SMITHSONIAN INSTITUTION 



UNITED STATES NATIONAL MUSEUM 

 Bulletin 122 



A MONOGRAPH OF THE AMERICAN 



SHIPWORMS 



BY 



PAUL BARTSCH 



Curator, Division of Mollusks, United States National Museum 





PER\ 



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.'VV^.SO'^IAN 7^?^ 



WASHINGTON 

 GOVERNMENT PRINTING OFFICE 



1922 





IBSUiLU 



AUG -4 19 



