Hieroglyphics of Horapollo: Book II.: XCII. How the Presa...
Hieroglyphics of Horapollo, tr. Alexander Turner Cory, [1840]
When they would symbolise the presage of a plentiful vintage, they depict the HOU-POO; for if this bird sings [moans?) before the season of the vines, it is a sign of a good vintage.