Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/325

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1870.] LLOYD AVON AND SEVERN VALLEYS. 217


Part II. The Superficial Deposits of the Severn valley and adjoining District.

Introductory Remarks. — In order to carry out the object I had in view at the commencement, of making the descriptions of the facts belonging to the subject of this paper in a great measure supplementary to those of others, I shall limit myself, as much as possible, to a statement of such of them as I believe have not yet been brought under the notice of the Society.

Literature of the Subject. — Sir Roderick Murchison, I believe, first brought under the notice of geologists, in the ' Silurian System,' the discovery of marine shells and mammalian remains in the drift of the Severn Valley, near Worcester ; but, as far as I am aware, no detailed account of the facts connected with the nature and mode of occurrence of the gravels and clay of the Severn valley and its neighbourhood was published until a paper appeared (in the Quart. Journ. Geol. Soc. 1864, vol. xx. page 130) entitled " Notes on the Drift Deposits of the Valley of the Severn in the neighbourhood of Coalbrook Dale and Bridgnorth," by Mr. Geo. Maw, F.G.S., in which, after mentioning the names of other geologists in the same field, the author described some remarkable sections of deposits containing marine shells.

At page clxvi of the Strickland Memoirs the following passage occurs : — " Dr. Falconer conceives that there exists in the valley of the Severn an old fluviatile Pliocene deposit of great extent, containing the usual association of Pliocene mammalia — Elephas antiquus, Hippopotamus major, Bison, Deer, &c, with freshwater shells ; and also overlying beds of gravel, which are described as Estuarine, and drift-gravel containing a few marine shells ; Cardium and Turritella, and the mammalian remains of the Glacial period — Elephas primigenius, Rhinoceros tichorhinus, Reindeer, Horse, &c." See Dr Falconer's views (Proc. Geol. Soc. 1856-57, page 5, &c). Wishing to refer, if possible, to the original remarks of so eminent an authority as the late Dr. Falconer, I sought for the reference given, but without finding there any allusion to the subject of the foregoing quotation. I then wrote to Sir W. Jardine, who informed me that the reference alluded to was to be found in vol. xiii. page 307 of the Journal ; but up to the present time I have failed to discover it.

Referring to the account of the Severn valley and its geological features between Shrewsbury and Bridgnorth, given in the paper by Mr. Maw, already mentioned, I need only add that below Bridgnorth the river continues its general S.S. -easterly course as far as Tewkesbury, passing over beds of New Red marl for a great part of the distance. As we approach the town of Worcester the valley opens out into a broad undulating vale, about 7 miles in width, extending from the base of the Malverns on the west to the narrow watershed on the east, which separates it from the valley of the Avon. The tide rises up as far as Tewkesbury ; but the Severn, like its affluent, the Avon, is much altered in its natural course by locks and weirs.

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