The ancient Sumerian deity Isimud was commonly portrayed with two faces facing in opposite directions. Sumerian depictions of Isimud are often very similar to the typical portrayals of Janus in ancient Roman art. Unlike Janus, however, Isimud is not a god of doorways. Instead, he is the messenger of Enki, the ancient Sumerian god of water and civilization. Reproductions of the image of Isimud, whose Babylonian name was Usimu, on cylinders in Sumero-Accadic art can to be found in H. Frankfort's work "Cylinder seals" (London 1939) especially in plates at p. 106, 123, 132, 133, 137, 165, 245, 247, 254. On plate XXI, c, Usmu is seen while introducing worshippers to a seated god.