Diplocaulus (meaning "double stalk") is and extinct genus of Lepospondyl amphibians that lived during the Late Carboniferous to Late Permian Periods (307 to 257 million years ago) in Africa (Morocco) and North America (Texas and Oklahoma). It is characterized by its distinctive boomerang shaped skull. The boomerang shape of the skull was created by elongated bones or horns that formed at the back sides of the skull.. There are several theories as to the purpose of the elongated skull. Among them are: that it provided lift (a hydrofoil) while swimming, allowing it to move more easily through the water. Secondly, that it provided protection for its gills. Thirdly, that because of its wide head, it would have been difficult for predators to swallow. Diplocaulus inhabited freshwater ponds, streams, and swamps. It was a bottom feeder and its diet probably included fish, other amphibians, and invertebrates (snails, small crustacians, and insects). Dimensions: 22" x 14" x 2-1/2"