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Show ANNOTATIONS AND ADDITIONS. 269 and Poupynete (one of the Carolinas);-and lastly, coral banks enclosing lagoons, forming "Atolls" or "Lagoon Islands." This highly natural division and nomenclature have been introduced by Charles Darwin, and are intimately connected with the explanation which that ingenious and excellent investigator of nature has given of the gradual production of these wonderful forms. As on the one hand Cavolini, Ehrenberg, and Savigny have perfected the scientific anatomical knowledge of the organization of coral-animals, so on the other hand the geographical and geological relations of coral-islands have been investigated and elucidated, first by Reinhold and George Forster in Cook's Second Voyage, and subsequently, after a long interval, by Chamisso, Peron, Quoy and Gaimard, Flinders, Liitke, Beechey, Darwin, d'Urville, and Lottin. The coral-animals and their stony cellular structures or scaffolding belong principally to the warm tropical seas, and the reefs are found more frequently in the Southern than in the Northern Hemisphere. The Atolls or Lagoon Islands are crowded together in what has been called the Coral-Sea, off the north-east coast of New Holland, including New Caledonia, the Salomon's Islands, and the Louisiade Archipelago; in the group of the Low Islands (Low Archipelago), eighty in number; in the Fidji, Ellice, and Gilbert groups; and in the Indian Ocean, on the north-east of Madagascar, under the name of the Atoll-group of Saya de Malha. The great Chagos bank, of which the structure and rocks of dead coral have been thoroughly examined by Captain Moresby and by Powell, is so much the more interesting, because we may regard it as a continuation of the more northerly Laccadives and Maldives. I have already called attention elsewhere (Asie Centrale, t. i. p. 218) to the importance of the succession of these Atolls, running exactly in the direction of a meridian and continued as far as 7° south latitude, to the general system of mountains and the configuration of the earth's surface in Central Asia. They form a kind of continuation to the great rampart-like mountain elevations of the Ghauts and the more northern chain of Bolor, to which correspond in the trans-Gangetic Peninsula the North and South Chains which are intersected near the great bend of the Thibetian Tzang-bo River by several transverse mountain systems running east and west. In 23* |