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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. 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. 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. The comparatively few indigenous placental mammals, besides the See also:dingo or wild 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. 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. 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.
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. The See also:black See also:swan was thought remarkable when discovered, as belying an old Latin See also:proverb. 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. 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. 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. Frogs of many kinds are plentiful, the brilliant See also:green frogs being especially conspicuous and noisy. Australia is See also:rich in snakes, and has more than a See also:hundred different kinds. Most of these are venomous, but all are not equally dreaded. 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. 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. 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. 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. Physical surroundings rather than See also:latitude deter-mine the See also:character of the flora. The See also:contour lines showing the heights above sea-level are the directions along which species spread to form zones. 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. 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. 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:Baker and See also: Jarrah . I.12 Grey iron-bark . 1.18 Red iron-bark . . I.22 Forest oak . I.2I Tallow wood . 1.23 Mahogany . 120 Grey gum . '917 Red gum . • '995 European Specific timber. gravity. Ash . '753 Beech. •690 See also:Chestnut . '535 See also:British oak '99 The resistance to breaking or rupture of Australian timber is very high; grey iron-bark with a specific gravity of 1.18 has a modulus of rupture of 17,900 lb per sq. in. compared with I1,800 lb for British oak with a specific gravity of •69 to •99. No Australian timber in the foregoing See also:list has a less modulus than 13,100 lb per sq. in. Various " scrubs " characterize the interior, differing very widely from the coastal scrubs. " Mallee " scrub occupies large tracts of South Australia and Victoria, covering probably an extent of 16,000 sq. m. The mallee is a species of eucalyptus growing 12 to 14 ft. high. The tree breaks into thin stems See also:close to the ground, and these See also:branch again and again, the leaves being developed See also:umbrella-See also:fashion on the See also:outer branches. The mallee scrub appears like a forest of dried See also:osier, growing so close that it is not always easy to ride through it. Hardly a See also:leaf is visible to the height of one's head; but above, a See also:crown of thick See also:leather-like leaves shuts out the sunlight. The ground below is perfectly See also:bare, and there is no water. Nothing could add to the sterility and the monotony of these mallee scrubs. Mulga " scrub is a somewhat similar thicket, covering large areas. The tree in this instance is one of the acacias, a genus distributed through all parts of the continent. Some species have rather elegant blossoms, known to the settlers as " wattle." They serve admirably to break the sombre and monotonous aspect of the Australian vegetation. Two species of See also:acacia are remarkable for the delicate and See also:violet-like perfume of their wood—myall and yarran. The majority of the species of Acacia are edible and serve as reserve See also:fodder for See also:sheep and See also:cattle. In the alluvial portions of the interior salsolaceous plants—saltbush, bluebush, cottonbush—are invaluable to the pastoralist, and to their presence the pre-See also:eminence of Australia as a See also:wool-producing country is largely due. See also:Grasses and herbage in great variety constitute the most valuable element of Australian flora from the commercial point of view. The herbage for the most part grows with marvellous rapidity after a See also:spring or autumn shower and forms a natural shelter for the more See also:stable growth of nutritious grasses. Under the See also:system of grazing practised throughout Australia it is customary to allow sheep, cattle and horses to run at large all the year round within enormous enclosures and to depend entirely upon the natural growth of grass for their subsistence. Proteaceous plants, although not exclusively Australian, are exceedingly characteristic of Australian scenery, and are counted amongst the See also:oldest flowering plants of the world. The order is easily distinguished by the hard, dry, woody texture of the leaves and the dehiscent fruits. They are found in New Zealand and also in New See also:Caledonia, their greatest developments being on the south-west of the Australian continent. Proteaceae are found also in Tierra del Fuego and See also:Chile. They are also abundant in South Africa, where the order forms the most conspicuous feature of vegetation. The range in species is very limited, no one being common to eastern and western Australia. The See also:chief genera are See also:banksia (See also:honeysuckle), and hakea (See also:needle bush). The Moreton See also:Bay pine (See also:Araucaria Cunninghamii) is reckoned amongst the giants of the forest. The genus is associated with one long extinct in Europe. Moreton Bay pine is chiefly known by the utility of its wood. Another species, A. Bidwillii, or the bunyabunya, afforded food in its See also:nut-like seeds to the See also:aborigines. A most remarkable form of vegetation in the north-west is the gouty-stemmed tree (Adansonia Gregorii), one of the See also:Malvaceae. It is related closely to the famous See also:baobab of tropical Africa. The " grass-tree " (Xanthorrhoea), of the uplands and coast regions, is peculiarly Australian in its aspect. It is seen as a See also:clump of See also:wire-like leaves, a few feet in See also:diameter, surrounding a See also:stem, hardly thicker than a walking-stick, rising to a height of to or 12 ft. This terminates in a long spike thickly studded with white blossoms. The grass-tree gives as distinct a character to an Australian picture as the See also:agave and See also:cactus do to the Mexican landscape. With these might be associated the gigantic See also:lily of Queensland (Nymphaea gigantea), the leaves of which See also:float on water, and are quite 18 in. across. There is also a gigantic lily (Doryanthes excelsa) which grows to a height of 15 feet. The " See also:flame tree is a most conspicuous feature of an Illawarra landscape, the largest racemes of crimson red suggesting the name. The949 waratah or native See also:tulip, the magnificent flowering head of which, with the kangaroo, is symbolic of the country, is one of the Proteaceae. The natives were accustomed to suck its tubular See also:flowers for the honey they contained. The " nardoo " See also:seed, on which the aborigines sometimes contrived to exist, is a creeping plant, growing plentifully in swamps and shallow pools, and belongs to the natural order of Marsileaceae. The spore-cases remain after the plant is dried up and withered. These are collected by the natives, and are known over most of the continent as nardoo. No See also:speculation of hypothesis has been propounded to See also:account satisfactorily for the origin of the Australian flora. As a step towards such hypothesis it has been noted that the Antarctic, the South African, and the Australian floras have many types in common. There is also to a limited extent a European element present. One thing is certain, that there is in Australia a flora that is a remnant of a vegetation once widely distributed. Heer has described such Australian genera as Banksia, Eucalyptus, Grevillea and Hakea from the See also:Miocene of See also:Switzerland. Another point agreed upon is that the Australian flora is one of vast antiquity. There are genera so far removed from every living genus that many connecting links must have become extinct. The region extending round the south-western extremity of the continent has a peculiarly characteristic assemblage of typical Australian forms, notably a great abundance of the Proteaceae. This flora, isolated by arid country from the See also:rest of the continent, has evidently derived its plant life from an outside source, probably from lands no longer existing. Additional information and CommentsThere are no comments yet for this article.
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