Vertebrata Cuvier, 1812 - vertebrates Gnathostomata Teleostomi Tetrapoda Hatschek & Cori 1896 [Gauthier, Kluge & Rowe 1988] Amniota Haeckel, 1866 [Gauthier, Kluge & Rowe 1988] - amniotes Class Mammalia Linnaeus, 1758 - mammals Subclass Theria Parker & Haswell, 1897 Theria of Metatherian-Eutherian grade Infraclass Metatheria Huxley, 1880 [monotypic] 1 Order Marsupialia Jameson, 1818 - marsupials see Cohort Marsupialia Jameson, 1818