Kingdom [Animalia] Linnaeus, 1758 - animals
   Subkingdom Metazoa Haeckel, 1874 see Kingdom Animalia Linnaeus, 1758
     Division Eumetazoa Butschli, 1910 see Subkingdom Eumetazoa Butschli, 1910
       Subdivision Bilateralia
         Phylum Chordata Bateson, 1885 - chordates
           Subphylum Vertebrata Cuvier, 1812 - vertebrates
             Class Reptilia Linnaeus, 1758 - reptiles
               Subclass Archosauria Cope, 1869 see Division Archosauria Cope, 1869
                 Order †Ornithischia Seeley, 1887
                   Suborder †Ornithopoda Marsh, 1871 see Infraorder Ornithopoda Marsh, 1881
                     Family †Hadrosauridae Cope, 1869 - hadrosaurs
                       Genus †Hadrosaurus Leidy, 1858, nom. dub.