A Pachycephalosaurus skull dug up on the Schmidt ranch dig is on display in the museum.
Pachycephalosaurus was a dome-headed dinosaur. Its huge head housed an incredibly thick skull, a tiny brain, and large eyes. Its rounded skull was up to 10 inches thick (25 cm).
Pachycephalosaurus grew to be about 15 feet long (4.6 m) and may have weighed roughly 950 pounds (430 kg). Pachycephalosaurus probably had a good sense of smell. It had bumpy knobs on its snout and along the rear of its skull. This plant-eater had short forelimbs and a stiff tail (which had a distinctive mesh of interwoven tendons surrounding its rear portion).
The Triceratops is the South Dakota state fossil. A Triceratops skull named Garth was found on the Schmidt ranch in the 1990's and is the most complete skull of that speicies in the museum.