Near the beginning of Infenzo 31, Dante's pilgrim mistakes the giants of Cocytus for a wall of towers surrounding a city. While Dante's account does not have a clear parallel in the Aeneid or Metamorphoses, it summons the Thebaid. In the underworld of Statius' poem, soldiers who are the offspring of Mars encircle a blood-red lake. Statius calls them earth-born, and his phrase links them with the rebellious giants of classical myth. Statius also stresses their love of war. So too, Dante emphasizes the ferocity of his giants and associates them with Mars; and Cocytus is fed by Phlegethon, which is red with blood. Dante finds in Statius a precedent for commenting on the moral qualities of his giants, and he evokes the Thebaid to underscore their violence and stupidity. In doing so he reinforces the authority of Statius, who will guide the pilgrim through purgatory; underscores Thebes as a model for the city of Dis; and points to the Thebaid as a poem that is possibly more significant than Virgil's Aeneid.