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Show 398 ISLAND LI:F'I~. [t>AH'l' 11. views has been reproduced in a scientific perit1dical,l and tho supposed Lemurian continent is constantly referred to by quasiscientific writers, as well as by naturalists and geologists, as if its existence had been demonstrated by facts, or as if it were absolutely necessary to postulate such a land in order to account for the entire series of phenomena connected with the :M:adagascar fauna, and especially with the distribution of the Lemuridre.2 I think I have now shown, on the other hand, that it was essentially a provisional hypothesis, very useful in calling attention to a remarkable series of problems in geographical distribution, but not affording the true solution of those problems, any more than the hypothesis of an Atlantis solved the problems presented by ·the Atlantic Islands and the relations of the European and North American flora and fauna. The Atlantis is now rarely introduced seriously except by the absolutely unscientific, having received its death-blow by the chapter on Oceanic Islands in the 01·igin of Species, and the researches of Professor Asa Gray on the affinities of the North American and Asiatic floras. But "Lemuria" still keeps its place-a good example of the survival of a provisional hypothesis which offers 1 ':Phe Ibis, 1877, p. 334. 2 In a paper read before the Geological Society in 1874, Mr. II. F. Blan · ford, from the similarity o£ the fossil p~ants and reptiles, supposed that India and South Africa had been connected by a continent, ''and rcmu.inecl so connected with some short intervals from the Permian up to the end of the Miocene period," and Mr. Woodward expressed his satisfaction witlt "this further evidence derived from the fossil flora of the Mesozoic series o£ 1 ndiu in corroboration of the former existence of au old submerged continellt- Lemuria." Those who have read the preceding chapters of the present work will not need to have pointed out to them how utterly inconclusive is the fragmentary evidence derived from such remote periods (even if there were no evidence on the other side) us indicating geographical ch:mges. 'I'he notion that a similarity in the productions of widely separated continents at <my past epoch is only to be explained by the existence of a dil'ect land-conn~ cti_on, ~s entirely opposed to aU that we know of the wide and varying dtstnbutwn of all types at different periods, as well as to the great powers of dispersal over moderate widths of ocean possessed by all auimals except mammalia. It is no less opposed to what is now known of the general p_ermanency of the great continental and oceanic areas; while in this partJCular case it is totally inconsistent (as has been shown above) with tl10 actual facts of the distribution of animals. CHAP. XIX] 'l'llE MADAGASCAn GHOUP. what seems an easy solution of a difficult problem, and has received an appropriate and easily remembered name, long after it has been proved to be untenable. It is now more than four years since I first showed, by a careful examination of all the facts to be accounted for, that tho hypothesis of a Lemurian continent was alike unnecessary to explain one portion of the facts, and inadequate to explain tho remaining portion.1 Since tbat time I have seen no attempt even to discuss the question on general grounds in opposition to my views, nt)r on the other hand have those who have hitherto supported the hypothesis taken any opportunity of acknowledging its wea.kess and inutility. I have therefore here explained my reasons for rejecting it somewhat more fully and in a more popular form, in the hope that a check may thus be placed on the continued re-statement of this unsound theory as if it were one of the accepted conclusions of modern science. The fifasca1·ene I slrtnds. 2-In the Geographical D-ist1·ibution of Animals, a summary is given of all that was known of the zoology of the various islands near Madagascar, which to some extent partake of its peculiarities, and with it form the Malagasy sub-region of the Ethiopian region. As no great additions have since been made to our knowledge of the fauna of these islands, and my object in this volume being more especially to illustrate the mode of solving distributional problems by means of the most suitable examples, I shall now confine myself to pointing out how far the facts presented by these outlying islands support the views already enunciated with reo-ard to the oriO'in b . e of the Madagascar fauna. The Com01·o Islands. -This group of islands is situated nearly midway between the northern extremity of Madagasc.1r and the cuast of Africa. The four chief islands vary between sixteen and forty miles in length, the largest being 180 miles from the coast of Africa, while one or two smaller islets are less than 100 miles from Madugascar. All are volcanic, Great Comoro being 1 Geog?·aphicctl Di.stribution of Animals, Vol. I., p. 272-2!:!2. 2 The term "Mascarene'' is uscU. here in an extended sense to include all the islands near Madagascar which resemble it in their 'animal and vegetable productions. |