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 A HISTORY OF STAFFORDSHIRE ously mentioned, is the one above the Crabtree Coal ; the highest occurs only a few yards below the Ash Coal, while the remainder are found at intervals. In the highest band that above the Gin Mine Coal Mr. John Ward collected over twenty different species ; in the other bands Goniafites, Lingu/a, Pterinopecten, Posidoniella occur most frequently, and include some of the species of the Pendleside Series. As might be expected plant remains are not infrequent, though met with most abundantly on certain definite horizons. Among these Neuropteris heterophylla^ Alethopteris loncbitica indicate, according to Mr. R. Kidston, a low horizon throughout the Coal-measures of Great Britain. 1 The strata between the Ash and Bassey Mine Coals (Middle Coal- measures) by their strict resemblance in colour, texture, composition and by their stratigraphical conformity to the rocks below denote the continuation of similar conditions. The coal seams number over four- teen, representing a collective thickness of nearly 50 feet of coal. The quality however is inferior to the seams of the lower sub-division, though they are of great value to the potter in baking his wares, and being near the surface over a large portion of the area are in great request. The Middle Coal-measures contain several bands of ironstone, but of these only the semi-blackband, laminated Chalkey Mine Ironstone is raised in any quantity. The number and variety of fish remains is extraordinary, especially in the shales associated with the Winghay or Knowles Ironstone of Longton and Fenton ; with them the remains of amphibia are sparingly associated. The mollusca are abundant in the lower portion, but become gradually rarer towards the summit. The flora, notably on the horizon of the Great Row Coal, is particularly rich. The strata above the Bassey Mine Coal (Upper Coal-measures] belong to a different class of sediments, being made up chiefly of red sandstones and marls, among which grey rocks retain a definite but quite subordinate position. Coal seams are thin and lie on widely separated horizons, but bands of earthy limestone, crowded with Entomostraca and very rare in the inferior sub-divisions, become a marked constituent. Four distinct groups of rock individualize the Upper Coal-measures. In the lowest (Blackband Series] the material remains much the same as in the Middle Coal-measures, but there is a tendency for red marls to be developed along definite horizons. Several bands of Blackband iron- stones frequently exceeding 4 feet in thickness, readily calcined and rich in metallic iron, render the group of great economical importance ; while the associated grey marls, along whose outcrop the pottery towns have gradually extended, may be said to have initiated the pottery trade. Even now, when clays foreign to the district have come into general use, 1 The organic contents as a whole have been fully dealt with by John Ward, Trans. North Staff. Inst. Mining Engineers, vol. x. (1890), and Proc. North Staff. Field Club (1893-4). For the plants see R. Kidston, Trans. Roy. Soc. Edin. vol. xxxv. (l 891) and Proc. Royal Physical Society Edin. vol. xii. (i 893-4). The Lamellibranchs are described by Wheelton Hind, Palaontografhical Society, vols. xlviii.-l. For a recent account of the marine beds the reader may consult J. T. Stobbs, Tram. North Staff. Field Club, vols. xxrv., xxxvi. and Trans. Fed. Inst. xxii. 229 (1902).