Page:Quarterly Journal of the Geological Society of London, vol. 34.djvu/100

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PROF. O. HEER ON FOSSIL PLANTS DISCOVERED IN
6. Notes on Fossil Plants discovered in Grinnell Land by Captain H. W. Feilden, Naturalist of the English North-Polar Expedition. By Professor Oswald Heer, F.M.G.S. (Read November 7, 1877.)

In the vicinity of Discovery Harbour, where H.M.S. 'Discovery' wintered during 1875–76, a thick bed of lignite was found. The locality referred to is on the western shore of Robeson Channel, in about latitude 81° 45' N., and longitude 64° 45' W., north-west of Cape Murchison; the exact position is designated Watercourse Ravine in the Charts of the English Expedition.

This coal-bed has a thickness of from 25 to 30 feet, and lies in a depression, the foundation of which consists of the unconformably stratified azoic schists which constitute the chief mass of Grinnell Land. On the coal-bed rest immediately black shales and sandstones. The black, fine-grained shales, which very closely resemble the Taxodium-shale of Cape Staratschin on the Ice-fiord of Spitzbergen, contain many remains of plants, which were collected by Captain Feilden and handed over to me for examination. The coal-seam and the superincumbent beds of shale and sandstone dip to the east under the sea of Robeson Channel at an angle of about 10°. These beds are cut through by a stream which has formed a deep gully, wherein the strata are laid bare; whilst at different points on the upper strata rest beds of fine mud and glacial drift, which contain well-preserved shells of marine Mollusca (Saxicava rugosa, Astarte borealis, &c.) now found in the neighbouring sea. This glacial marine deposit is met with up to a height of 1000 feet above the present sea-level, and shows that the land was sunk beneath the surface of the sea subsequently to the deposition of the lignite and plant-bearing shales, but was again elevated more than 1000 feet. Very probably the lignite-bed and the accompanying plant-bearing shales are to be met with in other parts of Grinnell Land, although hitherto only proved to occur at the place indicated.

Captain Feilden only made two visits, as the plant-bearing nature of the deposit was not discovered until a very late period of the Expedition. This is much to be deplored, as the shales enclose rich botanical treasures.

Captain Feilden's collection contains 26 species; and of these, 18 species are known from the Miocene deposits of the Arctic zone. This deposit is therefore doubtless Miocene. It shares 17 species with Spitzbergen (latitude 76°–79° N.) and 8 species with Greenland (latitude 70°–71° N.). The Grinnell-Land flora consequently more closely approaches the Miocene of Northern Spitzbergen (which lies from 3° to 4° of latitude further south) than that of Greenland (situated almost 11° further south). With the Miocene flora of Europe it has 6 species in common, with that of America (Alaska and Canada) 4, and with that of Asia (Sachalin) 4 also.

Let us now examine these plants somewhat more closely. Of Cryp-