OF THE CARBONIFEROUS SERIES. 627 Maximum thickness. feet. Stage G. Upper Coal-measures.— -Shales, sandstones, and limestones oH ,/.«„ Ardwick, with Spirorbis, Cythere, and fish. A bed of black-band I , to rnnwpsii. joeiow tnese rea sandstones, | ( shales, and thin coal-seams* ironstone, with Anthracosia Phillipsii. Below these red sandstones, f 1400 to 2000 Stage F. [Middle] Coal-measures. — Sandstones, shales, clays, and thick j 3000 coal-seams, from ihe " Worsley Four-feet coal " to the flags below the I to Arley mine. Anthracosia, Anthracomya, &c J 4000 Stage E. Gannister Beds. — Flagstones, shales, and thin coal-seams, one" of which has a hard siliceous floor (Gannister). Goniatites Listen, Nautilus, Aviculopecten papyraceus, Lingula squamiformis, Anthra- cosia, Spirorbis, fish, &c Stage J). Millstone Grit. — Coarse grits, flags, and shales, with a few thin 1 3500 coals. Marine shells: Aviculopecten, Posidonomya Gibsoni, Goniatites I to reticulatus, Orthoceras, &c J 5000 Stage C. YoredaJe Beds. — Shales principally, with thick beds of grit in 1 2000 the centre (Yoredale grit). Goniatites excavatus and several other I to species, Modiola, Myalina, Discina nitida, Productus J 4000 Stage B. — Carboniferous Limestone, &c. (2) Yorkshire and Derbyshire Districts. feet. Stage G. Upper Coal-measures. — Reddish sandstones, with plants (Ack- worth rock), and " red rock of Rotherham " resting unconformably onStageFt 54 Stage F. Middle Coal-measures. — Sandstones, shales, clays, with iron- stones and coal-seams. Anthracosia &c. ; fish 2500 Stage E. Lower {or Gannister) Beds. — Flagstones and shales, with thin coals, and Gannister-floor. Aviculopecten papyraceus, Goniatites, Posidonomya, Crthoceras Steinhaueri, Nautilus Bawsoni 1000 Stage D. Millstone Grit. — Coarse grits, flags and shales 2000 Stage C. Yoredale Beds — Principally shales, with grit in centre. Ma- rine fossils 2000 Stage B. — Carboniferous Limestone about 5000 Base not seen. (3) North- Staffordshire District. feet. Stage G. Upper Coal-measures. — Brown and reddish sandstones, red and mottled clays, and shales, thin coals and ironstones down to the " red mine "-band. A bed of limestone at Fenton, with Spirorbis carbo- narius, and Anthracomya Phillipsii (Shelton) 1 500
- Marine shells occur in a band in this position at Ashton-under-Lyne — Avicido-
pecten fibrillosas (Salter), Ctenodonta, Goniatites, Nautilus precox (Salter), Dis- cites rotifer (Salter). These were discovered by my colleague, Prof. A. H, Green ; see ' Geology of Oldham,' Mem. Geol. Survey. t Assuming that the " Ackworth rock " is the " red rock of Rotherham," which Mr. Aveline describes as unconformable to the Coal-measures underneath. The plants are Lepidodendron acideatum, L. obovatum ?, Catamites Suckovii, and Sigillaria, as determined by the late Mr. Salter, " Geology of Parts of Notts, York, and Derby," by W. T. Aveline, F.G.S., Mem. Geol. Survey (1861).
