OBSERVATIONS 



ox THE 



GENUS UNIO, 



rOaETHBB WITH 



DESCRIPTIONS OF NEW SPECIES IN THE FAMILIES UNIONIDiE, COLIMACEA 



AND MELANIANA. 



HEAD BEFORE THE AMERICAN PHILOSOPHICAL SOCIETY, AND ORIGINALLY 

 PUBLISHED IN ITS TRANSACTIONS. 



BY 



L 



ISAAC LEA, 



MEMBER OF THE AM. PHIL. SOC; OF THE ACAD. OF NAT. SCIENCES OF PHILADA.: 



OF THE ZOOL. SOC. OF LONDON; OF THE IMPERIAL 



SOC. OF MOSCOW, iC. 4C. 



WITH NUMEROUS PLATES. 



. rcr. 



VOL. V. 



PHILADELPHIA: 

 I'RINTED FOR THE AUTHOR. 



*-. 



