Page:VCH Herefordshire 1.djvu/68

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A HISTORY OF HEREFORDSHIRE quoted Geikie's view of the genesis of the Old Red Sandstone of this county in a ' Welsh Lake.' Symonds was opposed to the ' lake-theory,' and so are Professor E. Hull*' and Mr. A. J. Jukes-Browne.** As the last geologist remarks, if the two areas of sedimentation were separated, it must have been by a barrier, and such being the case some evidence should remain of that barrier. But as far as is known at present there is not. G, H. Piper apparently believed in its accumulation in a bay and, although the question is admittedly an open one, this seems very probable. Of recent years little or no serious work has been accomplished in connexion with the Old Red Sandstone of this county ; but thanks to the pioneer work of Murchison, supplemented by many local details collected by Dr. Lloyd, who was apparently the first to find fish-remains in these strata, Salwey, Lightbody, Dr. D. M. McCullough, the Rev. T. T. Lewis and W. S. Symonds, R. Banks, G. H. Piper, Henry Brooks of Ledbury, and others ; and to Dr. Henry Woodward,*^ Professor Ray Lankester and J. Powie,°®J. W. Salter, and Dr. H. Traquair,** who have figured and described many of the fish- and crustacean- remains, the fauna is fairly well known. The Herefordshire Old Red may be divided then, as in other regions, into two parts, an Upper and a Lower. For descriptive purposes the Lower Division may be separated into Brownstones and Cornstones, the latter embracing, in ascending order, the Pteraspis Beds, Lower Cornstones, and Rowlstone Beds. Lower Division. — It is beds belonging to this division and to the Cornstone-Stage portion that constitute the rock-floor of by far the greater part of Herefordshire. They extend from the foot of the lofty Black Mountains and the hills of the north-western fringe of the Forest of Dean, northwards, occupying a wide extent of country in the southern portion of the county and environing the Silurian inliers of Woolhope, Hagley, and Shucknall Hill ; but become more restricted in extent in the northern, where rocks of greater antiquity rise up from beneath them on the east in the Malvern district and on the north-west in the Ludlow-Huntington district. The Pteraspis Beds are sandstones. Although doubtless having a con- siderable superficial extent they have only been satisfactorily identified in the neighbourhood of Pontrilas, where they were exposed in a quarry and in the tunnel near the station, at Leyster's Pole or ' Sprowle,' and around Puddlestone. At the last two localities many fish-remains have been obtained. r i. r>i i The Lower Cornstones crop out in the lower slopes of the Black Mountains and cap Ewyas Harold Common. The rocks to which the term ' cornstones ' is appUed are impure hme- stones. Sometimes they are present as massive beds, furnishing blocks many tons in weight, and at others as nodules so small as to be suitable for working for gravel. In the days of Murchison the cornstones were burnt for lime, and he records that there was scarcely any part of the central districts where limekilns were not numerous. From an analysis of thirteen specimens e3 Quart. Journ. Geol. Soc. xxxvi (1880), p. 270. " jW. Building of the British Isles {^d.. 2, 1892), p. 98. " A Monograph of the British Fossil Cmstacea, Order Merostmata^A. Soc. 1 866-78) »« A Monograph of the Fishes of the Old Red Sandstone ofBrttam (Pal. Soc. pt. 1, 1868-70) : continued by R H. Traquair, pt. ii (in progress). 20