Page:VCH Herefordshire 1.djvu/57

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GEOLOGY Phillips made two divisions of the May Hill Beds — a lower, in which conglomerates and thick-bedded sandstones predominate ; and an upper, in which shale-beds are more in evidence. The conglomerates at Howler s Heath contain rolled fragments of Malvernian rocks, and the upper beds have yielded specimens of Stricklandinia and Pentamerus. The upper beds have been observed at Wain Street, Stump's Wood, and below the Obelisk in Eastnor Park, where at certain horizons they are very fossiliferous, and it was here that the oldest known Pterygotus was found." North of the ObeUsk the outcrop of the May Hill Beds is not very distinct ; but they have been noticed at several places, and it was near the Wyche that Miss Phillips found the peculiar conglomerate containing May Hill Sandstone fossils that bears her name.'^ In the Cradley district — although the beds are very much disturbed — the sequence of the upper strata is more complete than farther south. Near Cowleigh Park small patches of Archaean rocks occur, intro- duced by faulting and folding into the main mass of the Llandovery Beds. The Woolhope Limestone is well-developed in the Malvern country and usually forms the steep slope down to the little valleys excavated in the over- lying Wenlock Shales. Usually it is inclined in a westerly direction, but near Walm's Well it dips eastwards. This is because the rock exposed is a remnant of the eastern limb of one of those over-folds such as we have said were produced in the crust-crumpling that took place in late Carboni- ferous times. On the west side of the Cradley district the limestone crops out along a fairly regular line, but on the east it occurs only in two small outliers, in one of which it has been worked. The Woolhope Limestone is a useful road-metal, and has been quarried at Gold Hill and Stump's Wood in the Eastnor area. The Wenlock Shales, being soft, are worn into valleys overlooked by well- defined ridges of Wenlock Limestone. The Glynch Brook, from its source at Walm's Well to the confines of the Silurian area at Clincher's Mill, follows the outcrop of these Shales, and the ornamental sheet of water at Eastnor Castle lies in a hollow excavated out of them. Being a shale- formation the beds are of little or no commercial value, and therefore rarely exposed except in lane-sides and natural sections. There is a section at Linden, however, where a number of fossils have been found." The Wenlock Limestone is represented either by several massive beds of limestone, or by one bed with deposits of nodules, embedded in shale, above and below. Commercially, the limestone is of much importance, and therefore there are many quarries. In the large one on the hill above the tunnel at Ledbury, two thin beds — together measuring only 1 8 in. — have furnished limestone that takes a high polish and has in consequence been locally employed as an ornamental stone, and designated ' Ledbury Marble.' Fossils are abundant throughout the subdivision, and there are few amongst the numerous quarries that have been opened near Ledbury, Netherton, in Colwall Copse, and in the Cradley district, whose strata do not abound in corals and brachiopods. When the railway between Ledbury and Malvern See Symonds in Woodward's Monogr. Brit. Fossil Crustacea, Ord;r Merostomata (Pal. Soc), p. 92. '^ T. T. Groom, Quart. Joum. Geol. Soc. Iv (1899), pp. 139, 143-5, 153. ^' Mem. Geol. Surf, ii, pt. i (1848), pp. 156-63. *" Quart. Joum. Geol. Soc. Ivi (1900), pp. 147-8. 13