But there is another feature of the side aisle vaults which is worthy of note before turning to the more developed churches which resemble Bury in their arrangement of vaulting bays. This is the use of small caryatid figures which appear at the springing of the diagonal ribs (Fig. 23).[171] These would seem to serve a purely decorative purpose, perhaps to distract attention from the great size of the ribs behind them, or to give an apparent lightness to the vault itself by seemingly placing its burden upon such insignificant shoulders, or more probably still, the figures served to break the transition from shaft to rib by concealing the impost of the latter. Whatever their explanation, other examples besides those at Bury are to be seen. Of these, the angels--now badly mutilated--at the base of the ribs in the narthex of Saint Ours at Loches (Indre-et-Loire) (Fig. 24)[172] are especially interesting, and perhaps account for the tiny figures employed at the springing of the ridge ribs in a number of churches in Anjou, such as Angers, Saint Serge (Fig. 21), as well as for the larger figures in the apse of Notre Dame-de-la-Couture at Le Mans (Fig. 20).[173] It may even be through the influence of such figures as these that grotesques were used to support the small shafts in the arcade of the triforium passage in the cathedral of Nevers (Nièvre) (Fig. 25). [Illustration: FIG. 24.--LOCHES, SAINT OURS.] SQUARE NAVE AND RECTANGULAR AISLE BAYS CONTINUED [Illustration: FIG. 25.--NEVERS, CATHEDRAL.] Returning to the churches later in date than Bury but vaulted on the same plan, it will be found that there are but few examples in France, an interesting fact for which an explanation will later be attempted.[174] The lower story of the Sainte Chapelle at Paris (cir. 1250) furnishes one of the rare examples, but here the nave and aisles are of the same height and so do not exactly resemble the system at Bury. Because of their narrowness, the side aisle vaults of the Sainte Chapelle did not furnish proper abutment for those of the nave, and the builders found it necessary to add tie-rods and even transverse half arches forming veritable interior flying buttresses at about half the height of the transverse ribs. This is, however, a most unusual arrangement.