Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/394

at this quarry. He says that the passage of the Upper Ludlow rock, with its " bone-bed," may be observed here into the yellow Downton beds, succeeded by red marls, precisely similar to those in the Ledbury Tunnel. On my first visit to this spot they were not exposed, and were not visible at a later one ; and the pit has not been worked now for many years. I cannot, therefore, say decisively whether the " olive shales" are present there in situ or not. The " bone-bed" here and at Gamage Ford probably belongs to the lower " bone-bed" which, in Shropshire, is present in the higher portion of the Upper Ludlow, not far below the thicker mass of the Downton sandstone; while another and upper one occurs about the middle of the " olive shales," but it is apparently wanting here. I searched in vain for these " passage-beds " more to the south, near Soller's Hope, where they might be expected to come in, unless a sandy marl, of which a section may be seen in places along the brook which traverses the lower ground, belongs to them. It contains a small Orthis and Beyrichia, but it most likely belongs to the Ludlow formation. They may or may not be continuous round the whole of the outer limit of the Silurians in the district under review, and I think it probable that here and there they might be detected in roadside cuttings throughout the whole of this area ; I hope, at some future time, to be able to investigate this more closely. At any rate, a more considerable extension has been shown, especially to the east of Woolhope ; and the presence of the " olive shales," exactly identical lithologically and, to a certain extent, zoologically with the "olive shales" near Ludlow and other places in that neighbourhood, is distinctly proved. On the west, north-west of Woolhope, and south towards Fownhope, there is less chance of observing those " passage-rocks," if they occur there, because there is a very considerable quantity of drift, which would overlie and conceal them. This larger mass of drift, derived mainly from the denudation of the Silurians adjacent, was first noticed by my friend the Rev. F. Merewether, Vicar of Woolhope, who, in a short paper read to the Woolhope Naturalists' Field Club, in October 1870, has shown a thicker and wider extension of drift in this direction, which had not been before noticed. In many spots these " olive shales " are not exposed, though they may be present in situ ; but, from their soft and friable nature, a considerable quantity has no doubt been denuded, unless protected by the overlying sandstones. As they pass downwards into a more sandy stone, it is probable that there is some sandstone below ; to what extent or thickness, it is impossible to ascertain ; but it cannot be very thick in the only two places where I have observed them, as at Perton they rest almost immediately on the Upper Ludlow, and at Hillfoot, though not directly overlying it, at least not shown in the section there, the Ludlow shales crop out not far from them. The subordinate sandstone would then seem to be of far less thickness than the more massive sandstone at Downton, Shobden, and elsewhere. The " olive shales" are, no doubt, the equivalents in time of the