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/■/////y 



OBSERVATIONS 



77^ 



GENUS UNIO, 





TOCETllEU WI 



HKSnjlJTlONS Ol' XKW SrECIK.S, TllKIll .SOFT PARTS, AM) EMBUYOXIC F(M;.MS, 1\ 

 TlIK FAMILY UNIONID.E. 



KKAO UKFOUE THK ACADIiMV OF NATURAL St•IE^•C•ES OF I'HIL.\^ELPIIIA, ANP 

 rum.ISIlKD IN THEIR JOURNAI.. 



ISAAC LEA;LL. 1). 



rUKSIIiE.NT OF TlIK ACAIlEMY OP 



A\ ITIl TWKLVK I'LATKf 



■^^. 



VOL. V.-PART I. 



rillLADELnilA : 



PRINTED FOR THE AUTHOR. 



