552 



PROCEEDINGS OP THE GEOLOGICAL SOCIETY. 



portion of the shell occupies only about one-half the dimensions of 

 its dorsal surface. 



Locality, The Liassic coralliferous conglomerate of Brocastle. 



53. DlSCOHELIX PIMBEIATT7S, SpOC. UOV. PL XVI. figS. 4, 5. 



^ Shell discoidal, depressed ; whorls 5-6, on the same plane, or but 

 slightly raised, moderately convex. Surface of the shell covered by 

 very close, regular, encircling striae, which cross irregular, flattened 

 costae, or lines of growth, giving a wavy appearance to its ornamen- 

 tation. The costae terminate on the inner margin of the whorl in 

 very depressed nodules, and on its outer margin in an elevated 

 nodulated carina, which extends far beyond the chambered portion 

 of the shell — the carina sometimes occupying about a third of the 

 diameter of the shell. The back is angulated and retreating towards 

 the umbilicus, and is covered, like the upper surface, with regular 

 striae, but which are waved as they approach the carina. Umbilicus 

 deep, very large ; aperture not exposed. 



Of this very pretty and remarkable shell I possess but one ex- 

 ample shovmig the upper surface and the back, and a second giving 

 a section of the chamber. 



They are from the Erocastle conglomerate. 



54. SoLAErtTM LTJi^ATTiM, spcc. nov. PI. XYII. fig. 15. • 



Shell small, discoidal; whorls four, the upper convex, rounded, 

 and slightly raised ; surface ornamented by regular curved lines, 

 which are bounded on the side of the body-whorl by a sinus, which 

 becomes obsolete in its younger condition ; beneath the sinus is an 

 acute encircling carina ; underside not exposed. 



Of this pretty shell there are two examples attached to the block 

 extracted from the Liassic vein at Holwell. 



5b. Teochotoma Beocastellensis, spec. nov. PI. XY. fig. 29. 



Shell turbinated, concave ; apex obtuse ; whorls five, having on 

 their surfaces depressed transverse striae; base of the whorls 

 bounded by an encircling rib, on which are three close-set striae, 

 immediately beneath which is a slight sinus. The whorls are an- 

 gulated (the upper portion of the body-whorl most so), and are 

 ornamented by curved or oblique, depressed costae. 



This species is rare, as I possess only one other imperfect ex- 

 amjple. The base of the shell is surrounded by the matrix. 



It is from the Liassic conglomerate of Brocastle, and the largest 

 species yet obtained from that locality. 



bQ. Teochotoma Lycettii, spec. nov. PI. XY. figs. 27, 28. 



Shell discoidal, depressed ; spire flattened ; apex rather acute ; 

 whorls five, with numerous encircling striae, those in the centre and 

 at the base of each volution being most elevated ; the upper margin 

 of the whorls flattened or angular, with irregular curved or almost 

 obsolete lines of growth. The basal margin of the shell is sur- 

 rounded by a raised rim composed of three or four slightly nodulated 



