(Sims, 1994)

Protoceratops -described by Granger and Gregory, 1923 (Dodson, 1996). Protoceratops is "characterized by the lack of horns, the very large size of the orbits, and the narrowness of the postorbital-squamosal bar." (Dodson, 1996). As in Leptoceratops, the nasal is smaller than any other known ceratopsian. In mature skulls it begins to arch up forming an incipient horn-core. It is thought that the arching of the nasal represents the earliest stage in the development of nasal horn cores. The small Protoceratops is found equally in North America and Asia (Dodson, 1996). Even though it possesses only the most rudimentary headgear, it presumably includes the ancestors of the ceratopsids (Dodson, 1996).