Ceratopsidae

Figure 9 G, H

Although worn ceratopsian teeth form a sizable portion of the ornithischian remains, they cannot be differentiated at the generic level. Unworn teeth indicate that at least two genera of ceratopsians may have been present. The ceratopsians of the Judith River Formation have been discussed by, among others, Lull and Hatcher (1907) and Lull (1933). Based mostly on fragmentary material, a number of species of Monoclonius and Ceratops, the only two genera known from the formation, have been described. Brachyceratops montanensis was described by Gilmore (1917) from the Two Medicine Formation of Montana. The Oldman Formation of Alberta has produced better known forms such as Eoceratops, Brachyceratops, Monoclonius, Centrosaurus, Styracosaurus, Chasmosaurus, and Anchiceratops (Sternberg, 1940 a; Langston, 1965, p. 4). ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 3. An unworn tooth, AMNH 8540, from Clambank Hollow, has a sharply pointed apex (fig. 9 G, H). The sides of the crown are serrated toward the apex, and a strong median keel must have been present but it is broken away in the specimen. A much larger tooth, AMNH 8541, also from Clambank Hollow, with rougher ornamentation, probably belongs to a distinct genus.