NUCULA. 21 
Nucuta ovata, Mantell, 1822. Plate III, figs. 16—18, 19 a, b, 20, 21a, b; Plate 
IV, figs. 1 a, b. 
1822. Nucuta ovata, G. Muntell. Foss. S. Downs, p. 94, pl. xix, figs. 26, 27. 
1838. = cAapszrorMis, H. Michelin. Mém. Soc. Géol. de France, vol. iii, 
pl. xii, fig. 8, p. 102. 
1844. — ovata, A. d’Orbigny. Pal. Franc. Terr. Crét., vol. iii, p. 173, 
pl. cecil, figs. 1—3. 
1850. — — — Prodr. de Pal., vol. ii, p. 137. 
1852. = — FJ. Pictet and W. Roux. Moll. foss. des Grés verts de 
Geneve, p. 473, pl. xxxix, fig. 4. 
L854. = a J. Morris. Cat. Brit. Foss., ed. 2, p. 217. 
1866. — — FE. J. Pictet and G. Campiche. Foss. du Yerr. Crét. des 
Envir. de Ste. Croix (Matér. Pal. Suisse , ser. 4), pt. 3 
pp. 409, 417, pl. exxix, fig. 9. 
1874. — Derancet, F. G. H. Price. Quart. Journ. Geol. Soc., vol. xxx, 
p. 358, pl. xxv, fig. 7. 
1874. — ovata, Price. bid., p. 357, pl. xxv, fig. 6. 
? 1878. — — OO. Fraas. Aus dem Orient, pt. ii, p. 81. 
1884, = — J.S8. Gardner. Quart. Journ. Geol. Soe., vol. x], p. 125, 
pl. i, figs. 1—3; pl. iv, figs. 28—30. 
1884. _ CAPSEFORMIS, Gardner. Ibid., p. 127, pl. iii, figs. 4, 5. 
Non 1827. Nucuua ovata, 8. Nilsson. Petrif. Suecana, p. 16, pl. v, fig. 5. 
= Als HA): = — od. Phillips. Geol. Yorks., pt. 1, pl. ii, fig. 10, p. 122. 
— 1837; = —  W. Hisinger. Lethea Suecica, p. 59, pl. xviii, fig, 7. 
— 1846. — — A. #. Reuss. Die Verstein. der béhmn. Kreideformat., pt. 2, 
p. 8, pl. xxxiv, fig. 25. 
— 1889. — —  O. Griepenkerl. Die Verstein. der Senon. Kreide von 
Konigslutter (Paleont. -Abhandl., 
vol. iv), p. 56. 
— 1898. — — A. Fritsch. Stud. im Geb. der bohm. Kreideformat. 
v. Priesener Schichten, p. 92, fig. 103. 
— IE — — A. Hennig. Revision af Lamellibr. i Nilsson’s ‘ Petrifacta 
Suecana,’ p. 63, pl. iii, fig. 21. 
Deseription.—Shell oblong or ovate-oblong, short posteriorly, compressed, 
with a slight constriction near the margin opposite the umbo; central part of the 
ventral margin straight and nearly parallel to the dorsal; anterior margin 
rounded, forming an obtuse angle with the dorsal; posterior margin slightly 
angular, but sometimes somewhat rounded. Umbones not much curved. A 
slight depression usually extends from near the umbo to just below the posterior 
angle, giving a slight sinuosity to the margin at that point. Lunule ovate, not 
much depressed, sometimes ill-defined. Surface smooth, but with lines of 
growth ; and in a few cases faint indications of radial ribs, seen chiefly near the 
middle of the valve. Margins smooth. Adductor impressions shallow. 
