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 A HISTORY OF WARWICKSHIRE sandy strata with concretions of calcareous sandstone, and these are capped in the Cotteswold Hills to the south by a brown marly and ferruginous limestone, 4 to 16 feet thick, abounding in remains of cephalopoda ammonites, belemnites and nautili and hence known as the Cephalopoda Bed. The rocks are characterized by the ammonites A. jurensis and A. ofa/inus, and by the bivalve Rhynchonella cynocephala, the fauna belonging partly to the Lias and partly to the Oolite, or in Professor Phillips' words, ' before the Liassic life has come to an end the Oolitic life has begun.' Around Ebrington Hill, on the western side of the Vale of Moreton, the Midford Sands are not exposed, being presumably concealed beneath the debris of the overlying beds. They are traceable however south- wards along the edge of the main Oolite tract to the vicinity of Stow- on-the-Wold, but north-east of that locality they are not to be identified. The Inferior Oolite consists of buff and brown oolitic and ferrugi- nous limestone with local beds of clay, marl and sand. 1 The character- istic zonal ammonites A. murcbisontz, A. humphriesianus and A. parkinsoni have not been found in Warwickshire. The few fossils recorded include bivalve shells such as Trigonia, Pecten and Terebratula, and the sea-urchin Clypeus ploti. The Inferior Oolite forms two small outliers on Ebrington Hill ; the rocks there consist of yellow and brown sandy and oolitic limestone, often banded with iron compounds, and they have been wrought for freestone. It is evident that while the marine limestones were being laid down the area was invaded by currents bearing much sand in sus- pension ; for Professor Judd records that in one section yellow and ferruginous sands of the type of the Northampton Sands can be seen to pass into oolitic limestone in a distance of 40 yards. 2 Crossing to the eastern side of the Vale of Moreton it appears that the county boundary just includes some of the Inferior Oolite and Great Oolite strata in the form of outlying strips and patches, extending from Little Compton to the vicinity of Compton Winyate. The In- ferior Oolite of this district comprises some very variable beds, consisting of calcareous sandstones and oolitic and sandy limestones, where the Cotteswold type passes into the Northamptonshire type. Our know- ledge of this area is largely due to the researches of Messrs. T. Beesley, W. H. Hudleston, E. A. Walford, and J. Windoes. Portions of the Inferior Oolite and of the succeeding Great Oolite were grouped together on the Geological Survey map as Northampton Sand, but it is now known that this formation belongs to the lower part of the Inferior Oolite. North-east of Bright Hill (south of Long Compton) the In- ferior Oolite is represented in part by the Clypeus Grit, the Northamp- ton Sand below resting directly on the Upper Lias. It may be of interest to note that the standing stones north of Little Rollwright, known as the 1 See H. B. Woodward, ' The Jurassic Rocks of Britain,' Mem. Geol. Survey, iv. 148. 22
 * H. B. Woodward, op. cit. p. 14.2.