PECTUNCULUS. 67 
Affinities. —This is similar to P. sublevis, Sowerby, but is smaller, proportion- 
ately less convex, and with less prominent umbones. 
Remarks.—Three specimens from the Lower Greensand of Upware, which 
were referred by Keeping (vide supra) to Pectunculus marullensis (and are 
preserved in the Woodwardian Museum), seem to differ from that species in 
having a subquadrate outline and more prominent umbones; the surface of the 
shell in those specimens is worn, and it is consequently impossible to compare 
satisfactorily the ornamentation. One example shows the hinge, but, unfortu- 
nately, very indistinctly ; so far as I can see, the lateral teeth appear to be like 
those of Cucullxa rather than Pectuinculus. 
Types.—From the Neocomian of Marolles. 
Distribution.—Ferruginous Sands (upper beds) of Shanklin. 
2. Upper Cretaceous Species. 
PrcrunxcuLus susLzvis, Sowerby, 1824. Plate XIV, figs. la—c, 2a, b, 3a—d, 
4 a—e, 5 a—e, 6, 7. 
1824. Prcruncutus susL«£vis, J. de C. Sowerby. Min. Conch., vol. v, p. 112, 
pl. eceelxxii, fig. 4. 
1850. -- — A, d’ Orbigny, Prodr. de Pal., vol. ii, p. 163 (partim). 
1854. _— — J. Morris. Cat. Brit. Foss., ed. 2, p. 220. 
1868. -= — A, Briart and F. L. Cornet. Descript. de la Meule 
de Bracquegnies (Mém. Cour. et Mém. des 
Sav. étrangers, Acad. Roy. Belg. (vol. xxxiv), 
p. 61, pl. v, figs. 21—23. 
P? 1883. —- _ W. Keeping. Foss., &c., Upware and Brickhill, 
p. 115, pl. v, fig. 9. 
Non 1837. — _ A. Goldfuss. Petref. Germ., vol. ii, p. 160, pl. 
exxvi, fig. 3. 
— 1813. = -- H. B. Geinitz. Die Verstein. ven Kieslingswalda, 
p. 14, pl. ii, figs. 19—21. 
— 1846. — — A. £. Reuss. Die Verstein. der bohm. Kreide- 
format., pt. il, p. 9, pl. xxxv, 
figs. 10, 11. 
— 1847. -= —- J. Miller. Mon. Petr. der Aachen. Kreidef., 
pun ds: pi Lvs 
?— 1883. — = FI. Schrider. Zeitschr. der Deutsch.  geol. 
Gesellsch., vol. xxxiv, p. 274. 
Description.—Shell stout, convex, longer anteriorly than posteriorly, but 
sometimes nearly equilateral; outline rounded or somewhat subquadrate ; usually 
a little longer than high. Antero-dorsal part compressed, with a rounded 
