Class [Mammalia] Linnaeus, 1758 - mammals Order Marsupialia Jameson, 1818 - marsupials see Cohort Marsupialia Jameson, 1818 Family Didelphidae Gray, 1821 - American opossums Genus Marmosa Gray, 1821 - murine opossums Marmosa cracens (Handley & Gordon, in Eisenberg, ed., 1979) see Marmosops cracens (Handley & Gordon, 1979)