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 vations, more or less perfect, confirm this, from the south-western parts of England, northward to the shores of the Tees, all on the direct outcrop between the common Lower Lias and the recognized New Red Marl. Two outliers of Rhaetic beds, formerly called Lower Lias, also appear at Bagots Park and near Newborough, north-west of Burton-on-Trent ; and I do not doubt that the same strata would be found at the base of the outlier of Lias near Whitchurch, in Shropshire, if the rocks of that country were not so much obscured by glacial drift. In Cumberland, round Carlisle, at the mouth of the Yale of Eden, a great tract of Permian strata is directly overlain by Keuper Marls, which are succeeded by Lower Lias, though as yet no Rhaetic beds have been noted in that area, which is also deeply covered by glacial debris and other superficial deposits. In fact, wherever the New Red Marl goes, the Lias follows in apparent conformity ; and wherever the examination has been complete, the Rhaetic beds are found between them, while the Bunter beds, which, were the series complete, would lie beneath the Marl, are often absent, in which case the Marl rests on Permian or any other strata of older date. The Liassic and Rhaetic beds, therefore, appear to act in conformity with the New Red Marl, and in connexion with it ; while the last seems to have in England less immediate stratigraphical relation to the New Red Sandstone — a fact possibly connected with the absence of the Muschelkalk in Britain.

Having reached this point of the argument, it is time to consider the palaeontological part of the question, in relation to the probable physical geography of the time.

In Stoppani's descriptions of the Upper -Trias fossils of Esino * he gives descriptions and figures of a magnificent suite of fossils from beds which, according to his classification, ought to be the general equivalents of our New Red Marl. Only one of these species, Anatina proecursor, passes into his infra-Lias or Avicula-contorta zone. The Lower St.-Cassian and Hallstatt beds, on the opposite sides of the Tyrolese Alps, are believed by Hauer and Suess to be the general equivalents of the Keuper strata of Germany, France, and England, and, of course, of the beds of Esino. They number from 600 to 800 species of fossils.

In Stoppani's work on the infra-Lias and Avicula-contorta zone† of Lombardy, descriptions and figures of about 75 genera and 200 species are given, consisting principally of Mollusca, with a few Echinodermata, Sponges, &c. The fossils are very nearly quite distinct from those of the upper half of his infra-Lias beds, and of our English Lower Lias generally. The thickness of the strata described, the variety and number of the Mollusca and other forms, together with the luxuriant development and proportions of the individual shells, point to the existence in that area, in the south and east of Europe, and elsewhere of a broad open ocean, fitted for the habitation of a large and flourishing fauna — very different in these respects from the development of the British Rhaetic beds, whether we regard their thickness or the fossils they contain.


 * Milan, 1858-60.

† Milan, 1860-65.