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I. Transition Series. 



In Kerry there is a persistent series of transition rocks, having a 

 general direction from east to west, and dipping to the north and 

 south with vertical beds in the axes of the ridges : the strata as they 

 diminish in inclination on each side, form a succession of troughs. 

 The principal rock- masses are composed of grauwacke, slate, and 

 limestone ; but the general series is distinguished, by the author, 

 into simple and compound rocks ; the simple being clay-slate, 

 quartz-rock, hornstone, lydian-stone, and limestone. The com- 

 pound sandstone and conglomerates with bases of clay- slate, quartz, 

 and sandstone ; grauwacke, and grauwacke-slate ; sandstone and 

 sandstone-slate ; greenstone ; and hornstone-porphyry. Roofing- 

 slate, though comparatively rare, is found of an excellent quality in 

 the island of Valentia. 



Organic remains occur more frequently in the limestone of this 

 series than in the slate and grauwacke. In Kenmare these remains 

 consist of a few bivalves, and some crinoidal remains; and these also 

 are most numerous in the Muckruss and Killarney limestones. At 

 the foot of the Slieve-meesh range this limestone includes Asa- 

 phus caudatus, Calymene macrophthalma, and perhaps a third crus- 

 taceous animal, with Orthoceratites, Ellipsolites ovatus, an Am- 

 monite, Euomphalites, Turbinites, Neritites, Melanites, and seve- 

 ral species of Terebratula, Spirifer, and Producta. Other bivalves 

 in this locality are referrible to species figured by Schlotheim, as 

 from transition rocks on the Continent. 



Near Smerwick harbour, similar organic remains are abundant in 

 slate, and fine-grained grauwacke, together with Hysterolites, and 

 many genera of polyparia ; the whole resembling both in mineral 

 and zoological characters the rocks of Tortworth in Gloucestershire, 

 formerly described by the author, as well as those of the Taunus in 

 Nassau, more recently described by Sir Alexander Crichton. Again, 

 the same fossils are found in the limestone of Cork, associated 

 with impressions of vertebra? of fishes; and analogous remains are to 

 be met with also in a portion of the slate of that neighbourhood. 



Transition coal. — All the coal of the province of Munster, except 

 that of the county of Clare, is referrible to one of the earliest periods 

 at which that mineral has been produced ; the true coal overlying 

 the mountain limestone being found in that county alone. At 

 Knockasartnet, near Killarney, and on the north of Tralee, thin an- 

 thracitic beds, inclined at various angles from 70 degrees to vertically, 

 are included in grauwacke and slate. In the county of Cork this old 

 coal is more extensively developed, particularly near Kanturk, ex- 

 tending from the north of the Blackwater to the Allow. The gorges 

 of the latter river, and various other neighbouring defiles, expose 

 clay-slate, grauwacke, shale, and sandstone, in nearly vertical beds, 

 directed from west to east. This transition tract extends to the 

 river Shannon on the north-west. As the systems range from west 

 to east, in a series of parallel, acutely angled troughs, the beds have 

 great diversity of inclination, dipping rapidly either to north or south, 

 and bending to horizontality between the ridges. This coal or 



