CRUSTACEA 



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CLASSIFICATION OF CEUSTACEA. 



Thoracica. 



I 



Pedunculata. 

 Operculata. 



Thyrostraca (Cirripedia). 



Orders. 

 Abdominalia. Apoda. 



Khizocephala. 



Podophthalma, or Stalk -eyed Crustacea. In the 

 Brachyura, or crabs, the male is usually much larger than 



