Vol. 55.] "BEDDED KOCKS OF COTJJ^TY WATERPOBD. 757 



portions. The oblique striation which Salter figures does not 

 extend so far inward from the margin, but reaches only to the tip 

 of the axis, and maintains the same width all round the sides. 

 A specimen in my collection is from Stage 3, JN'ewtown Cove. 

 A. racliatus has been found in County Louth, as well as at Rhiwlas ; 

 Salter (op. cit.) compares it with a Eussian Ptychopyge described 

 by Lawrow. 



AsAPHUS (Ptychopyge) sp. 



A distorted and imperfectly-preserved pygidium from Stage 1 of 

 the Tramore Limestones of Dunabrattin is of a broad semicircular 

 shape, with seven or eight ribs on the pleural portions, a conical axis 

 of the same shape and relative length and distinctness as A. rectifrons, 

 measuring about one quarter the width of the pygidium at its front 

 end, and extending for about two-thirds of its length, with seven or 

 eight rings indicated on it. 



This form may be compared with Angelin's Ptycliopyge lata} 



AsAPHUs Haughto^^i, sp. nov. (PL XLIX, fig. 13.) 



An exceedingly well-preserved specimen of a pygidium from the 

 Tramore Limestone Series (Stage 2) of Tramore, in the Geological 

 Survey Collection at Dublin, shows certain peculiar features which 

 render it necessary to create a new specific name. Its characters 

 are as follows : — 



Outline broadly parabolic, gently convex from side to side, 

 flattened from front to back, furnished with a rather broad concave 

 depressed border. Surface smooth, unornamented. Anterior 

 margin nearly straight, lateral angles not truncated. Axis marked 

 only by a very slight curving forward of the margin, and by a weak 

 depression on each side. A sharp raised ridge on each side of the 

 axis runs from this depression obliquely outward and backward 

 to the lateral border at an angle of about 15° to the front margin, 

 limiting posteriorly the elongated triangular surface of the articula- 

 tion at the lateral angle. This triangular facet is marked by a few 

 faint irregular raised lines. The ridge becomes suddenly very weak 

 on crossing the concave border, and is defined posteriorly by a deep 

 furrow which ends at this border. 



At the posterior end of the pygidium the border is rather nar- 

 rower than at the sides, and has a width of about one-fifth of the 

 total length of the pygidium. It is everywhere markedly excavated 

 and depressed below the central elevated, gently convex portion of 

 the pygidium. A slight truncation and bending-up of the edge is 

 noticeable directly behind the posterior end of the axis. Axis less 

 than one-third the width of the pygidium, very depressed, only 

 indicated near the anterior margin by a very faint independent con- 

 vexity ; behind this it is entirely indistinguishable, being level with 

 the general surface and without axial or transverse furrows. Its- 

 posterior end, however, is indicated in front of the concave bordery 



1 ' Pal. Scand.' 1854, p. 55 & pi. xxxi, fig. 1. 



