Imperium naturæ C. Linnaeus, 1758 - nature
   Mundus Plinius - physical world
     naturalia - natural bodies
       Regnum Animale C. Linnaeus, 1758 - animal kingdom see Kingdom Animalia Linnaeus, 1758
         Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
           Order Anseres Linnaeus, 1758 see Suborder Anseres Linnaeus, 1758
             61 Genus Anas Linnaeus, 1758 - Pacific black duck
             62 Genus Mergus Linnaeus, 1758
             63 Genus Alca Linnaeus, 1758
             64 Genus Procellaria Linnaeus, 1758
             65 Genus Diomedea Linnaeus, 1758
             66 Genus Pelecanus Linnaeus, 1758
             67 Genus Phaëthon Linnaeus, 1758 see Genus Phaethon Linnaeus, 1758
             67.0 Genus "Phäethon" Linnaeus, 1758 see Genus Phaethon Linnaeus, 1758
             68 Genus Colymbus Linnaeus, 1758
             68.0 Genus "Columbus" Linnaeus, 1758 see Genus Colymbus Linnaeus, 1758
             69 Genus Larus Linnaeus, 1758
             70 Genus Sterna Linnaeus, 1758
             71 Genus Rynchops Linnaeus, 1758
             71.0 Genus "Rhyncops" Linnaeus, 1758 see Genus Rynchops Linnaeus, 1758