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 Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758 Picae Linnaeus, 1758 see Parvclass Picae (C. Linnaeus, 1758) Psittacus Linnaeus, 1758 Psittacus rufirostris Linnaeus, 1758