Page:VCH Herefordshire 1.djvu/70

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A HISTORY OF HEREFORDSHIRE Hereford itself is built upon gravels, but below them are Old Red rocks which are low down even in the Lower Cornstones. At Lugwardine, sand- stones, on about the same horizon as those exposed in the cuttings on the Hereford and Shrewsbury Railway between the city and Dinmore, were once actively worked. From most of the localities mentioned above, some fish- remains have been procured, and, as long ago pointed out by Scobie, they are not nearly so rare as is generally supposed. The Lower Cornstones, capped with beds paralleled by Symonds with the Rowlstone Beds, compose many of the picturesque hills, such as Lady Lift, Wormsley, and Robin Hood's Butts, in the vicinity of Weobley, the valley-bottoms in many cases being in lower beds than the Lower Cornstones. The lowlands around Leominster are in the lower beds of the Lower Cornstones, from which many specimens of Eucephalaspis Agassizi have been obtained ; while the hills which break the monotony of the lowland are formed of the higher beds of the Lower Cornstones, which have likewise yielded many fish-remains, for example, Xenaspis Salweyi, Z. Lloydi, and Pteraspis rostratus. In the Bromyard district, where a similar configuration due to like causes obtains, fish-remains were formerly frequently found, but now most of the quarries are abandoned. It was in this neighbourhood that Salwey obtained the Tjenaspis which was called after him, Z. Salweyi?'^ Beds belonging to the Lower Division of the Old Red occupy a consider- able tract of country to the south of Bromyard, and masses of cornstone disconnected by denudation give rise to characteristic scenery. Rocks of the Cornstone Stage occur in a bay-like expanse around Colwall, and stretch southwards in a strait-like tract between Ledbury and the Woolhope inlier. Near Stifford's Bridge to the north of Cradley are certain sandstones that have been largely quarried for building-purposes in Malvern, which Symonds paralleled with his Rowlstone Beds. They have yielded few fish- or plant- remains ; but some sHghtly lower beds in the same neighbourhood proved very fossiliferous, yielding to Mr. Gill many of the fish now in the Museums of Worcester and Malvern, and to Professor Ray Lankester the tail of a Pteraspis with scales attached. The Brownstones comprise two divisions — an upper, consisting of a series of red marls overlying chocolate-coloured sandstones ; and a lower, made up of reddish and grey sandstones, marls, and cornstones. In the aggregate they measure between 1,200 and 1,500 ft., but contain very few organic remains ; indeed, from the Brownstones proper, fragments oi Pteraspis and Cephalaspis are all that have been obtained. The Brownstones are well developed in the Black Mountains, but, accord- ing to Symonds, in the hills of the Forest of Dean between the Great Doward and Mitcheldean, they have ' very much thinned out.' They were no doubt once continuous across the Ganerew district, but— together with the Upper Old Red Beds — have been removed by denudation. The bottom beds of the cornstones, which are associated with the Brownstones proper, are seen at Cusop, near Hay, and Rowlstone, and from the former locality Symonds procured plates of a Pteraspis and an ichthy- '* See Symonds, Flora (1889), p. xviii ; Records of the Rocks, pp. 218-19 ; Quart. Journ. Geol. Soc. xiii (1857), p. 283 ; ibid. XV (1859), p. S°3 ; ^^A £>■■ ^"'"- '864- 22