Fearnsides, Elles, Smith — Pakeozoic Rocks of Pomeroy. 123 



two basal lobes. A single glabella furrow connects the two. At the 

 summit of the glabella there is a tubercle. I^eck furrow clearly 

 defined. 



Cheeks. — Triangular and covered with pits, arranged in anasto- 

 mosing grooves. 

 Eyes. — Absent. 



This species is represented in our collection by an almost perfect 

 head. 



Horizon and Locality. — Killey Bridge beds (?). Little Eiver, 

 Tirnaskea. 



^glina rediviva Barr. 

 Sead-shield. — Circular, with rounded genal angles. 

 Glahella. — Smooth, and but faintly defined by two shallow axal 

 furrows at the posterior margin. 



Cheeks, — Lateral margins flattened where eyes attached. 

 Eyes. — Not preserved. 



Thorax. — Axis occupying more than one-third the entire breadth 

 of the body ; segments five in number ; pleura grooved and rounded 

 at extremities. 



Pygidium. — Semicircular ; slightly inflated ; about as large as head 

 (excluding eyes). 



Axis short, truncated, with one or two furrows ; tail-segments 

 faintly indicated by two shallow grooves ; margin flat. 



This Trilobite is represented in our collection by narrow scattered 

 head-shields and pygidia, with or without thoracic segments. One 

 complete specimen was found 4*5 mm. in length, but some of the 

 larger specimens must have measured fully 10 mm. when perfect. 



In some of the specimens the axis of the tail appeared to be 

 somewhat larger than in others, and to be more tapering. This may 

 be due to age. 



Sori%on and locality. — Upper Tirnaskea beds. Tirnaskea. 



Of the other Trilobites collected from Pomeroy upon this occasion 

 little need be said ; they have mostly been described by Portlock in his 

 Londonderry Report. 



Remopleurides Colhii and R. dorsispinifer were both identified ; 

 cephalic shields and pygidia oiPhacops{Dalmanites) mucronatus (Brong.) 

 were abundant in the Tirnaskea beds. 



Phacops truncato-caudatus (Portl.) was represented by portions of 

 head and pygidium, and seems to differ slightly from Portlock' s desciip- 

 tion in having a slightly narrower glabella. Our specimens agree in 

 every respect with those previously collected from Pomeroy, now 

 preserved in the Sedgwick Museum, Cambridge. 



