MOOKE — abxoe:>ial secondary deposits. 547 



striae. At the base of the whorls is a transverse, rather elevated, 

 smooth rib. Aperture longer than wide, ovate ; columella with slight 

 fold ; canal short. 



This pretty little species is not uncommon, though rarely found 

 perfect. It is from the Liassic conglomerate of Brocastle. 



35. Nerin^a HoRNERi, spec. nov. PL XYII. hg. 12. 



Shell conical, composed of six convex, rapidly increasing whorls ; 

 spire rather depressed ; apertui^e rhomboidal ; columella thick, with 

 two folds upon its inner margin ; no umbilicus. 



The surface of the volutions is ornamented Avith numerous en- 

 circling nodulated costae, which continue to the base of the shell in 

 the interspaces, between which are numerous perpendicular striae. 



This pretty shell in its general contour is more depressed than is 

 usual with Nerincea. Several specimens of it are attached to the 

 fossiliferous Liassic block extracted from the vein at the base of the 

 Carboniferous Limestone quarry at Holwell, the matrix in which 

 represents in this country the horizon of the Hierlatz beds. 



36. Neeii^^a Mendipexsis, spec. nov. 



Shell small, cylindrical ; upper part of the whorls flattened, rather 

 convex towards their base. 



This shell is not perfect, and is otherwise in bad condition, but 

 it is sufficiently distinct to be separated from iV^. acmnhmta of 

 Brocastle. As this is the only specimen of the genus which I pos- 

 sess from the Charter-House lead-mine, I notice it chiefly to record 

 its presence at that place. 



37. Nerix^a rtjdis, spec. nov. PI. XIY. fig. 23. 



Shell turreted, cylindrical; whorls flattened, with a small but 

 well-marked suture and with encircling but faint striae, which are 

 continued on the base ; apertui'e large and longitudinally ovate ; 

 columella mth a short canal. 



I possess two examples of this shell, neither of which has the 

 test well preserved, and the apex of one is concealed whilst the 

 other is imperfect. 



They are from the coralliferous conglomerate of Brocastle, and 

 are, with a little hesitation, referred to this genus. 



38. Neritopsis l^vis, Stol. PI. XYII. figs. 3, 4. 



Shell small, depressed; whorls convex, rapidly increasing, and 

 ornamented with very fine encircling striae ; aperture quite circular, 

 and large in proportion to the shell ; outer lip thin, but thickening 

 towards the base. One example of this shell is in my possession, 

 attached to the block from the Liassic vein in the Carboniferous Lime- 

 stone at Holwell. It is stated by Dr. Stoliczka to be rare in the 

 Hierlatz. 



39. Neritopsis exigua, Torq, PI. XY. fig. 19. 



Shell moderately large, thick, neritiform, ovately globose : spire 



'2p2 



