1863.] SALTEE UPPER OLD RED SANDSTONE. 487 



uppermost part of the Old Red, as they do in the sections just quoted. 

 This is perhaps the nearest approach to the North Devon type that 

 any of the sections on the parallel of the Bristol Channel present. 



These light-grey sandstones and the intervening grey and green- 

 ish shales should be well searched. They are sure to contain the 

 characteristic Knorria dichotoma ; for this (or analogous Plants) was 

 found by Earl Ducie in the Tortworth grits. And it would be a 

 great corroboration of this view if some beds of the Avicula Damno- 

 niensis could be found among them, as in the "West Pembroke section. 



§ 5. South Ireland. 



While we wait for a memoir on the Irish Upper Devonians, I 

 cannot do better than give a short abstract of the paper by Mr. J. 

 Beete Jukes and myself, published in the ' Journal of the Geological 

 Society of Dublin,' 1855, vol. vii. p. 63. 



First, we found it impossible to separate the so-called Yellow 

 Sandstone of the South of Ireland from the Old B>ed, for the good 

 and sufficient reason that it is, as in all the other sections, the upper 

 part of that formation itself, losing its colour preparatory to the in- 

 troduction of the Carboniferous series. [The Yellow Sandstone of 

 the North of Ireland is a different thing ; as in Scotland it is there 

 • the base of the Carboniferous Limestone, and contains Carboniferous 

 fossils only.] Both in the Yellow Sandstone and the red and green 

 beds below we found the Knorria and its roots (Filicites dichotoma, 

 Haughton). In more productive beds in Kilkenny and near Cork 

 Prof. E. Forbes had already found the Anodonl Jukesii, which is 

 probably a Modiola. Stigmaria and Lepidodendron occurred here, 

 but no decided traces of Sigillaria, nor do I believe there are any 

 instances of this genus occurring below the lowest Carboniferous 

 beds. 



Next, the Carboniferous Slate, which overlies the Yellow Sandstone, 

 is very thin towards the east — that is, in Kilkenny, Waterford, and 

 Wexford (the fine section at the Hook, Wexford, is the best worth 

 study) ; but towards the west it thickens out, and from Cork to Bantry 

 is interstratified at its base with grits, which form, near Glengariff, a 

 group 3000 feet thick, and which were termed by us, as they had 

 been previously by Mr. Jukes and the Irish Survey, " Coomhola 

 Grits." 



If a line be drawn from Kenmare through Macroom and Cork, 

 thence south of Youghal to the Bristol Channel, it will coincide with 

 the boundary between the northern or Herefordshire type of the Old 

 Bed Sandstone and Carboniferous Shale, without the intervention of 

 the Coomhola Grits, and the southern or Devonian type as seen at 

 Bantry, Kinsale, and all through Devonshire. It will define also 

 the northern limit of the " Coomhola Grits." And, lastly, it is the 

 boundary -line between the coarse shallow-water deposits of the Old 

 Bed Sandstone, with pebble-beds and Plants, and the more open-sea 

 Devonian deposits, of thicker mass, finer grain, and lighter colour, 

 full of marine Shells and Corals. The boundary is not an arbitrary 

 one, but appears to have been a line of coast, or of shallow water, 



