CHAPTER VI 



CKUSTACEA 



Phylum TROCHOZOA 



Sub-Phylum ARTICULATA 

 Division ARTHROPODA 

 Class 

 CRUSTACEA Land, fresh water, sea. 



Type, Nephrops. 

 TRILOBITA Extinct, sea. 



MEROSTOMATA 

 "XIPHOSURA Sea. 



EURYPTERIDA Extinct, fresh water, sea. 

 PYCNOGONIDA Sea. 

 ARACHNIDA Land, fresh water, sea. 



TARDIGRADA Fresh water, sea. 



PROTOTRACHEATA Land. 

 MYRIOPODA Land. 



INSECT A Land, fresh water, and 



rarely sea. Type, Blatta. 



WE have reason to believe that the Annelida have an 

 ancient history, but the hard skeletons of the Mollusca and of 

 the Articulata which have been preserved in the formations 

 show that many of the classes of the Trochozoa were in 

 existence at the dawn of palaeontological history. 



The Annelida have segmented bodies. The Arthropoda 

 have segmented bodies and segmented limbs. 



Nephrops. The Norway lobster, also sometimes called 

 the * crayfish ' and the ' prawn/ is very common in the deep 

 water a few miles from the coast in several parts of the North 

 Sea, Irish Sea, etc. It is common on the coast of Norway, 



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