Page:Quarterly Journal of the Geological Society of London, vol. 28.djvu/197

 for me to confirm this classification in detail. I have discussed it more fully in my treatise, which will be published by the Swedish Academy, and have illustrated the plants in fourteen plates.

The Yellow Sandstone of Ireland is well known to lie immediately under the Carboniferous Shale, which, in its turn, is covered by the Mountain Limestone. It is regarded as the Upper Old Red, and, as such, is classed with the Devonian. But the flora of the Yellow Sandstones of Kiltorkan and the shales of Tallowbridge quite contradict this classification. I owe to the kindness of Messrs. W. H. Baily and Robert H. Scott a collection of plants from these localities, which have enabled me to make a comparison. It contains, from Tallowbridge, Calamites radiatus, Lepidodendron Veltheimianum, and Knorria acicularis ; and, from the Yellow Sandstone of Kiltorkan, Calamites radiatus, in large pieces, Cyclostigma Kiltorkense, G. minutum, Lepidostrobus Bailyanus, Schimp., Lepidodendron Veltheimianum, Stigmaria ficoides, and Paloeopteris hibernica, Forb. sp., to which also Sphenopteris Hookeri, and S. Humphriesiana may be added.

The flora of Tallowbridge therefore, so far as it is known, agrees very nearly with that of Kiltorkan ; and both of them coincide in a remarkable manner with that of Bear Island ; for, of the ten Irish species, five or six are common to the latter. Paloeopteris hibernica, of which beautiful fronds are found at Kiltorkan, has not yet, it is true, been discovered in Bear Island ; but the nearly allied Paloeopteris Roemeriana, Gopp. sp., has been found there ; Calamites, Lepidodendron, and Knorria are represented by important common species ; and the two Cyclostigmata, which were formerly known only from the south of Ireland, reappear in the distant Bear Island. The complete agreement of such a relatively large number of species at such far distant localities, these species being besides of such frequent occurrence as to be true typical plants, leaves hardly any doubt that these floras must have belonged to the same epoch in time.

We have already seen that the Bear-Island flora is so nearly related to that of the Mountain Limestone and the Millstone-grit, that it must be classed with this and not with the Devonian. Therefore the flora of Kiltorkan must also belong to the Lower Carboniferous, and we must draw the line of separation between the Devonian and the Carboniferous below the Yellow Sandstone. It follows necessarily that the overlying Carboniferous shales must belong to the Lower Carboniferous, to which they are also more nearly allied by their marine remains than to the Devonian, as appears from the lists which Mr. Baily has published. The fish-remains from Kiltorkan present the only difficulty ; for they agree more with those of the Old Red : but so long as no species are found which are decidedly identical with those of the Old Red of Scotland, these fish-remains can by no means be said to contradict the classification founded on the plants of the Yellow Sandstone of Kiltorkan, which confirms the published views of Sir R. T. Griffith, Prof. Haughton, and Mr. Symonds. These fish- remains only show that some genera, which were formerly regarded as belonging exclusively to the Old