Derived from ancient sources, like the marble itself, the carved vine, grapes and birds are symbolic of the sacrament of communion. The pilasters were originally part of a choir screen surrounding an altar.
[ Raoul Heilbronner, Paris (sold 1909)]
Breck, Joseph. "Principal Accessions." The Metropolitan Museum of Art Bulletin, o.s., 4, no. 11 (November 1909). pp. 208, 214.
Castelnuovo-Tedesco, Lisbeth. "Romanesque Sculpture in North American Collections. XXIII. The Metropolitan Museum of Art. Part III: Italy (2)." Gesta 24, no. 4 (1985). no. 3, pp. 159-60, fig. 5.
Castelnuovo-Tedesco, Lisbeth, and Jack Soultanian. Italian Medieval Sculpture in The Metropolitan Museum of Art and The Cloisters. New York: The Metropolitan Museum of Art, 2010. no. 5, pp. 18–21.