Reports and Proceedings — Geological Society of London. 279 



the encrustations upon recent fossil shells. The characters of the 

 massive older gypsum and rock-salt deposits are described, together 

 with the distribution and lithological changes in the beds when traced 

 across the area by means of borings and outcrops. The origin of the 

 gypsum series is shown to be connected with inland salt-lake conditions, 

 and evidence is presented which suggests that these conditions were 

 contemporaneous with the Oligocene continental period in Egypt, and 

 with the formation of the well - known beds of the Fayimi in the 

 Western Desert. A sketch-map showing, for the first time, the 

 geology of the island situated in the mouth of the Gulf of Suez 

 accompanies the paper. 



3. " Faunal Horizons in the Bristol Coal-field." By Herbert Bolton, 

 F.B.S.E., F.G.S., Curator of the Bristol Natural History Museum. 



The author has been engaged for three years in the examination of 

 the Coal-measures of the Bristol Coal-field, and has determined the 

 existence of faunal horizons at the collieries of South Liberty, Easton, 

 Hanham, Speedwell Deep, and Coalpit Heath in the Bristol and 

 Gloucestershire area, and at Ludlows, Middle Pit, Tyning, Wellsway, 

 Writhlington, Eoxcote, Dunkerton, Newbury, and Mackintosh 

 collieries in the Badstock area. A measured section of 760 feet 

 between the Ash ton Great Vein and the Bedminster Great Yein at the 

 South Liberty Colliery, Bristol, has been examined in detail, and four 

 faunal horizons discovered. These horizons occur at 134, 284, 286, 

 and 637 feet respectively below the Bedminster Great Vein. In every 

 case the fauna was marine in character, and the author's work shows 

 that the Ashton and Bedminster Series of Bristol, the Coalpit Heath 

 and Parkfield Series of the northern part of the coal-field, and the 

 Vobster Series of Badstock are all characterized by a fauna agreeing 

 Avith the typical fauna of the Lower Coal-measures of the coal-fields of 

 the Midlands and of Lancashire and Yorkshire. 



Species of Carlonicola are rare, while the Cephalopod and fish fauna 

 is poor. The Second or Farrington Series of the Upper Coal-measures 

 has yielded Lingida mytiloides, several species of Ostracods, four species 

 of Anthracomya, and scales of Strepsodus sauroides. Ccelacanthus 

 elegans has been found in the First or Upper Badstock Series. The 

 presence of marine phases in the Bristol Coal-field is confirmatory of 

 the evidence obtained by Mr. W. H. Dyson in the Yorkshire Coal-field, 

 where an extensive fauna has been found in four horizons above the 

 Barnsley Coal. 



In the Bristol, as in the Yorkshire Coal-field, the marine fauna 

 undergoes no marked change in its upward range, specific identity 

 being retained in the uppermost horizons, while new species are rare. 



Insect-wings referred to the genus Genentomum have been found 

 at one horizon in the South Liberty Colliery, Bristol, 637 feet below 

 the Bedminster Great Vein ; while the rare Phyllopod, Lectio, leidyii, 

 var. salteriana, hitherto only known from the Lower Carboniferous 

 of Fifeshire, was found in great abundance in the roof-shales over 

 the High Vein of the Parkfield Series at Coalpit Heath Colliery. 

 Frequently the specimens occurred in dense clusters, the latter being 

 distributed over the surface ' of the slabs of shale. The smallest are 

 not more than 2 mm. in length, the largest reaching 8 mm. ; hundreds 



