CHAPTER VI 



THE MALACOSTRACA 



Sub-Class Malacostraca, Latreillc (180G). 

 Series I. Leptostraca. 



Division Phyllocarida. 

 Order Nebaliacea. 



Series II. Eumalacostraca. 

 Division 1. Syncarida. 

 Order Anaspidacea. 



Division 2. Peracarida. 

 Order 1. Mysidacea. 



C' 



Definition. — Crustacea in which the carapace is variously 

 developed or may be vestigial ; there are typically fourteen (rarely 

 fifteen) trunk - somites, all of which (except the fifteenth) bear 

 appendages ; the telson rarely has a caudal furca ; antennules often 

 biramous ; the mandibles may have a palp ; the trunk-limbs are 

 differentiated into two tagmata, a thoracic of eight and an 

 abdominal of six pairs ; female genital apertures on the sixth, 



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