They are all churches of considerable size; S. Mary Diaconissa and S. Theodosia being indeed large. They are characterised by the use of the ambulatory and domed cross plans. The carving is coarse and the capitals are of the clumsy Byzantine Corinthian type. The dome is raised on a high drum in S. Mary Pammakaristos and S. Mary Panachrantos, though this may be a later addition. The domes of the other three churches seem to be Turkish. S. Mary Pammakaristos and the south church in S. Mary Panachrantos are identical in plan with S. Andrew in Krisei, and it would be possible to date them earlier had we any evidence whatsoever. Unfortunately both have been very much altered.
S. Theodosia, S. Mary Diaconissa, and SS. Peter and Mark, taken in this order, form a series showing the gradual disappearance of the galleries and the evolution of the domed cross church into the 'four columned' church of the next period.
The Myrelaion (919-945), if the present church is of that date, is an unusually early example of this four-columned type. It is generally considered that this plan type dates at the earliest from the eleventh century. There is, however, no reason to believe that the church was rebuilt later; it is a perfectly normal example of its class, and nowhere is an early example more probable than in Constantinople. The Myrelaion may accordingly be taken as marking the commencement of the late Byzantine period in Constantinople.
The churches are now smaller; the gynecaeum, where present, is placed over the narthex; the use of patterning in the brickwork of the exterior, which occurs in some of the Basilian churches (_e.g._ the cornice of S. Theodosia), now becomes important, and alternate coursing in brick and stone is used with great effect. From this time onwards narthexes were frequently added to the existing churches.
S. Saviour Pantokrator (1118-1143 A.D.) is the largest late church in Constantinople, and is an unusually large church of its type. S. Saviour Pantepoptes (1081-1118), S. Theodore, and S. John in Trullo, belong to the same class. The last, with its circular dome and apse, is probably the latest of the three. S. Thekla (1057-1059) and Bogdan Serai are examples of hall churches of the same period.