<P> The Romanesque period produced a profusion of sculptural ornamentation . This most frequently took a purely geometric form and was particularly applied to mouldings, both straight courses and the curved moldings of arches . In La Madeleine, Vezelay, for example, the polychrome ribs of the vault are all edged with narrow filets of pierced stone . Similar decoration occurs around the arches of the nave and along the horizontal course separating arcade and clerestory . Combined with the pierced carving of the capitals, this gives a delicacy and refinement to the interior . </P> <P> In England, such decoration could be discrete, as at Hereford and Peterborough cathedrals, or have a sense of massive energy as at Durham where the diagonal ribs of the vaults are all outlined with chevrons, the mouldings of the nave arcade are carved with several layers of the same and the huge columns are deeply incised with a variety of geometric patterns creating an impression of directional movement . These features combine to create one of the richest and most dynamic interiors of the Romanesque period . </P> <P> Although much sculptural ornament was sometimes applied to the interiors of churches, the focus of such decoration was generally the west front, and in particular, the portals . Chevrons and other geometric ornaments, referred to by 19th - century writers as "barbaric ornament", are most frequently found on the mouldings of the central door . Stylized foliage often appears, sometimes deeply carved and curling outward after the manner of the acanthus leaves on Corinthian capitals, but also carved in shallow relief and spiral patterns, imitating the intricacies of manuscript illuminations . In general, the style of ornament was more classical in Italy, such as that seen around the door of San Giusto in Lucca, and more "barbaric" in England, Germany and Scandinavia, such as that seen at Lincoln and Speyer Cathedrals . France produced a great range of ornament, with particularly fine interwoven and spiralling vines in the "manuscript" style occurring at Saint - Sernin, Toulouse . </P> <Ul> <Li> <P> Detail of an apse of Abbey d'Arthous, Landes, France showing corbels representing aspects of sin such as lust, drunkenness and ignorance . </P> </Li> <Li> <P> The portal of the Hermitage of St Segundo, Avila, has paired creatures . and decorative bands of floral and interlacing . The pairing of creatures could draw on Byzantine and Celtic models . </P> </Li> <Li> <P> The carving of the polychrome porch of the Saint - Michel - D'aiguilhe chapel, the Aiguilhe, Haute - Loire, France, (11th century), has paired mermaids, and the Lamb of God </P> </Li> <Li> <P> On these mouldings around the portal of Lincoln Cathedral are formal chevron ornament, tongue - poking monsters, vines and figures, and symmetrical motifs . </P> </Li> <Li> <P> St Martin's Church, Gensac - la - Pallue has capitals with elaborate interlacing . </P> </Li> </Ul>

Romanesque churches' portals were of special importance because they
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