Another Egyptian characteristic, also ascribed to Babylonian influence, is the custom of extended burial with mummification, which only begins to be met with during the Third and Fourth Dynasties. Since the dead are portrayed on the Stele of the Vultures as arranged in the extended position beneath the burial-mound,[11] it was formerly assumed that this was the regular Sumerian practice; and the contracted forms of burial, which had been found at Warka, Mukayyar, Surghul, Niffer and other Babylonian sites, were usually assigned to very late periods. The excavations at Fâra and Abû Hatab have corrected this assumption, and have proved that the Sumerian corpse was regularly arranged for burial in the contracted position, lying on its side.[12] The apparent exception to this rule upon the Stele of the Vultures may probably be regarded as characteristic only of burial upon the field of battle. There it must often have been impossible to furnish each corpse with a grave to itself, or to procure the regular offerings and furniture which accompanied individual interment. The bodies were therefore arranged side by side in a common grave, and covered with a tumulus of earth to ensure their entrance into the under world. But this was clearly a makeshift form of burial, necessitated by exceptional circumstances, and was not the regular Sumerian practice of the period.[13] Whatever may have given rise to the Egyptian change in burial customs, the cause is not to be sought in Babylonian influence. A further point, which has been cleared up by recent excavation on early Babylonian sites, concerns the crenelated form of building, which was formerly regarded as peculiarly characteristic of Sumerian architecture of the early period and as having influenced that of Egypt. It is now known that this form of external decoration is not met with in Babylonia before the period of Gudea and the kings of Ur. Thus, if any borrowing took place, it must have been on the Babylonian side. The employment of brick as a building material may also have been evolved in Egypt without any prompting from Babylonia, for the forms of brick employed are quite distinct in both countries. The peculiar plano-convex brick, which is characteristic of early Sumerian buildings, is never found in Egypt, where the rectangular oblong form was employed from the earliest period.[14] Thus many points of resemblance, which were formerly regarded as indicating a close cultural connection between the two countries, now appear to be far less striking than was formerly the case.[15] Others, again, may be explained as due to Egyptian influence on Babylonian culture rather than as the result of the reverse process. For example, the resemblance that has been pointed out between Gudea's sculpture in the round and that of the Fourth Dynasty in Egypt may not be fortuitous. For Gudea maintained close commercial relations with the Syrian coast, where Egyptian influence at that time had long been effective.