- Study the zonal map in the Atlas and name the natural zones
of Australia.
- Which zone occupies the greatest area?
Peculiarities of Vegetable and Animal Life. Its long isolation has led to the development in Australia of a peculiar plant and animal
life.
Fig. 192. An echidna.
Most of its plants are quite different from those in other parts ot the world. The most typical Australian trees are the acacia and eucalyptus of which there are many varieties. The eucalyptus grows very rapidly, sometimes reaching a height of from 100 to 150 metres. Its wood is hard and it has deep roots through which it sucks in the underground moisture. On most of these trees the leaves hang edgewise to the sun giving little shade. From them eucalyptus oil is made. Side by side with these giants grow dwarfish '.l like eucalypts. Several species of this tree have been brought to Hie Soviet Union, where they are successfully grown on the Black Sea coast of the Caucasus and planted to drain marshlands.
The tree-fern is widespread in the wetter regions of Australia.
The animal life is also very peculiar. Many primitive forms survive that are long extinct in other parts of the world. There are animals that suckle their young but lay eggs like birds. Such are the echidna of the semideserts and the duckbill of south-eastern Australia (Figs. 192, 193).
Fig 193. Duckbills
There is a great variety of marsupials, animals carry ing their tiny young (called 'joeys') in pouches on their bellies. Especially numerous among these are various kangaroos, some of them two metres high (Fig. 194). Ordinary mammals are few. Most notable among these is the dingo, or wild dog, considered a most dangerous beast in these parts.
Among the birds are the emu, a stump-winged ostrich, and the lyrebird (Fig. 195). These are found only in Australia. In the tropical forests of northern Australia there are cassowaries and bright-plumed birds of paradise. There is a great variety of parrots, including white and black cockatoos and others. There are myriads of mosquitos gnats, flies and other insects that pester both man and beast.
Australia formerly had neither cultured plants nor domestic animals of its own. The present denizens were brought from Europe. The chief animals bred today are sheep, flocks of which are often attacked by dingoes. The rabbit was also introduced into Australia from Europe, and so numerous is it now that it has become a pest. Thousands of kilometres of barbed wire fences have been erected to keep it from spreading, but without avail. Today the rabbit is hunted for its fur and meat.
Natural Zones. Forests are few in Australia. Open deserts and stretches of bush cover the greater part of the continent.
Fig. 194. A kangaroo in the Australian savannah.
Isolated strips of tropical rain forest occur along the north and north-east coasts, where the rainfall is heavier (Fig. 196).
In the drier regions grow thin forests of enormous eucaly pts', which are usually surrounded by thick carpets of grass.
As the rainfall decreases towards the interior in the northern and eastern part of the continent, these forests merge into savannahs with tall grass that withers in the dry period (Fig. 194). Amidst the grass stand trees here and there: eucalypts and acacias. Bottle-trees occur that have swollen trunksforstoringwater.
The dry undrained interior is a semidesert and sandy or stony desert region.
For hundreds of kilometres in the semideserts stretch closely interlaced and impenetrable thickets of cheerless, dark-grey bushes, dry and prickly. They consist mainly of stunted and prickly acacia in the north and eucalyptus shrub in the south. These areas are called the scrub in Australia.
Desert vegetation is very poor, consisting merely of bunches of prickly grass, with blades as sharp as knives.
In the damp south-east are dense subtropical forests consisting of evergreen eucalypts, lianas and tree-ferns. They extend to Tasmania, where the southern beech is widespread.
In the south-west of Australia grow eucalypts and other large trees. There is almost no palm, liana or fern in these regions. In the underbrush grow grass-trees with low, thick trunks and long bunches of leaves. Evergreen shrubs are very numerous.
Questions and Assignments.
1. Compare the zonal and climate maps and point out the climatic peculiarities of the tropical forests, savannahs, deserts and subtropics.
1 Most of the Australian trees are hardwoods of a kind known as eucalypts, which belong to the Saaily of trees called Eucalyptus.
