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XXVI. 



THE OCCUREENCE OF DEWALQUEA IN THE COAL-BOKE AT 



WASHING BAY. 



By T. JOHNSON, D.Sc, E.L.S., 

 Professor of Botany, Eoyal College of Science for Ireland ; 



AND 



JANE G. GILMORE, B.SC 

 [Plates XI, XII.] 



Read May 24. Published August 29, 1921. 



In 1918 a boring to test the position of the concealed coalfield was begun by 

 the Ministry of Munitions at Washing Bay, at the south-west corner of Lough 

 Neagh. Owing to the unexpectedly enormous thickness of the beds of clay 

 and basalt (1,500 feet instead of 250 feet estimated), the operations have been 

 abandoned. The core has been placed in charge of the Geological Survey. 

 Early in 1919 Mr. W. B. Wright, f.g.s., brought one of us pieces of the core 

 containing plant remains for identification. For the past two years all 

 available time has been devoted to the investigation of these remains, and 

 many interesting results have been obtained. 



We are indebted to Professor G. A. J. Cole, f.r.s.. Director of the 

 Geological Survey, for permission to examine the core, and to Mr. Wright 

 for the following observations on the geological features of the district: — 



" The boring put down by the Ministry of Munitions in the years 1918 and 

 1919 in search of the concealed coalfield supposed to exist beneath the Lough 

 Neagh basin has yielded the first reliable evidence regarding the geological 

 age of the Lough Neagh beds. The site selected was at Washing Bay, about 

 four miles east of Coalisland, Co. Tyrone. The bore entered the Lough 

 Neagh beds, beneath the glacial drift, at a depth of 48 feet, and reached the 

 base of these beds at 1,196 feet 2 inches. The basal beds of the Lough Neagh 

 series rested on about 70 feet of lithomarge produced by the decomposition 

 of the Upper Basaltic lavas of Co. Antrim, which are well represented 

 below. The series is, therefore, distintly post-basaltic in age, and is to be 



' Miss Gilmore's help was rendered possible by a grant from the Department of 

 Industrial and Scientific Research. 



