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Show JSLAND LIFE. [t'ART II. --- . . 1 ~ changes of land and and pleasant IS It to spccu ate on J.ormer . . . d · k t offered by anomalies sea with whiCh to cut the gor 1an no . . of distribution, that we still continually meet WJ.th suggestiOns · 1 · · ery diroctwn across the of former contments stretc nng m ev . deepest oceans, in order to explain the presence In rem.ote parts of the globe of the same genera even of pla~~s. or of msectsorganisms which possess such exceptional facihtws bo.th .~or t.errestrial, aerial, and oceanic transport, and. of W~lose d1Stnbut10n in past ages we generally know a.bso.lut~ly nothmg. . The BiTds of MadagascaT, as tnd~cattn~ a ~upp.osed Le1n1l1'Wn conti.nent.·-Having thus shown how the d1stnbutwn of t?e land mammalia and reptiles of MadagaRcar may be well cxplamed by the supposition of a union with Africa before the grea~er part of its cxistina fauna had reached it, we have now to cons1dcr whether, as som~ ornithologists think, the distribution and affinities of the birds present an insuperable objection to this view, and require tho adoption of a hypothetical continent-Lomuriaextending from Madagascar to Cey Ion and tho Malay Islands. There are about one hundred land birds known from the island of Madagascar, all but four or five being peculiar ; and about half of those peculiar species belong to peculiar genera,, many of ·which are extremely isolated, so that it is often difficult to class them in any of the recognised families, or to determine their affinities to any living birds. Among the other moiety, belonging to known genera, we find fifteen which have undoubted African affinities, w bile five or six are as decideJ.ly Oriental, the genera or nearest allied species being found in India or the Malay Islands. It is on the presence of these peculiar Indian types that Dr. Hartlaub, in his recent work on tho Birds of Madagascar and the Adjace11t Islands, lays great stress, as proving the former existence of "Lemuria;" while he considers the absence of such peculiar African families as the plantain-eaters, glossy-starlings, ox-peekers, barbets, honeyguides, hornbills, and bustards-besides a host of peculiar African genera-as sufficiently disproving the statement jn my Geographical Distribution of Animals that Madagascar is "more nearly related to the Ethiopian than to any other region," nnd that its fauna was evidently "mainly derived from Afric::L." cnAr. XIx.] 'l'Ifli: :MADAGASCAH GROUP. 305 But the absence of the numerous peculiar groups of African birds is so exactly parallel to the same phenomenon among mammals, that we are justified in imputing it to the same cause, the more especially as some of the very groups that arc wanting-the plantain-caters and the trogons, for ex[tmple, -are actually known to have inhabited Europe along with the large mammaJia which subsequently migrated to Africa. As to t~1.e pecul.iarly E~stern genera-such as Copsychus and HypSlpetos, w1th a D1erurus, Ploceus, a Cisticola, and a Scops, all clo~o~y allied to Indian or Malayan species-although very stn kmg to the ornithologist, they certainly do not outweicrh the fourteen African genera foun(l in :Mad~gascar. Their p;esenco may, moreover, be accounted for more satisfactorily than by moans of an ancient Lomurian continent, which, even if granted, wouU not explain tho very facts adduceJ. in its support. I.-~ot us first prove this latter statement. The supposed "Lomuria" must have existed, if at all, at so remote a period that the higher animals diu not then inhabit o~ther Africa or Southern Asia, and it must have become partmlly or wholly submergo<l before they roached those countries; otherwise we should find in Madagascar many other animals besides Lemurs, Insectivora, and Viverridre, especially such active arboreal creatures as monkeys and squirrels, such hardy grazers as deer or antelopes, or such wide-ranging carnivores as foxes or bears. This oblige~ us to date the disappe.:~rance of the hypothetical continent about the earlier part of the Miocene epoch at latest, for during the latter part of that period we know that such animals existed in abundance in every part of the great northern continents wherever we have found oraanic remains. But the Oriental birds in Madagascar, by whose 0 prosene~ Dr. Hartlaub upholds the theory of a Lemnria, are slightly modified forms of existing Indian genera, or sometimes, as Dr. Hartlaub himself points out, species haTdly distinguishable frorn those of India. Now all the evidence at our command leads us to conclude that, even if these genera and species were in existence in tho early Miocene period, they must have had a widely different distribution from what they have now. Aloncr with so many African and Indian genera of mammals they tho~ |