55 
CARBITA lunulata. 
TAB. CCXXXIL —Figs, i & 2. 
Spec. Char. Rhomboidal, pointed, gibbose, trans- 
versely costated ; anterior part separated by a 
projecting serrated keel ; lunette deeply exca- 
vated ; beaks involute. 
Anteriorly this shell is pointed, and the beaks also 
project considerably, so that the general outline is an 
acute rhomb ; the posterior side is rounded, and has an 
incurved edge about the confines of the lunette, which is 
very deeply impressed beneath the involute beaks; the 
anterior side is divided into several portions by slight ele- 
vations, or steps, the first of which is rather concave, 
forming a kind of truncation at the margin. There 
appear to be two teeth in the right valve, and one that 
locks between them in the left, immediately within the 
beaks : but distant teeth, if such ever did exist, are obli- 
terated in the individual before us ; the edge is toothed 
within. 
A very extraordinary species named by Mr. Miller, in 
whose cabinet the specimens described are preserved ; 
they were found at D undry. There is a strong resem- 
blance between it and Cardium retusum of Linneus, ob- 
served by Mr. Miller, but the resemblance is only 
general. I have seen the same species found in the infe- 
rior Oolite at Bayeux, in Normandy, by my highly 
valued friend Mr. De Gerville. Figs, 2, 2, give two 
views of the left valve. 
