﻿Reports and Proceedings. 281 



these are numerous Igneous Eocks. All are described in detail, as 

 well as the character and causes of raetamorphism. Much attention 

 has been given to the Igneous Eocks (a new feature in connexion 

 with the Survey publications) ; and the work is accompanied by 

 three coloured plates of microscopic sections of these rocks. 



The faults and mineral veins are described, and one chapter is 

 devoted to Plumbago or Graphite. Cleavage is the subject of another 

 brief chapter, while the Physical History of each formation is dwelt 

 upon at more length. The Glacial Phenomena of the District, and 

 the Eelation of the Scenery to Geology receive due attention, and 

 the concluding chapter is devoted to the fossils of the Skiddaw 

 Slate. In an Appendix Mr. Etheridge describes some new species 

 of Trilobites from this formation, and one new genus of Annelida, 

 termed Stella-scolites. There is also a useful Appendix containing a 

 list of all works bearing on the geology of the district. 



isEi^oiaTs j^isTjD iPiaoGDBiEnDin^ca-s. 



Geological Society of London. — I. — April 25th, 1877. — Prof. 

 P. Martin Duncan, M.B., F.E.S., President, in the Chair. 



1. ■'' On the Upper Limit of the essentially Marine Beds of the 

 Carboniferous System, and the necessity for the establishment of a 

 ' Middle Carboniferous Group.' " By Prof. E. Hull, F.E.S., F.G.S. 



The author, in this paper, divided the whole of the Carboniferous 

 rocks into successive stages from A to G inclusive, taking the Car- 

 boniferous beds of Lancashire as a type, and showed that these 

 stages could be identified over the whole of the Biitish Isles. It 

 was only recently that their determination had bee a made in 

 Ireland, so that until now the materials had not existed for a 

 complete correlation of the series in the British Islands. The 

 following is an abbreviated statement of the representative stages 

 in descending order : — 

 Essentially Freshioater or Estuarine, with one or two Marine Bands. 



Stage G. — Upper Coal-measures of Lancashire (2000 ft.) and 

 other English coal-fields. Eed Sandstones, etc., of Bothwell and 

 Ayr, in Scotland. (Absent in Ireland.) 



Stage F. — Middle Coal-measures of Lancashire, etc., with prin- 

 cipal coal-seams (3000 ft.). Flat coal series of Scotland. Present 

 in Ireland (Tyrone, Kilkenny). 



Essentially Marine. 



Stage E. — ^' Gannister Beds" (Phillips), with marine shells and 

 thin coals (2000 ft.), in Lancashire. " Pennystone series" of 

 Coalbrook Dale, South Wales, etc. " Slaty black-band " series 

 of Scotland. (Present in Ireland, Kilkenny, Dungannon, Lough 

 Allen Coal-fields.) Also in Belgium, Ehenish Provinces, and 

 Silesia, with numerous marine shells. 



Stage D. — Millstone Grit Series of England and Wales, 3500 ft. 

 in Lancashire ; " Moorstoue Eock " of Scotland : " Flagstone-series " 

 of Carlow and Kilkenny ; Millstone Grit of Fermanagh and Leitrim, 

 with coals and marine shells. 



