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Show 264 ISLAND LIFE. (rART II. no reason to doubt that besides the species that ·have actually established themselves, many others must have reached ~he islands but were not suited to the climate and other physwal conditi~ns, or did not find the insects necessary to their fertilisation. If now we consider the extreme remoteness and isolation of these islands, their small area, and comparatively recent origin, and that, notwithstanding all these disadvantages, they have acquired a very considerable and varied flora and fauna, we shall, I think, be convinced, that with a larger area and greater antiquity, mere separation from a continent by many hundred miles of sea would not prevent a country from acquiring a very luxuriant and varied flora, and a fauna also rich and peculiar as regards all classes except terrestrial mammals, amphibia, and some groups of reptiles. This conclusion will be of great importance in many cases, where the evidence as to the exact origin of the fauna and flora of an island is less clear and satisfactory than in the case of the Azores and Bermuda. CHAPTER XIII. THE GALAPAGOS ISLANDS. Position and physical features-Absence of indigenous Mammalia and Amphibia-Heptiles-Birds-Insccts and Land-shells-The Keeling Islands as illustrating the manner in which Oceauic Islands are peopled-Flora of the Galapagos-Origin of the Flora of the Galapagos-Concluding Remarks. TuE Galapagos differ in many important respects from the islands we have examined in our last chapter, and the differences are such as to have affected the whole character of their animal inhabitants. Like the Azores, they are volcanic, but they are much more extensive, the islands being both larger and more numerous; while volcanic action has been so recent and extensive that a brge portion of their surface consists of barren lavafields. They are considerably less distant from a continent than either the Azores or Bermuda, being about GOO miles from the ~ west coast of South America and a little more than 700 from Veragua, with the small Cocos Islands intervening; and they are situated on the equator instead of being in the north temperate zone. They stand upon a deeply submerged bank, the 1,000 fathom line encircling all the more important islands at a few miles' distance, whence there appears to be a comparatively steep descent all round to the average depth of that portion of the Pacific, between 2,000 and 3,000 fathoms. The whole group occupies a space of about 300 by 200 miles. It consists of five large and twelve small islands; the largest (Albemarle Island) being about eighty miles long and of very |