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 A HISTORY OF SUSSEX the surface than would otherwise be expected, and we may there find a counterpart of the Palaeozoic ridge under Dover and London. Experi- ments at Dover however have not yet been so successful as to encourage deep borings in Sussex, and near London rocks older than the Coal Measures have been met with beneath the Cretaceous. The only deep boring on the south side of the Wealden anticline is that sunk at the Brighton Industrial School at Telscombe, where Lower Greensand was touched at 1,280 feet from the surface, but was only penetrated to a depth of about 5 feet. It is unfortunate that this boring was not carried a few feet lower, for within 20 feet the Lower Greensand would probably be pierced. What comes below is quite uncertain, and the determination of this point would throw much light on Sussex geology. Owing to the absence of Lower Greensand cliff sections in Sussex few fossils have been found in this division compared with the prolific fauna of Kent and Hampshire. Selmeston yields drifted pine-wood perforated by boring molluscs. At Pulborough and Parham marine mollusca have been obtained from the Sandgate Beds, and at Pulborough the Hythe Beds also have yielded a good many species and the Folke- stone Sands contain a few. These fossils are mainly bivalve shells, few of the characteristic ammonites or other cephalopods and few gasteropods having yet been found in Sussex. The porous strata of the Lower Greensand are succeeded by a mass of stiff dark-blue clay known as Gault. This comes to the surface in the belt of flat heavy land which separates the sandy ridges of the Lower from the similar ridge formed by the Upper Greensand on the south. In Sussex the Gault reaches the exceptional thickness of 300 feet, and is nearly everywhere fossiliferous, though owing to the absence of cliff sections and the rarity of clear inland exposures fossils are not so readily obtained as at Folkestone. At the base is found a band of scat- tered phosphatic nodules, and this band seems to separate the true Gault from the Lower Greensand below — though the upper part of this latter (the only part preserved at Eastbourne) may be nothing but a gravelly base to the Gault, equivalent to beds with Ainmonites mammillatus found elsewhere. Low down in the true Gault at Eastbourne Ammonites laiitus, a characteristic fossil of the Lower Gault, has been found ; but the principal locality for Lower Gault fossils in Sussex is Ringmer, from which place Mr. Jukes-Browne gives a long list of fossils, cephalopods being particularly abundant.* At St. Anthony's Hill near Eastbourne Mr. F. G. H. Price discovered another set of fossils, which prove the Gault there seen to belong to the lower part of the Upper Gault. The highest beds of all are sometimes well exposed on the foreshore opposite Eastbourne, and they have been carefully examined below the Wish Tower by Mr. Price and Rev. H. E. Maddock, who there collected many fossils, including such characteristic Upper Gault forms as Am- monites rostratus, A. varicosus, A. auritus and Anisoccras [Hamites) armatum. > 'The Cretaceous Rocks of Britain,' i. I 2 I, Memo'in Gcol. Siinry (1900). 8