panions, and
consequently the arch over them, the triumphal arch of the sanctuary, is
wider and loftier than the other arches. The bays to the north-east and
the south-east are also wider than the bays at the opposite angles. The
apse is semicircular within, and shows three sides on the exterior. As
in S. Sophia and S. Irene, there is no prothesis or diaconicon.

The pairs of columns, both below and above, are alternately verd
antique and red Synnada marble, resting on bases of the blue-veined
white marble from the island of Marmora. The capitals on the lower order
are of the beautiful type known as the 'melon capital,' a form found
also in San Vitale at Ravenna and in the porch of S. Theodore in
Constantinople (p. 246). The neckings are worked with the capitals, and
enriched by 'egg-and-dart' pointing upwards. In the centre of the
capitals was carved the monogram of Justinian or that of Theodora. Most
of the monograms have been effaced, but the name of the empress still
appears on the capital of the western column in the south bay, while
that of Justinian is found on the first capital in the south-western
bay; on both capitals in the north-western bay, accompanied by the title
Basileus; and, partially, on the last capital in the north-eastern bay.

In the soffit of the architrave are sunk panels of various patterns, the
six-armed cross occurring twice. The beadings of the fasciae are
enriched with the designs commonly known as 'rope,' 'bead-and-reel,'
'egg-and-dart,' and again 'bead-and-reel.'

The frieze is in two heights. The lower portion is a semicircular
pulvinar adorned with acanthus leaves, deeply undercut; the upper
portion is occupied by a long inscription in raised ornamental letters
to the honour of Justinian, Theodora, and S. Sergius. The cornice is
decorated with dentils, 'bead-and-reel,' projecting consols,
'egg-and-dart,' and leaves of acanthus.

The inscription (Fig. 20) may be rendered thus: Other sovereigns,
indeed, have honoured dead men whose labour was useless. But our
sceptred Justinian, fostering piety, honours with a splendid abode the
servant of Christ, Creator of all things, Sergius; whom nor the burning
breath of fire, nor the sword, nor other constraints of trials
disturbed; but who endured for the sake of God Christ to be slain,
gaining by his blood heaven as his home. May he in all things guard the
rule of the ever-vigilant sovereign, and increase the power of the
God-crowned Theodora