The mullet keeps fast

Explanation

proverb of the very gluttonous. For the mullet is so insatiable that on this account they used to call gapers and drinkers "mullets," as gluttons. Others say the proverb is of those who act justly but get nothing the more for their justice. For while the other fish eat one another, the mullet alone abstains from flesh-eating, and feeds, struggling, on the mud, as Aristotle says in his On Animals.