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GRANITE. 29 YI. Medium-grained granite, from Blackstairs Mountain, Co. Wexford. Haughton, supra cit. Contains no oligoclase. VII. Medium-grained granite, from Doocharry Bridge, Co. Donegal; consisting of flesh-coloured orthoclase, grey oligoclase, quartz, and a little black mica. Haughton, ibid. vol. xviii. p. 402 (1863). VIII. Granite from Baveno, Italy; containing flesh-coloured orthoclase, white oligoclase, quartz, and dark green mica. Bunsen, Mittheilung an Both, Gesteinsanalysen, 1862. IX. Granitite from Warmbrunn in Silesia; red orthoclase, yel lowish oligoclase, quartz, and a little biotite. Ibul. X. Granite from Meineckenberg in the Harz ; prevalent bright greenish oligoclase, a little orthoclase, much mica and little quartz. Fuchs, N. Jahrb. fur Mineralogie, &c., 1862. XI. Granite from the Mourne Mountains; containing quartz, orthoclase, albite, and green mica. Haughton, Quart. Journ. Geol. Soc. vol. xii. 192. XII. Protogine granite, from the northern flank of Mont Blanc. Schonfeld and Roscoe, quoted by Zirkel, Petrographie, vol. i. 492. XIII. Egyptian granite (or ‘syenite’), from a fragment of an antique in the collection of the Louvre, Paris, by Professor Delesse. Journ. Geol. Soc. Lond. vol. vii. 7. Varieties of Granite and Examples. The varieties caused by variations in the number and proportions of the constituents, their colours, and the presence of accidental minerals, are almost endless; but I shall select a few of the most remarkable and more useful examples for description. In some cases, as in the Western Alps, talc replaces the mica, in which case the rock receives the name of ‘ protogine ’ granite ; 1 1 Some doubt has been thrown, on the authority of Dr. Haughton, on the accuracy of this generally received view. See Jukes’ Manual of Geology, 3rd edit. 124 (1872).