A Manual of Elementary Geology / or, The Ancient Changes of the Earth and its Inhabitants as Illustrated by Geological Monuments

by Sir Charles Lyell

In Russia the Permian rocks are composed of white limestone, with gypsum and white salt; and of red and green grits, with occasionally copper ore; also magnesian limestones, marlstones, and conglomerates.

The country of Mansfeld, in Thuringia, may be called the classic ground of the Lower New Red, or Magnesian Limestone, or Permian formation, on the Continent. It consists there principally of, first, the Zechstein, corresponding to the upper portion of our English series; and, secondly, the marl-slate, with fish of species identical with those of the bed so called in Durham. This slaty marlstone is richly impregnated with copper pyrites, for which it is extensively worked. Magnesian limestone, gypsum, and rock-salt, occur among the superior strata of this group. At its base lies the Rothliegendes, supposed to correspond with the Inferior or Lower New Red Sandstone above mentioned, which occupies a similar place in England between the marl-slate and coal. Its local name of Rothliegendes, red-lyer, or "Roth-todt-liegendes," red-dead-lyer, was given by the workmen in the German mines from its red colour, and because the copper has died out when they reach this rock, which is not metalliferous. It is, in fact, a great deposit of red sandstone and conglomerate, with associated porphyry, basaltic trap, and amygdaloid.

Permian Flora.—We learn from the recent investigation of Colonel von Gutbier, that in the Permian rocks of Saxony no less than sixty species of fossil plants have been met with, forty of which have not yet been found elsewhere. Two or three of these, as Calamites gigas, Sphenopteris erosa, and S. lobata, are also met with in the government of Perm in Russia. Seven others, and among them Neuropteris Loshii, Pecopteris arborescens, and P. similis, with several species of Walchia (Lycopodites), are common to the coal-measures.

Among the genera also enumerated by Colonel Gutbier are Asterophyllites and Annularia, so characteristic of the carboniferous period; also Lepidodendron, which is common to the Permian of Saxony, Thuringia, and Russia, although not abundant. Noeggerathia (see [fig. 350.]), supposed by A. Brongniart to be allied to Cycas, is another link between the Permian and carboniferous vegetation. Coniferæ, of the Araucarian division, also occur; but these are likewise met with both in older and newer rocks. The plants called Sigillaria and Stigmaria, so marked a feature in the carboniferous period, are as yet wanting.

Fig. 350.

Noeggerathia cuneifolia. Ad. Brongniart.[307-A]

Among the remarkable fossils of the rothliegendes, or lowest part of the Permian in Saxony and Bohemia, are the silicified trunks of tree-ferns called generically Psaronius. Their bark was surrounded by a dense mass of air-roots, which often constituted a great addition to the original stem, so as to double or quadruple its diameter. The same remark holds good in regard to certain living extra-tropical arborescent ferns, particularly those of New Zealand.

Psaronites are also found in the uppermost coal of Autun in France, and in the upper coal-measures of the State of Ohio in the United States, but specifically different from those of the rothliegendes. They serve to connect the Permian flora with the more modern portion of the preceding or carboniferous group. Upon the whole, it is evident that the Permian plants approach nearer to the carboniferous ones than to the triassic; and the same may be said of the Permian fauna.