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 Mammalia Linnaeus, 1758 - mammals Quadrupedia Linnaeus, 1758 see Class Mammalia Linnaeus, 1758 Order Bruta Linnaeus, 1758 Genus Trichechus Linnaeus, 1758 - manatees Trichechus Manatus Linnaeus, 1758 - Caribbean manatee