Outside of the chapel is the tomb of Guilaumme Durand, Bishop of Mende, celebrated canon lawyer and liturgist, died in 1296. His Cosmatesque monument, signed by Giovanni di Cosma was moved out to here during a re-fitting in 1670. Above the effigy is a mosaic of the Madonna and Child with SS Dominic and Privatus, with a smaller figure of Bishop Durand kneeling in prayer.