The Earwig.
This insect is supposed to have a "fondness" for getting into the human ear, the effect of which, it has been believed, is to penetrate the brain and cause madness. The earwig is not more likely than any other insect to enter the ear. The wings of the earwig, when fully expanded, are in shape precisely like the human ear, from which fact it is highly probable that the original name of the insect was ear-wing and not ear-wig, which appears to be entirely without meaning. The name is also traced to the Saxon ear-wigca, from its destroying ears of grain and fruit.