()7 



MIPPAGUS, Lea. 



Gen. Char. Shell equivalved, cordiform, longitu- 

 dinally costated ; hinge with a subinternal 

 ligament winding up under the umbones_, and 

 one obtuse tooth which is in the right valve ; 

 fulcrum of the left valve linear, apparently 

 tubular; a lunette under the beaks. 



Syn. Verticordia, 8. V. Wood, MSS. 



1 HAVE ventured to propose a new genus for the recep- 

 tion of a shell I had with doubt placed in the genus Cryp- 

 todon in my ' Catalogue of Shells from the Crag,' and to 

 remove it from that genus in consequence of its rugosely 

 costated exterior and its internal ligament. It resembles 

 in general appearance a Fenericardia, but differs from that 

 genus in the position of the ligament and the want of so- 

 lidity about the hinge. It is further characterized by the 

 short fulcrum or portion of the hinge (in the left valve) 

 with a circular perforation or opening (at its extremity), 

 into which the ligament appears to have entered laterally 

 from the posterior side : there is a prominent obtuse tooth 

 in the right valve, with a sort of notch in the opposing one 

 for its reception ; beneath the umbones is a deep semicir- 

 cular lunette, particularly marked in the left valve; one 

 ovate muscular impression is seen in the anterior side, the 

 second impression is indistinct, the interior is smooth and 

 nacreous." 



" The generic name is one of the synonyms of the God- 

 dess of Beauty, and is also appropriate from the elegant 

 curvature of this cordiform shell." 



The above description was drawn up by Mr. S. V. Wood 

 previous to the publication of the second volume of the 

 Eiiumeratio Molhiscorum Sicilia: by Philippi, where a re- 

 cent Mediterranean shell is described and figured [Hip- 

 pagus acuticostatus) which differs only in slight specific cha- 

 racters from the subject before us ; Philippi has referred 

 this shell to the genus Hippagus of Lea, (Contributions to 

 Geology, Philadelphia 1833. p. 72. pi. 2. f 50, Hippagus 



