With the disjunctive plan Mesopotamian archaeology is not concerned; nor do I believe that the conjunctive plan was either widely or permanently of importance, at any rate up to the period to which Ukhaiḍir belongs. The Greek scheme cannot be brought into sharper contrast with the Mesopotamian than by laying a plan such as that of the Pergamene palace (Fig. 17) beside a plan such as that of the smaller palace at Niffer (Fig. 9). I select with intention a building wherein Hellenism has influenced the details, but left the fundamental principle unchanged. At Pergamon the court results from the manner in which the isolated chambers are placed and linked together; at Niffer a court remains over from the manner in which the chambers or groups of chambers are placed within, and linked to, the encompassing wall. In the baits of Ukhaiḍir it is no less the encompassing wall which is the indispensable essential, and it may even be surmised that the latitudinal chamber which lies behind the lîwân is a survival of the intentional separation of the principal room from the wall. But it is not only the bait, the unit, which must be considered, it is the grouping of units. Now these units are so placed round the encompassing wall, and joined together in such fashion, as to leave a court over. In detailed and in general disposition Ukhaiḍir exhibits the injunctive plan. Before considering the Umayyad ḥîrahs of the western desert three other Sasanian buildings must be passed briefly under review. I will deal first, though it is not first in date, with the second palace at Qaṣr-i-Shîrîn, Chehâr Qapû.