- 7'%0 - 



PHAOOiDrs ivzn::.) 3i^ov^i:i n. sp. 



Oescrj-otion*- Shell of me^lium size, moderately inflaterl, 

 saborbicular, the posterior dorsal margin being long and only 

 slightly curved a: ? posterior lateral marrin obscurely sub- 



truricateri; anterior florsal margin with a very gentle slope; ma- 

 bones lov/; posterior area v/ide, not deeply imprescpd; anterior 

 dorsal area sharply impressed; external sculpture of prominent, 

 evenly s'^^^'Cti^^ oo".'^ entric mgae over the entire surface of tl^e 

 shell. 



Dimensions .- lat., 37 mm.; alt,, 35.5 mm.; semidiara. , 

 9.5 mm. 



Remarks .- Tv/o valves, one of which is adult, form the ^as- 

 is of this species. It is characterized by its gently curved 

 pos tero-dor sal margin, lov; umbo •^^•"■' ■':'rominer:t , regular concentric? 

 sculpture; these features se^oarate it from po-lagrinus and the 

 forms with which podagrinus is compare^!. Superficially it resembles 

 more closely the recent './est Indian P. pe nnsy 1 vani c us (Linnaeus), (1) 



(1). Syst. rat., eri. 10, d. 688, 1758; Reeve, Oonch. Icon., vol. 

 6, lucina, pi. 6, fig. S9, 1850. 



which ranges back to the Plioceti.:;, uhan the other Bow den forms, 

 but it is less inflated, less orbicular and has a shorter antero- 



