408 Scientific Proceedings, Royal Dublin Society. 



summit. These, for the most part, are composed of highly altered 

 rocks that have been suggested to be of Laurentian age ; but, as 

 previously mentioned, are more probably metamorphosed Arenig. 

 In them, towards their south margin, are tracts of ophyte, gene- 

 rally dark olive-green, approaching to black, but some are of 

 lighter colour or variegated or streaked. 



About three miles north-west of Pomeroy, west and south- 

 west of the lake that lies half a mile west of the summit of 

 Oregganconroe, are four distinct patches of ophyte ; while a little 

 to the west, on the hill called Scalp, is a fifth. At Athenree, 

 about a mile and a-half S. S.W. of Scalp, and a mile south-east 

 of Carrickmore or Termon rock, there is also a tract, and another 

 about half a mile W.N.W., of Carrickmore. In the last, the rock, 

 in places, has a decided variegated or streaked colour. Some of 

 these stones have a good appearance, and seem to be qualified 

 to produce a marble. As yet, none of them have been utilized or 

 even tested. 



Waterford. 



In this county the serpentines recorded are only of very small 

 extent. As, however, the rocks of the eastern portion of the 

 county are similar to those of the adjoining counties of Wexford 

 and Wicklow, and as among the latter ophyte only recently has 

 been recorded, it formerly having been included among the 

 pyroxenic rocks, it seems not improbable that here, as in Wicklow 

 and Wexford, there may be small tracts of ophyte still unrecorded. 

 This, however, has still to be examined into. 



Wexford and Wicklow. 



The presence of ophyte was not recorded in these counties 

 until within the last five years, although " serpentine " is mapped 

 on the old geological six-inch maps. This, probably, is due to the 

 fact that, until recently, many geologists classed them with the 

 pyroxenic rocks, of which they are metholotic varieties. They are 

 now known to occur in the following localities : — 



On the north and south slopes of the western spur, extending 

 from Croaghan Kinshella, in the townlands of Gummer, Cummer- 



