PALEOZOIC MOLLUSCA. 24f> 



of each is slightly concave, becoming very convex in the lower 

 half; band narrow, below the middle on the most convex part 

 of the volutions; striae sharp, strongest on the thickened 

 edge of the suture, arching obliquely backwards to the band. 

 Length 6 lines, proportional length of last turn -^^j^, width 



50 



Too* 



As neither the collar-like thickening of the upper edge of the 

 suture, nor the greater projection of the lower part of each whorl, 

 are indicated by Mr. Sowerby in his figure or description (in the 

 Sil. Syst.) of the P. Corallii, I suppose the present species to be 

 distinct. 



Common in the Upper Ludlow of Spital and Benson Knot, 

 Kendal, Westmoreland; tilestone of Storm Hill, Llandeilo, Caer- 

 marthenshire. 



(Col. University of Cambridge.) 



Euomphalus lyratus (M'Coy). 



Desc. Spire only slightly elevated, of two very convex turns, each 

 with three narrow spiral ridges, one at the upper suture, one 

 considerably above the middle of the body-whorl and corre- 

 sponding to the lower suture on the spire, and the third half- 

 way between these two ; surface crossed by slightly oblique, 

 thin, cord-like ridges, nearly twice their thickness apart. 

 Diameter about 6 lines, proportional height about -{-^-q. 



Only one imperfect specimen has occurred of this obviously 

 distinct species, not allowing of the characters of the base or 

 spire being completely ascertained. 



Rare in the Bala schists at Llansaintfraid, Glyii Ceiriog, Den- 

 biorhshire. 



'O 



Euomphalus triporcatus (M^Coy). 



Desc. Obtusely conic; apical angle about 95°; spire of about 

 three or four flattened whorls, each bearing three nearly equal 

 and equidistant, thick, obtuse carinse, one of which is at the 

 suture, which it renders canaliculate, one in the middle, and 

 one forming the circumference of the basal whorl, and par- 

 tially concealed by the suture in the spiral whorls ; base con- 

 vex, with three smaller spiral carinas and a minute umbilicus ; 

 surface crossed by sharp, scaly, delicate, transverse striae. 

 Width 1 inch, proportional length about -^q^^, length of last 

 whorl t\%- 



Col. Portlock has, I think, figured this species (Geol. Rep. 

 t. 30. fig. 3) as the E. subsulcatus of Hisinger, which has double 



