Bones of Mammalia on a Deposit at Folkestone Containing
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Downloaded from http://jgslegacy.lyellcollection.org/ at Duke University on November 29, 2013 Quarterly Journal of the Geological Society On a Deposit at Folkestone containing Bones of Mammalia Samuel J. Mackie Quarterly Journal of the Geological Society 1851, v.7; p257-262. doi: 10.1144/GSL.JGS.1851.007.01-02.44 Email alerting click here to receive free service e-mail alerts when new articles cite this article Permission click here to seek permission request to re-use all or part of this article Subscribe click here to subscribe to Quarterly Journal of the Geological Society or the Lyell Collection Notes © The Geological Society of London 2013 Downloaded from http://jgslegacy.lyellcollection.org/ at Duke University on November 29, 2013 THE QUARTERLY JOURNAL OF THE GEOLOGICAL SOCIETY OF LONDON. PROCEEDINGS OF THE GEOLOGICAL SOCIETY. MAY 14, 1851. Samuel J. Mackie, Esq., was elected a Fellow. The following communications were read :-- I. On the DISTRIBUTION of the FLINT DaI~ of the SOUTH-EAST of ENGLAND, on the FLANKS of the WEALD, and over ~he SURFACE Of the SOUTH and NORTH DOWNS. By Sir RODEalCK I~PEY MURCHISON, G.C.St.S., F.E.S.G.S. &e. [This paper will appear in the next Part.] 2. On a DEPOSIT at FOLKESTONE containing BoNEs of MAMMALIA. By SAMUEL J. MACKIE, Esq., F.G.S. THE high ground of the Lower Greensand at Folkestone forms a gently inclined plain, stretching inland as far as the hills of the Chalk- escarpment. Between this plain, which constitutes the West Cliff, and the East Cliff or Copt Point, there is a valley*, from 40 to 90 feet deep, in which a considerable part of the Old Town is built, extend- ing in a curving direction through the village of Ford (at which place it is crossed by the viaduct of the South Eastern Railway) towards * See View of Folkestone in Dr. Fitton's Section of the Coast, Trans. Geol. Soc. N. S. vol. iv. Pl. 8. VOL, VII.--PART I. T Downloaded from http://jgslegacy.lyellcollection.org/ at Duke University on November 29, 2013 258 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May14, the escarpment of the hills, which skirt, as it were, the sandstone- plain of the West Cliff. Fig. 1 .--Plan of a part of the Town of Folkestone. a. Section of the Bone-bed, &c., exposed at Mr. Craxford's house, on the Bayle (see fig. 3). b. The lowest point at which the Brick-earth occurs. ~ Section of the Brick-earth and angular.flint~gravel, exposed at London Street (see fig. 4). 9Section of the Brick-earth at Porter's Saw Mill. e. Section of the Bone-bed at the Town Sewer on the Bayle. The shaded portion of the Bayle indicates the extent of the Bone-bed. At the south-eastern corner of this plain (at an elevation of 110 feet above low-water-mark) on the top of the West Cliff, under the Battery, and lying immediately on the upper beds of the Lower Greensand, which are of loose disintegrated sand, is a deposit, from 1 to 9 feet thick, consisting of flint pebbles and boulders; Downloaded from http://jgslegacy.lyellcollection.org/ at Duke University on November 29, 2013 1851.] MACKIE ON THE FOLKESTONE BONE BED. 259 the former are small and round, the latter generally angular and slightly worn. With these are associated fragments of compact ferruginous sandstone, and the whole is intermixed with loamy sand and calcareous gritty marl. The marl, for the most part, forms the upper portion of the bed, which extends on the face of the cliff for a distance of 320 feet. The bed may be here seen following the irregularities of the uneven surface of the rock on which it rests, and distinctly displaying the variations in its thickness (see fig. 2). It contains, generally in the lower part, a considerable number of the remains of Elephant, Ox, Stag, Hyeena, Hippopotamus, Irish Deer, &c., and, in the marly portion, numerous specimens of two or three species of Helix* : no fluviatile molluscs have hitherto been observed. The Bones and Shells, however, are found both in the gravel and in the calcareous marl above it. This bed appears to be cut off by the valley, previously referred to, towards which it thins out altogether ; and no traces of organic re- mains have been found on the east side of the town. On the west it thins off beneath a bed of dark brown clay, much resembling the superficial brick-earth that is found on the surface of the plain, and at many places in the neighbouring country. The shaded portion, comprising the Bayle and the Battery, on the accompanying plan (fig. 1) shows the extent of the deposit, as above described. But its distribution is much more extensive, if we regard this bed as being intimately connected with the flint and iron-sandstone Drift which covers the tops of the Chalk-hills, and with the Brick-clay found on the Gault and Greensand plain on which this Bone-bed lies. Fig. 2.--Section of a part of the West Cliff', Folkestone. The Section, fig. 2, represents the "Bone Bed" as seen on the face of the West Cliff (see Plan) ; and the Section, fig. 3, taken at a right * First observed by Mr. J. Morris, F.G.S. T2 Downloaded from http://jgslegacy.lyellcollection.org/ at Duke University on November 29, 2013 260 PROCEEDINGSOF THE GEOLOGICAL SOCIETY. [May 14, angle to the foregoing, was exposed in the excavation lbr Mr. Crax- ford's House. (See Plan, fig. 1, a.) Fig. 3.--Part of the Section exposed in digging the .foundation of Mr. Craxford' s House. Length 35 feet ; height 14 feet. The base of the Section is on the Road, 105 feet above low-water mark. The whole of the "Bone Bed" appears to have been subjected to the action of water, as the flints and grit-boulders, although an- gular, are partially worn, and the chalk-nodules and softer pebbles are completely rounded; the stratification, also, of the marl, sand, and boulders follows the irregularities of the Lower Greensand on which they rest. There is no evidence that this deposit was of marine origin, marine remains* not having been found in it ; on the other hand, the bones of Mammals and the Snail-shells, with which it abounds, would in- dicate its fluviatile or lacustrine orion. The presence of a breccia of chalk-flints, if so it may be termed, at this spot is somewhat singular, no flinty chalk occurring at a less distance than six miles to the north or east, and the grey chalk rising between that member of the Cretaceous group and the "Bone-deposit," and forming the highest ground of the whole district. The finer portions of calcareous marl and loam would, to a great extent, appear to have been derived from the waste of the Chalk, the marl possessing all the usual mineral characters of such sediments ; and I have also found the little TereSratula rigida, so characteristic of the Chalk, in the sandy loam. A microscopic investigation carries this view still further, and favours also the idea of the probable iden- tity of age and origin of the Bone-bed with the Brick-clay and Drift ; the calcareous marl of the first-named deposit abounding with Fora- minifera and other microscopic organisms, many forms of which are * Excepting foraminifera, &c., of the Chalk, obviously derived from detrital action. Downloaded from http://jgslegacy.lyellcollection.org/ at Duke University on November 29, 2013 1851.'] MACKIE ON THE FOLKESTONE BONE BED. ~61 immediately recognized as the ordinary species of the Chalk; the same also being the case with the Brick-earth and the clayey portions of the Drift. Mr. Rupert Jones, who at m y request~ examined myw prepared "slides," as well as a small quantity of the marl and brick-earth, has kindly furnished me with the following lists. From the Calcareous Marl of the Bone-bed :-- Verneuilina tricarinata. Prismatic fragments of Inoceramus. Textularia globosa, trochus, and others. Fragments of Echinodermata. Polymorphina ? Ossicles of Apiocrinites. Bulimina variabilis and another. Valves of CythereUa ovata and C. trun~ Rosalina. cata. Globigerina cretacea. Bairdia subdeltoidea and B. Har- Cristellaria rotulata and another, risiana. Rotalia globosa. - Cvthere Hilseana (? derived from Nodosaria. Chalk-marl). Single cells, ovoidal and globular, = Oo- lin~e ? and portions of other Forami- nifera. From the Brick-earth of Gambrill's Pit, } mile N.W. of the Bayle :-- Rotali~e, Rosalind, and single ovoidal Helix. cells. Pupa. In the Drift of Folkestone Hill, Chalk-organisms are plentiful. Two excavations on the West Cliff, one for Mr. Craxford's House (see Plan, fig. 1, a), the other for the Town-sewer on the Bayle (see Plan, fig. l, e), have afforded me all my present collection of bones and shells from this deposit. List of the Organic Remain~from the "Bone Bed." BoxEs ANY Hoa~s. Megaceros Hibernieus. Elephas primigenius. Equus. Hippopotamus major. Hyaena spel~ea~ Bos primigenius. SHELLS. urns. longifrons. Helix nemoralis. Cervus elephas. ~ eoncinna. Prof. Owen kindly inspected and determined a large collection of the bones exhibited to the Society. The list comprises also some other specimens determined by H. Turner, jun., Esq. The Drift and Brick-earth.--The probable relation of the mam- maliferous deposit above-described with the Drift was suggested to me by Sir Roderiek I. Murchison,--the occurrence of angular flints being singularly characteristic in both cases, to which fact the follow- ing example, fig. 4, one out of the many that could be given, has especial reference.