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
         1 Class Mammalia Linnaeus, 1758 - mammals
         2 Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
         3 Class Amphibia Linnaeus, 1758 - amphibians see Class Amphibia Gray, 1825
         4 Class Pisces Linnaeus, 1758 see Superclass Pisces Linnaeus, 1758
         5 Class Insecta Linnaeus, 1758 - insects
         6 Class Vermes Linnaeus, 1758 - worms see Phylum Vermes (C. Linnaeus, 1758)