This fossil is a partial skull of an Oreodont. You can see the teeth and the front half of the skull. The fossil measures approximately 6"x4"x2 3/4".
The extinct Oreodont is a sheep-sized, hoofed mammal that lived in North America from 40 million to 5 million years ago. They looked like a mix of a pig, a sheep, and a camel, and their name means "mountain teeth" because their flat molars looked like small mountain ranges. Many of these fossils were found in South Dakota, Nebraska, and Wyoming.
