Page:Quarterly Journal of the Geological Society of London, vol. 33.djvu/734

630 (6) South-Staffordshire Coal-field. Thickness — feet. Stage G. Tipper Coal-measures. — Eed and mottled clays, red and grey sandstones, and gravel beds 800 Stage F. Coal-measures. — Shales, sandstones, clays, with coal-seams and ironstones above the New-mine ironstone. Fish-remains, Anthra- cosia ( Unio) 200 Stage E. Lower (or Gannister) Beds. — Shales, sandstones, with coals and ironstone (" New mine " and " Pennystone"), with marine fossils — Productus scabriculus, Aviculopecten scalaris, Lingula mytiloidcs, Conularia quadr [sulcata, &c 200 As these beds rest directly on the Upper Silurian rocks, Stages A, L, C, and D are not represented. The marine fossils from the " New- (or " "White- ") Mine " and " Penny stone " ironstones are similar to those from the ironstone of the same name in the Coalbrook-Dale Coal-field ; both are near the bottom of the Coal-measures, and mark a definite marine horizon. Along with the truly marine genera, bivalves of the genus AntJira- cosia (?) are sometimes found ; but the late Mr. Salter states that " it appeared that generally where undoubtedly marine shells were present these so-called Uniones were absent"*. The commingling of these shells is not confined to this district, but has been observed in Lancashire, and probably indicates the alternation of marine and estuarine conditions in certain localities. (7) Leicestershire Coal-field. All the stages are here represented, though in diminished dimen- sions as compared with the coal-districts to the north. Thickness — feet. Stage G. Upper Coal-Measures. — Coarse grits of Moira and Newall, with Stembcrgia, resting unconformably on Middle Coal-measures t 20 to 50 Stage F. Middle Coal-measures. — Sandstones, shales, and clays, with several coal-seams. Plants; Anthracosia {Unio), Cythere or Cypris 1500 Stage E. Lower Coal-measures. — Shales and sandstones &c., with a few thin seams of coal below the " Heath-end " coal §. Shells of marine genera have recently been discovered 1000 Stage D. Millstone Grit. — Coarse grits, &c 50 Stage C. Yoredale Beds. — Shales, &c 25 Stage B. Carboniferous Limestone. t The late Eev. W. II. Coleman, ' The Geology of the Leicestershire Coal • field ' (Mem. Geol. Survey), p. 56. § These beds are chiefly known from boring records.
 * Jukes, ' South-Staffordshire Coal-field,' 2nd edit. p. 58.
 * Mammatt, ' Geological Facts,' &c.