Page:A Treatise on Geology, volume 1.djvu/245

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CHAP. VI.
MESOZOIC STRATA.
229

Caen, Narbonne. Mezières. Can. Poitiers. Chamberi. Bayonne. Nice. and running south to near Lyons. From near Poitiers branches pass off westward to La Rochelle, and south-eastward to the Cevennes. The north flank of the Pyrenees has a belt of oolitic rocks. Another range passes from near Narbonne due N. E. to Savoy, where it bifurcates; one branch forming the French and Swiss Jura, which, crossing the Rhine above Basle, continues north of the Danube to Ratisbon, and thence turns north to the Mayne at Banz. The other branch keeps the south side of the Rhone, to the Vallais, and thence forward to Vienna forms part of the great chain of the Alps, but is so altered in aspect from ordinary "Jura kalk" as to have been for a long time considered as quite of a different age. The limestone, north of the Carpathians about Krakow, may be looked upon as of the same age.

The south side of the Alps is in like manner bordered by a similar range of the Jura kalk, from the Lago Maggiore, by Lago di Guarda, Belluno, and Lay bach, where it expands greatly, and sends off ridges through Illyria, Dalmatia, Albania, and Greece.

Throughout the greater part of this range, except in France, the minute distinctions of the English formations vanish. In the Swiss and German Jura, and the Alpine borders, the oolitic rocks, though connected with the strata of Normandy, vary greatly from that type, so that in some districts hardly any member but the lias can be perfectly discriminated from the general oolitic mass. This renders very singular the perfect exactness