Page:Popular Science Monthly Volume 37.djvu/322

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308
THE POPULAR SCIENCE MONTHLY.

and the surrounding peninsulas. Quite a fossil forest is buried under the ferruginous mass of Mount Atanekerdluk, a peak which rises to a height of over a thousand feet over against Disco, and which is now surrounded by glaciers on all sides. From these deposits Whymper, Nordenskjöld, and others have extracted one hundred and sixty-nine species of plants, of which about three fourths were shrubs and trees, some with stems as thick as a man's body. Altogether there have been discovered in the Greenland strata as many as six hundred and thirteen species of fossil plants. The most prevalent tree is a Sequoia, closely resembling the Oregon and Calif ornian giants of the present epoch. Associated with this conifer were beeches, oaks, evergreen oaks, elms, hazel-nuts, walnuts, magnolias, and laurels; and these forest trees were festooned with the vine, ivy, and other creepers. A leaf of a Cycadea found among these fossil remains is the largest ever seen; and a true palm, the Flabellaria, has been discovered among the remains of these old arctic forests.

To develop such a flora the climate of north Greenland must at that time have been analogous to that at present enjoyed on the shores of Lake Geneva, twenty-four degrees nearer to the equator. According to the same gradation of temperature, the dry lands about the north pole itself must at the same epoch have had their forests of aspens and conifers. According to Oswald Heer, the change that has taken place in the climate since then represents a fall of 30° or 40° Fahr. for north Greenland. The interval between these two ages was marked by the Glacial period, whose traces are visible on the west coast.

Although incomparably poorer than that of Miocene times, the present flora of Greenland is sufficient to clothe extensive tracts with a mantle of mosses, grasses, and brushwood. Wherever the snows melt under the influence of the sun or of the warm east winds, herbaceous and other lowly plants spring up even on the exposed nunatakker, and to a height of five thousand feet. Owing to the uniform intensity of the solar heat, the summer flora is almost identical on the low-lying coast-lands and highest mountain-tops. True trees occur in the southern districts, where Egede was said to have measured some nearly twenty feet high. But the largest met by Rink during all his long rambles was a white birch fourteen feet high growing amid the rocks near a Norse ruin. Few trees, in fact, exceed five or six feet, while most of the shrubs become trailing plants. Such are the service and alder, which on the coast reach 65° north latitude; the juniper, which advances to 67°; and the dwarf birch, which ranges beyond 72°.

In its general features the Greenland flora, comprising about four hundred flowering plants and several hundred species of lichens, greatly resembles that of Scandinavia. Hooker and Dr.