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Show CHAPTER XII. OCEANIC ISLANDS :-THE AZORES AND BERMUDA. THE AzoRES, oR WESTERN IsLANDS. . . . Ch' f 1 · 1 features of the Azores- Po~:ntwn and physiCal features- 1e :r,oo og1ca Birds-Origin of the Azorean bird fauna-Insects of the. AzoresLand- shells of the Azores-The flora of the Azores-The dispersal of seeds-Birds as seed-carriers-Facilities for dispersal of Azorean plants -Important deduction from the peculiarities of the Azorean fauna and flora. BERMUDA. Position and physical features-The Red. Clay of Be1:muda- Zoology o~ Bermuda-Birds of Bermuda-Companson of the b1rd faunas of Belmuda and the Azores-Insects of Bermuda-Land Mollusca-Flora of Bermuda-Concluding remarks on the Azores and Bermuda. WE will commence our investigation into the phenomena presented by oceanic islands, with two groups of. the ~ orth Atlantic in which the facts are of a comparat1vely s1mple nature ~nd such as to afford us a valuable clue to a solution of the m~re difficult problems we shall have to deal with further on. The Azores and Bermuda offer great contrasts in physical features, but striking similarities in geographical position. The one is volcanic, the other coralline; but both are surrounded by a wide expanse of ocean of enormous depth, the one being about as far from Europe as the other is from America. Both are situated in the temperate zone, and they differ less than six degrees in latitude, yet the vegetation of the one is wholly temperate, w bile that of the other is almost tropical. The productions of the one are related to Europe, as those of the other are to America, but they present instructive differences; and both ( HAP, Xl i.] OClj~ANIC I~LANDS. 239 afford evidence of the highest valu~ as to the means of dispersal of various groups of organisms across a wide expanse of ocean. THE AZOHES, OR WESTEHN ISLANDS. These islands form a widely scattered group, nine in number, situated between 37° and 39° 40' N. Lat. and stretching in a south-east and north-west direction over a distance of nearly OUTLINE ~lAP OF TJJE AZORES. NoTE.-Tht' light tint shows where the sen is less than 1,000 f!tlhoms deep. The rl~trk tint .. .. , more than 1,000 fathoms deep. '!'he flgures show depths in fathoms. 400 miles. 'l'he largest of the islands, San :Miguel, is about forty miles Jong, and is one of the nearest to Europe, being rather under 900 maes from the coast of Portugal, from which it is separated by an ocean 2,500 fathoms deep. The depth between the islands does not seem to be known, but the 1,000 fathom line encloses the whole group pretty closely, while a depth of n.bout 1,800 fathoms is reached within 300 miles in all directions. These great depths render it in the highest degree |