CARBONIFEROUS FOSSILS OF IRELAND. 37 



EUOMPHALUS PENTANGULATUS. SoW. 



Euoniplialus pentangulatus. Sow. Min. Con. — Euomplialus pentangulatus. Phil. Geol. York. — Euomplialus Bronnii. 



Portk. Geol. Eep. 



Sj>. C7( .-^Spirc flat above ; wliorls convex, very obtusely carinatecl beneath; back very convex; upper 

 portion of each whorl divided near the centre by a distinct, but not sharjJ, keel ; that portion of the surface on 

 the outside of the keel is convex, that on the inside flat. 



Tliis very common shell has about five turns in the spire ; the umbilicus is very wide, but shallow, the 

 spire being very slightly raised ; the under portion of the whorls is very convex, and obtusely angulated in the 

 middle ; the back is slightly compressed ; diameter two inches, height of spire nine Unes, thickness of the last 

 whorl eiidit lines. 



o 



EuOMPHALUS PILEOPSIDEUS. Fhil. ST. 



Cirrus pileopsideus. Pf/il. Geol. York. 



Sp. Ch. — Discoid, depressed; spire scarcely elevated above the level of the basal whorl, composed of four 

 obtusely rounded, slightly imbricating whorls, rather coarsely striated across. 



A few imperfect specimens have occurred of this species. Diameter seven lines, thickness of last volution 

 three Hnes. 



EuOMPHALUS QUADRATUS. MCoy. (PI. V. fig. 22). 



Sp. Ch. — Discoid; spire flat, of three or four whorls; umbilicus very large, rounded; whorls square, finely 

 striated across. 



This Httle species is remarkable for the square form of its volutions ; the spire is perfectly flat, as if trun- 

 cated; the back broad, and bounded by two distinct keels, between which it is flat, or very slightly convex. 

 Diameter six Hnes, length of mouth two lines, height of mouth two lines. 



EuOMPHALUS EOTUNDATUS. SoiV. SP. 



Helicites Dionysii. Sc/ilot. — Euomplialus Dionysii. Gold, and Bronn. — Cirrus rotundatus. Sok. Min. Con. — 



Cirrus rotundatus. Pliil. Geol. York. 



Sp. Ch. — Obtusely conical; volutions five or six, rounded, tip obtuse; height of the spire rather more than 

 two-thirds the diameter of last whorl; surface with faint, direct lines of growth. 



This species is distinguished from the E. acutus by the volutions being uniformly convex, without the 

 flattened space on the upper part of each whorl, which is found in that species ; the volutions are about five in 

 number. Diameter one inch six lines, height of the spire one inch. 



EuOMPHALUS SERPENS. Pllil. 

 Euomphalus serpens. Phil. Pal. Fos. 



Sp. Ch. — Discoid, spire convex, of four rounded, smooth whorls; umbilicus very wide, extending to the 

 tip of the spire. 



The Irish specimens are referrible to the smaller variety of this species found in N. Devon, and figured by 

 Professor PhiUips in PI. XXXVI. fig. 172, c. d. e. Diameter six lines, height of spire two and a half lines. 



K 



