HIPPAGUS, Lea. 
Gem. 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, & V. Wood , MSS. 
11 I 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 4 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 Venericardia , 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 riglit 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.” 
44 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 
Enumeratio Molluscorum Sicilia: by Philippi, where a re- 
cent Mediterranean shell is described and figured ( Hip - 
pagus acuti costatus, ) 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 
