176 CARBONIFEROUS CEPHALOPODA OF IRELAND. 



concentric lines of growth, which form a deep and wide hyponomic sinus upon 

 the periphery. 



The name of this species does not occur in Sir R. Griffith's list of localities 

 appended to M'Coy's ' Synopsis ' (1862), but the tablet is inscribed " Co. Limerick 

 --Presented by Sir R. Griffith, Bart." 



Locality. — County of Limerick (exact locality unknown). 



Glyphioceras (Beyeichoceeas) coupulentum, 0. C. Crick. Plate XL VII, figs. 1 a, b ; 



Plate XLVIII, figs. 1 a—c. 



1899. Gtlyphiocekas corpulentum, G. C. Crick. Aim. Mag. Nat. Hist., ser. 7, 



vol. iii, p. 447, fig. 12. 



Description. — Shell much inflated, the greatest thickness at the umbilical margin, 

 about three-fifths of the diameter of the shell ; the height of the outer whorl nearly 

 one-half of the same. Whorls few, their number not determinable from the specimens 

 available ; inclusion nearly complete owing to the greatly expanded sides of the 

 shell ; umbilicus deep, with subangular margin and precipitous sides ; about three- 

 tenths of the diameter of the shell in width. Whorl sublimate in cross-section ; the 

 height about three-fourths of the width ; indented to nearly one-half of its height 

 by the preceding whorl. Periphery broadly convex, imperfectly defined ; merging 

 in the inflated sides. Umbilical zone distinctly defined, narrow, nearly perpendi- 

 cular to the plane of symmetry of the shell. 



Body-chamber occupying nearly the whole of the last whorl; aperture not pre- 

 served, but the lines of growth indicate the presence of a slight crest near the edge 

 of the umbilicus, and a very wide and shallow hyponomic sinus. Chambers shallow; 

 suture-line as in PI. XLVIII, fig. 1 c. 



Test ornamented with fine, subregular, raised lines, which become more distinct 

 in the adult shell ; these extend obliquely and abruptly backwards from the umbili- 

 cal margin and form a very wide and shallow sinus upon the periphery. The latter 

 bears some widely spaced, faintly defined longitudinal bands in the adult; in the 

 young shell these bands extend to the sides of the shell ; though not a very con- 

 spicuous feature, these longitudinal bands give a certain distinguishing character to 

 the ornamentation of the shell when viewed in connection with the transverse lines, 

 and as they persist throughout the growth of the shell they are of definite value as 

 specific data. 1 The cast in the adult individual shows near the aperture two wide 

 and shallow hut quite conspicuous constrictions, and there are indications of similar 

 features in tin' young shell. 



1 The lithographer has omitted the longitudinal hands in the figures of the young shell (PI. 

 KLVIII, figs. la,b). 



