11 



AXINITS. 



Gen. Char. A free eqiialvalved, trans v^se, 

 bivalve ; anterior side very sliort ; posterior 

 ^ide produced, truncated, with a lunette 

 near the beaks : hinge with a long oblique 

 ligament placed in a furrow. 



The regular lunette, and tl^e extremely short anterior 

 side, with the hinge cartilage extended alonj^ almost 

 the whole of its edge, seem to point out this as a 

 distinct genus, and it is much to be regretted that there 

 is very little probability of discovering the interior struc- 

 ture of the hinge, but I suspect it has no teeth. The 

 shell appears to be thin, but I can trace neither the 

 cicatrices of the muscles, nor of the edge of the mantle 

 in the angulatiis, which I consider the type of the genus. 

 The name,* and indeed the genus itself, cannot be 

 considered as well established, until more is known 

 respecting the shells included under it : a bad name is 

 however better than none. 



AXINITS ansuiatus. 



53 



TAB. 



Spec. Char. Obovate, subhexangular ; pos* 

 teriorly cuneiform, surface subbicarinated ; 

 beaks small, recurved. 



A. DEPRESSED shcll, whose greatest length is nearly 

 perpendicular to the hinge cartilage; the base (front) 

 rounded terminated at each end by an angle Irom which 

 two obtuse keels run up to the beaks ; the anterior keel 

 is sharpest, near to and almost parallel with the hinge : the 

 posterior keel is very obtuse, from it to near the lunette 

 the surface is almost flat, but just upon its border the 

 shcll rounds with an obtuse angle upon its e^^e : the 

 lunette is impressed, ovate, pointed, aud curved. 



Found in the London Clay, near the White Conduit 

 House at Islington ; and by Mr. i^ibbs in clay brought 

 up from a weU in the road irom Vauxhall to Wands- 

 worth, generally filled with Pyrites. 



*^ Taken from the hat<lier-)ike forai ol the posierior»ide. 



