Wikipedia entry.) Doesn't that seem a rather odd myth, and hard to fathom how it started?* Now that I think of it, what does the (much less specific) "kiss my ass" derive from?
* But then again, how did any weird story about what witches could do get started. I read about this one years ago:
German clergyman Heinrich Kramer described the epidemic in Malleus Maleficarum (1486)—one of the most famous medieval treatises on witches—writing: “Witches ... collect male organs in great numbers, as many as 20 or 30 members together, and put them in a bird’s nest, or shut them in a box.” But the disembodied penises didn’t just hang around. “They move themselves like living members and eat oats and corn, as has been seen by many,” Kramer wrote.It's the little detail of "eating oats and corn" that really floors me as a bizarre thing to dream up.