The sedilia of the clergy. Even in cemeterial churches, celebrations supposed the collective presence of a fairly numerous clergy, for whom fixed sedilia were created at least from the 5th c. and doubtless even before. These were generally one or more benches, arranged in ascending tiers as in a theater, above footrests, and commonly called synthronos or synthronon. The bishop, who could also be provided with a throne outside the cathedral church and his episcopal city, sat on a prominently placed cathedra, higher and made of more sumptuous material, which could be integrated with the collective sedilia. The most common type was the semicircular synthronos backing onto the wall of the apse and dominated by an axial cathedra. It was much more frequent than was once thought since, when made of light material, sometimes largely of wood, it has left few traces, e.g., mere slots in the wall for beams in Cyrenaica. For a numerous clergy or when a raised chair occupied an unraised apse, the steps could reach a great height and were sometimes provided with an empty space or a service corridor which allowed circulation under the benches wellpreserved example in St. Irene, Constantinople. In Greece and neighboring regions, but also sporadically in Syria-Palestine and once in Africa Sbeitla, the steps were sometimes arranged on a rectangular plan, in front of the apse and at the sides of the altar. This rectangular type seems older than the semicircular type from the observations made both in Greece and at Sbeitla, where the two forms coexisted or succeeded each other.