152 MOLLUSCA FROM THE CRAG. 



1. CARDIUM ECHINATUM, Lmnceus. Tab. XIV, fig. 3 a b. 



Bonanni. Eecr. Ment. et Ocul., fig. 90, 1684. 

 Lister. Hist. Conch., lib. iii, fig. 161, 1687. 

 Dale. Hist, and Antiq. of Harwich, p. 292, t. xii, fig. 6, 1730. 

 CARDIUM ECHINATUM. Linn. Syst. Nat., ed. 12, No. 79, p. 1122, 1767. 

 Dacostq. Brit. Conch., p. 176, t. xiv, fig. 2, 1778. 



Miiller. Zool. Danica, t. xiii, figs. 1 and 2, and t. xiv, figs. 14. 



Donovan. Brit. Shells, t. 107, fig. 1, 1802. 

 Chemn. Conch. Cab,, vol. vi, p. 165, t. xv, fig. 158. 

 Brown. Illust. Brit. Conch., pi. xxi, fig. 6, 1827. 

 IBasterot* Bord. Foss., p. 82, 1825. 



Phil. En. Moll. Sic., vol. i, p. 49, and vol. ii, p. 37. 

 Forbes. JSgean Invert. Rep., Brit. Assoc., p. 180, 1843. 

 Loven. Ind. Moll. Scand., p. 35, 1846. 



Alder. Catal. Moll. North, and Durh., p. 83, 1847. 



Forbes and Hanley. Hist. Brit. Moll., vol. ii, p. 7, pi. xxxiii, fig. 2, 

 and pi. N, fig. 3, 1849. 



MUCRONATUM. Poli. Test. Sicil., vol. i, p. 60, pi. xvii, figs. 4, 5, 1792. 



SPINOSUM. Sowerby. Brit. Miscel., t. xxxii. 



Encyc. Method., t. 298, fig. 3. 



Spec. Char. Testa orbiculato-cordatd, convexd, sub-cequilaterali ; antice rotundatd, 

 postice sub-quadratd ; costis 19 20 convexis.papittiferis, interstitiis concentrice striatis. 



Shell orbicularly heart-shaped, convex, slightly inequilateral, anterior side rounded, 

 piosterior angular, or sub-quadrate; ribs 19 20, rounded and papilliform, interstices 

 marked by concentric striae. 



Diameter, 1^ inch. 



Localities. Red Crag, Sutton. 



Uddevalla. 



Recent, ^Egean, Mediterranean, Britain, Scandinavia. 



A very few specimens only of this shell have as yet come under my observation, 

 and those are such as have not the spines or tubercular ornaments of the ribs in a 

 perfect condition. 



The hinge is furnished with strong and prominent teeth, those called lateral are 

 nearly equidistant from the umbo, and there is a somewhat broad and prominent fulcrum 

 for the support of the ligament ; the posterior side is truncated or angular ; the bend 

 which is at the posterior lateral tooth forms an angle of about 100, and the lines of the 

 ribs are distinctly visible in the interior. Upon the younger portion of the shell the 

 tubercles are generally gone, and in the fossil that part has lost the outer portion of 

 the shell, consequently its ornament. The spaces between the ribs, which are broad 

 and flat, are nearly as wide as the ribs themselves ; they are covered with ridges or 

 elevated lines of growth at nearly regular distances. 



The figure by Dale is, I presume, of a specimen of this species, more especially as 

 he refers to Lister's representation of C. echinatum, and although in my researches 



