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ALLAN HANCOCK PACIFIC EXPEDITIONS 



VOL. 20 



Fig. 45. 



My fella falcata (Orbigny). Distribution mainly according 

 to sample in American museums. 



Fig. 46. Arcuatula demissa (Dillwyn). New London Bay, Gulf of 

 St. Lawrence. Anterior retractor in the umbonal cavity, a 

 small scar between the anterior adductor and retractor 

 scars. 



