LOCALITIES IN "SILURIA." 103 



Pteraspis with scales attached, an account of which was communicated by him to the 

 Geological Society in March, 1864 (see Quart. Journ. Geol. Soc, vol. xx, p. 194, &c). 



The quarry West of the road, and opposite the Old Farm House near the East quarry, 

 is lower in the series by a few feet than the other, and the flags and Cornstones therein are 

 full of remains of Pteraspis, Cep/ialaspis, and here and there traces of Crustacean chelae 

 and portions of carapaces. Specimens of these remains may be seen at the Museum at 

 Worcester, and at the College at Malvern, also in Dr. Grindrod's collection at Townshend 

 House, Malvern. 



It is almost impossible to distinguish these beds, as far as carbonaceous markings and 

 mineral aspect goes, from similar beds at Rowlestone, and Cusop, Hay, which are higher 

 in the series of the Old Red Rocks. 



13. — Old Red Sandstone (Lower Cornstones), Pontrilas, and Monmouth Cap, 



Herefordshire. 



The Cornstone beds of the Old Red Sandstone commence nearly at the base of that 

 formation, as seen near the railway-cutting at Wall Hills near Ledbury, where their 

 position, as regards the Passage-rocks and Upper Silurians, may be studied. But even 

 here there is a fault across the Passage-beds on the line of the River Leddon, and we 

 have the consequent denudation and obscurity. Ascending upwards we find higher 

 Cornstone groups, interbedded with marls, sandstones, and flagstones. 



With no Silurian base to give us a starting point within many miles, we have 

 only fossils to guide us as to the position of the strata exhibited near the Station at 

 Pontrilas on the Hereford and Abergavenny Railway. Years ago, when the railway arch 

 was building at Pontrilas, I saw a portion of a Pish, either Pteraspis or Cep/ialaspis, built 

 into the wall ; and afterwards my friend Mr. Thackwell and myself obtained fragments and 

 plates of these Pishes and portions of the carapaces of Crustaceans from the loose debris 

 in the quarry. Plant remains occur here ; and it was from the equivalent beds near 

 Ewyas Harold Castle, I believe, that Dr. McCullough and Mr. Salter obtained the 

 remains of a gigantic Pterygotus} 



The sections here are difficult to follow out, owing to the lanes, &c, being so much 

 obscured; but a walk from the quarry at Pontrilas Station by the Common of Ewyas 

 Harold will lead the geologist to a Cornstone quarry yielding remains of Cephalaspis and 

 Pteraspis. When the position of this quarry is compared with that of others on the 

 opposite side of the River Munnow, above Monmouth Cap, and near Grosmont, the 

 geologist will have little doubt that these Cornstone beds overlie the Pterygotus- and 

 plant-bearing rocks of the Pontrilas Station. 



1 Pterygotus taurinus, Salter, see pp. 75 and 76 of this Monograph. — H. W. 



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