Natura - nature
   actualia - actual entities
     Mundus Plinius - physical world
       naturalia - natural bodies
         ["Vegetabile Regnum" nom. inval. - plant kingdom] see Kingdom Plantae Haeckel (1866)
           ["Publicae"]
             ["Monoclinia"]
               ["Diffinitas"]
                 ["Indifferentismus"]
                   [Class "Icosandria" L. (1735), nom. inval.] see Class Icosandria L. (1753), nom. inval.
                     [Order "Icosandria Digynia" L. (1735), nom. inval.] see Order Icosandria Digynia L. (1753), nom. inval.
                       1 [Genus "Crataegus" Tourn., nom. inval.] see Genus Crataegus L. (1753)
                       1.0 [Genus "Oxyacantha" H.B. Ruppius, nom. inval.] see Genus Crataegus Tourn., nom. inval.