Page:VCH Worcestershire 1.djvu/38

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A HISTORY OF WORCESTERSHIRE oblongus, Stricklandinia lens, Orthis calligramma, Atrypa reticularis, Lingula parallela, Ctenodonta, Encrinurus punctatus, etc. Prof. Groom remarks that the May Hill beds on the north of Midsummer Hill are separated from the gneissic series by a well-marked band of hard Cambrian conglomerate and quartzite, which he terms the Hollybush Conglomerate and Quartzite.^ Further north the May Hill beds occur at Swinyard Hill, south of the Herefordshire Beacon. Over- lying them at Malvern the Rev. W, S. Symonds observed a group of grey and purple shales, ' Woolhope Shales,' about 350 feet thick, which probably represent the Tarannon Shales of Montgomeryshire. In the Lickey Hills, as at Malvern, a long period elapsed after the deposition of the Cambrian quartzite, ' of which no record remains in the form of sediments, but during some portion of which the quartzite and Barnt Green rock were compressed and folded by earth-movements,' followed by faulting. Slow subsidence set in when the May Hill or Upper Llandovery grits and Wenlock Shales were laid down.^ Here the May Hill beds, which occur at Rubery, consist of coarse reddish sand- stone with casts of Pentamerus and other fossils, and they are overlaid by the Lower Wenlock shales and flags, including a band of limestone from which Mr. W. Wickham King obtained a number of fossils. These indicate a local representative of the Woolhope Limestone.^ The Woolhope Limestone which takes its name from Woolhope, near Hereford, comprises impure and nodular limestone and shale. It occurs at North Malvern and has been well exposed near the Wych. Many trilobites of the genera Illcenus, Phacops, Acidaspis, Encriiiurus and Calymene occur, and fine specimens were obtained during the ex- cavation of the Malvern and Ledbury tunnels. In the region near Dudley the rock is known as the Barr Lime- stone, from Great Barr near Walsall, a locality from which the charac- teristic trilobite, Illcenus barriensis, was first brought into notice. The Wenlock Shales consist mainly of soft grey shales, but they contain thin nodular layers of limestone. As a rule they are highly fossiliferous and yield the corals, Favosites gothlandica and Heliolites inter- stincta ; the brachiopods, Orthis elegantula, Strophotyiena rhomboidalis and Atrypa reticularis ; and the trilobites, Phacops caudatus, Encrinurus punctatus, etc. Many examples were obtained from near the mouth of the Malvern and Ledbury tunnels, where, as observed by Prof. Groom, the shales are faulted against the Old Red Sandstone.* The shales are usually exposed on the slopes and borders of the valleys. The Wenlock Limestone is a more or less concretionary limestone, and it contains large nodules of carbonate of lime. It is in many places exceedingly fossiliferous, as in the quarries at Colwall Coppice and the Winnings near Malvern, and in other exposures on Watts Hill and near ' Quart. Journ. Geol. Soc, vol. Iv. p. 139. W. Gibson, Summary of Progress of Geological Survey for 1897, p. 69. ^ Lapworth, Proc. Geol. Assoc, vol. xv. p. 357.

  • Quart. Journ. Geol. Soc, vol. Ivi. p. 147.