Detail from the procession of female saints on the left wall of the nave in Sant'Apollinare Nuovo, Ravenna
Like the other saints, Agnes brings her martyr's crown to present to thevVirgin and Child at the east (presbytery) end of the wall. Her name is given above the tree on the left: S[AN]C[T]A AGNES. This is one of the earliest examples of the saint's being accompanied by a lamb; the others in the procession do not have attributes.
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View of the entire left wall
More of St. Agnes
Photographed at the church by Richard Stracke, shared under Attribution-NonCommercial-ShareAlike license.