Rejjovts and Proceedings — Geological Society of London. 281 



The rocks in the area surveyed are roughly divided into four 

 groups, viz. : — 



I. Granite-gneiss and syenite, which apparently represent the 

 oldest series upon which the others rest. 



II. Gneiss, sometimes highly quarfczose and garnetiferous, certain 

 portions passing upward into limestones. 



III. Amphibolites with schists, sometimes micaceous, sometimes 

 chloritic, hornblendic or dolomitic, with altered slates and true 

 conglomerates and limestones. 



IV. Granites and diorites, some of which are clearly intrusive and 

 newer than the rocks which they penetrate. 



A full description of these rocks, geological and topographical, is 

 given under the headings " Underlying granite-gneiss series " and 

 " Newer Limestone, schist and gneiss series." 



The succeeding sections of the report refer chiefly to the economic 

 minerals found in the area surveyed. The most important of these 

 are iron, gold, silver, galena, nickel, mica, apatite, graphite, corundum, 

 and felspar, besides other economic products, including building 

 stones, brick clays, shell-marl, lime, and peat. 



A short account of the glacial geology with a list of strige is 

 supplied, and an appendix contains preliminary lists of fossils by 

 Dr. H. M. Ami, with some interesting notes on the fauna. 



The coloured map (compiled by Mr. Joseph Keele) which 

 accompanies the report, is drawn to a scale of four miles to the inch 

 and has copious geological notes in the margin. A. H. F. 



I^:K!:F'OI^Ts j^istid :F'I^ocE]E;3DII^^a-s- 



Geologioal Society of London. 



L— April 4th, 1906.— E. S. Herries, M.A., Vice-President, in the 

 Chaix'. The following communications were read : — 



1. " On a Case of Unconformity and Thrust in the Coal-measures 

 of Northumberland." By Professor G. A. L. Lebour, M.A., M.Sc, 

 F.G.S., and J. A. Smythe, M.Sc, Ph.D. 



The sections described occur on the coast north of the Tyne, near 

 Whitley Sands, between Table Eocks and Briar Dene Burn. The 

 base of the " Table Eocks Sandstone " is found to rest unconforn;ably 

 upon a series of alternating shales and sandstones, among which 

 is a well-marked band of clay-ironstone crowded with Carbonicola 

 acuta, one of those ' mussel bands ' which are found to be perhaps 

 the most remarkably persistent strata in the North of England 

 Carboniferous rocks. According to the correlation of the Geological 

 Survey, this particular band is the one that is well known as 



