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bark of large trees, sending out roots as they ascend which clasp around the trunk. Some mount straight up, others wind round the supporting trunks, and their large, handsome, and often highly-remarkable leaves, which spread out profusely all along the stem, render them one of the most striking forms of vegetation which adorn the damper and more luxuriant parts of the tropical forests of both hemispheres.
Screw-pines. These singular plants, constituting the family Pandavaceæ of botanists, are very abundant in many parts of the Eastern tropies, while they are comparatively scarce in America. They somewhat resemble Yuccas, but have larger leaves which grow in a close spiral screw on the stem. Some are large and palm-like, and it is a curious sight to stand under these and look up at the huge vegetable serew formed by the bases of the long drooping leaves. Some have slender-branched trunks, which send out aerial roots; others are stemless, consisting of an immense spiral cluster of stiff leaves ten or twelve feet long and only two or three inches wide. They abound most in sandy islands, while the larger species grow in swampy forests. Their large-clustered fruits, something like pineapples, are often of a red colour ; and their long stiff leaves are of great use for covering boxes and for many other domestic uses.
Orchids.—These interesting plants, so well known from the ardour with which they are cultivated on account of their beautiful and singular flowers, are preeminently tropical, and are probably more abundant in the mountains of the equatorial zone than in any other region. Ilere they are almost omnipresent in some of their countless forms. They grow on the stems, in the
general in the forests of extra-tropical countries, is probably dependent on the extreme equability and permanence of the climate. Atmospheric conditions are much more important to the growth of plants than any others. Their severest struggle for existence is against climate. Is we approach towards regions of polar cold or desert aridity the variety of groups and species regularly diminishes; more and more are unable to sustain the extreme climatal conditions, till at last we find only a few specially organized forms which are able to maintain tbeir existence. In the extreme north, pive or birch trees; in the desert, a few palms and prickly shrubs or aromatic herbs alone survive. In the equalle equatorial zone there is no such struggle against climate. Erery form of vegetation has become alike adapted to its genial heat and ample moisture, which has probably changed little even throughout geological periods ; and the never-ccasing struggle for existence between the various species in the same area has resulted in a nice balance of organic forces, which gives the advantage, now to one, now to another, species, and prevents any one type of vegetation from monopolising territory to the exclusion of the rest. The same general causes have led to the filling up of every place in nature with some specially adapted form. Thus we find a forest of smaller trees adapted to grow in the shade of greater trees. Thus we find every tree supporting numerous other forms of vegetation, and some so crowded with epiphytes of various kinds that their forks and horizontal branches are veritable gardens. Creeping ferns and arums run up the smoothest trunks; an immense variety of climbers lang in tangled masses from the branches and mount over
than mosses, while the large Grammatophyllums of Borneo, which grow in the forks of trees, form a mass of leafy stems ten feet long, and some of the terrestrial species—as the American Sobralias-grow erect to an equal height. The fleshy aerial roots of most species give them a very peculiar aspect, as they often grow to a great length in the open air, spread over the surface of rocks, or attach themselves loosely to the bark of trees, extracting nourishment from the rain and from the aqueous vapour of the atmosphere. Yet notwithstanding the abundance and variety of orchids in the cquatorial forests they seldom produce much effect by their flowers. This is due partly to the very large proportion of the species having quite inconspicuous flowers; and partly to the fact that the flowering season for each kind lasts but a few weeks, while different species flower almost every month in the year. It is also due to the manner of growth of orchids, generally in single plants or clumps which are seldom large or conspicuous as compared with the great mass of vegetation around them. It is only at long intervals that the traveller mects with anything which recalls the splendour of our orchid-houses and flower-shows. The slender-stalked golden Oncidiums of the flooded forests of the Upper Amazon; the grand Cattleyas of the drier forests; the Clogynes of the swamps, and the remarkable Vundu lowii of the bill forests of Borneo, are the chief examples of orchidbeauty that have impressed themselves on the memory of the present writer during twelve years' wandering in tropical forests. The last-named plant is unique among orchids, its comparatively small cluster of leaves sending out numerous flower-stems, which hang down
like cords to a length of eight feet, and are covered with numbers of large star-like crimson-spotted flowers.
Bamboos.-The gigantic grasses called bamboos can hardly be classed as typical plants of the tropical zone, because they appear to be absent from the entire African continent and are comparatively scarce in South America. They also extend beyond the geographical tropics in China and Japan as well as in Northern India. It is however within the tropics and towards the equator that they attain their full size and beauty, and it is here that the species are most numerous and offer that variety of form, size, and quality, which renders them so admirable a boon to man. A fine clump of large bamboos is perhaps the most graceful of all vegetable forms, resembling the light and airy plumes of the birdof-paradise copied on a gigantic scale in living foliage. Such clumps are often eighty or a hundred feet bigh, the glossy stems, perhaps six inches thick at the base, springing up at first straight as an arrow, tapering gradually to a slender point, and bending over in elegant curves with the weight of the slender branches and grassy leaves. The various species differ greatly in size and proportions ; in the comparative length of the joints; in the thickness and strength of the stem-walls; in their straightness, smoothness, hardness, and durability. Some are spiny, others are unarmed; some have simple stems, others are thickly set with branches; while some species even grow in such an irregular, zig-zag, branched manner as to form veritable climbing bamboos. They generally prefer dry and upland stations, though some grow near the banks of rivers, and a few in the thick forests and, in South America, in Hooded tracts. They often form dense
thickets where the forests have been cleared away ; and, owing to their great utility, they are cultivated or preserved near native houses and villages, and in such situations often give a finishing charm to the landscape.
Uses of the Bamboo. Perhaps more than any other single type of vegetation, the bamboo seems specially adapted for the use of half-civilized man in a wild tropical country ; and the purposes to which it is applied are almost endless. It is a natural column or cylinder, very straight, uniform in thickness, of a compact and solid texture, and with a smooth flinty:naturally-polished external skin. It is divided into ringed joints at zgular intervals which correspond to septa or partitions within, so that each joint forms a perfectly closed and air-tight vessel. Owing to its hollowness, the hardness of the external skin, and the existence of the joints and partitions, it is wonderfully strong in proportion to its weight. It can be found of many distinct sizes and proportions; light or heavy, long or short jointed, and varying from the size of a reed to that of a tall and slender palm-tree. It can be split with great facility and accuracy; and, owing to its being hollow, it can be easily cut across or notched with a sharp knife or hatchet. It is excessively strong and highly elastic, and whether green or dry is almost entirely free from any peculiar taste or smell. The way in which these various qualities of the bamboo render it so valuable, will be best shown by giving a brief account of some of the uses to which it is applied in the Malay Archipelago.
Several effective weapons are easily made from bamboo. By cutting off the end very obliquely just beyond a joint, a very sharp cutting point is produced