JVo. 4. 



MONOGRAPH Y 



OF THE 



FAMILY UNIONID^E, 



OR NAIADES OP LAMARCK, 



(FRESH WATER BIVALVE SHELLS,) 



NORTH AMERICA, 



ILLUSTRATED BY FIGURES DRAWN ON STONE FROM NATURE. 



BY T. A. CONRAD, 



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

 THE GEOLOGICAL SOCIETY OF PENNSYLVANIA. 



PHILADELPHIA: 



J. DOBSON, 108 CHESNUT STREET. 



BOSTON: PERKINS & MARVIN.— PITT8B URGH: JOHN I. KAY & Co.- 



LONDON: O. RICH, No. 12, RED LION SQUARE.— PARIS: ARTHUS 



BERTRAND, FILS, RUE HAUTEFEUILLE No. 23- HAMBURGH: 



PERTHES & BESJER, No. 22, AM JUNGFERNSTIEG. 



E. G. DORSEY, PRINTER. 



March 1836. 



