Unidentified Apostle (St. Matthias?)

Detail from a retable fragment in the Metropolitan Museum

With his right hand the saint holds a scroll, which is sometimes the attribute of St. Matthias.  None of the other apostles in the fragment has a scroll. The object in his left hand could conceivable be a book, which is also at times an attribute of St. Matthias.

More of St. Matthias

Photographed at the site by Richard Stracke