The choir consists of two double compartments, and in its plan as a whole agrees with that of the nave. There are, however, some differences in the details. The piers of the great arcades, although similar in motive to those of the nave, are much longer from east to west, and are, in fact, more like sections of wall than piers. The clerestory is quite unlike that of the nave, having a plain round-headed arch in each bay, with a corresponding window, and is destitute of a wall passage. The triforiums on both sides of the choir and on the east side of the transepts are all very similar. They are lighted by windows, consisting of two small round-headed openings, about twenty inches apart, under a containing arch. The buttressing arches, which are opposite the piers, are semicircular in form, and are contemporaneous with the arcades. Each transept has two double bays, with an aisle on the east side. The vault on the north transept has one transverse arch, which is semicircular, the double bay to the north having a single quadripartite vault with segmental diagonal ribs. All the ribs are moulded with a roll between two hollows. The south transept has a similarly formed vault, but the ribs are enriched with zigzag. The triforium and other upper parts of the church are reached by staircases contained in two square internal projections which are in the north-west and south-west angles of the transept. The end walls of the transepts were probably lighted by three tiers of windows; the lowest--which still remains--though blocked up, in the south transept, is a single round-headed window. It is difficult to say what was the arrangement above, but probably there were three windows on the triforium level and one on that of the clerestory. Passages crossed the ends at these levels, but none now remain in their original state. The vaults of the aisles of the choir, transepts, and nave, are quadripartite and are the same throughout, except that the diagonal ribs of the nave aisles beyond the two eastern bays have zigzag upon them.