The Tanghin, or Tanguen (T. venenifera), is the only plant of its genus, and is confined to Madagascar. It is described as a tree with smooth alternate leaves of moderate thickness, clustered towards the points of the branches, with large terminal cymes of flowers, having a salver-shaped corolla, with rose-coloured lobes. The ovary is twofold, with a long style and thick stigma; but usually only one attains to perfection, and forms an ellipsoid fruit, somewhat pointed at the ends, invested in a smooth purplish-green skin, and containing a hard stone surrounded by a thick fibrous pulp. The poisonous seed of the Tanghin is esteemed by the natives an infallible criterion of guilt or innocence. After being pounded, a small piece is swallowed by the supposed criminal. If he be cursed with a strong stomach, which retains the poison, he speedily dies, and is held guilty; if his feeble digestion rejects it, he necessarily escapes, and his innocence is considered proven.
Beneficent Nature has planted by the side of this fatal tree a species of infinite value, the Ravenala Madagascariensis, or “Traveller’s-Tree,” which derives the latter designation from the base of the petiole of its large leaves, expanded and hollowed out into a kind of gutter, being constantly filled with fresh water, and serving as a reservoir for the thirsty wayfarer. The Vacquois, or Vacoa (Pandanus utilis), one of the Screw-Pines, is of much utility to the natives, who fabricate sacks and bags out of its tenacious leaves. The manufacture of these bags is a source of comparative wealth for the poorer inhabitants of Madagascar, and to a still greater extent for those of Réunion and the Mauritius, whence they are exported annually by millions.
The Malagasy forests also include several resinous species; among others, the Copal-Tree, which furnishes the well-known gum used in Europe as a varnish; and the Vahea, a genus of Apocynaceæ, yielding caoutchouc, which will hereafter figure largely in the exports from this magnificent island. There are two species, namely, Vahea Madagascariensis—the “Voua Héri” of the natives—and Vahea gummifera. Numerous lianas, and a multitude of epiphytous plants, ferns, and orchids, envelop and intertangle the trunks of the great trees. I shall specify only the Beaded Liana (Abrus precatorius), whose small hard fruits, rounded and of a scarlet red, make graceful wreaths and necklaces; the Angræcum sesquipedale (an orchid), with bright irregular flowers; and the Angræcum fragrans, whose perfumed leaves supply a wholesome and savoury infusion. Finally, the Heritiera argentea, a tree about as large as our lindens, which certain botanists place among the Byttneriaceæ, and others among the Sterculiaceæ, is noticeable on account of its abundant foliage glittering silver-white.
CHAPTER IV.
VEGETABLE LIFE IN THE FORESTS OF THE NEW WORLD.
NATURE, said Linné, is admirable above all in the smallest things: Natura maxime miranda in minimis. He might, perhaps, have more justly said, Natura non minus miranda in minimis quam in maximis: Nature is not less wonderful in the least than in the greatest. Whether any created thing occupies a more or less considerable space, or contains a greater or lesser quantity of matter, is of no importance to the naturalist, who only studies the structure of the organs, the springs of life, and the different forces which set them in motion; and considered from this point of view, a vibrio[169] and an elephant, a penicillium and a baobab, possess for him the same importance, the same amount of interest. It would, however, be unjust not to recognize the fact that there is something very legitimate in the kind of reverential admiration which every man is conscious of in the presence of those things that symbolize, to a certain extent, power, strength, majesty, endurance—of those that possess in a high degree the two valuable qualities of force and greatness. Coleridge tells us that we admire the cataract because it is the type of power. Probably our feelings for the oak are connected with its emblematic properties of permanency, vigour, and durability. All the logic of logicians, and all the sentiment of natural philosophers, will never induce the mass of men to regard with the same interest an ant and a lion, a tuft of moss and a forest of oaks, a grain of sand and an Alpine peak. I do not think, therefore, that I am stooping to a merely vulgar prejudice in signalling out to the reader, among the vegetables of the forests, those whose exceptional dimensions and venerable antiquity are for every traveller an object of astonishment and curiosity. The truth is, that from their contemplation we derive a more vivid conception of Almighty Power than from the examination of even the most wonderful microscopical mechanism. To the still small voice of Nature our ears are deafened by the clash and clang of an ever-active world; but we cannot refuse to listen to the roar of the ocean or the reverberation of the thunder. As we move swiftly onward in the press of the crowd and the race of life, we ignore the tiny blade and the delicate organism beneath our feet; but our eyes must perforce be opened to the splendours of the sea, the undulating summits of snow-crowned mountains, the sapphire vault of the starry heavens. Those things realize to us, at once and with impressive force, the ubiquitous majesty of the Divine Builder. And it is well that they should lift us for a while above the materialism of our daily lives into a purer atmosphere of thought and feeling—should bid us, while still lingering in the dusty track, expand our souls to hear
“The mighty waters rolling evermore.”
It is not only in tropical regions that we meet with the giants of the vegetable world. Europe possesses a few of them; isolated, it is true, but comparable in their stature to the most robust denizens of the Torrid Zone: such are the chestnut-tree of Etna, and the plane of Boudjoukdéré, near Constantinople, of which so many travellers have spoken. The remains of the virgin forests of North America also abound in species analogous to our own, and capable of attaining, with an almost incalculable longevity, truly extraordinary proportions.
The lofty table-lands of California (the Rocky Mountains) nourish an entire tribe of gigantic Coniferæ, frequently assembled in immense forests. The Pinus Lambertiana, the Pinus Sabiniana, and the Pinus insignis, are not less than 160 to 180 feet in height; the Douglas Fir boasts of an almost equal stature, with a circumference which varies from 18 to 36 feet. Yet these colossal trees are surpassed by the Sequoia sempervirens, which is 240 to 260 feet high, and by the Titan of Titans, the huge Wellingtonia gigantea, which is also a Sequoia. I shall mention a few individuals of the latter species, whose dimensions may defy all comparison with the greatest trees of the Tropics.
According to Müller, about ninety-four of these Coniferæ flourish on a plateau of the Sierra Nevada, at an altitude of 5400 feet. They are distributed in small groups over a fertile soil. The gold-seekers have named one of them the “Miner’s Cabin.” Its trunk, 320 feet in height, presents an excavation 16 feet in width. The “Three Sisters” are individuals springing from one root; the “Old Bachelor,” stripped of its branches by successive hurricanes, stands in solitary desolation; the “Family” consists of two aged trees around which four-and-twenty scions have sprung up. The “Riding-School” is an enormous hollow trunk, prostrate on the ground, into which a man on horseback may enter as far as thirty yards. Another hollow trunk has been exhibited at San Francisco, where they have constructed out of it a saloon, adorned with tapestry and furniture, capable of accommodating forty persons.