The Shedu is a celestial being from Mesopotamian mythology. He is a human above the waist and a bull below the waist. He also has the horns and the ears of a bull. The bull man helps people fight evil and chaos. He holds the gates of dawn open for the sun god Shamash and supports the sun disc. He is often shown on Cylinder Seals. It appears frequently in Mesopotamian art, sometimes with wings. Statues of the bull-man were often used as gatekeepers.
William Swinton Outlines of the Worlds History, Ancient Mediabal and Mondern, with special relation to the history of civilization and the progress of mankind (New York, NY: Ivison, Blakeman and Company, 1874)