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Show 214 MIOCENE PERIOD. [Ch. XV. and concretionary limestone of a yellowish white colour : it is finely exposed in the escarpments of Wildon, and in the hills of Ehrenhausen, on the right bank of the Mur *· This coralline limestone is not less than 400 feet thick at Wildon, and exceeds, therefore, some of the most considerable of our secondary groups in England, as, for e~ample, the ' Coral Ragt.' Beds of sandstone, sand, and shale, and calcareous marls, are associated with the above-mentioned limestone. The third group, which occurs at a still · greater distance from the mountains, is composed of sandstone and marl, and of beds of limestone, exhibiting here and there a perfectly oolitic structure. In this system fossil shells are numerous. It is by no means clear that the coralline limestones of the second group, are posterior in origin to all the beds of the first division; they may possibly have been formed at some distance from land, while the head of the gulf . was becoming filled up with enormous deposits of grave], sand, and mud, which may, in that quarter, have rendered the waters too turbid for the fullest development of testaceous and coralline animals. In regard to the age of the formations above described, we may observe that the middle group, both in the basins of Styria and Vienna, belongs indisputably to the Miocene period, for the species of shells are the same as those of the Loire, Gironde, and other contemporary basins before noticed. Whether the lowest and uppermost systems are referrible to the same, or to distinct tertiary epochs, is the only question. We cannot doubt that the accumulation of so vast a succession of beds required an immense lapse of ages, and we are prepared to find some difference in the species characterizing the different members of the series; nevertheless, all may belong to different subdivisions of the Miocene period. Professor Sedgwick and Mr. Murchison have suggested that the inferior, or first group, which comprises the strata between the Alps and the coralline * Geol. Trans., Second Series, vol. iii. p. 385. t Ibid., p. 390. Cb.XV.] VOLHYNIA-PODOLIA-MONTPELLIER. 215 limestone of Wildon, may correspond in age to the Paris basin ; but the list of fossils which they have given, seems rather to favour the supposition, that the deposit is of the Miocene era. They enumerate four characteristic Miocene fossils,-Mytilus Brardii, Cerithium pictum, C. pupreforme, and C. plicatum,and if there are some few of the associated shells common to the Paris basin, such a coincidence is no more than hold~ true in regard to all the European Miocene formations. On the other hand, the third or newest system, which over~ lies the coralline limestone, contains fossils which do not appear to depart so widely from the Miocene type as to authorize us ~o separate them. 'rhey appear to agree with the tertiary strata of a great part of Hungary and Transylvania, which will be seen, by the tables of shells in Appendix I., to be referrible to the Miocene period. Volhynia and Podolia.-We may expect to find many other districts in Europe composed of Miocene strata, and there ap~ pears already to be sufficient evidence that the marine deposits of the platform of Volhynia and Podolia were of this era. The fossils of that region, which is bounded by Galicia on the west, and the Ukraine on the east, and comprises parts of the basins of the Bog and t~1e Dniester, has been investigated by Von Buch, Eich wald, and Du Bois, and the latter has given excellent plates of more than one hundred fossil shells of the country, which M. Deshayes finds to agree decidedly with the fossils of the Miocene period*. "rhe formation consists of different rocks, sand and sand~ stone, clay, coarse limestone, and a white oolite, the last of which is of great extent. Monlpellier.-The tertiary strata of Montpellier contain many of the Dax and Bordeaux species of shells, so that they are probably referrible to the Miocene epoch ; but in the catal~ g~e given by M. Marcel de Serres, many Pliocene species, s1m1lar to those of the Subapennine beds, are enumerated. * Conch, Foss. du Plateau Wolhyni·Podo, par F. duBois. Berlin, 1831. |