Vol. 55.] BEDDED ROCKS OF COUNT T WATEEFORD. 755 



is convex and prominent ; each ring has a median raised rounded 

 ridge, ornamented with tubercles and furnished with a narrow flat 

 articulating band on the anterior and posterior margins. A con- 

 spicuous nodule is seen on each side, as in Calymene Blumenbachi. 

 The pleural portions are gently convex, for the pleurae curve down- 

 ward beyond the obscure fulcrum. Each pleura is nearly straight 

 to a point a little beyond the fulcrum, but then it bends backward 

 somewhat. The fulcrum is situated at a distance of about two-thirds 

 the length of the pleura from the axial furrow. The surface of 

 each pleura bears a median rounded tuberculated ridge, like the axis, 

 with a narrow anterior and posterior articulating band extending 

 out as far as the fulcrum. The free ends are bluntly pointed. 



The pygidium resembles in shape that of E. sexcostatus, but it 

 has only twelve to fifteen rings marked on the axis, and of these, 

 usually the first nine or ten (but sometimes only the first four) 

 are continuous across the axis as complete rings. The axis ends 

 a short distance from the posterior end of the pygidium, tapering 

 gradually backward to its bluntly-pointed extremity. 



There are five strong rounded pleurae on each side, rather more 

 strongly curved back than in E. seoccostatus. The sixth pleura is 

 very short, closely pressed against the side of the axis, and often 

 obscure. The first four pairs are large, distinct and prominent, 

 possess no furrows, and curve regularly backward. The fifth pair 

 is weaker, and runs nearly straight backward. The sixth pair, as 

 stated, is very weak and short. 



There are several large tubercles on each axial ring of the 

 pygidium, with smaller tubercles irregularly scattered between them. 

 On the first pleura there are three or four large equidistant tubercles ;. 

 on the second two or three ; on the third two ; and on the fourth 

 and fifth one or two. Salter (op. cit.) says that in E. secccostatus 

 the ribs are always smooth. 



Measurements. 



(1) (2) (3) 



mm. mm. mm. 



Length of head-shield 4-5 5-0 7*0 



Width of the same 10-0 100 13-0 



Length of pygidium 65 50 7'0 



Width of the same 9-0 9*0 8-5 



Affinities. — Though this species is allied to E. sexcostatus by 

 many characters, yet it shows several differences of some importance :: 

 (1) its glabella is not swollen in front, and does not overhang the 

 front margin ; (2) the lateral furrows of the glabella are difi'erent ; 

 (3) the cheeks are tuberculated, not pitted ; (4) the number of 

 axial rings in the pygidium is less ; (5) the pygidial pleurae curve 

 back more strongly and are ornamented with tubercles ; (6) the 

 sixth pair of pleurae is nearly obsolete. 



Megalaspis, sp. a. 



A small hypostome, 9 mm. long, in the Geological Survey Col- 

 lection at Dublin, shows by its characters that it belongs to this 



