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Show 296 TiERRA DEL FUEGO. June, 1834. Mr. Lyell of the Siberian plains, with their innumerable fossil bones, the relics of many successive generations, there can be little doubt that the beds were accumulated either in a shallow sea, or in an estuary. From the description given in Beechey's voyage of Eschscholtz Bay, the same remark is applicable to the north-west coast of America : the formation there appears identical with the common littoral deposits* recently elevated, which I have seen on the shores of the southern part of the same continent. It seems also well established, that the Siberian remains are only exposed where the rivers intersect the plain. With this fact, and the proofs of recent elevation, the whole case appears to be precisely similar to that of the Pampas : namely, that the carcasses were formerly floated into the sea, and the remains covered up in the deposits which were then accumulating. These beds have since been elevated ; and as the rivers excavate their channels the entombed skeletons are exposed. Here then, is the difficulty : how were the carcasses preserved at the bottom of the sea ? I do not think it has been sufficiently noticed, that the preservation of the animal with its ~esh w~~ an occasional event, and not directly consequent on Its position far northward. Cuviert refers to the voyage of Billing as showing that the bones of the elephant buffalo an d r hm. oceros, are nowhere so abundant as on the' islands' between the mouths of the Lena and Indigirska. It is even said that. excepting some hills of rock, the whole is composed of sand, Ice, and bones. These islands lie to the northward of the place where Adams found the mammoth with its flesh preser:ed, and even ten degrees north of the Wiljui, where the rhmoceros was discovered in a like condition. In the case of the bones we may suppose that the carcasses were • See some remarks by Dr. Buckland on the similarity of this formation with the deposits so commonly found over a great part of E A d . , urope. ppen IX to Beechey s Voyage, p. 609. t Ossemens Fossiles, vol. i., p. 151. June, 1834. EDIBLE FUNGUS, 297 drifted into a deeper sea, and there remaining at the bottom, the flesh decomposed.* But in the second and more extraordinary case, where putrefaction seems to have been arrested, the body probably was soon covered up by deposits which were then accumulating. It may be asked, whether the mud a few feet deep, at the bottom of a shallow sea which is annually frozen, has a temperature higher than 32°? It must be remembered how intense a degree of cold is required to freeze salt water ; and that the mud at some depth below the surface, would have a low mean temperature, precisely in the same manner as the subsoil on the land is frozen in countries which enjoy a short but hot summer. If this be possible,t the entombment of these extinct quadru- • Under these circumstances of slow decomposition, the surrounding deposits would probably be impregnated with much animal matter ; and thus the peculiar odour perceived in the neighbourhood of the strata containing (ossil bones at Eschscholtz Bay, may be accounted for. See Appendix to Beechey's Voyage. t With respect to the possibility of even ice accumulating at the bottom of the sea, I shall only refer to the following passage taken from the English translation of the Expedition to the East Coast of Greenland, by Captain W. Graah, Danish Royal Navy. "Nor is this the only danger to be apprehended : the ice off this blink, even to a considerable distance from it, being said to shoot up from the bottom of the sea in such a manner, and in such masses, as in many years to make it utterly impassable. How to account for the phenomenon to which I have just adverted I know not, unless by supposing that the bottom of the sea itself is hereabouts like the dry land covered with a thick crust of ice. But whether this crust is formed upon the spot, or is the remains of icebergs and the heavy drift-ice frozen to the bottom during severe winters, or a portion of the land.ice, which loaded with stones and fragments of the crumbling hill has protruded itself into the sea, is a problem impo~sible, perhaps to solve." Again he says: "We passed it without any .accide~t, and without having observed any thing of that upheaving of the Ice off It, to which allusion has been made, though the fact of its occurrence cannot be doubted, the very name of the place, Puisortok, being thence de n.v ed ·" It seems fully established on excellent testimony (see Journ. of Ge~grap!1 • Soc., vol. v., p. 12, and vol. vi., p. 416 ; also a collection of notices m Edinburgh Journal of Nat. and Geograph. Soc., vol. ii., p. 55), that freshwater rivers in Russia and Siberia, and even in England, often freeze at |