Mr. Mantin’s Account of fome Species of Fofil Anomia. 45 
D Es Cm 1... ON, 
ANoMIA (cufpidata), tefta conica fulcata: valvula altera con- 
‘vexa, nate incurvata: altera hires magno foramine tri- 
gonali, Tab. 3. 
Sharp-pointed conical Anomia. 
The general figure of this fhell is conical. 
The deaked or under valve, as it is ufually called, is convex, broad. 
(its greateft extent being from fide to fide), and wrought with lon- 
gitudinal ribs, which are clofely fet, thick, prominent, and croffed 
by a few flight concentric wrinkles, marking, apparently, the 
growth of the fhell. | _ The middle tib is much’ larger than the reft, 
forming a high convex ridge down the centre of the valve, increafing 
in breadth from the beak to the margins, which in that part are 
undulated or waved. The number of ‘ribs, including the middle 
one, about twenty-nine. wa beak is {mall ay and curved 
over the hinge. A 
The hinge lies, ona, perfect. firaight ne extending ia whole 
breadth: of the fhell. ) 
The upper valve is pyramidal; paleo op tapering pa: a dane 
bafe, formed by, the other yalve, toa fine point or apex, which is 
the. centre or middle part | of. the valve produced and acuminated. — 
The back, or that portion of the pyramid proceeding ftom the mar- 
gins, is rounded, longitidinally’ ribbed, and indented with a deep 
concave groove or /i/eus, correfpondent to the ridge in the under 
valve. The groove and, ribs: are, crofled by a few {trong but diftant. 
wrinkles, The frost,’ or|that part avhich; extends, from, the hinge to: 
the apex, is flat, fmooth, and perforated; in figure it nearly ap- 
proaches to an equilateral triangle. The perforation is) very large’; 
it runs through the middle of this fide of the valve, and tefembles 
6 a long 
