Class Mammalia Linnaeus, 1758 - mammals Subclass Theria Parker & Haswell, 1897 Infraclass Eutheria Gill, 1872 Cohort Ferungulata Superorder Mesaxonia (Marsh, 1884) Order Perissodactyla Owen, 1848 - odd-toed ungulates Suborder †Ancylopoda Cope, 1889 see Superfamily Chalicotherioidea Gill, 1872 Family †Chalicotheriidae Gill, 1872