In 1912, Osborn came up with a description of the fossil and a theory to its mummification: "After a natural death (in other words, not death by predators) the body lay exposed to the sun for a long time, perhaps on a sand bar or in a stream. The muscles and soft internal tissues became completely dried and shrunken while the skin, hardened and leathery, shrank around the limbs and was drawn down along the bones. In the stomach and abdominal areas the skin was drawn within the body cavity, while along the sides of the body and on the arms, it was formed into creases and folds. At some later date, the "mummy" may have been caught in a sudden flood and carried downstream and rapidly buried in fine sand and clay. A cast, or impression, of the skin formed in the sand before the skin and other