GEOLOGICAL SOCIETY OF DUBLIN. 1 7 



The ballot having been opened, the following were elected as Ordi- 

 nary Members : — W. J. Cooper, A.B., and "W. R. Reynall, Trin. Coll. 



Capt. M'Clintock, R.N., was proposed by Mr. E. Percival Wright for 

 election as an Honorary Member. 



GEOLOGICAL SOCIETY OE DUBLIN. 



WEDNESDAY EVENING, NOVEMBER 12, 1856. 



The first meeting of the Society for the Session 1856-7 was held in 

 35, Trinity College, on the evening of the 12th November, 



Gilbeet Sandebs, Esq., in the Chair. 



The Secretary read the Minntes of the last meeting, which were 

 passed; and the following Paper was read by Robebt H. Scott, Esq., 

 C. E. :— 



ON THE CAEBONIFEEOIIS BEDS OE KILLYBEGS, CO. DONEGAL. 



Having had occasion this summer to make a geological section, I, 

 in company with a fellow-student, Mr. J. A. Russell, selected Killy- 

 begs as a locality suitable for the purpose. The strata there are Silu- 

 rian, mainly converted into mica slate, with sandstone and carbonife- 

 rous shale appearing in two districts. One of these, which I shall first 

 describe, is the N. W. boundary of the central carboniferous basin of 

 Ireland. 



In the Eox's Glen, the bed of a stream which flows into Inver 

 Bay, near St. John's Point, we came on black, shaly limestone, con- 

 taining a great profusion of fossils. Here we found encrinitic stems, 

 Atrypa fallax, Spirifer glaber, and Orthis filiaria, with several others. 

 These beds of shale, with some of sandstone interstratified with them, 

 occur along the whole of St. John's Point, as far as we went, which 

 was only to Ballyderlan. In Mr. Griffith's map the whole Point is of 

 the same colour, excepting a small belt at the extreme end, where the 

 lower limestone appears. This we were unable to verify, as the distance 

 by land was very great, and the weather did not suit for going there by 

 sea. Along the shore the most remarkable fossils were, a very large 

 Orthis, which I am told is 0. papilionacea, and Lithostration basalti- 

 forme. Plants have also been discovered in this shale. 



We then crossed St. John's Point to a place near Riggagh Back, 

 where we found the same shales as at the other side. At the point of 

 Riggagh there is a small fault, very well marked. About 200 yards to 

 the west of this, we find the junction of the sandstone and shale, which 

 are perfectly conformable. When we passed M'Swyne's Castle we 

 began to find traces of plants in great abundance in this sandstone. At 

 one spot, about fifty yards east of a brook which comes down from 

 Spamount, we came on a lenticular mass of shaly limestone, similar to 



VOL. IV. D 



