12 

 AXIKUS obsc'urus. 



Spec. Char. Obovate, posteriorly cuneiform ; 

 anteriorly rounded ; surface convex, with 

 one obtuse keel ; beaks large. 



ooMEWHAT resembling" the last in form, hut not so wide, 

 and having no angles upon the anterior end ; as the 

 specimens are all casts the lunette is not observable, 

 but the impressions of the muscles and the edge of the 

 uianlle are strongly marked ; the latter is entire. 



This uncommon shell was brought to me by Mr. 

 Farey, from Garforth Cliff quarry, near Leeds, where 

 it 'was discovered by Wm. Siiiithson, Esq. and also 

 from Selby, eight miles distant, supposed to be out of 

 the Magnesian Limestone, a rock but sparingly sup- 

 plied with fossil shells. The cast enclosed in the mass 

 of stone (see the lowest figure,) may possibly be another 

 species, but it is too imperfect to decide upon. Mr. 

 Farey found it by the road-side one mile N. W. of 

 Pontefract, in a stratum 6 or 8 inches thick, probably 

 similar to another at Westbridge Hill ; it has part of 

 the shell remaining upon it. 



