CHAPTER X 



Scallops, Oysters and 

 Other Clams 



Class PELECYPODA 



The bivalves or clams are dwellers of fresh, marine or brackish waters. 

 They lack a head and are without jaws or radular teeth; they are protected 

 by a pair of shelly valves which are connected or hinged by a horny ligament 

 and which are moved by the contraction of one to three muscles attached 

 to the inner sides of the valves; feeding is usually done with the aid of their 

 ciliated or hair-covered gills. Further details have been presented in the 

 chapter on "The Life of the Clam." The class is also known as Lmnelli- 

 branchia, Bivalvia or Acephala. The class may be divided into the follov/ing 

 orders and suborders: 



Order PALAEOCONCHA 



Suborder SOLEMYACEA (Awning Clams) 



Order PROTOBRANCHIA 



» 



Suborder NUCULACEA (Nut Clams) 



Order FILIBRANCHIA 



Suborder TAXODONTA (Ark Shells) 



Suborder ANISOMYARIA (Scallops, Oysters, Sea Mussels) 



Order EULAMELLIBRANCHIA 



Suborder SCHIZODONTA (River Mussels) 

 Suborder HETERODONTA (Cockles, Lucines, Venus) 

 Suborder ADAPEDONTA (iVlya and Razor Clams, Teredos) 

 Suborder ANOMALODESMACEA (Pandora Clams) 



Order SEPTIBRANCHIA 



Suborder POROMYACEA (Dipper Clams, Meat Eaters) 



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