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 Grallae Linnaeus, 1758
             Genus Struthio Linnaeus, 1758
               1 Struthio camelus Linnaeus, 1758 - ostrich
               2 Struthio casuarius Linnaeus, 1758 see Casuarius casuarius (Linnaeus, 1758)
               3 Struthio americanus Linnaeus, 1758 see Rhea americana americana (Linnaeus, 1758)
               4 Struthio cucullatus Linnaeus, 1758 see Raphus cucullatus (Linnaeus, 1758)