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SMITHSONIAN MISCELLANEOUS COLLECTIONS. 



■ 219 - 



MONOGRAPHS 



D I P T E E A 



NORTH AMERICA. 



PART IT. 



PREPARED FOR THE SMITHSONIAN INSTITUTI 



ON 



BY 



R. OS TEN SACK EN 



WASHINGTON: 

 SMITHSONIAN INSTITUTION. 



JANUARY, 



xxxxoi. 



