PL AGIOD OX. 



71 



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 o 



c 



be 



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V. SUBGENUS PLAGIODON. 1 



SUBKOTUND. 



*isocardioides. Zea. H. Adams. 



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

 319, and 06s. on the Genus Unio, vol. vi. 



