Scholars often assume that Old Comedies based on mythological stories differed from other Old Comedies primarily by their mythological plot material, and that therefore they shared the structural features of the surviving plays of Aristophanes. I show that the evidence may instead indicate that these Old Comedies did not as a rule have a parabasis or an agon. The structure of mythological Old Comedy could then have resembled the satyr play more closely than Aristophanic Old Comedy, meaning genre did not (...) necessarily determine form. (shrink)