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In France and England the muschelkalk is absent. Rock salt and brine springs occur in England and France only in the Keuper series: in Germany both in this and in the muschelkalk. Gypsum usually accompanies the marls which yield salt, but is also of more extensive occurrence.

In England the most complete section is probably that furnished by the beautiful and fertile vale of Severn, where every bed between the lias and the Palæozoic rocks of the Malvern and Abberley hills is easily traceable, in a thickness of 400 to 500 yards. The lowest of these beds, trappoid conglomerate, is probably of Palæozoic age,—a representation of some part of the Permian system. The series in general terms stands thus,—

Farther south, the lower sandstones nearly vanish (in Somersetshire), but the marls receive a peculiar (local) calcareous conglomerate (millstone), to which probably the reptiles of Durdham Down may be referred.

Farther north, the series is continued and very widely expanded the marly upper portions admitting rock salt in Worcestershire and Cheshire : the sandy