Page:Quarterly Journal of the Geological Society of London, vol. 34.djvu/102

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68
PROF. O. HEER ON FOSSIL PLANTS DISCOVERED IN

It is a very interesting fact that in Grinnell Land two twigs of the Spruce (Pinus abies, Linn.) still covered with leaves were found. I had already received single detached leaves from Spitzbergen; with them there were seeds of this species, and, further, there was also found a scale of the cone (see my "Miocene Mora of Spitzbergen" in the 'Flora foss. Arctica,' ii. tab. v. fig. 35–49); so that the species could be determined with perfect certainty. We therefore see that our Spruce (Red Fir) was living during the Miocene period in Grinnell Land as well as in North Spitzbergen, and at that time doubtless extended as far as the pole, at least if any dry land then existed there. In Europe the tree did not then exist; hence very probably it had its original home in the extreme north, and has thence extended southwards. We first meet it in Europe in the Forest-bed of the Norfolk coast, and in the interglacial deposits of lignites in Switzerland. At that time, therefore, it had come into our regions, and has ever since formed a principal constituent of our forests. Its extreme northern limit is now in Scandinavia, latitude 691/2° N.; and it is now spread over about 25 degrees of latitude, whilst during the Miocene period it was limited to the Arctic zone. The case is quite different with Taxodium distichum, the second species of tree which Miocene Grinnell Land had in common with the flora of the present day; for during the Miocene period it extended from Central Italy up to 82° N., and was spread over all portions of the northern hemisphere, whilst at present it is confined to a comparatively small area.

Tsuga forms a third subgenus of Pinus occurring in Grinnell Land, to which we must refer the Pinus Dicksoniana, Heer; small twigs covered with leaves, and one seed, were found, as at Cape Staratschin. The species resembles the American Hemlock-Spruce (P. canadensis). To these must be added some large needles which seem to indicate a Fir of the group of Pinus grandis and P. lasiocarpa.

The Monocotyledons are represented in Grinnell Land by reeds and fragments of leaves belonging to Phragmites œningensis, a species which has also reached us from Greenland and Spitzbergen, and shows that the damp localities were covered with large reeds; narrow leaves with a midrib, which lie along with them, indicate a Carex (C. noursoakensis, Heer), with which we are also acquainted from Greenland and Spitzbergen.

Of Dicotyledons Captain Feilden's collection contains 8 species belonging to 6 families—Salicineæ, Betulaceæ, Cupuliferæ, Ulmaceæ, Caprifoliaceæ, and Nymphæaceæ.

The Arctic Poplar (Populus arctica, Heer) is an old acquaintance, which one can trace over the whole Arctic zone, and which is one of its most abundant trees; of the two species of Birch, one (Betula prisca) is also abundant in high northern latitudes; and the occurrence of a pretty large piece of bark in Grinnell Land, and of a still larger piece in Spitzbergen, shows that the species formed trees of considerable size.

The second species of Birch from Grinnell Land (Betula Brongniarti, Ett.) is the only European species of plant from Grinnell Land which was not previously known from the Arctic zone.