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Show 508 ISLAND LIFE. (PAR'l' II, most recent origin and offering the simplest phenomena; and b · 'th the British Isles as affording the best example of egm WI 1 d R · · t d well known Continental Is an s. evwwmg very recen an . . h · · the interesting past history of Bnta1~, we show .w Y.It IS com-t. 1 poor in species and why th1s poverty IS still greater para 1ve y ' . d fl · in Ireland. By a careful examination of 1ts fauna an ora 1t is then shown that the British Isles are not so completely identical, biologically, with the continent as has be:n supposed. A onsiderable amount of speciality is shown to exist, and that thi~ speciality is real and not apparent is supported by the fact, that small outlying islands, such as the I~le of Man, the Shetland Isles, Lundy Island, and the Isle of WIght, all possess certain species or varieties not found elsewhere. Borneo and Java are next taken, as illustrations of tropical islands which may be not more ancient than Britain, but which, owing to their much larger area, greater dista~ce from the continent and the extreme richness of the eq uatonal fauna and flora, pos;ess a large proportion of peculiar species, t~ough these are in general very closely allied to those of the adJacent parts of Asia. The preliminary studies we have made enable us to afford a simpler and more definite interpretation of the peculiar relations of Java to the continent and its differences from Borneo and Sumatra, than was given in my former work ( 1'he Geographical Distribut'ion of Animals). . Japan and Formosa are next taken, as. examples of islands which are decidedly somewhat more anCient than those previou~ ly considered, and which present a number of very interesting phenomena, especially in their relations to each o~he~, and to remote rather than to adjacent parts of the Asmtw continent. We now pass to the group of Ancient Continental Islands, of which Madagascar is the most typical example. It is surrounded by a number of smaller islands whic~ may be. te:1~ed its satellites since they partake of many of 1ts pecuhanbes; thouah some of these-as the Comoros and Seychelles may be considered continental, while others-as Bourbon, Mauritius, and Rodriauez-are decidedly oceanic. In order to understand the pecul~rities of the Madagascar fauna we have to consider CIIAP. l{XIv.) SUMlHARY AND CONCLUSION. 509 ~he past history of the African and Asiatic continents, which it . 1s shown are such as to account for all the main peculiarities of the fauna of these islands without havinO' recourse to the hypothesis of a now-submerged Lemurian co~tinent. Considerable ,evidence is further adduced to show that "Lemuria" is a ·myth, since ~ot only is its existence unnecessary, but it can be proved .t~at It would not explain the actual facts of distribution. The ongm of the interesting Mascarene wingless birds is dis-· cussed, and the main peculiarities of the remarkable flora ?f Madagascar and the Mascarene islands pointed out; while it IS shown that all these phenomena are to be explained on the gen~ral princ~ples of the permanence of the great oceans and the. comparatively slight fluctuations of the land area, and by takmg account of established palooontological facts. ~here remain two other islands-·Celebes and New Zealand, w hwh are classed as " anomalous," the one because it is almost impossi.ble to place i~ in any of the six zoological regions, or dete:mme whether It has ever been actually join~d to a contment-the other because it combines the characteristics of continental and oceanic islands. The pecul~arities of the Celebesian fauna have already been dwelt upon m several previous works, but they are so remarkable and so unique that they cannot be omitted in a treatise on " Insular Faunas ; " and here, as in the case of Borneo and Ja.va,. fuller .consideration and the application of the general pnn01ples lmd down in our First Part, lead to a solution of the problem at once more simple and more satisfactory than any which have been previously proposed. I now look upon Celebes as an outlying portion of the great Asiatic continent of Miocene times, which either by submergence or some other cause had lost the greater portion of its animal inhabitants, and since then has remained more or less completely isolated from every other land. It has thus preserved a fragment of a very ancient fauna along with a number of Inter types which have reached it from surrounding islands by the ordinary means of dispersal. This sufficiently explains all the peculiar affinities of its animals, though the peculiar and distinctive characters of some of them remain as mysterious as ever. |