Geography.-New Guinea, the larger islands of the Bismarck Archipelago and the Solomon Group, and New Caledonia are old land masses; but nearly all the other islands of Melanesia are of ancient origin. Of these many are volcanic, such as the Northern New Hebrides and the Fiji Group, while the remainder are coral islands, like Santa Cruz, or composed of raised coral beaches, as Vate and Erromanga and the Loyalty Islands, sometimes with deep sea deposits, which prove elevation from considerable depths. Hence the natives of purely coral islands are dependent upon shells with which to make their implements...