Order †Pachycephalosauria Maryañska & Osmólska, 1974 see Infraorder Pachycephalosauria Maryañska & Osmólska, 1974 1 Family †Pachycephalosauridae Sternberg, 1945 2 Genus †Majungatholus Sues & Taquet, 1979 3 Genus †Yaverlandia Galton, 1971