Page:VCH Warwickshire 1.djvu/50

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A HISTORY OF WARWICKSHIRE described by Beesley. 1 They consist of shales with bands and nodules of limestone, and contain the zone ammonites A. armatus, A. jamesoni and A. ibex, as well as numerous belemnites, the dart-like internal hard part of a cuttle-fish. Near Rugby the lowest beds of the Lower Lias were cut through by the Birmingham railway west of Church Lawford, and appear to consist of paper-shales instead of the usual limestones. But an excellent section of some 70 feet of the overlying limestones and clays belong- ing to the zones of A. angulatus and A. bucklandi is afforded by the Victoria quarry about a mile north-west of Rugby ; the beds which are worked for blue lias lime and cement have yielded remains of saurians, with ammonites, lamellibranch shells and crinoids. 2 In a pit north of Newbold Grange the beds are folded up into a sharp saddle or anticline. Several brickyards about Rugby and Hill Moreton afford sections of higher divisions with A. semicostatus, A. brevispina, etc. ; and a deep well south-east of Rugby proved 458 feet of Lower Lias beds. The two outlying patches of Rhaetic and Lias beds south-west of Henley-in-Arden and also that at Knowle have yielded various character- istic fossils, and the limestones were formerly worked. Insect limestones are present, and Brodie 3 records that at Knowle the ' firestones ' and ' guinea bed ' were formerly quarried by a shaft and yielded the usual fossils, of which may be mentioned A . planorbis, Ostrea tiassica, and bones of Ichthyosaurus. By the close of the Lower Lias period the sea had become shallower, and we find that much sandy matter was deposited ; this forms in part the Middle Lias. These beds consist of a lower series of bluish-grey micaceous marls and clays and laminated calcareous sands and clays with layers of limestone and calcareous sandstone ; these softer beds are over- lain by a rocky band of tough iron-shot and earthy limestone known as the Marlstone. 4 The latter especially is rich in fossils, and Ammonites spinatus and A. margaritatus characterize the rock, the former being restricted to the higher beds. In addition to these ammonites there are several species of belemnites, a number of lamellibranchs, and the star- fish-like Ophioderma egertoni and O. milleri. The Middle Lias enters the south-western edge of the county near Chipping Campden, where the Marlstone has been quarried at various points round Ebrington Hill ; the whole group there attains a thickness of about 150 feet. In the direction of Stow-on-the-Wold however this becomes reduced, and the bold escarpment gradually disappears. 6 It reappears however at Little Compton in the extreme south of the county, and thence can be followed north-eastwards towards Edge Hill. Sections in the Middle Lias were opened up during the construction of the tunnel on the Banbury and Cheltenham railway north of Chipping ' Proc. Warwickshire Nat. Club (1877), p. i. Woodward, op. cit. p. 163. Quart Journ. Gtol. Soc. xxi. (1865), 159 ; also xxx. (1874), 746. Woodward, op. cit. p. 185.

  • Howell in Hull's Geol. of Cheltenham,' Mem. Geol. Survey, p. 19.