Classification 



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Class I. 

 Class II. 



Subclass 



Order 

 Order 



Subclass 



Order 

 Order 



Class III. 



Class IV. 



PHYLUM VIII. ANNELIDA 



Archiannelida ( 

 Chaetopoda ( 

 I. Polychaeta ( 



1. Phanerocephala ( 



2. Cryptocephala ( 



II. Oligochaeta ( 



1. Microdrili ( 



2. Macrodrili ( 



Hirudinea ( 

 Onycophora ( 



PHYLUM IX. MOLLUSCA 

 Class I. Amphineura ( 



Order 1. Polyplacophora ( 

 Order 2. Aplacophora ( 



Class II. Gastropoda ( 



Subclass I. Streptoneura ( 



Order 1. Aspidobranchia ( 

 Order 2. Pectinibranchia ( 



Subclass II. Euthyneura ( 



Order 1. Opisthobranchia ( 

 Order 2. Pulmonata ( 



Class III. Scaphopoda ( 

 Class IV. Pelecypoda ( 



Order 1. Protobranchia ( 



Order 2. Filibranchia ( 



Order 3. Eulamellibranchia ( 



Order 4. Septibranchia ( 



Class V. Cephalopoda ( 



Order 1. Tetrabranchia ( 

 Order 2. Dibranchia ( 



