Reporta and Proceedings — Geological Societij of London. 237 



and Beiun Bhreac. They are in contact with formations ranging 

 from the Lower Old Ked Sandstone to the Trias, and are later in 

 date even than the important faults of the area. They are made up 

 partly of fragmental volcanic materials, and partly of various 

 intrusive masses, confined within an almost unbroken ring of 

 intrusive rocks. In addition to igneous fragments, the clastic 

 volcanic rocks contain fragments derived from the surrounding 

 formations ; and also masses of shale, marl, limestone, and sandstone 

 belonging to formations not now found in sitii in the island. One of 

 these is several acres in extent, contains fossils, and is in part of 

 Ehjetic age ; a second is a fragment of Lias ; and a third is of 

 limestone and chert resembling the Antrim Cretaceous rocks, and 

 yielding fossils. The absence of Oolitic and older Cretaceous seems 

 to indicate a resemblance between a former succession in Arran and 

 that now seen in Antrim. If these fragments fell into the vent from 

 above, the igneous rocks must be of Post-Cretaceous age, and they 

 give an impressive picture of the amount of denudation which has 

 occurred since the period of vulcanicity. 



Part II.—" PaljBontological Notes." By E. T. Newton, Esq., F.R.S., 



F.L.S., F.G.S. 



The masses of Rba^tic strata yield Avicula contorta, Pecten 

 valoniensis, Schizodiis (Axiniis) cloaciniis, etc. ; those of Lower Lias, 

 Gryphcea arcuata. Ammonites angulatus, and new species of Niiculana 

 and Tancredia, which are figured and described. Thin slices of the 

 Cretaceous limestones prove tn be very like those of the Antrim 

 Chalk, and the rocks yield determinable Foraminifera, Inocerami, 

 Sponges, and Echinoderms. 



2. " On the character of the Upper Coal - measures of North 

 Staffordshire, Denbighshire, South Staffordshire, and Nottingham- 

 shire ; and their Relation to the Productive Series." By Walcot 

 Gibson, Esq., F.G.S. 



(Conimuuicated by permission of the Director of H.M. Geological Survey.) 



The Upper Coal-measures of North Staffordshire are capable of 

 a fourfold subdivision, the groups representing a definite sequence 

 of red and grey strata : — 



4. The Keek Series. Eed aud purple sandstones and marl with occasional seams of 



coal, and bands of entomostracun limestone. 

 3. The Newcastle-under-Lyme Series. Grey sandstones aud shales, with four tliiu 



seams of coal, and at the base an entoraostracan limestone. 

 2. The Etruria Marl Series. Mottled red-and-purple marls and clays, with thin 



green gi-its ; a thin coal occurs L50 yards above the base. 

 1 . Black Band Series. Grey sandstones, marls, and clays ; numerous thin seams of 



coal and Blackband ironstone ; one of many thin bands of limestone is 



constant, 36 to 40 feet above the base. 



Spirorbis- and entomostracan limestones attain a maximum in the 

 Upper Goal - measures, but are not unknown in the productive 

 measures below. Indeed, the two sets of measures are closely allied 

 lithologically, palaaontologically, and stratigraphically in this region. 

 The chief movements are pre-Triassic and post-Carboniferous. 



No attempt has been made to recognize the Black Band Series in 



