476 Mr. Weaver on the Structure of the South of Ireland, Sfc. 



Silurian fossils. The immediate substrata of the Dunloe red 

 conglomerate, sandstone, and red slate are not visible, being 

 unconformahly overlaid on the north by the carboniferous 

 limestone in the western quarter, and by the coal formation 

 in the eastern ; while, on the other hand, the transition series 

 of the Dingle peninsula, just described, are unconformahly 

 overlaid on the east by the old red sandstone of the Slieve 

 Meesh range (Cahircouree of Mr. Griffith); the difference in 

 the aeras of production between the transition series and the 

 carboniferous sei'ies being thus in both cases clearly mai'ked*. 



To the south of the strata of which we have been speaking, 

 there is a band of blackish-grey clayslate, which may deserve 

 Mr. Griffith's attention. It is traversed by the new line of 

 road from Killarney to Kenmare, as it passes up by the line 

 of the Upper Lake, and if duly examined might perhaps be 

 found productive of fossils. This instance may suffice to 

 show that there is no want of repetition of similar beds in 

 a line traversing the series from north to south. In the 

 general succession occur also well-defined greywacke and 

 greywacke slate, terms which being out of favour with some 

 geologists, Mr. Griffith appears to avoid using, although 

 highly distinctive and useful when employed in a legitimate 

 sense. 



Upon the whole, I see no reason to depart from the opinion 

 which I have formerly given, namely, that the limestone of 

 the region of Muckruss extending to Killarney, is a local 

 deposit enveloped and intercalated in the general transition 

 series. And the same view, as to their forming portions of 

 the consecutive series, applies to the other limestone bands 

 in the south of Ireland, whether inclosed in and interstrati- 

 fied with the adjacent rocks, or merely superimposed and 

 interstratified in the form of a trough with the subjacent 

 series. In the valley of Kenmare this latter position appears 

 to be established by the detailed researches of Mr. Griffith, 

 which, I confess, escaped my observation. 



That amonfj the strata in immediate association with the 

 bands of limestone in the south of Ireland, some should be 

 found, whether bearing ihe character of sandstone or clay- 

 slate, containing certain vegetable remains, cannot be held 

 sufficient to invalidate the general view which I have taken ; 

 1st, because such remains are not wholly foreign to a transi- 

 tion country ; and 2nd, because it has been shown that the 

 older stratified rocks of the south of Ireland form one con- 

 secutive series. 



* See my Geological Map of the South of Ireland in Geol. Trans., vol. v., 

 second series. 



