BRITISH ASSOCIATION MEETING. 



511 



About twenty-one feet above the thin mine there is a bed of impure cannel, 

 over which there is a band of large Anthracosia. In the shales below the 

 cannel two species of Anthracosia, much smaller than the overlying ones, are 

 met with. 



The next overlying coal is a four feet, having a roof of strong blue shale, 

 containing an abundance of coal-measure plants, some of which have the Spi- 

 rorbis carbomrius adhering to them. At a distance of seventy-five feet above 

 the last-named coal, we have the Lower Yard Bed, the roof of which contains 

 a band of very large Anthracosia, thought by some geologists to be identical 

 with the Anthrocosia robusta found over the Arley mine in the Wigan district. 

 The outcrop of this mine, together with the overlying band of Anthrocosia, is 

 exposed near to the north entrance of the Towneley tunnel. 



The next ascending coals are the Higher Yard Bed ; the Main Coal, five feet ; 

 Shell Bed, three feet ; and the Kershaw Bed, three feet ; none of which have 

 any fossils in connection with them worthy of special notice. 



Nearly twenty-one feet above the Kershaw Bed, and about thirty feet from 

 the surface, lies the Dog Holes coal, the highest and the thickest of the Burn- 

 ley mines. The roof of this coal, consisting of a light grey sandstone parted 

 by bands of blue shale, whenever laid open, has revealed in the greatest abun 

 dance ferns of the genera Neuropteris, Pecopteris, Sphenopteris, &c, together 

 with both the stems and leaves of Lepidodendron Sternbergii, Catamites, and 

 Stigmaria ficoides, perforating the rock in every direction ; some of the latter 

 having been traced for many yards in a horizontal position, sending out their 

 rootlets at right angles to the main stems to a great distance. Large fossil 

 trees of the genera Sigillaria are also abundant, some of them reaching a dia- 

 meter of several feet. Seven such were found in the limited space occupied 

 by a small cotton mill recently erected in Church-sireet, Burnley, by Mr. 

 Dixon; and others were found in Mill-lane during the construction of a 

 common sewer. The whole of them being in an upright position, thus afforded 

 the best possible evidence that they had grown and flourished on the spot. 



The whole of the overlying rock may be described as an immense fossil 

 forest, occupying the central part of the Burnley coal-field ; the town itself 

 being situate on what was once one of its richest lagoon jungles, replete with 

 the flora of a former geological period. 



ON THE OCCUBILENCE OF GOLD IN MERIONETSHIRE. 



By T. A. Readwin, F.G.S. 



The author confined his observations to an area of about twenty square 

 miles, situate north of the turnpike road leading from Dolgelly to Barmouth, 

 county Merioneth. 



Professor Ramsey has ably described the geology of this district, in a com- 

 munication to the Geological Society of London, 1854 ("On the Geology of 

 the Gold-bearing Districts of Merionethshire.") 



The Dolgelly district is bounded, or nearly so, by the picturesque and tidal 

 river Mawddach, the great Llawllech or Merioneth anticlinal range, and the 

 little river Camlan, to which may be added a continuation of about three miles 

 further norxh-east, at the junction of the Cambrian sandstone, and the Lower 

 Silurian Lingula-flags of the Geological Survey, and included in the survey- 

 maps 75 south-east and 59 north-east. 



In this district are found the Cambrians overlaid by the Lower Silurian Lin- 



