Page:A Treatise on Geology, volume 1.djvu/222

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A TREATISE ON GEOLOGY.
CHAP. VI.

near Malvern, are poor representatives of the voltziæ, calamities, and ferns of the German trias: nor could we, from the little bivalve which occurs in the Keuper of Salop (Posidonomya minuta), conjecture the variety of testacea which is yielded by the coeval strata of Sulz les Bains. Our fish and reptile remains are more numerous. The latter in particular (Labyrinthodon), known by footprints in Cheshire and Dumfriesshire, and by bones and teeth from Warwickshire, are extremely interesting.

The German trias yields a sufficiently large series to remove all doubt as to the truly mesozoic character of the deposits.

Geographical Extent.—Slight traces of new red sandstone occur on the western coasts and islands of Scotland: some considerable area is occupied by it in the country between Coleraine and Dungannon, about Belfast, and on the coast of Antrim. The Solway Firth is in red marls and sandstones, and all the rivers which enter it from the Scottish frontier flow through the same; the plain of Carlisle; the western coasts, from Whitehaven to Furness; the peat mosses of South Lancashire, and the Vale of Clwydd are in the red formation. The river Tees enters the sea in gypseous red marls and sandstones; so does the river Exe in Devonshire; and between these two points is an almost uninterrupted line of the same strata, ranging by York, Nottingham, Warwick, Worcester, Aust Passage, Taunton, and Honiton. It expands westward from Nottingham to Derby, Manchester, Liverpool, and Shrewsbury,—thus occupying an enormous area in the centre of England, partially broken by the upheaved coal measures of Leicestershire, Warwickshire, and Staffordshire. Small detached portions appear in Monmouthshire, Glamorganshire, and Devonshire.

On the continent of Europe, still larger spaces are covered by the saliferous system than in England. A small continuation of the Devonshire red rocks appears