344 Dr. FiTTON on the Strata below the Chalk. [App. A. 



Fig. 18. Fusus rusticus. A short, rugged, ovato-rhomboidal shell; with 10 or 12 ribs, each of 

 which is formed into two knobs, so arranged as to give a squareness to the whorls ; transversely 

 striated ; aperture ovate. 



Fig. 19. Fusus claihratus. Sub-pyriform, costated and transversely striated; four carinas 

 crossing the costas divide the surface of each whorl into three rows of cells ; spire very short. 

 The form is nearly that of a Pyrula. 



Fig. 20. Pyrula depressa, Pyriform, with the spire sunk beneath the surface of the last whorl. 

 Ornamented with many transverse, thread-shaped ridges. 



Fig. 21. Pyrula Brightii. Ovate, sub-rhomboidal, ventricose, transversely bicarinated, and 

 coarsely striated: aperture sub-rhomboidal; whorls four or five. Some specimens resemble F«iU5 

 quadratus, (fig. 17.); but they are shorter, have fewer and more thread-like striae, and crenated 

 carinas. — Named after Richard Bright, Esq. of Ham Green, near Bristol. 



Fig. 22. Rostellaria retusa. A short, ovate, striated shell ; whorls rounded, with one distinct 

 and one obscure carina on each. It has only one elongated, narrow branch to the lip. The 

 surface between the striae is particularly smooth. 



Fig. 23. Rostellaria macrostoma. Turrited, with convex, carinated whorls ; carinae five, the 

 middle one most prominent ; aperture small, round, with a very much expanded and flattened lip, 

 furnished with at least two branches besides the curved beak. 



Fig. 24. Rostellaria Parkinsoni. (Mantell ; Geol. of Sussex, 1. 18. figs. 1, 2, 4, 5, 6, and 10. 

 Min. Con. t. 55S, upper fig. 3.) Turrited, transversely striated, costated ; costae numerous, 

 oblique, long ; aperture narrow ; its broad lip furnished with one large subulate process directed 

 upwards, and a broad angular expansion below it ; beak long and subulate. The specimen, of 

 which two views are here represented, is not perfect, but yet shows the form of the shell better 

 than any before published, and proves that Mr. Parkinson's specimen from Faversham is a dif- 

 ferent species, although figured as the same in the Min. Conchology. 



Fig. 25. Nassa lineata. Ovate, acute, wide at the base, transversely striated ; whorls flattish, 

 the upper edges sharp, distinct ; aperture longer than the spire. Several species from the crag 

 of Suffolk somewhat resemble this ; but in them the body whorl is much smaller. 



Fig. 26. Nassa costellata. Subulate, costated, and transversely striated ; whorls about eight, 

 ventricose, each bearing one varix ; aperture nearly orbicular ; lip thick. 



Fig. 27. Amvionites triserialis. Discoid, with a flat margin, umbilicate, radiated. Three 

 rows of protuberances, upon the marginal portions of the radii, and about ten tubercles around 

 the umbilicus, distinguish this species. The aperture is nearly square. All its parts are elegantly 

 rounded, 



PLATE XXL* 



Fig. 1. Cypris Valdensis. {C.Faba'i, Min. Conch, t. 485. — See the observations on the specific 

 names; supra, p. 177.) Oblong-ovate, convex, punctated ; front slightly concave ; at one ex- 

 tremity of each valve is a small oval lobe ; back hollow between the valves. It is very doubtful 

 whether this be the Cypris Faba of Desmarestf , which is the inhabitant of a much newer fresh- 

 water formation than the Wealden, and appears from the figure to be of a somewhat different form. 

 When the figure in the Min. Conch, above referred to, was published, the author was not aware 

 of there being more than one fossil species of Cypris, and supposed that the minute differences 



* Plates XIX. and XX, containing representations of Endogenites erosa, are described above, 

 p. 172 — 176. : see also hereafter, p. 349. 



t Bull, de la Soc. Philom. 1813, p. 259. PI. IV. No. 8. ; Hist. Nat. des Crustaces Foss.p. 141. 

 PI. XL fig. 8. 



