752 ME. F. E. G. EEED ON THE LOWEE PALiEOZOIC [NoV. 1 899, 



The occipital ring is marked off by a strong neck- furrow, is 

 rounded, and wider in the centre than at the sides. 



The fixed cheeks are wide, gently convex, with the genal angles 

 rounded. A strong neck-furrow marks off the neck-ring, which 

 broadens gradually towards the genal angle. 



The eye is situated at about one-third of the width of the glabella 

 from the axial furrow, and opposite the second glabellar furrow. The 

 eye-ridge runs out from the level of the first glabellar furrow to the 

 eye. 



The posterior branch of the facial suture runs almost parallel to 

 the posterior edge of the head-shield ; the anterior branch curves 

 inward and forward to the front border. 



The ornamentation is important. It consists of scattered tu- 

 bercles of two or three sizes, but none are very small. They are 

 distributed all over the glabella, cheeks, and neck-ring, and, except 

 on the glabella, have no definite arrangement. On the glabella 

 those of the first size seem to have a regular plan of arrangement. 

 On the frontal lobe there are two median parallel pairs of large 

 tubercles, placed so as to form a square, with also two smaller 

 tubercles closer together in front. Inside the square is a diamond 

 pattern, formed by four small tubercles. 



Behind these, on the central portion of the glabella, are six large 

 tubercles roughly arranged in three rows. 



Measurements. 



mm. 



Length of head-shield 7*0 



Width of the same 14-0 



Length of glabella 50 



Width of the same 4*0 



This species is allied to C. verrucosa^ Dalm. but differs from it 

 in the shape and characters of the glabella and lateral lobes. In 

 these points it resembles G. rex^ ^ieszk. but differs in the tuber- 

 cular non-punctate cheeks and absence of frontal marginal spines. 



The form of the glabella, fixed cheeks, position of eyes, and 

 tubercular ornamentation ally it to 0. Worthi, Eichw. and 

 0. affinis^ Schmidt, but it differs in the lobation and furrows of 

 the glabella. Though the ornamentation reminds one of O. hella- 

 tula, Dalm. yet the position of the eyes and glabellar characters 

 are completely different. 



In these beds of Newtown Head 0. rugosa, Portl. occurs, and it 

 may be that 0. McHenryi is merely the head-shield of this species. 

 But until the pygidium of the one is definitely found in connexion 

 with the head-shield of the other, it seems to me safer to keep them 

 distinct. 



Cybele sex-tijberculata, sp. nov. (PL XLIX, fig. 8.) 



A slightly distorted head- shield of a new species of Cyhele 

 (No. 1412) which is in the Geological Survey Collection at Dublin 

 comes apparently from Stage 2 of the Tramore Limestone Series of 



