344 MAPS AND SECTIONS. 



other places. At Carnmoney Hill a supposed volcanic neck of Miocene 

 age is marked. This is the first hill-shaded map published by the 

 Geological Survey of Ireland. 



Sheet 76. By Richakd Symes and S. B. "Wilkinson. Contains 

 parts of the counties Mayo and Roscommon (Ballaghadereen, Kilkelly, 

 and Kiltamagh). The formations represented are : — Aqueous, Sfc, 

 Bog and Alluvium, Drift, Carboniferous Limestone, L. Carboniferous 

 Sandstone, Old Red Sandstone, "Wenlock, IT. Llandovery. Ir/neous, Ba- 

 salt (dyke) Quartziferous Porphyry, Pelstone, Melaphyre, or Diabase, 

 Pelspathic Ash, which occur in dykes or masses. The north-east and 

 north centre are occupied by the older Palaeozoic and' the Igneous 

 rocks, and the remainder of the sheet by the Carboniferous beds. Bog 

 and Alluvium occupy a large area in detached patches. Glacial 

 striations are scarce. 



Sheet 80. By "W. B. Leonaed. Contains part of Cavan and Meath, 

 with a small portion of Monaghan (Ballyjamesduff, Bailieborough, 

 Kingscourt, Virginia, Moynalty, Oldcourt and Lough Ramor). The 

 formations shown are Bog, Alluvium, Drift, Yoredale Beds, U. Car- 

 boniferous Limestone, Calp Limestone, L, Limestone, with grits, L. ' 

 Silurian (Llandeilo and Bala Beds). The greater part of the area is 

 occupied by Silurian rocks. The Carboniferous beds show in two patches 

 at the south-east and south-west, with a thin strip on the east. The 

 lowest ground occurs to the south. Glacial markings are shown in 

 several places. 



Sheet 83. By G. H. Kinahan, R. G. Symes, J. L. Waeeen, S. B. 

 Wile:inson, and H. Leonaed. Contains two narrow strips of ground 

 extending north and west from the mouth of Killary Harbour on the 

 west coast of Galway and Mayo, and also several islands in the Atlan- 

 tic. The following formations are shown — Bog and Alluvium, Blown 

 Sands, Drift, U. and L. Silurian (Salrock beds, Mweelrea beds), in- 

 cluding Schist, Gneiss, Schistose limestone. Quartz-schist and Quart- 

 zite, relstone-porj)hyry, Dolerite (Melaphyre), Diorite, Diabase, 

 Hornblende-rock, Serpentine or Steatite. . The geology is much com- 

 plicated, and the rocks greatly faulted. ; Copper and Iron Pyrites de- 

 posits are indicated, also glacial markings. 



Sheet 84. By G. H. Kinahan, R. G. Symes, J. L. Waeeen, S. B. 

 Wilkinson, J. Nolan, and H. Leonaed. Includes the parts of Mayo 

 and Galway to the east of the last, and comprises the country around 

 Killary Harbour, Doo Lough and part of the western shore of Lough- 

 Mask, &c. The following formations are shown — Peat Bog, Alluv- 

 ium, Raised Beaches, Drift, Carboniferous Limestone, Carboniferous 

 Sandstone, U. Silurian (Salrock beds, ? Ludlow ; Mweelrea beds 

 ? Wenlock, U. Llandovery), L. Silurian, (Doolough beds. Mica-schist, 

 Hornblende-schist, Quartzite, and Dolomite), Serpentine after Dolomite, 

 Serpentine, Dolerite or Melaphyre, and Diabase, Pelstones, intrusive 

 and interbedded, and Pelstone-porphyry, Quartziferous porphyry 

 (Elvanite), Pelspathic Ash, Diorite, Syenite, Hornblende-rock, Granite 



