The earliest figure of this character to which I can refer is the mosaic in the oratory of San Venanzio, in the Lateran, the work of Greek artists under the popes John IV. and Theodorus, both Greeks by birth, and who presided over the Church from 640 to 649. In the vault of the tribune, over the altar, we have first, at the summit, a figure of Christ half-length, with his hand extended in benediction; on each side, a worshipping angel; below, in the centre, the figure of the Virgin according to the ancient type, standing with extended arms, in a violet or rather dark-blue tunic and white veil, with a small cross pendant on her bosom. On her right hand stands St. Paul, on her left St. Peter; beyond St. Peter and St. Paul, St. John the Baptist holding a cross, and St. John the Evangelist holding a book; and beyond these again, St. Domino and St. Venantius, two martyred saints, who perished in Dalmatia, and whose relics were brought out of that country by the founder of the chapel, John IV., himself a Dalmatian by birth. At the extremities of this group, or rather line of figures, stand the two popes, John IV. and Theodorus, under whom the chapel was founded and dedicated. Although this ancient mosaic has been many times restored, the original composition remains. Similar, but of later date, is the effigy of the Virgin over the altar of the archiepiscopal chapel at Ravenna. This mosaic, with others of Greek work, was brought from the old tribune of the cathedral, when it was altered and repaired, and the ancient decorations removed or destroyed. Another instance, also, at Ravenna, is the basso-relievo in Greek marble, and evidently of Greek workmanship, which is said to have existed from the earliest ages, in the church of S. Maria-in-Porto-Fuori, and is now preserved in the S. Maria-in-Porto, where I saw it in 1847. It is probably as old as the sixth or seventh century. In St. Mark's at Venice, in the grand old basilica at Torcello, in San Donate at Murano, at Monreale, near Palermo, and in most of the old churches in the East of Europe, we find similar figures, either Byzantine in origin, or in imitation of the Byzantine style.