[Kingdom] Animalia Linnaeus, 1758 - animals
   Grade Enterozoa
     Grade Cœlomata
       Phylum Mollusca Linnaeus, 1758 - molluscs
         Branch Eucephala
           Grade Echinoglossa
             Class Gastropoda Cuvier, 1795 - snails and slugs
               Grade Cochlides
                 Order Cryptocochlides
                   1 Genus Aplysia Linnaeus, 1767 - seahare
                   2 Genus Eolis Cuvier, 1805, orth. inval. see Genus Aeolidia Cuvier, 1798