PLAGIODON. 



71 



V. SUBGENUS PLAGIODON. 1 



p 



o 



n 

 - 

 S 

 P 



CO 



(5 

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SUBROTUND. 



*isocardioides. Lea. H. Adams. 



1 Proposed by me, Proc. Acad. Nat. Sci., vol. viii. p. 79, and Jl. Acad. Xat. Sci., vol. iii., N. S., p. 

 319, aud Obs. on the Genus Unio, vol. vi. 



