The Rock-dwellers 



This is the best edible clam at Vancouver. It is the "Oregon 

 clam" of the Portland markets. The shell is chalky, with upturned, 

 concentric ridges, dingy, or yellowish white. The lining is always 

 white and china-like. 



Habitat. — Aleutian Islands to Monterey Bay. 



S. Nuttallii, Conr., is roughened by concentric ridges, and 

 is coarse and dingy outside. Young ones have brown markings 

 on the beaks, and purple stains inside the shell. Adults have a 

 peculiar, clear, agate-like shell structure bordering the large, 

 rubbery ligament. Length, 4 to 5 inches. 



Habitat. — San Francisco to San Diego, Cal. 



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