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 230 with which the argillaceous rocks in the south slope of the Himalaya represent the English lias,—an agreement which, perhaps, by further researches, may be found not less complete than that presented by the lias of Wurtemburg and Franconia, which can hardly be said even to differ from the argillaceous rocks of the Yorkshire coast. (See Geol. Proceedings, for Murchison's notices of the Banz Series, and Voltz on Belemnites, for proof of the identity of the Wurtemburg and Whitby

Spain, the Balearic Islands, and the Apennines, contain the oolitic system, which also appears in the range of the Atlas.

Physical Geography.—The oolitic tracts of England present a broad band of dry limestone surface, rising westward to elevations of 800 and 1100 feet (in Yorkshire 1485 feet), with escarpments commanding very extensive prospects over the undulating plains of lias and red marl. Even where the valleys are abrupt, as about Stroud and Bath, the scenery, though pleasing, appears tame to one acquainted with the older strata. This arises from the comparative softness and easy destructibility of the rocks; for in some parts of the Swiss Jura the harder limestones appear in mighty precipices. The facility of waste has permitted, on the western border of the districts in England, the production of frequent outlines of the limestones on the clays; as Bredon Hill, which stands up in the vale of Gloucester to attest the powerful effects of ancient water.

The whole tortuous line of oolitic escarpment from the Humber to the Avon may be regarded as the wasting effect of water on the subjacent red marls and lias clays; but what that water, when and how applied, is a problem of general geology, on which we may enlarge hereafter.