LUDLOW ROCKS NEAR USK. 



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All the organic remains, however, agree with those in the cliffs of the Teme at Ludlow, there 

 being scarcely one characteristic Salopian specimen which is not to be found here. As this and 

 some promontories on the other bank of the Usk are the most southern points in England, at 

 which the Ludlow Rocks are well developed, it is highly important to observe their uniformity 

 of structure, and also that the uppermost strata here pass with equal conformability into the Old 

 Red Sandstone, as in Shropshire and Herefordshire, &c. The extreme northern point of this upper 

 rock is at Clytha Pitch, where it is cut through by the high road from Monmouth to Abergavenny, 

 and where the strata, dipping 10° or 12° to the south-west, are charged with many casts of 

 fossils. There is not here the same clear junction with the Old Red Sandstone as at Usk Castle, 

 the lower slopes of the hills being covered with gravel. Any transverse section of these hills, a mile 

 or more to the south of Clytha Pitch, affords, however, clear evidences of the overlying succession. 

 Thus, in proceeding from Ragland directly across the ridge to Trostrey Lodge, flaglike strata of 

 Old Red Sandstone rise up at Rhiwlais and Tylochor, and dip from the underlying mass of the hill, 

 which at Bettws is a yellowish thin-bedded sandstone, the equivalent of the Downton Castle free- 

 stone, p. 197. These beds are there distinctly underlaid by dull grey Ludlow Rock, in which many 

 of the best known fossils abound, including numerous Orthoceratites. (See PI. 36. f. 23.) 



The chief interest in this group, is in the hilly tract upon the right bank of the Usk. Com- 

 mencing with the ridge and church of Llanbadock, we trace with perfect precision the outline of 

 the grey land, in marked contradistinction to the surrounding envelope of Old Red Sandstone, the 

 Ludlow Rocks rising along the line of separation into a distinct chain of hills, of heights varying 

 from 300 to 500 feet. At Llanbadock, the Upper Ludlow Rocks are arched, and plunge south- 

 eastwards into a plain of Old Red Sandstone at angles of 60°; some of the lower strata which are 

 strong bedded and calcareous, and of an indigo colour, clearly occupying the place of the Aymestry 

 Limestone. The upper beds are full of the Serpuloides longissima, Cypricardia amygdalina, 

 and other fossils. At Llangibby, the modern mansion stands upon the Old Red Sandstone, but 

 the Ludlow Rocks ascend from beneath it into picturesque and wooded hills. The Darran, a rugged 

 crag on the S.W., exposes many of the shelly beds, in some parts highly calcareous. Passing by 

 Slovad's Wood, the same rocks expand over Maesmawr, and are completely developed in the Panta 

 dingle, where the beds conforming to the qua- qua- vers al dip of the central mass, are inclined to 

 the west at an angle of 10°. This is perhaps the best point within the area of the Silurian group, 

 where a clear succession is exhibited of all the strata, from the older formations which occupy the 

 centre of the ellipse in Glasgoed and Prescoed Commons, to the Old Red Sandstone, and even to the 

 carboniferous strata. Being within two miles of the edge of the great coal basin of South Wales, we 

 may thus examine, within a distance of five or six miles, the representatives of all the strata between 

 the productive coal and the Caradoc Sandstone. (See Section, PI. 36, f. 23.) The Ludlow Rock, in 

 this little gorge, is slightly calcareous and traversed by veins of pink calcareous spar, and in one 

 part its beds are separated by a band of pure white, unctuous clay, like the "W T alker's soap" of 

 Salop and Hereford. (See p. 204.) 



Fossils abound, including Terebratula Wilsoni, and some corals, while the beds beneath the 

 hard stone are loaded with the Asaphus caudatus, Productus depressus, &c. The overlying strata, 

 mounting into the hills above Llanfihangel, dip 20° west ; and some of the highest beds, like those 

 of Downton Castle, pass into the Old Red Sandstone, being yellowish, thinly laminated sandstones, 

 and containing, together with the Leptcena lata and other Salopian fossils, the small orthoceratite 

 of the junction beds in the Cwm Dwr, Caermaerthenshire. (See p. 181, & PI. 34. f. 1.) The Lower 

 Ludlow Rocks, on the right bank of the Usk, appear in great thickness in the escarpment of the 



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