ANNOTATIONS AND ADDITIONS. 269 



and Ponpynete (one of the Carolinas) ; and lastly, coral banks en- 

 closing 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 ana- 

 tomical 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 Keinhold 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 lati- 

 tude, to the general system of mountains and the configuration of 

 the earth's surface in Central Asia. They form a kind of continua- 

 tion 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 



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