The Sons of Horus were minor deities who protected the internal organs which were removed during the mummification process. These were embalmed in the same way as the body, wrapped and placed in stone or wooden jars, which were sometimes kept together in a canopic chest. Initially, the jars had plain disc lids but human-headed lids later became more common. After the late Eighteenth Dynasty (about 1550-1295 BC), the stoppers often actually represent the four Sons of Horus. Here the god Qebhsenuef (intestines) is shown with a jackal head; Duamutef (the stomach) as a falcon head; Hapy as baboon-headed (the lungs), and Imsety (the liver) with a human head. A change took place in the embalming practice during the Twenty-First Dynasty (about 1069-945 BC).The internal organs were returned to the body cavity after being wrapped, protected by wax or clay figures of the Sons of Horus. This made the canopic jars redundant, though they were still included in the tomb as they were viewed as an essential element of a good burial. The jars were often not hollowed out and were simply dummies, though as in these examples, they were decorated and inscribed as if they were intended for use.