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Show ~44 DltiFT-WOOD OF TllE NORTil SEA. tch. XV. Th e anc1. en t ~to res t s of Iceland ' as Malte-Brun observes, have oeen 1. mprov1' d en tl y ex h au sted., but ' althouOo 'h . the Ic.e lan• der can ob tam. no tl. m b er f rom tlle land ' he is supphed w1th It abun-d ant1 y b y th e ocean. An immense quantity of thick trunks of pm· es, fi rs, an d o ther trees , are thrown upon the northern coast of the island, especially upon North Cape and Cape L anganess, an d are then carried by the waves along these two promontories to other parts of the coast, so as to afford suf-ficiency of wood for fuel and for constructing boats. Timber is also carried to the shores of Labrador and Greenland ; and Crantz assures us that the masses of floating wood thrown by the waves upon the island of John de Mayen often equal the whole of that island in extent*· In a similar manner the bays of Spitzbergen are filled with drift-wood, which accumulates also upon those parts of the coast of Siberia that are exposed to the east, consisting of larch trees, pines, Siberian cedars, firs, and Fernambucco and Campeachy woods. These trunks appear to have been swept a way by the great rivers of Asia and America. Some of them are brouO'ht from the Gulf of Mexico, by the Bahama stream, while others are hurried forward by the current which, to the north of Siberia, constantly sets in from east to west. Some of these trees have been deprived of their bark by friction, but are in such a state of preservation as to form excellent building timber t· Parts of the branches and almo~t a1l.the roots remain fixed to the pines which have been dnfted mto the North Sea, into latitudes too cold far the growth of such timber, but the trunks are usually barked. . The leaves and lighter parts of plants are sel~om car~Ied out to sea, in any part of the globe, except durmg tropiCal hurricanes among islands, and during the agitations of the atmosphere which sometimes accompany earthquakes and vol· canic eruptions t. C t H. t f Greenland tome i. • Malte-Brun, Geog. vol. v. part i. p. 112.- ran z, 15 .o 1 PP· 50-54. t · 112 t Olafsen, Voyage to Iceland, tome i. Malte-Brun's Geog. vol. v. par 1 ' P· ' : De la Beche, Geol. Manual, p. 477. Ch. XV.] IMBEDDING OF THE REMAINS OF INSECTS. ~45 It. will appear .from these observations, that although the re. mams of terrestrial .v egetation , borne d own b y aqueous causes from the lan.d, are cluefly deposited at the bottom of lakes or at the .mouths. of :ivers, yet a considerable quantity is drifted ~bout Ill all ~IrectiOns by currents, and may become imbedded m any manne formation, or may sink dow n, w1 1 en water-logged, to t~e bott.om of unfathomable abysses, and there accumulate Without Intermixture of other substances. It rna~ be asked w~1ether we have any data for inferring that the remams. of a considerable proportion of the existing species of plants will be permanently preserved, so as to be hereafter recognizable, su~posing .the strata now in progress to be at some future period upraised? To this inquiry we may reply that there are no reasons for expecting that more than a small number of the plants now flourishing in the globe will become fossilized, since the entire habitations of a great number of them are remote fro~ lakes and seas, and even where they gro.w near to large .bodies .of water, the circumstances are quite accidental and partial whiCh favour the imbedding and conservation of vegetable remains. Those naturalists, therefore, who infer that the ancient flora of the globe was, at certain perio~s, less varied than now, merely because they }1ave as yet discovered only a few hundred fossil species of a particular epoch, while the! can enumerate ~ore than fifty thousand living ones, are reasomng on a false basts, and their standard of com ... parison is not the same in the two cases. Imbedding of the Remains of Insects. I IIAVE observed the elytra and other parts of beetles in a band of fissile cla~, separating two beds of recent shell-marl, in the Loch o: Kmnordy. Amongst these, Mr. Curtis recognized Elater lmeatus and Atopa cervina, species still living in Scotland. These, as well as other remains which accompanied them, appear to belong to terrestrial, not aquatic species, and must have been carried down in muddy water during an inundation. |