The octagonal transept has pilasters with derivative, sort-of minimalist Corinthian pilasters folded into its corners. This supports an entablature with a dentillated architrave, a frieze of oak leaves and a cornice with modillions. The Chigi star is in the corners of the frieze. The diagonal sides flanking the nave arch have a pair of cantorie or balconies with balustrades. These contain two gilded Baroque organ cases. The organ dates from 1655.