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). 



