Natura - nature
   actualia - actual entities
     Mundus Plinius - physical world
       Astra Plinius - celestial bodies
         Universe
           (Supercluster) Virgo-Hydra-Centaurus Supercluster
             (Supercluster) Virgo Supercluster
               (Cluster) Local Group
                 (Galaxy) Milky Way Galaxy veter.
                   (Spiral arm) Orion Arm
                     (Region) Local Bubble
                       Local Interstellar Cloud
                         (Planetary system) Solar System
                           (Planet-satellite system) Earth System
                             (Planet) Earth veter.
                               "spheres" (Earth)
                                 (Sphere) Biosphere (Earth) - zone of life
                                   "floristic regions"
                                     Holarctic Kingdom
                                       Boreal Subkingdom
                                         Circumboreal Region
                                           01 Arctic Province
                                           02 Atlantic-European Province
                                           03 Central European Province
                                           04 Illyrian Province
                                           05 Euxine Province
                                           06 Caucasian Province
                                           07 Eastern European Province
                                           08 Northern European Province
                                           09 Western Siberian Province
                                           10 Altai-Sayan Province
                                           11 Middle Siberian Province
                                           12 Transbaikalian Province
                                           13 Northeastern Siberian Province
                                           14 Okhotsk-Kamchatka Province
                                           15 Canadian Province