BBITISH ISLES. 21 



the Killamey Mountains near Lough Guitane, at Lough Garagarry, 

 The Devil's Punch Bowl, and Crohane, &c. ; also at Cod's Head and 

 Dursey Island, and on the shores of Lough Kay and Valentia Har- 

 bour. Lower Carboniferous Volcanic Rocks are well shown in the 

 Limerick Basin, and belong to two periods of eruption. Microscopic 

 examination shows them to belong, with few exceptions, to the old 

 augitic lavas, or " melaphyres," the base being triclinic felspar, en- 

 closing crystals of augite, olivine, magnetite, and grains or bands of 

 chlorite. To the same period belong the volcanic rocks of Bantry 

 Bay. To the Tertiary period belong the great sheets of augitic lavas 

 occupying the N.E. of Ireland, extending to the west of Scotland and 

 Inner Hebrides, and referrible to three periods. The earliest eruptions 

 were those of highly silicated lavas, trachytes, rhyolites, and pitch- 

 stones, the old vents of which are found near Hillsborough and also 

 among the hills N.E. of Antrim. These preceded the Miocene basalts, 

 and are probably of Upper Eocene age. Then, after a period of repose, 

 a flow of augitic lavas, basalt, &c. took place, one of the vents being 

 Scrabo Hill, Co. Down. Another cessation then occurred, during 

 which the valuable beds of lithomarge and iron-ore were formed under 

 lacustrine waters. Lagoons also existed ; and beds of lignite were 

 formed. The plants of these are of Miocene age, establishing the co- 

 incidence in time of the basalts with that of Mull and the Hebrides. 

 The third outflow now took place, great sheets of basalt, sometimes 

 400 or 500 feet thick, being poured out. The principal necks of this 

 period may possibly be those of Dunluce and Sleamish ; and this out- 

 burst was accompanied or followed by the protrusion of dykes, cutting 

 through both old and new sheets. All these volcanic operations seem 

 to have been subaerial. The subsequent denudation has been enor- 

 mous. E. T. H. 



Hunter, — . Vertical Section of Carboniferous Strata, West of Scot- 

 land. Part i. 27 pp. 8vo. Carluke. 



A detailed section of 642 separate beds from the New Red to the Old 

 Red Sandstone. Local names are given ; and beds in which fossils have 

 been found are noted. G. A. L. 



Irving, Rev. A. On the Geology of the Nottingham District. Geol. 



Mag. dec. 2, vol. i. pp. 314-319. 

 Has since been published in full in Proc. Geol. Assoc. 1875. 



Jamieson, T. F. On the Last Stage of the Glacial Period in North 

 Britain. Quart. Journ. Geol. Soc. vol. xxx. pp. 31 7-337 (woodcuts). 



There are three well-defined stages in the history of the Glacijil 

 Period of Scotland: — 1. the great glaciation by land-ice; 2. sub- 

 mergence and the formation of glacial marine beds ; 3. the period of 

 tlie later glaciers. It is chiefly with the last that this paper is con~ 

 cerned. Its object is to show that the development of ice and snow 

 during the third period must have been far greater than is generally 

 supposed. Local glaciers will not suffice to explain the facts ; a great 

 ice-sheet must have spread over nearly the whole of Scotland and 



