.^-^ 



MEMOIRS 



OF THE 



BOSTON SOCIETY OF NATURAL HISTORY. 



VOLUME II. PART IV. NUMBER I. 





PRODROME OF k MONOGRAPH OF THE TABAIID.E OF THE 



UNITED STATES. 



PART I. THE GENERA PANGONIA, CHRYSOPS, SILVIUS, 

 H.EMATOPOTA, DIABASIS. 



By C. R. OSTEN SACKEN. 



\ 



BOSTON: 

 PUBLISHED BY THE SOCIETY. 



Apeil, 1875. 



