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Phylum Sipunculoidea 

 Mollusciformes 



Phylum Mollusca 

 Vermes 



Phylum Annelida 



Subphylum Archiannelida 

 Subphylum Poiychaeta 

 Subphylum Oligoch^ta 

 Subphylum Echiuroidea 

 Subphylum Myzostomida 

 Subphylum Hirudinea 

 Subphylum Onychophora {Peripatus, etc.) 

 Osteozoa 

 A no ma li forme s 



Phylum Nemertea 

 Phylum Phoronida 

 Phylum Brachiopoda 

 Phylum Chaetognatha 

 Articulata 



Phylum Echinodermata 

 Phylum Arthropoda 

 Enteropneusta 



Phylum Pterobranchia 

 Phylum Balanoglossida 

 Vertebratoidea 

 Acraniata 



Phylum Tunicata 

 Phylum Gephalochorda 

 Craniata 



Phylum Vertebrata. 



