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Show 280 TSLAND LTFID. (J'AR'l' II, it is almost exclusively migratory birds that annually reach the Azores and Bermuda; while the corresponding fact that the seeds of those plants, which are common to the Galapagos and the adjacent continent, have all-as Sir Joseph Hooker states-some special means of diRper. nl, is equally intelligible. The reason why the Galapagos posse:;s four times as many peculiar species of plants as the Azores is clearly a result of the less constant introduction of seeds, owing to the absence of storms; the greater antiquity of the group, allo\ving more time for specific change ; antl the influence of cold epochs and of alteration-s of sea and land, in bringing somewhat different sots of plants at different times within the influence of such modified winds and currents as might convey them to the islands. On the whole, then, we have no difficulty in explaining the probable origin of the flora and fauna of the Galapagos, by means of the illustrative facts and general principles already adduced. CHAPTER XIV. ST. HELENA. Position and physical features of St. Helena-Change effected by European occupation-1'he Insects of St. Helena-Coleoptera-Peculiarities and origin of the Coleoptera of St. Helena-Land-shells of St. HelenaAbsence of Fresh-water organisms-Native vegetation of St. HelenaThe relations of the St. Helena Compositre-Concluding Remarks on St. Ilelenu. IN order to mustmte as completely as possible the peculiar phenomena of oceanic islands, we will next examine the organic productions of St. Helena and of the Sandwich Islands, since these combine in a higher degree than any other spots upon the globe, extreme isolation from all more extensive lands, with a tolerably rich fauna and flora whose peculiarities are of surpassing interest. Both, too) have received considerable attention from naturalists; and though much still remains to be done in the latter group, our knowledge is sufficient to enable us to arrive at many interesting results. ·Position and Physical feat~wes of St . .lielcna.-This island is situated nearly in the middle of the South Atlantic Ocean, being more than 1,100 miles from the coast of Africa, and 1,800 from South America. It is about ten miles long by eight wide, and is wholly volcanic, consisting of ancient basalts, lavas, and other volcanic products. It is very mountainous and rugged, bounded for the most part by enormous precipices, and rising to a height of 2, 700 feet above the sea-level. An ancient crater, about four miles across, is open on the south siue, and its |