stomach, presumably with a magician’s flourish.

“In constructing the trap, care should be taken that the spring g, is only strong enough to hold the worm, and not strong enough to cause his head to be cut off.”