KiNAHAN AND Baily — RepoH 0)1 JRocks, 8fC. 491 



hood of the Ballygawley eurite, there is, apparently, a vast thickness 

 of conglomerates. It is probable, however, that the thickness of these 

 is no more than apparent, and that here, as in the similar conglome- 

 rates of Toormakeady, Co. Mayo, the conspicuous structural lines are 

 only lines of oblique lamination. 



The interbedded eurites, like those in S. W. Mayo and N. "W. 

 Galway, have their granitic roots in the older rocks. Thus four miles 

 N. E. of Six-mile-Cross, at the Granagh stream, are rocks in part 

 granite and in part elvan, while south of them is the eurite mentioned 

 in the last section (No. 2), which seems to be on a lower geological 

 horizon than the eurites, &c., of Altmore. Other roots occur in the 

 metamorphic area north and north-west of Six-mile-Cross, and else- 

 where. At the mearing of the counties of Tyrone and Fermanagh a 

 mass of shaly eurite was observed and boulders of limestone ; but 

 time did not allow of that county being fully examined. Mela- 

 phyres, similar to those that occur in the Mayo and Galway Silurians, 

 are found among the rocks of the Fintona district. 



To the S.W. of this area special attention was directed to the con- 

 glomerate of Lisbellaw, which at that village occurs in mass on the 

 Cambro-Silurians. Half a mile to the W.N.W., however, in the rail- 

 way cutting, red sandstones are found close to the Cambro-Silurians, 

 while in the stream at the N.E. end of Lough Eyes, two miles from 

 Lisbellaw, the basal rocks are thin conglomerates, sandstones, and 

 shales. Of the interesting blocks in the conglomerate, Mr. Thomas 

 Plunkett, M.R.I.A., states that he " can find no rocks in JS'.W. Ireland 

 like them, the nearest approach being some of the rocks of West Done- 

 gal." It seems probable that as these inliers are granulite, hornstone, 

 quartzite, and other paroptetic rocks, similar to the " baked rocks" of 

 Cambro-Silurian age in other places in Ireland, that they may be de- 

 rived from a now concealed mass of baked Cambro-Silurians, while 

 the associated inliers of green shale may be the debris of the unal- 

 tered rocks. A characteristic of the red arenaceous rocks of the 

 Topped Mountain district, to the northward of Lisbellaw, is the pre- 

 sence of innumerable inlying pieces of red, purple, and sometimes 

 green shale. If we may judge from what goes on at the present day, 

 these inliers were small pieces of clay rolled over the sand by the 

 wind, and afterwards flattened out ; but where the source of supply 

 was situated it is hard to conjecture. 



Of the "Lower Old Red Sandstone" of the Curlew Mountain district 

 the most eastward exposure is to the S. E. of Drumshambo, on the 

 eastern side of the Shannon. Both types occur here ; those of the 

 "green" series underlying a small thickness of the red; no fossils 

 have been found as yet, although one bed at least looks likely to yield 

 some, if sufficiently searched. It is possible, if not probable, that 

 these rocks are on a much lower geological horizon than those to the 

 west of the Shannon, east and west of Lough Key. The rocks west- 

 ward of Lough Gara seem to be the oldest in the Curlew Mountain 

 district, the basal beds cropping out in the country between Charles- 



E.I.A. PROC, SEK II. VOL. III. — SCIENCE. 2 S 



