Imperium naturæ C. Linnaeus, 1758 - nature
   Mundus Plinius - physical world
     naturalia - natural bodies
       Regnum Animale C. Linnaeus, 1758 - animal kingdom see Kingdom Animalia Linnaeus, 1758
         Class Vermes Linnaeus, 1758 - worms see Phylum Vermes (C. Linnaeus, 1758)
           Order Intestina Linnaeus, 1758
             Genus Hirudo Linnaeus, 1758
               1 Hirudo sanguisuga Linnaeus, 1758
               2 Hirudo medicinalis Linnaeus, 1758
               3 Hirudo octoculata Linnaeus, 1758
               4 Hirudo stagnalis Linnaeus, 1758
               5 Hirudo complanata Linnaeus, 1758
               6 Hirudo indica Linnaeus, 1758
               7 Hirudo geometra Linnaeus, 1758
               8 Hirudo muricata Linnaeus, 1758