Kingdom Animalia Linnaeus, 1758 - animals
   Phylum Craniata Linnaeus, 1758 see Subphylum Vertebrata Cuvier, 1812
     Class Mammalia Linnaeus, 1758 - mammals
       Subclass Theria Parker & Haswell, 1897
         Infraclass Placentalia Owen, 1837 see Cohort Placentalia Owen, 1837
           Order Cetacea Brisson, 1762 - whales, dolphins, and porpoises see Infraorder Cetacea Brisson, 1762
             Suborder Mysticeti Cope, 1891 - baleen whales see Parvorder Mysticeti Cope, 1891
               1 Family Balaenidae Gray, 1821 - right whales
               2 Family Balaenopteridae Gray, 1864 - rorquals
               3 Family Eschrichtiidae Ellerman & Morrison-Scott, 1951 - gray whales
               4 Family Neobalaenidae Gray, 1873 - pygmy right whales