Class Reptilia Linnaeus, 1758 - reptiles
Subclass Archosauria Cope, 1869
see Division Archosauria Cope, 1869
Order †Ornithischia Seeley, 1887
1 Suborder †Ornithopoda Marsh, 1871
see Infraorder Ornithopoda Marsh, 1881
2 Suborder †Stegosauria Marsh, 1877
see Infraorder Stegosauria Marsh, 1877
3 Suborder †Ankylosauria Osborn, 1923
see Infraorder Ankylosauria Osborn, 1923
4 Suborder †Ceratopsia Marsh, 1890
see Infraorder Ceratopsia Marsh, 1890