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much of it unsuited to agriculture, although vast areas are more or less adapted to grazing, which at present in much of the commonwealth is the most important industry. There is a more or less marked wet and dry season in most of Australia, as on our own Pacific coast. In the south most of the rain falls during the winter months, May to September; in the north the heaviest rains fall in the summer. June is the wettest month in the south, January

in the north.

Northern Australia, lying entirely within the tropics, has for the most part a genuinely tropical climate, hot and humid in the coastal districts. In the more elevated regions of the plateau, however, there may be sharp frost during the winter months, June to August. In August of last year I observed bananas and other tender plants cut down by frost at an elevation of 2,000 to 3,000 feet, in latitude 17°. On the coast, however, frost is quite unknown, and the forest shows a genuine tropical luxuriance.

The wettest region in Australia is in northeast Queensland, on the coast, about latitude 17°. In this region a short range of precipitous mountains rises directly from the coast to a height of over 5,000 feet, the highest land in the state. At the foot of this range, the precipitation is very heavy. One place, Babinda, which I visited in August, 1921, had already registered over two hundred inches for the year, and it rained almost incessantly during my stay.

The low swampy forest about Babinda was almost impenetrable, the trees loaded down with creepers of various kinds, among which the rattan palms were only too conspicuous. Throughout the eastern tropics the thickets of rattans are a great hindrance to progress in the forest, as their tough, horribly spiny twining stems make absolutely impenetrable tangles, natural barbed-wire barriers. Climbing Aroids and species of Vitis and Piper are also abundant as well as various other lianas.

In these wet lowland jungles, the palms reach their fullest development, forming a conspicuous and beautiful feature of the vegetation. One of the commonest and most attractive species is Archontophoenix Cunninghamiana, often cultivated under the name Seaforthia elegans, and one of the most beautiful of all palms, with its smooth slender trunk and crown of graceful feathery leaves. No feature of the Australian vegetation is more beautiful than the groves of these lovely palms.

Screw-pines (Pandanus) abound in this region and there are also a number of species of Cycads. Australia is especially rich in these ancient plants. The most widespread genus is Macrozamia, of which there are several species, the genus having representatives in all the states. The two other Australian genera, Cycas and

[graphic]

FIG. 1. TROPICAL RAIN-FOREST, NORTH QUEENSLAND

Bowenia, are confined to tropical Queensland. The latter genus, peculiar to Australia, differs much in appearance from any living Cycads, in its solitary bi-pinnate leaves, rather suggesting a bracken fern.

In the dryer parts of the Queensland coast the rain-forest is replaced by a more or less mixed forest, composed in part of Eucalyptus, and in part of tropical rain-forest types, like Ficus. A forest of this type may be seen occupying the sandy soil in the neighborhood of Cairns, the principal port of North Queensland.

A feature of the coast in this district is the mangrove formation along the shore and the banks of the streams flowing into the sea. Several genera are represented, the most important being the widespread Rhizophora and Avicennia.

Some interesting ferns were noted in this region, the most striking being a gigantic Angiopteris which was seen in several places in the vicinity of Babinda.

Immediately back of the coast the land rises rapidly to a plateau reaching an extreme elevation of about 4,000 feet, but averaging 2,000 to 3,000 feet over most of its extent.

This table-land has an ample rainfall, and on the better soils develops a fine forest which yields extremely valuable timber. Much of the timber has been destroyed, but there are still some remnants which are accessible, and these are really magnificent examples of tropical forest growth. This tropical rain-forest is known in Queensland by the very inappropriate name of "Scrub" and is confined to the rich basaltic and alluvial soils.

The trees of this forest are mainly of Malayan affinity, and are tall with lofty straight trunks yielding a large amount of fine timber. Some of them, especially the Kauri (Agathis Palmerstoni) and "Red Cedar" (Cedrela toona) reach a very large size. The latter was formerly abundant and sometimes attained a diameter of upwards of ten feet. It has been largely exterminated, but an occasional fine specimen may still be seen, and the same is true of the Kauri.

Belonging to the same family (Meliaceae) as the cedar are several species of Flindersia, which are locally known as "hickory," "maple," "beech," and other woods not in the least related to them. Other characteristic trees are Elaeocarpus, (Tiliaceae), Aleurites Moluccana, widespread throughout Polynesia; Sideroxylon (Sapotaceae), Eugenia (Myrtaceae) and others. The characteristic Australian family Proteaceae is represented in the rainforest by several species of Grevillea, Stenocarpus, Macadamia and other genera. Grevillea robusta of southern Queensland is often grown in California as an ornamental tree.

This upland forest has much finer trees than the lowland forest

[graphic]

FIG. 2.

TRUNK OF GIANT FIG, NEAR YUNGABURRA, NORTH QUEENSLAND

near the coast, but the palms and some other tropical types are almost entirely absent, and the development of the epiphytes and lianas is not so marked, although these are by no means absent. Many of the large trees, as is so common in rain-forests everywhere, show a conspicuous development of buttresses at the base of the trunk.

The giants of the forest are species of Ficus, the size of which is amazing. As in most tropical lands the genus is well represented in northern Australia, some species extending as far south as Sydney. Like so many other species of Ficus, these giant Queensland figs begin life as epiphytes, the descending roots finally coalescing more or less completely, and strangling the host tree. The descending roots are produced in great numbers and in one tree that was seen, the huge conical trunk formed by the united roots was said to measure 120 feet in circumference at the ground, and the enormous spreading crown was in proportion.

While the predominant forest on the plateau is "scrub," there are large areas occupied almost exclusively by open Eucalyptus forest. This Eucalyptus forest is the dominant type of vegetation over much of Australia, but in the region in question is restricted to areas of sandy soil. The line between the "scrub" and the Eucalyptus forest is often very sharply marked, and is probably determined by the difference in the soil.

In southern Queensland, in the neighborhood of Brisbane, the Eucalyptus forest predominates, though there are also areas occupied by "scrub," but many of the strictly tropical species of North Queensland are absent.

Probably the most striking tree of South Queensland is the "Bunya" (Araucaria Bidwilli) a coniferous tree confined to a relatively small area in this region. It reaches a large size, and is valuable for its timber. The big seeds were much prized as food by the aboriginals. This handsome tree is frequently cultivated in California, where it seems very much at home. A second species, A. Cunninghamii, is much more widely diffused, and was seen in extensive pure stands on some of the islands off the coast of Queensland.

An analysis of the constituents of the scrub vegetation of Queensland and New South Wales shows that it is largely made up of genera widespread through the Indo-Malayan region, or closely related to these, and may very properly be considered a part of the great Malayan flora. Such types as the figs, palms, screw-pines, Araceae, many epiphytic ferns and orchids are characteristic of the whole Indo-Malayan region; and as it is evident that northeast Australia was connected at no very distant period with the great island of New Guinea, it is pretty certain that this portion of the Australian flora is derived from the north.

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