The choir walls, containing an elegant sedilia and piscina, remain standing to the height of 9 feet, and it is questioned whether the choir was ever finished during the restoration. There is a string-course all round; the building is of fifteenth century work, and occupies the place of an earlier choir, which has been demolished. The wall at the east end of the nave, which separates it from the transept, may have been erected during the restoration of the fifteenth century, with the intention of rendering the nave a complete church until the transept and choir were restored. This seems to have been in progress when the Reformation interrupted the work. The design of the sedilia resembles that at St. Monans, Fife, and adjoining the sedilia is the piscina, the aperture of which is still visible. The north transept is in ruins, but the north wall, with the remains of a fine traceried window, still exists, as well as a traceried window in the west wall. The south transept is also in ruins, while the tower and spire have disappeared. St. Mirin's Chapel is well preserved, but the openings connecting it with the south transept are built up. The nave survives as a whole, and contains six bays, divided by massive piers, and surmounted by a triforium and clerestory. There is a north porch, and two doorways from the cloister on the south side. The oldest portion of the building is pronounced to be the eastern part of the south wall of the south aisle of the nave, where it adjoins the transept. This portion of the wall consists of three bays, containing the S.E. doorway from the cloister to the nave, and three pointed windows in the upper part. The doorway is of the transition style, and the windows above are simple in style, and are early pointed work--this part of the building probably dating from the first half of the thirteenth century.[387] The western portion of the south aisle of the nave and the whole of the south clerestory are evidently portions of the restored church of the fifteenth century.[388] The south aisle wall contains the S.W. and S.E. doors from the nave to the cloister.