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Show 452 PERU. July, 1835. plaited rush, and the head of a stalk of Indian corn. This fact, coupled with another, which will be mentioned, proves I think the amount of eighty-five feet elevation since man inhabited this part of Peru. On the coast of Patagonia and La Plata, where perhaps the movements have been slower, there is evidence, as we have seen, that several mammalia have become extinct during a smaller change of level. At Valparaiso, where there exist abundant proofs of recent elevation to a greater altitude than in this part of Peru, I can show that the greatest possible change during the last 220 years, has not exceeded the small measure of fifteen feet. On the mainland in front of San Lorenzo, near Bellavista, there is an extensive and level plain, at the height of about a hundred feet. The section on the coast shows that the lower part consists of alternating layers of sand· an:d impure clay, together with some gravel; and the surface, to the depth of from three to six feet, of a reddish loam, containing a few scattered sea-shells, and numerous small fragments of coarse red earthenware. At first I was inclined to believe that this superficial bed must have been deposited beneath the sea; but I afterwards found in one spot, that it covered an artificial floor of round stones. The conclusion which then seemed most probable was, that at a period when the land stood at a less height, there was a plain very similar to the one now surrounding Callao, which being protected by a shingle beach, is raised but very little above the level of the sea. On this plain, with its clay beds, I imagine the Indians manufactured their earthen vessels ; and that, during some violent earthquake, the sea broke over the beach and converted the plain into a temporary lake, as happened in 1713* around Callao. The water would then deposit mud, containing fragments of pottery from the kilns, and shells from the sea. This bed with fossil earthenware occurring at>Ubout the same altitude with the terrace on San Lorenzo, confirms the supposed amount of elevation within the human period. • Frezier's Voyage. 453 t ~ 1 CHAPTER XIX. Islands volcanic-Number of craters-Leafless bushes-Colony at Charles Isla~d-James Is~and-Salt-lake in crater-Character of vegeta.tionOrmtholog~, cu.nous finches-Great tortoises, habits of, paths to the wel~s-Mar~ne lizard feeds on sea-weed-Terrestrial species, burrowing hab1ts: herb~vorous-Importance of reptiles in the Archipelago-Few and ~m~te msects- American type of organization-Species confined to certam 1slands-Tameness of birds-Falkland Islands-Fear of man an acquired instinct. GALAPAGOS ARCHIPELAGO. SEPTE.~BER 15TII.-The Beagle arrived at the southernmost of the Galapagos islands. This archipelago consists of ten principal islands, of which five much exceed the others in size. They are situated under the equatorial line, and between five and six hundred miles to the westward of the coast of America. The constitution of the whole is volcanic. Wi:h the exception of some ejected fragments of granite, whiCh have been most curiously glazed and altered by the heat, every part consists of lava, or of sandstone resulting from the attrition of such materials. The hiO'her islands • 0 ' (whiCh attain an elevation of three, and even four thousand feet) generally have one or more principal craters towards their centre, and on their flanks smaller orifices. I have no exact data from which to calculate, but I do not hesitate to affirm, that there must be, in all the islands of the archipelago, at least two thousand craters. These are of two kinds ; one, as in ordinary cases, consisting of scorire and lava, the other of finely-stratified volcanic sandstone. The latter in most instances have a form beautifully symmetrical: their origin is due to the ejection of mud,-that is, fine volcanic ashes and water,-without any lava. Considering that these islands are placed directly under the equator, the climate is far from being excessively hot; a |