Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
   Subclass Ornithurae Haeckel, 1866 see Clade Ornithurae Haeckel 1866 [Gauthier 1986] {Chiappe 1991}
     Infraclass Carinatae Merrem, 1813 see Clade Carinatae Merrem 1813 [Gauthier & de Queiroz 2001]
       Order Procellariiformes Fürbringer, 1888
         1 Family Diomedeidae Gray, 1840 - albatrosses
         2 Family Procellariidae Leach, 1820 - petrels, shearwaters
         3 Family Oceanitidae Forbes, 1882
         4 Family Pelecanoididae Gray, 1871 - diving petrels