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 Amphibia Linnaeus, 1758 - amphibians see Class Amphibia Gray, 1825 Order Nantes Linnaeus, 1758 Genus Petromyzon Linnaeus, 1758 Petromyzon branchialis Linnaeus, 1758 see Lampetra fluviatilis (Linnaeus, 1758)