Page:The Botany of the Antarctic Voyage.djvu/244

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FLORA ANTARCTICA.
[Fuegia, the

America; it is of an irregularly four-sided figure, bounded on the north by the strait of Magalhaens, and on the east and west respectively by the South Atlantic and South Pacific Oceans, whilst its southern shores are washed by the Antarctic Sea; the main body of land lies between the 53rd and 56th parallels of latitude and the 64th and 70th degrees of west longitude, and its greatest extension is from east to west, indicated by a diagonal of 500 miles. The general appearance of the whole has been aptly compared, by Mr. Darwin, to what would be presented by a partially submerged chain of mountains. These islands are, in fact, formed by the southern termination of the great Cordillera that traverses both Americas, which here trends to the eastward, and whose further extension is probably indicated by South Georgia in the same latitude; and possibly also by Prince Edward's Island, the Crozets, and Kerguelen's Land still more to the east, situated though these be in another ocean. The natural features of Fuegia have been admirably described by various voyagers, and more particularly by Cook, King, Fitzroy, and Darwin, to whose writings I would refer for more particular information. The exposed mountain-tops rise to a height of 7000 feet above the level of the sea, and the lower limit of perpetual snow is reckoned at 3500–4000 feet.

The botanical features exhibited by this country are not circumscribed by its geographical limits; along the north-east shores the very distinct Flora of East Patagonia accompanies the geological formation prolonged there from the Patagonian plains. On the south-west and south sides again, the vegetation is a continuation of that of West Patagonia, and is characteristic of the western flank of the Cordillera, from South Chili to Cape Horn. Thus it is that we find the Andes dividing two botanical regions from the North Polar almost to the Antarctic circle. The greater part of Fuegia is formed by the Andes alone; but the plants of the north-east portion, where the granitic formation of Patagonia introduces a change in the vegetation foreign to that of Tierra del Fuego, will be necessarily included in the present Flora.

The Deciduous Beech (Fagus antarctica), is the most distinguishing botanical production of this country. In company with the Evergreen Beech (F. Forsteri), it covers the land, especially on the west coasts, as far north as the Chonos Archipelago, in latitude 45° south. It is hardly seen in the north-east portions of Fuegia proper, northward of Staten Land, and though abundant on the west flanks of the Andes, through fourteen degrees of latitude, is unknown on the Atlantic side of Patagonia.[1] I have assumed therefore the shores of the

    shores: and again, that the botany of the North Atlantic Islands, the Azores, Madeira, and the Canaries, though these groups are situated in the westerly winds, contain a large proportion of European species. The violence of the perennial westerly gales to the southward of 45° is proverbial amongst sea-faring men; such winds carried H.M.S. 'Chanticleer' from Cape Horn to the Cape of Good Hope, a distance of four thousand miles, in twenty-seven days, and have enabled an oceanic fowl, the Cape pigeon, to maintain its position close to a ship during the whole of that distance; but still I am not inclined to attribute the prevalence of the Fuegian Flora over so vast an area to their influence, when exerted against many other opposing agents.

  1. Trees allied to these seem to have characterized the ancient or fossil flora of Fuegia, for I owe to Mr. Darwin's kindness impressions of the leaves of three apparently distinct species of deciduous Beech, and which are mentioned in that gentleman's journal.