Page:Encyclopædia Britannica, Ninth Edition, v. 7.djvu/290

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272 DISTRIBUTION [ANIMAL. world. Among beetles the Lucanidce, Cetoniidce, and Bu- prestidce are especially remarkable, while the elegant Longi- corns have their full quota of curious and beautiful forms. Subdivisions of the Oriental Region. These are tolerably well marked, though very unequal in extent and productiveness. The Himalayan slopes with all the Indo-Chinese countries form the chief and most typical part of the region. Here are the greatest variety of Mammalia and birds, and almost all the more important groups are represented. Three genera of Mammalia and 44 of birds are peculiar to this sub-region. The Malay Peninsula, with the larger Malay islands, as far as Java, Borneo, and the Philippines, form a sub-region which has much in common with the last, and is almost equally rich, and in some groups even richer and more peculiar. Thus it has no less than 14 genera of Mammalia and more than 40 genera of birds which are wholly peculiar to it, among which are such interesting forms as the orang-utans (Si-mia), the spectre-lemur (Tarsius), the flying- lemur (GaJcopithccus), the feather-tailed tupaia (Ptilocerus), the sun- bear (Ilclarctos), and the magnificent argus-pheasants (Argusianus). About an equal number of genera are common to the Malayan and the Indo-Chinese sub-regions, but are not found elsewhere ; so that the two have much in common, and together comprise nearly all that is most remarkable and beautiful of the Oriental fauna. The other two sub-regions consist of the peninsula of India and Ceylon, whose chief feature is their comparative zoological poverty. Taking first what may be termed the Indian sub-region, extending from the foot of the Himalayas to the Carnatic, we find that this extensive and fertile region, though abounding in life of every kind, yet possesses no peculiar genus of either Mammalia or birds ; while, favoured by the open and arid plains of which much of the surface consists, some African types are more abundant than in other parts of the region, though these are numerically unim portant. Ceylon and Southern India are somewhat more interesting, as they possess some peculiar forms, and others in common with the Malay islands. Among the former is Loris, a peculiar lemur ; and there is a peculiar genus of Muridcc, as well as one or two peculiar genera of birds. There are also several peculiar species of monkeys, and the Malayan genus Tupaia; while among birds we find Malayan forms of cuckoos and Timaliidcc. The reptiles, however, best characterize this sub-region, as it possesses an entirely peculiar family of snakes (UropeUidce), consisting of 5 genera and 18 species, as well as 4 other peculiar genera of snakes. There are also many peculiar genera of lizards belonging to HieAgamidccandAcontiadce, and 3 peculiar genera of tailless Batrachia. The insects also offer some remarkable cases of Malayan affinity, the genus Hcstia (or spectre-butterflies) being found in Ceylon only beyond the Malay islands ; while 6 genera of Malayan Longicorns and the wingless Tricondyla belonging to the Cicindelidcc, are in the same category. The combination of so many peculiarities justifies the separation of Ceylon and a portion of Southern India as a distinct Oriental sub-region. IV. The Australian Region. On entering this region we meet with such a radical change in all the higher forms of life, that the zoologist seems to have got into a new world. Even the Austro-Malay islands, though differing in no way in climate or luxuriance of vegetation from the Indo-Malay islands to the west of them, exhibit this change in an almost equally marked degree. With the exception of Celebes, which is a debatable land hardly belonging to either region, the other islands only posssess a few deer and pigs to represent the host of varied Mammalia from the elephant and tapir to the squirrel and monkey which characterize every part of the Oriental region to its extreme south-eastern limits in Java and Borneo. In place of these we have Marsupials only, in great variety in the extensive country of Australia and less abundantly in the islands ; and besides these, only those flying mammals the bats, which can traverse the ocean, and the smallest forms of rodents, the mice which may be occasionally carried by floating trees or other accidental means across narrow arms of the sea. There are 5 distinct families and 33 genera of Australian Marsupials, as w r ell as 2 families and genera of the still more lowly-organized Motiotremata which comprise the anomalous Ornithorhynchus and Echidna. Birds, as might be expected, are not so excessively peculiar, a large number of almost cosmopolitan families extending into Australia ; yet there are no less than 16 families altogether characteristic of the region, among which are such remarkable forms as the Paradise-birds (Faradi- sceidce), the honey-suckers (Hdiphagidce], the lyre-birds (Menuridce),thQ cockatoos ( Cacatuidce),the lories (Trichoglos- sidce), the mound-builders (Megapodiidas), and the casso waries (Casuariidce). Among the important groups which are entirely wanting in Australia are the barbets (Megalfpmidce), the woodpeckers (Picidce, otherwise cosmopolitan), the trogons (Trogonid<z),fuid. the pheasants (Phasianidce). The reptiles, as in most other cases, offer less marked peculiari ties than the birds ; but a large proportion of the genera are peculiar, and there are even 3 peculiar families of lizards, as well as the singular HaUeria of New Zealand, which constitutes not only a separate family but a new order of reptiles. The Amphibia and fresh- water fishes present a corresponding amount of peculiarity ; and the recent discovery of the genus Ceratod-iis (the mud-fish) is very interesting, since its nearest allies appear to have lived early in the Secondary period, while other members of the same group are found isolated in the rivers of tropical Africa and America. Insects are very abundant in Australia and the Austro- Malay islands ; but owing to the various means by which these small creatures are conveyed across the seas, and tho identity of physical conditions in the Oriental and Australian portions of the archipelago, the true Australian fauna is chiefly developed in Australia itself, where there are a considerable number of peculiar genera in all orders of insects. Subdivisions of the Australian Region. Besides the Australian continent, which is by far the richest and most important part of the region, there are three groups of islands which have each some distinctive peculiarities. These are the Anstro-Malay islands, comprising New Guinea, the Moluccas, and the Timor group; the Pacific islands; and the New Zealand group. The first is very rich, especially in birds and insects while the other two are exceed ingly poor. The Austro-Malayan sub-region, of which New Guinea is tl.e central mass, is comparatively poor in Mammalia, only 9 genera of marsupials being yet known, 6 of them being peculiar, with pig*, a few mice, and some deer (perhaps introduced) in the Moluccas. Birds are far more numerous, the Paradise birds and tho true crimson lories being peculiar to the sub-region, while more thnn 40 genera of land-birds are confined to it. It is exceptionally rich in peculiar forms of flycatchers, honey-suckers, kingfishers, cockatoos, and pigeons ; and its birds are generally characterized by a bril liancy of plumage far exceeding that which prevails in the sur rounding regions. The insects exhibit a similar brilliancy, some of the finest butterflies and beetles in the world belonging to this sub-region. Directly we pass east of the Solomon Islands we enter upon one of the poorest zoological regions in the world in proportion to its extent and luxuriant vegetation, the only exception to this poverty being in the land-shells, which are very largely developed and very peculiar. Indigenous Mammalia are wholly wanting. Birds are very scarce, no more than about 150 species being known from the numerous islands scattered over 5000 miles of the Pacific, while there are only about a dozen peculiar genera. Reptiles are more numerous than might be expected, considering the wide extent of ocean separating many of the islands. There are 1 4 genera of lizards, of which 6 are peculiar, but few extend eastward of the Samoa Islands, Snakes are much less abundant, and none are found east of the Fiji Islands. Insects are exceedingly scarce, and of little interest. The New Zealand group, though situated beyond the tropics and very remote from other lands, yet possesses a more ample and more interesting fauna. If we except two bats, mammals are wanting ; but birds are tolerably abundant, and are very peculiar and in teresting. There are 34 genera of land-birds, of which 16 are peculiar. Twelve of these are passerine birds, chiefly Mcliphagidce and Sturnidcc, with Nestor and Stringops, peculiar genera of parrots, and the extraordinary wingless Apteryx. Eeptiles are few. There are a few lizards, with one peculiar genus, but no snakes. Tha anomalous Hatteria has been already mentioned. There is also one frog belonging to a peculiar genus. There are some interesting fresh-water fishes, one genus belonging to the Salmonidce, a family Hot occurring elsewhere in the southern hemisphere ; and there aro several species allied to South American fishes. Insects are very few, and generally of small size and inconspi cuous colours. Many of them are peculiar, but they have mostly affinities with Australian groups, or with those from the Oriental

region.