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 Gallinae Linnaeus, 1758 Genus Tetrao Linnaeus, 1758 Tetrao perdix Linnaeus, 1758 see Perdix perdix (Linnaeus, 1758)