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 Insecta Linnaeus, 1758 - insects Order Diptera Linnaeus, 1758 - true flies, mosquitoes, gnats Genus Oestrus Linnaeus, 1758 Oestrus ovis Linnaeus, 1758 - sheep bot fly