1 



MONOGRAPHY 



OF THE 



FAMILY UNIONIDiE, 



OR NAIADES OF LAMARCK, 



(FRESH WATER BIVALVE SHELLS,) 



OF 



NORTH AMERICA, 



ILLUSTRATED BY FIGURES DRAWN ON STONE FROM NATURE. 



BY T. A. CONRAD, 



CURATOR OF THE ACADEMY OP NATURAL SCIENCES OP PHILADELPHIA, HONORARY MEMBER OF 

 THE GEOLOGICAL SOCIETY OF PENNSYLVANIA. 



PHILADELPHIA: 



J. DOBSON, 108 CHESNUT STREET. 



1836. 



