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 A HISTORY OF HEREFORDSHIRE authors — including the Downton Castle Sandstone and Temeside (or Ledbury) Shales. The most interesting bed, besides being the most important, is the Downton Bone-Bed, or if it be called after its characteristic gastropod, the Platyschisma-helicites Bed. For many years it was not realized that the Platyschisma Bed passes laterally into a 'bone-bed,' but such appears to be the case,^^ and in one form or the other it extends over wide areas at a comparatively uniform distance of 3 ft. above the Upper Ludlow Bone-Bed. The Downton Bone-Bed is exposed in the roadside near Forge Bridge and near the cottage at the Old Millrace weir. The Upper beds of Downton Castle Sandstone cap the cliff on the north bank of the Teme near Forge Bridge, but are more accessible in the quarries by the road-side and in Tin Mill Wood. In the Tin Mill Wood Quarry the bottom beds of the Temeside Shales are visible, and a little farther to the north-east, owing to the peculiar domical disposition of the strata, the higher beds are seen at a lower level in the cliff bordering the Old Millrace. Here the Olive Shales, representatives of which occur in the Woolhope district, can be studied. The ' Transition-Beds,' or Temeside Beds, have been observed at Richard's Castle, Ashley Moor, near Orleton, Mortimer's Cross, Croft Bank, and at Bradnor Hill. Richard Banks '^ studied these beds in the neighbourhood of Kington, and from the Bradnor Hill Quarry obtained Cyathaspis Banksi, and many species of Pterygotus and Eurypterus. At Ivy Chimney Quarry, also near Kington, the same geologist found the specimens of Pterygotus truncatus and P. Banksi that Huxley and Salter figured. The Hereford county-boundary takes in about half the area of two outliers of Temeside Beds lying to the west of the great fault. The larger is situated to the north of Presteign and is said to consist of thin-bedded sand- stones and deep red clayey ijiarls inclined at a high angle and having a north- north-east and south-south-west strike. The sandstone-beds have been worked in places. The small outlier, to the south of Presteign, is of similar formation.'* Malvern District. — Silurian rocks extend southwards from the Abberley Hills, along the western side of the Malvern Hills, to the neighbourhood of Eastnor, where their superficial extent has expanded. Murchison was the first to give a clear account of the Silurian rocks of the Malvern district ^^ ; but his essay was entirely eclipsed by that of Professor John Phillips, who contributed a most masterly account of this district on behalf of the Geological Survey.'^ Since then the beds have been studied by Symonds, Salter, and Professor Groom, and likewise by Dr. Grindrod, whose collections are widely known. The May Hill Sandstone forms a conspicuous escarpment overlooking on the west the diversified tract where the Cambrian Shales and associated igneous rocks occur. 5' Quart. Journ. Geol. Soc. Ixii (1906), pp. 195-220. " Ibid, xii (1856), pp. 93-100 ; Edin. New Phil. Joun. (1856), p. 240. '* Murchison, Silurian System (1839), pp. 191-2 ; Symonds, Records of the Rocks (1872), p. 217. ^ Silurian System (1839), pp. 410-14. '° Mem. Geol. Surv. ii pt. i (1848), pp. 57-101. 12