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GEOLOGY the local marls continue to furnish the material for the vessels in which the pottery is baked in the kilns in addition to being extensively used for other purposes. The fauna indicates the conditions under which the strata were deposited ; for, excepting Entomostraca, which constitute three or more thin bands of impure limestone, and a few fishes, the animal life consisted of the delicate thin valved mollusc Antbracomya pbillipsi, met with in countless numbers in the Blackband Ironstones. The flora, occasionally rich in species and numbers, partakes, according to Mr. Kidston, of a transitional character between Middle and Upper Coal- measures, thus further illustrating the gradual passage of one stage into the other. The Etruria Marls, which succeed, consist almost exclusively of red and mottled marls exceeding i,ooofeet in thickness in the central area. Thin bands of green grits, apparently derived in great part from the breaking down of igneous rocks, are interstratified at intervals. Only one locally developed coal seam has been met with, and excepting two thin beds of limestone containing the serpula Spirorbis the entire group consists of practically unstratified red marls. The Newcastle-under-Lyme Series conformably overlying the Etruria Marls shows, as far as the colour and nature of the material is concerned, a return to the conditions of the Blackband group. Grey sandstones and shales, in which lie four thin seams of coal, constitute almost the entire bulk. Plant remains are numerous, including the characteristic Upper Coal-measure fossil, Pecopteris arborescens, but associated with others of Middle Coal-measure age. Two thin bands of limestone with Entomostraca and a minute shell (Anthracomya calcifera) which are exposed in the marl pits between Etruria and Longport, invariably commence the sequence. In the Keele Series? into which these grey strata graduate upward, we again find rocks of a brilliant red colour, mainly red sandstones with intercalated red marls, among which at intervals thin beds of limestone with Entomostraca are interstratified. The flora, though badly preserved, as in most red rocks, contains species having a wide range throughout the Coal-measure period. For how long the Carboniferous period con- tinued beyond the record contained in these red rocks remains uncertain, since the strictly unconformable Triassic rocks conceal the top beds of the Keele Series or whatever strata may elsewhere succeed, and thus the legend in North Staffordshire abruptly terminates. THE SOUTH STAFFORDSHIRE COALFIELD The Carboniferous strata of this coalfield are arranged in a dome possessing a length of about 23 miles and a breadth of 6 miles. This main anticline, broken by three subsidiary folds, constitutes the Dudley, 1 This group was formerly placed in the Permian System. The reasons for the classification here adopted will be found in a paper by the author, <%uart. Journ. Geol. Sue. Ivii. 256 (1901), and in the 'Geology of the Country around Stoke-upon-Trent ' (Mem. Geol. Survey), pp. 45-7 (1902). 15