Vibius Crispus on Domitian and Flies: An Unrecognised Bilingual Pun

It is argued that the story of how the emperor Domitian used to spend his time alone killing flies with a stylus has no historical basis but was invented by someone to explain the wit of a celebrated reply by the senator Vibius Crispus to the question of whether there was anyone in the palace with Domitian when he or she did not properly understand the wit of this reply. The reply that there was not even a fly in with Domitian, except perhaps in his wrestling-room, seems to have contained a pun between the Lain noun musca ‘fly’ and the Greek noun μύσχον ‘genital part’. However, this pun seems to have gone generally unrecognised as such because of the rarity of the Greek noun.