Morrison Formation, Wyoming Jurassic Thought to be a new species, this magnificent 150-milion-year-old Stegosaurus displays two features not seen in the genus before - anchor points on the back plates and an extra bone, possibly a vestigial back plate. Measures 20 feet in length Price Upon Request

Triceratops Bowman County, North Dakota Cretaceous Affectionately dubbed, "Bob," this large Triceratops individual is astonishingly intact. "Bob" would have lived near the end of the Cretaceous, in one of the herds that were thought to have fed near the shorelines of the intercontinental seaway, which separated the western half of North America from the rest of the continent. Length measures 26 feet Price Upon Request

Hell Creek Formation, North Dakota This beautifully preserved adult Triceratops skull includes the braincase; though this feature represents an important skull component, it is not commonly seen in dinosaur specimens, augmenting the rarity of this stunning specimen. Triceratops, an iconic dinosaur genus of the North American Late Cretaceous, is thought to have lived in herds. Length measures approximately 7 feet. SOLD

Thescelosaurus sp. Late Cretaceous Hell Creek Formation, Harding County, South Dakota This ornithopod (bipedal ornithischian dinosaur) species is known from several partial skeletons and skulls. With approximately 85% of the original skeleton represented, this is one of the most complete examples of this genus known. The skeleton has been mounted on a custom metal armature attached to a hardwood base. Length measures approximately 9 feet. $350,000