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) Atmosphere (Earth) - layer of air
                                   (Phenomenon) Meteors
                                     (Phenomenon) Hydrometeors
                                       (Phenomenon) Clouds
                                         Phenomenon Middle Clouds
                                           Genus Altocumulus E. Renou, 1870
                                             01 Altocumulus stratiformis
                                             02 Altocumulus lenticularis
                                             03 Altocumulus castellanus
                                             04 Altocumulus floccus
                                             05 Altocumulus translucidus
                                             06 Altocumulus perlucidus
                                             07 Altocumulus opacus
                                             08 Altocumulus duplicatus
                                             09 Altocumulus undulatus
                                             10 Altocumulus radiatus
                                             11 Altocumulus lacunosus