Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/636

12 GEOLOGICAL MEMOIRS. bergen. The Carboniferous flora numbers 12 species, the Cretaceous 14 species, some of which are identical with those in European strata. The Miocene flora numbers 162 species, of which 112 are new, while very few are referable to forms actually living in those regions. Central and South European, Japanese, and especially Asiatic and American types are found. Taxodium dubium, Sequoia Langsdorfii, Alnus Kefersteini, Fagus Deucalionis, and Platanus aceroides, are the prevailing forms. Palms, fine-leaved Leguminoscoe, and Cinnamomum are absent. It may be concluded from the general character of this flora that the mean annual temperature of the Arctic regions was not lower than 48° Fahr.

The deposits of this period are in these regions intimately connected with the eruptive rocks and their tuffs. The sandstones, with large plates of mica, in Greenland and Iceland, and their yellowish-white tuffs, call to mind the tuffs of Gleichenberg, and other German trachytic and rhyolitic tuffs in which Palms do not occur. Several Arctic forms, as Sequoia Langsdorffi, Phragmites (Eningensis, Salix macrophylla, Betula prisca, Fagus Deucalionis, Planera Ungeri and Platanus aceroides are characteristic of the Congerian and Sarmatian strata. A petiolate Proteacean leaf mentioned by Mr. D. Stur as allied to Hakea Erdobenjensis, a Hungarian Miocene species, may possibly be referable to MacClintockia Lyelli. The lower beds of the Vienna and Hungarian basins include few eruptive rocks and tuffs, but they are everywhere connected with strata containing the remains of Palms. The entire absence of Palms from the Arctic and European Sarmatian tuffs is far from being certain, and until the presence of Castanea Kubinyi and Parrotia pristina in the Polar regions has been established, no comparison can be made between the Arctic tuffs and those of the Sarmatian horizon. Possibly, sedimentary rocks of older date than the Miocene may be completely absent from the Polar regions, as they are in the grand valley of Hungary. This supposition admitted, the American and European floras may have been connected during the older Miocene period without the intervention of a hypothetical Atlantis. [Count M.]

On the Geology of the Altai Mountains. By Prof. Bernhard von Cotta.

[Proc. Imp. Geol. Institute, Vienna, March 2, 1869.]

Professor Cotta, who visited the Altai group during the summer of 1868, at the request of the Russian Government, with the special object of investigating the metalliferous deposits of those mountains, gives the following account of their geology. The principal rocks of the Altai are:—

1. Crystalline slates. 2. Silurian slates. 3. Devonian limestone. 4. Carboniferous limestones, shales, and sandstones.