An astragal in the form of a torus holds the circular based basket, which enlarges to form a square. On one of its panels, four birds, with roughly outlined feathers, are facing each other in pairs. Around their heads are shown the feet of two birds, whose bodies are extended by long necks which curve to their feet. On each side, two other little birds, facing each other, form a lower register. In the upper register, coils of foliage meet in the centre of the panel and part again to support the corners in an imitation of a double capital. The abacus has disappeared as well as three of the four panels, which make it impossible to tell whether the capital is complete.

When it first came to the museum, this cornice was thought to have come from Saint Genevieve's Abbey. But today this notion is rejected because the differences are evident, for example, the module of the capital, whose dimensions correspond neither to the capitals of the nave nor to those of the choir of Saint Genevieve, and the single strands of foliage contrasting with those at Saint Genevieve which are characterized by two threads separated by a rope. Finally, the shapes of the birds and the work on the feathers can be traced back to a sculptural technique from Paris that was only seen after 1130. Altough it is impossible, on the basis of our current knowledge, to work out the origin of this fragment of capital, it seems plausible to place it in the lineage of the birth of gothic sculpture in Paris during the second third of the 12th century.