Stegoceras

Stegoceras (/stɛɡoʊsɛroʊs/ "horned roof") is a genus of plant-eating pachycephalosaurid dinosaurs that lived in what is now North America during the Late Cretaceous period.

Etymology
The generic name, Stegoceras comes from the Greek stego-/στεγο- meaning 'roof' and ceras/κέρας meaning 'horn', therefore, Stegoceras means horned roof.

Description
Stegoceras had an estimated length of up to 2 metres (6.6 ft)[1] and weighed 10 kilograms (22 lb) – 40 kilograms (88 lb).[2] It had a relatively large brain that was encased in a dome of 3 inches (7.6 cm) of thick bone divided into two parts.[3] The dome had a fairly smooth surface, but was irregularly pitted by foramina which gives an entrance to channels within the bone. Stegoceras (at least S. validum) can be distinguished by having a prominent parietosquamosal shelf with open supratemporal fosse, incipient doming of the frontopariental and minute node in clusters on postorbital and squamosals.[4] Stegoceras had rounded eye sockets that faced forward, which suggests it had good vision and was thus capable of binocular vision. The teeth are small and curved with serrated edges. The head was supported by an "S"- or "U"-shaped neck.[5] When a partial skeleton of Stegoceras was first discovered, it was thought to have gastralia, or belly ribs, not typically found in other ornithischian dinosaurs. They were subsequently found to be ossified tendons.[6] The legs were more than three times the length of the arms.