336 Dr. FiTTON on the Strata below the Chalk. App. A.] 



Fig. 9. Modiola bella. Neatly striated, convex, with parallel edges, nearly equal sides, and 

 obtuse beaks. 



Fig. 10. Limn semisulcata. {Plagiostoma semisulcatum, Nilsson, Petrif. Suec. 25, t. ix. f. 3.) 

 Ovate elongated, very convex, the beaks incurved, short ; ears nearly equal, small. Where the 

 lines of growth cross the ridges, which vary in number from 11 to 16, they form obtuse, short 

 scales or grains. 



Fig. 11. Auricula injlata. (Benett's Catalogue of Wiltshire Fossils, 4to, p. 2.) Shell ovate; 

 spire small, pointed ; the last whorl large ; aperture at the lower part approaching to square, 

 but with one of the upper angles elongated and acute ; the lips united, thick, obtuse ; the colu- 

 mella has two plaits, the lower sometimes divided by a groove along its middle. The surface of 

 the shell is marked with numerous spiral lines of elongated punctures. The thick lip separates 

 this from several species of Tornatella, to which in other respects it bears a strong resemblance. 

 Auricula incrassala of Min. Conch, t. 163. is shorter and smaller, and has the lip more enlarged. 

 A. incrassata of Mantell (Geol. Sussex, t. xix. f5gs. 2, 3, and 34.) also resembles it, but has a 

 much shorter spire. 



Fig. 12. Natica canaliculata. {Ampullaria canaliculata, Mantell, Geol. Suss. tab. xix. fig. 13.) 

 Globose, depressed, smooth. Umbilicus large, circular, gradually expanded into the base. Around 

 the upper edges of the whorls is a concave, transversely striated groove, best defined in the 

 young shell, — as in c. The inferior specimen, a b. is filled with brownish phosphate of lime. 

 See the figure of a much larger specimen, Plate XVIII. fig. 6. 



Fig. 13. Solarium ornatum. Discoid, with a small portion of the spire elevated and acute; 

 aperture rhomboidal. Surface, above ornamented with obtuse, radiating ribs, — and near the 

 margin, both above and below, with granules in quincunx order. 



Fig. 14. Solarium conoideum. (Min. Conch, t. 11.) A conical shell as high as it is wide ; the 

 umbilicus large and smooth. The outer coat of the shell is i-epresented in this figure ; and shows 

 the upper part of each whorl to be concave, and elegantly marked with decussating striae forming 

 rows of granules; aperture rhomboidal, nearly square. 



Fig. 1.5. Pyrula Stnithii. Ovato-fusiform ; two obscure keels and numerous striae wind 

 round its surface ; spire rather elongated, acute. These two figures, perhaps, represent different 

 species : fig. a. is more distinctly keeled than fig. b., which, however, being considerably worn, 

 has lost much of its external sculpture ; but shows also longitudinal undulations, which can 

 hardly be traced upon fig. a. Both the specimens are from Copt Point, near Folkstone. Murex 

 Smithii (Min. Con. 578), lately removed to the genus Pyrula, is a different shell. 



Fig. 16. Rostellaria elongata. Presumed to be a Rostellaria, from its resemblance to R. mar- 

 ginata, fig. 18. ; from which it differs principally in its great length and the smaller number of 

 ribs. Turrited, much elongated, ribbed, transversely striated ; upper edge of the whorls smooth. 



Fig. 17. Rostellaria buccinoides. A neat, subulate, costated shell, approaching to R. rimosa : 

 it has but one varix upon each whorl : the lip is not lobed. 



Fig. 18. Rostellaria margiiiata. Turrited, conical, transversely striated ; ribs eight or ten upon 

 each whorl, short and obtuse ; last whorl keeled, without ribs. Named from a ridge or narrow 

 band upon the upper edge of each whorl ; which is more or less conspicuous in every specimen, 

 and assists in distinguishing the species from Rostellaria Parkinsoni. See PI. XVIII. fig. 24. 



Fig. 19. Rostellaria carinata. (Mantell; Fossils of the South Downs, p. 86, PI. XIX. figs. 10, 

 11, 12, and 14.) This figure, from a drawing by the Rev. G. E. Smith, exhibits the lip in an ad- 

 vanced stage of growth. The spire is nearly subulate, composed of eight or nine convex whorls; 

 a row of small tubercles, or short ribs, winds round the middle of each whorl except the last, 



