MOORE ABNORMAL SECONDARY DEPOSITS. 543 



1 possess but one example of this shell, which wants one or two of 

 the upper chambers. 



Loc. The coralliferous Liassic conglomerate of Brocastle. 



19. Cerithium nodulosum, spec. nov. PI. XIY. fig. 9. 



Shell very large ; spire tnrrcted and much elongated, convex, 

 angnlated ; whorls spirally coiled, elongated ; the upper portions 

 regularly angulated towards a Avell-marked concave suture. Towards 

 the base of the volutions there occurs a single row of very prominent 

 and rather widely separated nodulations ; aperture longitudinally 

 ovate. 



Of this fine species I possess only one example showing the test; 

 but this is lost on the lower whorl, and several of the upper ones are 

 wanting. My specimen consists of five whorls, which measure 4 

 inches in length ; and it is probable the shell must have been about 

 5 inches long when perfect. 



It is from the Lias with Ammonites Bucldandi and A. cmgulatus at 

 Shepton Mallet, and is represented, at Southerndown, Sutton, and 

 Dunraven, by the large sections of its shells, which are there seen on 

 the siu"faces of the beds. 



The outer chamber of my specimen contains a Discina Davidsoni, 

 Moore. 



20. Cerithitjm spirattjm, Moore. PL XIY. fig. 12. 



Shell spiral, narrow and very elongate ; apex acute ; possessing 

 14-15 very slowly increasing volutions, which are divided by a 

 small angulated encircling suture ; the surface of the whorls orna- 

 mented by close spiral striae, which arc crossed by six or seven 

 raised oblique longitudinal costae. Aperture rather ovate. 



This pretty species does not appear to attain any considerable 

 size, and, though it is not uncommon, it is rarely found quite perfect, 



Loccditij. The coralliferous conglomerate of Brocastle. 



21. Chiton radiatijm, spec. nov. PI. XYI. figs. 25, 26. 



Shell elliptical or transversely oval, flattened ; dorsal surface con- 

 vex, smooth, possessing a central, broadly grooved, slightly raised 

 apex, with lateral depressed areas ; anterior convex, divided into 

 two areas by a curved or folding line, the surface presenting radi- 

 ations passing from beneath the umbo. 



I possess four examples of this shell, only one of which is in 

 good condition. I have previously found this genus in the Middle 

 and Upper Lias, and also in the Phactic beds, this being the first 

 instance in which it has been recognized in the Lower Lias. Al- 

 though comparatively rare, the genus has now been found in every 

 geological stage down to. the Lower Silurian. The same species also 

 occurs in the Liassic lead-mine of Charter House and the Lower Lias 

 of Bedminster, the figured specimen being from the coralliferous con- 

 glomerate of Brocastle. 



22. DELrniNULA NrDA, spec. nov. PI. XYII. fig. 10. 



Shell turbinated; spire elevated; volutions five, oblique, much 



