Page:Quarterly Journal of the Geological Society of London, vol. 35.djvu/840

700 identified them with the rocks which form the Reeks and Glengariff ranges.

1838. Mr. Thomas Weaver, in a memoir "On the Geological Relations of the South of Ireland", described the rocks forming the mountains of Cork and Kerry under the old name of "Greywacke and slate of the Transition series."

1839. Sir Richard Griffith, in presenting his Geological map of Ireland to the Geological Society of Dublin, also read a paper on the principle of colouring adopted in the above map, and on the geological structure of the South of Ireland, in which he refers to the discovery of numerous Silurian fossils in beds in the Dingle promontory, notices the discordant superposition of the Old Red Sandstone on the clayslate of Dingle, and expresses the opinion that "eventually the greater part, if not the whole, of the schistose rocks of the counties of Cork and Kerry" will prove to be Silurian.

1845. Mr. C. W. Hamilton, in a paper "On the Rocks in the neighbourhood of Killarney", contended, in opposition to Sir R. Griffith, that those of the Killarney and Dingle mountains are not Silurian but of Devonian age. To this paper Sir Richard replied in the same year ; and in 1855, in the second edition of his geological map of Ireland, the beds forming the western portion of the Dingle promontory, and the mountainous tracts of Kerry and Cork, are coloured and lettered as "Silurian," and described as "chloritic or brownish-grey quartzite or agglomerate, occasionally alternating with green and purple slate."

1856–7. Prof. Haughton, Prof. J. Beete Jukes, and Mr. Salter discussed the classification of the Devonian and Carboniferous rocks, the latter authors contending for the collocation of the Yellow Sandstone with Knorria dichotoma, Anodon Jukesii, &c. with the upper part of the Old Red Sandstone. In 1857, also, Mr. G. V. Du Noyer gave a minute description of the rocks of the Killarney district, and assumed the purple and green slates and grits to be of Lower Old Red Sandstone age.

1858. Sir Richard Griffith again took up the question in his "Notes on the Stratigraphical Relations of the Sedimentary Rocks of the South of Ireland", in which he indicates that the base of the Old Red Sandstone may be recognized in the Dingle promontory with the same unconformity to the underlying rocks as in other districts examined, but that the beds with Upper Silurian fossils at the extreme west of the promontory pass up directly into the "Glengariff grits;" and, considering the discordancy between these and the Old Red Sandstone, he had no longer any hesitation in regarding the Glengariff beds as belonging to the Silurian system. These opinions are supported by Mr. J. Kelly in a paper "On the Graywacke Rocks of Ireland as compared with those of England".