Fig. 58.—Worms, Cathedral.
any wall rib. These “Gothic domes” were frequently polygonal as well as circular. Thus in the cathedral of Worms [(Fig. 58)] there is an octagonal lantern, on squinches, surmounted by a vault with eight cells of decidedly domical type, the whole being only slightly different from a lobed dome. A more developed double chevet, dating from the second half of the fifteenth century, appears over the crossing of the cathedral of Evreux (Eure),[324] where there is also a complete system of ribs.[325] The form of the pendentives is that of flat triangles, and they are decorated with elaborate designs in flamboyant tracery. Similar flat triangles but with a series of mouldings at the top, are used to support the octagonal lantern of Coutances cathedral [(Fig. 59)], perhaps the most beautiful in France, and apparently dating from the second half of the thirteenth century. Its vault is in sixteen cells, two to each lantern wall, and each containing a lofty window, the whole clerestory rising above a lower stage of coupled arches with a narrow passage behind them.