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See also:FAUNA AND See also:FLORA] See also:highlands . In summer the See also:sun has See also:great See also:power, and the temperature reaches oo° in the shade, with hot winds blowing from the interior . The See also:weather on the whole is remarkably dry . At See also:Adelaide there are on an See also:average 120 See also:rainy days per annum, with a mean rainfall of 2o•88 in . The See also:country is naturally very healthful, as See also:evidence of which may be mentioned that no great epidemic has ever visited the See also:state . Western See also:Australia has practically only two seasons, the See also:winter or wet See also:season, which commences in See also:April and ends in See also:October, and Western the summer or dry season, which comprises the See also:remainder Australia. of the See also:year . During the wet season frequent and heavy rains fall, and thunderstorms, with See also:sharp showers, occur in the summer, especially on the See also:north-See also:west See also:coast, which is some-times visited by hurricanes of great violence . In the See also:southern and See also:early-settled parts of the state the mean temperature is about 64°, but in the more See also:northern portions the See also:heat is excessive, though the dryness of the See also:atmosphere makes it preferable to moist tropical climates . The average rainfall at See also:Perth is 33 in. per annum . The See also:climate of the Northern Territory is extremely hot, except on the elevated tablelands; altogether, the temperature of this See also:part of the See also:continent is very similar to that of northern See also:Queensland, and the climate is not favourable to Europeans . The rainfall in the extreme north, especially in See also:January and See also:February, is very heavy, and the See also:annual average along the coast is about 63 in . The whole of the See also:peninsula north of 15° S. has a rainfall considerably exceeding 4o in . This region is backed by a See also:belt of about See also:loo m. wide, in which the rainfall is from 30 to 40 in., from which inwards the rainfall gradually declines until between Central See also:Mount See also:Stuart and See also:Macdonnell ranges it falls to between 5 and to in . See also:Fauna and Flora.—The origin of the fauna and flora of Australia has attracted considerable See also:attention . Much accumulated evidence, biological and See also:geological, has pointed to a southern See also:extension of See also:India, an eastern extension of See also:South See also:Africa, and a western extension of Australia into the See also:Indian Ocean . The See also:comparative richness of proteaceous See also:plants in Western Australia and South Africa first suggested a See also:common source for these See also:primitive types . Dr H . O . See also:Forbes See also:drew attention to a certain community amongst birds and other vertebrates, invertebrates, and amongst plants, on all the lands stretching towards the south See also:pole . A theory 'was therefore propounded that these known types were all derived from a continent which has been named Antarctica . The supposed continent extended across the south pole, practically joining Australia and South See also:America . Just as we have evidence of a former mild climate in the See also:arctic regions, so a similar mild climate has been postulated for Antarctica . See also:Modern naturalists consider that many of the problems of Australia's remarkable fauna and flora can be best explained by the following See also:hypothesis:—The region now covered by the See also:antarctic See also:ice-cap was in early See also:Tertiary times favoured by a mild climate; here See also:lay an antarctic continent or See also:archipelago . From an See also:area corresponding to what is now South America there entered a fauna and flora, which, after undergoing modification, passed by way of See also:Tasmania to Australia . These immigrants then See also:developed, with some exceptions, into the See also:present Australian flora and fauna . This theory has advanced from the position of a disparaged See also:heresy to See also:acceptance by leading thinkers . The See also:discovery as fossil, in South America, of primitive or ancestral forms of marsupials has given it much support . One of these, Prothylacinus, is regarded as the forerunner of the marsupial See also:wolf of Tasmania . An interesting See also:link between divergent marsupial families, still living in See also:Ecuador, the Coenolestes, is another discovery of See also:recent years . On the Australian See also:side the fact that Tasmania is richest in marsupial types indicates the See also:gate by which they entered . It is not to be supposed that this antarctic See also:element, to which See also:Professor See also:Tate has applied the name Euronotian, entered a See also:desert barren of all See also:life . Previous to its arrival Australia doubtless possessed considerable vegetation and a scanty fauna, chiefly invertebrate . At a comparatively recent date Australia received its third and newest constituent . The islands of Torres Strait have been shown to be the denuded remnant of a former extension of Cape See also:York peninsula in North Queensland . Previous to the existence of the strait, and across its site, there poured into Australia a See also:wealth of Papuan forms . Along the Pacific slope of the Queensland See also:Cordillera these found in See also:soil and climate a congenial See also:home .
Among the plants the See also:wild See also:banana, See also:pepper, See also:orange and See also:mangosteen, See also:rhododendron, epiphytic See also:orchids and the See also:palm; among mammals the bats and947
rats; among birds the See also:cassowary and See also:rifle birds; and among See also:reptiles the See also:crocodile and See also:tree See also:snakes, characterize this element
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The numerous facts, geological, See also:geographical and biological, which when linked together lend great support to this theory, have been well worked out in Australia by Mr See also: He showed that not only as regards beasts, but also as regards birds, these regions are thus sharply limited . Australia, he pointed out, has no woodpeckers and no pheasants, which are widely-spread Indian birds . Instead of these it has See also:mound-making turkeys, See also:honey-suckers, cockatoos and See also:brush-tongued lories, all of which are found nowhere else in the See also:world . The marsupials constitute two-thirds of all the Australian See also:species of mammals . It is the well-known peculiarity of this See also:order that the See also:female has a pouch or See also:fold of skin upon her See also:abdomen, in which she can See also:place the young for suckling within reach of her teats . The See also:opossum of America is the only species out of See also:Australasia which is thus provided . Australia is inhabited by at least 1 Io different species of marsupials, which is about two-thirds of the known species; these have been arranged in five tribes, according to the See also:food they eat, viz., the grass-eaters (kangaroos), the See also:root-eaters (wombats), the See also:insect-eaters (bandicoots), the flesh-eaters (native See also:cats and rats), and the See also:fruit-eaters (phalangers) . The See also:kangaroo (Macropus) lives in droves in the open grassy plains . Several smaller forms of the same See also:general See also:appearance are known as wallabies, and are common everywhere . The kangaroo and most of its congeners show an extraordinary disproportion of the See also:hind limbs to the fore part of the See also:body . The See also:rock wallabies again have See also:short tarsi of the hind legs, with a See also:long pliable tail for climbing, like that of the tree kangaroo of New See also:Guinea, or that of the See also:jerboa . Of the larger kangaroos, which attain a See also:weight of 200 lb and more, eight species are named, only one of which is found in Western Australia . Fossil bones of See also:extinct kangaroo species are met with; these kangaroos must have been of enormous See also:size, twice or thrice that of any species now living . There are some twenty smaller species in Australia and Tasmania, besides the rock wallabies and the See also:hare kangaroos; these last are wonderfully See also:swift, making clear jumps 8 or to ft. high . Other terrestrial marsupials are the See also:wombat (Phascolomys), a large, clumsy, burrowing animal, not unlike a See also:pig, which attains a weight of from 6o to too lb; the See also:bandicoot (Perameles), a See also:rat-like creature whose depredations See also:annoy the agriculturist; the native See also:cat (Dasxurus), noted robber of the poultry yard; the Tasmanian wolf (Thylacinus), which preys on large See also:game; and the recently discovered Notoryctes, a small animal which burrows like a See also:mole in the desert of the interior . Arboreal species include the well-known opossums (See also:Phalanger) ; the extraordinary tree-kangaroo of the Queensland tropics; the flying See also:squirrel, which expands a membrane between the legs and arms, and by its aid makes long sailing jumps from tree to tree; and the native See also:bear (Phascolarctos), an animal with no See also:affinities to the bear, and having a long soft See also:fur and no tail . The Myrmecobius of Western Australia is a bushy-tailed See also:ant-eater about the size of a squirrel, and from its lineage and structure of more than passing See also:interest . It is, See also:Mivart remarks, a survival of a very See also:ancient state of things . It had ancestors in a flourishing See also:condition during the Secondary See also:epoch . Its congeners even then lived in See also:England, as is proved by the fact that their See also:relics have been found in the Stonesfield oolitic rocks, the deposition of which is separated from that which gave rise to the See also:Paris Tertiary strata by an See also:abyss of past See also:time which we cannot venture to See also:express even in thousands of years . We pass on to the other curious order of non-placental mammals,' that of the Monotremata, so called from the structure of their See also:organs of evacuation with a single orifice, as in birds . Their abdominal bones are like those of the marsupials; and they are furnished with pouches for their young, but have no teats, the See also:milk being distilled into their pouches from the mammary glands . Australia and Tasmania possess two animals of this order—the See also:echidna, or spiny 948 ant-eater (hairy in Tasmania), and the See also:Platypus anatinus, the See also:duck-billed water mole, otherwise named the Ornithorhynchus paradoxus . This See also:odd animal is provided with a See also:bill or See also:beak, which is not, like that of a See also:bird, affixed to the See also:skeleton, but is merely attached to the skin and muscles .
Australia has no apes, monkeys or baboons, and no ruminant beasts
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The comparatively few indigenous placental mammals, besides the See also:dingo or wild See also:dog—which, however, may have come from the islands north of this continent—are of the See also:bat tribe and of the rodent or rat tribe
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There are four species of large fruit-eating bats, called flying foxes, twenty of insect-eating bats, above twenty of See also:land-rats, and five of water-rats
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The See also:sea produces three different See also:seals, which often ascend See also:rivers from the coast, and can live in lagoons of fresh water; many cetaceans, besides the " right See also:whale " and sperm whale; and the See also:dugong, found on the northern shores, which yields a valuable medicinal oil
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The birds of Australia in their number and variety of species may be deemed some See also:compensation for its poverty of mammals; yet it will not stand comparison in this respect with regions of Africa and South America in the same latitudes
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The See also:black See also:swan was thought remarkable when discovered, as belying an old Latin See also:proverb
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There is also a See also: The honey-eaters present a great diversity of plumage . There are also many kinds of game birds, pigeons, ducks, geese, plovers and quails . The See also:ornithology of New South See also:Wales and Queensland is more varied and interesting than that of the other provinces . As for reptiles, Australia has a few tortoises, all of one See also:family, and not of great size . The " leathery turtle," which is herbivorous, and yields abundance of oil, has been caught at sea off the See also:Illawarra coast so large as 9 ft. in length . The saurians or lizards are numerous, chiefly on dry sandy or rocky ground in the tropical region . The great crocodile of Queensland has been known to attain a length of 30 ft.; there is a smaller one about 6 ft. in length to be met with in the shallow lagoons of the interior of the Northern Territory . Lizards occur in great profusion and variety . The See also:monitor, or See also:fork-tongued See also:lizard, which burrows in the See also:earth, climbs and swims, is said to grow to a length of 8 to 9 ft . This species and many others do not extend to Tasmania . The monitor is popularly known as the goanna, a name derived from the See also:iguana, an entirely different animal . There are about twenty kinds of See also:night-lizards, and many which hibernate .
One species can utter a cry when pained or alarmed, and the tall-See also:standing frilled lizard can lift its forelegs, and squat or See also:hop like a kangaroo
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There is also the See also:Moloch horridus of South and Western Australia, covered with tubercles bearing large spines, which give it a very See also:strange aspect
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This and some other lizards have power to See also:change their See also:colour, not only from See also:light to dark, but over some portions of their bodies, from yellow to See also:grey or red
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Frogs of many kinds are plentiful, the brilliant See also:green frogs being especially conspicuous and noisy
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Australia is See also:rich in snakes, and has more than a See also:hundred different kinds
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Most of these are venomous, but all are not equally dreaded
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Five rather common species are certainly deadly—the See also:death See also:adder, the See also:
The Australian seas are inhabited by many fishes of the same genera as exist in the southern parts of See also:Asia and Africa
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Of those peculiar to Australian waters may be mentioned the arripis, represented by what is called among the colonists a See also:salmon See also:trout
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A very See also:fine fresh-water See also:fish is the See also: Two existing fishes may be mentioned as ranking in interest with the Myrmecobius (ant-eater) in the eyes of the naturalist . These are the Ceratodus Forsteri and the Port Jackson See also:shark . The " mud-fish " of Queensland (Ceratodus Forsteri) belongs to an ancient order of fishes—the Dipnoi, only a few species of which have survived from past geological periods . The Dipnoi show a distinct transition between fishes and See also:amphibia . So far the mud-fish has been found only in the See also:Mary and the See also:Burnett rivers . Hardly of less scientific interest is the Port Jackson shark (Heterodonius) . It is a harmless helmeted ground-shark, living on molluscs, and almost the See also:sole survivor of a genus abundant in the Secondary rocks of See also:Europe . The eastern parts of Australia are very much richer both in their See also:botany and in their zoology than any of the other parts . This is due in part to the different See also:physical conditions there prevail- Flora. See also:ing and in part to the invasion of the north-eastern portion of the continent by a number of plants characteristically Melanesian . This element was introduced via Torres Strait, and spread down the Queensland coast to portions of the New South Wales littoral, and also See also:round the Gulf of See also:Carpentaria, but has never been able to obtain a hold in the more arid interior . It has so completely obliterated the See also:original flora, that a Queensland coast See also:jungle is almost an exact replication of what may be seen on the opposite shores of the straits, in New Guinea . This wealth of plant life is confined to the littoral and the coastal valleys, but the central valleys and the plateaux have, if not a varied flora, a considerable wealth of See also:timber trees in every way See also:superior to the flora inland in the same latitudes .
In the interior there is little change in the general aspect of the vegetation, from the Australian See also:Bight to the region of Carpentaria, where the See also:exotic element begins
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Behind the luxuriant jungles of the sub-tropical coast, once over the See also:main range, we find the purely Australian flora with its apparent sameness and sombre dulness
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Physical surroundings rather than See also:latitude deter-mine the See also:character of the flora
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The See also:contour lines showing the heights above sea-level are the directions along which species spread to form zones
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Putting aside the exotic vegetation of the north and See also:east coast-line, the Australian See also:bush gains its peculiar character from the prevalence of the so-called See also:gum-trees (See also:Eucalyptus) and the acacias, of which last there are 300 species, but the eucalypts above all are everywhere
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Dwarfed eucalypts fringe the tree-limit on Mount See also:Kosciusco, and the soakages in the parched interior are indicated by a line of the same trees, stunted and straggling
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Over the vast continent from See also: As early as 1866, tannic See also:acid, gallic acid, See also:wood spirit, acetic acid, essential oil and eucalyptol were produced from various species of eucalyptus, and researches made by Australian chemists, notably by Messrs . See also: |