"global chronostratigraphic units"
   (Eon) Phanerozoic Eon (541.0 Ma - present)
     (Era) †Paleozoic Era (541.0 - 251.902 Ma)
       (Period) †Carboniferous Period (358.9 - 298.9 Ma)
         (Subperiod) †Pennsylvanian Sub-period (323.2 - 298.9 Ma)
           1 (Epoch) †Bashkirian Epoch see Age Bashkirian Age (323.2 - 315.2 Ma)
           2 (Epoch) †Moscovian Epoch see Age Moscovian Age (315.2 - 307.0 Ma)
           3 (Epoch) †Kasimovian Epoch see Age Kasimovian Age (307.0 - 303.7 Ma)
           4 (Epoch) †Gzelian Epoch see Age Gzhelian Age (303.7 - 298.9 Ma)