Melampygus

"[With the] black buttocks." A surname of Heracles. According to a comical tale, the Cercopes attempted to rob Heracles in his sleep, but were taken prisoner by him. To teach them a lesson, he tied them up by their heels to a pole which he carried over his shoulders. From their precarious position they saw Heracles' tanned and hairy buttocks, and recognized him for the Malampygos against whom their mother had warned them.

It became a proverbial cry among the Greeks when two men were seen quarreling — "Ne insidas in Melampygum!", "Look out for Melampygus!" (i.e. Heracles).

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