yf..^' ^y^^cfv /^' 



OBSERVATIONS 



GENUS UNIO, 



TOGETHER Willi 



DESCRIPTIONS OF NEW SPECIES IN THE FAMILY UNIONIDiB 



KEAU BEFORE THE ACADEMY OF NATURAL SCIENCES OF PHILADELPHIA AND 

 PUBLISHF,D IN THEIR JOURNAL. 



ISAAC LEA, LL. D., 



VIUK PEES. ACAD. NAT. SCX. ; MEM. OK THE AM. PHIL. SOC. ; OF THB ZOOL. SOC. 

 or LONDON : OP THE IMPERIAL .SOC. OF MOSCOW, kC. tC. 



WITH THIRTEEN PLATES. 



VOL. VI. 

 PART I. -1857. 



PHILVUELPHIA: 



PRINTED FOR THE AUTHOR. 



MEnRIBEW t TnOMPSON PRIXTER8. 





