Geological Society. 87 



PROCEEDINGS OE LEARNED SOCIETIES. 

 GEOLOGICAL SOCIETY. 



November 4th, 1908.— Prof. W. J. Sollas, LL.D., Sc.D., F.R.S., 



President, in the Chair. 



The following communication was read : — 



' On the Fossil Plants of the Waldershare and Fredville Series of 

 the Kent Coalfield.' By E. A. Newell Arber, M.A., F.L.S., F.G.S. 



At the boring at Shakespeare Cliff, Dover, Coal-ileasures were 

 reached in 1890 at a depth of 1100 feet, and subsequently penetrated 

 to a depth of about 2270 feet. Thirteen seams of coal, varying in 

 thickness from 1 to 4 feet, were pierced. Coal-Measures were struck 

 at 1394 feet at the boring in Waldershare Park, and pierced for 

 1260 feet more. Five seams of coal, varying from 1 foot 4 inches to 

 5 feet 2 inches iu thickness, weie struck. The boring near Fredville 

 Park reached Coal-Measures at 1363 feet, pierced three seams of 

 coal, and was continued to a depth of 1813 feet. The specimens 

 of plants collected from the Waldershare and Fredville borings are 

 dealt with in detail, and compared with plants found at Dover and 

 in other localities in Britain and abroad. The more abundant 

 and characteristic species are common to Waldershare and Fred- 

 ville, and lead to the conclusion that the beds belong to the 

 same horizon. The majority of species tabulated are either 

 confined to the Upper Coal- Measures and the Transition Series 

 below, or are Middle and Lower Coal-Measure forms which are 

 known to occur in the Transition Series. Indeed, all but two 

 plants have been recorded from the last horizon. Thus the beds 

 are the homotaxial equivalents of the Newcastle, Etruria, and 

 Bbick-Band horizons of North Staffordshire, the Hamstead Beds 

 below 1233 feet in South Staffordshire, the Coed-yr-allt Beds and 

 Ruabou Marls of Denbighshire, the Ardwick Series and Beds above 

 the Bradford Four-Foot Coal in South Lancashire, the Lower Pennant 

 Grit of South Wales, and the New Rock and Yobster Series of Som- 

 erset. The data with regard to Dover are too scanty for certainty, 

 but they seem to indicate approximately the same horizon as the two 

 other Kentish localities. The majority of species are also common 

 to the highest zone, or the ' Charbons Gras,' in the Pas de Calais. 

 The flora of these rocks, and of those on the same tectonic line, 

 belongs to the lower of the two great Continental zones of the 

 Upper Carboniferous — the Westphalian ; and the higher zone, 

 the Stephanian, is unrepresented in the Mendip-Artois series of 

 basins. But, as this axis is followed from east to west, it appears 

 that continuously higher horizons are met with. 



