CUSPID ARIA. 259 



show the hinge, but it is provisiouully referred to LiopistJia on account of its 

 external resemblance to some species of that genus. ^ It should lie noted, how- 

 ever, that it is also similar to some species which are believed to belong to the 

 genus PJioladomi/a." 



Bisty'ihuflo)!. — Red Limestone of Hunstanton. 



i^'rt)«/Z//— CUSPID ARIID.E, DalL 



Genus — CaspiDAiMA, G. D. Nardo, 1840. 

 (' Anu. Sci. Lombardo-Veueto,' vol. x, p. 49.) 



CuspiDAKiA SAiiAUDiANA (Firfcf find Camjnclie), 186-i. Plate XLIII, fig. 6o,h; 



Plate XLIV, fig. Sn,l. 



1864. NE^ffiiEA Sabaudiana, F. J. Pidet and G. Campiche. Foss. Terr. Cret. Ste. 



Croix (Mater. Pal. Suisse, ser. 4), 

 p. 40, pi. e, figs. 5 — 7. 



Descnptioii. — Shell inflated, oval, oblique, slightly inequivalve, anterior part 

 sloping rapidly to the uiargin, posterior ])art compressed and produced into a 

 pointed beak. Anterior margin rounded ; ventral margin convex, curving upwardsi, 

 and passing gradually into the posterior margin. Umbones curved inwards and 

 slightly backwards. A narrow postero-dorsal area is bent at an angle Avith the 

 sides of the shell, and is limited by a carina. 



Ornamentation consists of strong, concentric ribs, most of which are con- 

 tinued on to the posterior beak, where they become rather smaller and closer 

 together ; on the sides of the ribs and in the furrows are ii few faint concentric 

 lines. Length 14 mm.; height H mm. 



AMiiifies. — This species is more inflated, the anterior part is more rounded, 

 and the concentric riljs are stronger than in C. jiitlchra (Sowerby). 



T]ipe. — From the Gault of the Perte-du-Rhone. 



Distnbntion. — Lower Gault of Folkestone. 



1 See, for example, Stoliczka, ' Crot. Fauna S. India,' vol. iii (1870), pi. ii, figs. 10, 11 ; Moesch, 

 ' Men. Pholadomyen ' (1874), pi. xxxv, fig. 5; Geinitz, 'Das Elbthalgeb. iu Sachseu ' (' Palaeonto- 

 gi-aphica,' vol. XX, pt. 2, 1873), pi. xix, figs. 6,7; Wcller. 'Crct. Pal. New Jersey,' vol. iv (1907). 

 pi. Iviii, figs. 3 — 9. 



- E.g. P. suhdmengig (d'Orbigny), 'Pal. Franc. Terr. Cret.,' vol. iii (1844), p. 38, jd. eel, figs. 

 1—3, and ' Prodr. de Pal.,' vol. ii (1850), p. 1-57. 



