1866.] JUKES — OLD RED SANDSTONE AND DEVONIAN. 343 



according to Mr. Baily's determinations and Mr. Davidson's confir- 

 mation of them, to Athyris Royssii or A. concentrica, Chonetes Hard- 

 rensis, Gyrtina heteroclita?, Producta scahricula, P. semireticulata, 

 Hhynchonella pleurodon, Streptorhynchus crenistria, Spirifera lami- 

 nosa, S. striata S. Yerneuillii (disjuncta), and Spiriferina cristata, 

 var. oetoplicata. 



These are especially numerous at Eeenydonegan point, which is 

 made of about the highest beds of the district, where Phillipsia 

 pustulata was to be got in great abundance, and where, in addition 

 to the above-enumerated species, the following were also procured: — 



Alveolites depressa, Chmtetes tumidus, Cyathophyllum (^Petraia) 

 celticum, Fenestella antiqua, Glauconome pluma, Polypora laam, 

 Pullastra histriata, Acrocidia vetusta, Bellerophon subglobatus, and 

 Cyathocrinus variabilis. 



Although the highest in the district now, and 5000 or 6000 feet, 

 at least, above the top of the Old Red Sandstone, it must be recol- 

 lected that we have no proof of these being originally the highest 

 beds of the Carboniferous slate. 



11. The Berehaven Promontory and that of Iveragh and DunJcerron. 

 — We can penetrate in many directions to a depth of many thousand 

 feet into the Old Red Sandstone by means of the numerous glens and 

 ravines in the Glengariff country and throughout the mountainous 

 ground between the valleys of Bantry and Kenmare, or in that between 

 Kenmare and Dingle Bay. In some of these deep recesses, which cut 

 directly across highly inclined beds dipping steadily in one direction for 

 a mile or two at a time, we must come down to beds which are 8000 

 or 10,000 feet below the base of the Carboniferous Slate. In no one 

 instance, however, either there or elsewhere throughout Ireland, did 

 we find any dark-grey slate or any marine organic remains in or 

 below the Old Red Sandstone, until we came down to Silurian rocks 

 and fossils. The prevailing colours of the rocks are red of different 

 tints, alternating with different shades of green. Massive sets of' 

 grits (of a kind called by us Glengariff Grits) and thick bands of 

 slate occur of both these hues ; but no change, either lithological, 

 palseontological, or stratigraphical, which would enable us to draw a 

 lower boundary to the Old Red Sandstone, and say that we had got 

 into any other formation lying below it, is to be found south of 

 Dingle Bay. 



Sir R. I. Griffith does indeed draw a boundary in the middle of 

 these red rocks, and considers their upper part only to be Old Red 

 Sandstone, and the lower to be Uppermost Silurian. I believe, 

 however, that this has been done in order to make the divisions south 

 of Dingle Bay analogous to those in the promontory immediately to 

 the north of it. We were unable to discover any characters which 

 would enable us independently to make such a subdivision to the 

 south of that Bay. That the upper portion, at least, of this great 

 mass is really Old Red Sandstone is beyond a doubt, since it is 

 physically continuous with those masses in the eastern part of Cork, 

 and in the counties of Waterford and Wexford, to which no English 

 geologist could refuse that name. 



