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amongst which a very English-looking bramble,' bearing a good yellow fruit, is the first to mark the change ; next, mighty oaks, with large lamellated cups and magnificent foliage succeed, till along the ridge of the mountain to Kursiong, at an elevation of about 4800 feet, the change in the flora is complete. Here the vegetation recalls to mind home impressions: the oak flowering, the birch bursting into leaf, the violet, Chrysosplenium, Stellaria and Arum, Vaccinium, wild strawberry, maple, geranium, bramble. A colder wind blew here; mosses and lichens carpeted the banks and road-sides; the birds and insects were very different from those below, and everything proclaimed the marked change in the vegetation.' And yet even at this elevation we meet with forms of tropical plants, pothos, bananas, palms, figs, pepper, numbers of epiphytal orchids, and similar genuine tropical genera.'

The hill-station of Darjiling, the well-known sanitarium, where the health of Europeans is recruited by a temperate climate, is about 370 miles to the north of Calcutta. The ridge • varies in height from 6500 to 7500 feet above the level of the sea, 8000 feet being the elevation at which the mean temperature most nearly coincides with that of London, viz. 50°.? The forests around Darjiling are composed principally of magnolias, oaks, laurels, with birch, alder, maple, holly. Dr. Hooker draws especial attention to the absence of Leguminosa,

the most prominent botanical feature in the vegetation of the region,' which, he says, is too high for the tropical tribes of the warmer elevation, too low for the Alpines, and probably too moist for those of temperate regions; cool, equable, humid climates being generally unfavourable to the abovenamed order. • The supremacy of this temperate region consists in the infinite number of forest trees, in the absence in the usual proportion at any rate) of such common orders as Compositæ, Leguminosa, Crucifere, and Ranumculacea, and of grasses amongst Monocotyledons, and in the predominance of the rarer and more local families, as those of Rhododendron, Camellia, Magnolia, Ivy, Cornel, Honeysuckle, Hydrangea, Begonia, and epiphytic orchids.'

We regret that want of space prevents us dwelling longer on the scenes of tropical Himalaya so graphically described by Dr. Hooker. We will conclude this imperfect sketch with our traveller's description of the scenery along the banks of the great Rungeet, 6000 feet below Darjiling.

Leaving the forest, the path led along the river bank, and over the great masses of rock which strewed its course. The beautiful Indiarubber fig was

On the forest-skirts, Hoya,

parasitical

common.

parasitical Orchidice, and Ferns abounded; the Chaulmoogra, whose fruit is used to intoxicate fish, was very common; as was an immense mulberry-tree, that yields a milky juice and produces a long green sweet fruit. Large fish, chiefly cyprinoid, were abundant in the beautifully clear water of the river. But by far the most striking feature consisted in the amazing quantity of superb butterflies, large tropical swallow-tails, black, with scarlet or yellow eyes on their wings. They were seen everywhere, sailing majestically through the still hot air, or fluttering from one scorching rock to another, and especially loving to settle on the damp sand of the river; where they sat by thousands, with erect wings, balancing themselves with a rocking motion, as their heavy sails inclined them to one side or the other resembling a crowded fleet of yachts on a calm day. Such an entomological display cannot be surpassed. Cicindelæ and the great Cicadeæ were everywhere lighting on the ground, when they uttered a short sharp creaking sound and anon disappeared as if by magic. Beautiful whip snakes were gleaming in the sun: they hold on by a few coils of the tail round a twig, the greater part of their body stretched out horizontally, occasionally retracting and darting an unerring aim at some insect. The narrowness of the gorge, and the excessive steepness of the bounding hills, prevented any view excopt of the opposite mountain-face which was one dense forest, in which the wild Banana was conspicuous.'

One of the most remarkable botanical discoveries of modern days, is that of a very curious and anomalous genus of plants, named by Dr. Hooker, Welwitschia, in honour of its discoverer, Dr. Frederic Welwitsch, who first noticed this singular plant in a letter to Sir William Hooker, dated August, 1860.

I have been assured,' says Dr. Hooker, in his valuable memoir of this plant, by those who remember it, that since the discovery of the Rafflesia Arnoldii, no vegetable production has excited so great an interest as the subject of the present Memoir.' We well remember this singular plant, having seen a specimen in the Kew Herbarium soon after its arrival in this country. The following is Dr. Hooker's account of its appearance and prominent characters :

• The Welwitschia is a woody plant, said to attain a century in duration, with an obconic trunk about 2 feet long, of which a few inches rise above the soil, presenting the appearance of a flat, twolobed, depressed mass, sometimes (according to Dr. Welwitsch) attaining 14 feet in circumference (!) and looking like a round table. When full grown, it is dark brown, hard and cracked over the whole surface (much like the burnt crust of a loaf of bread); the lower portion forms a stout tap-root, buried in the soil and branching downwards at the end. From deep grooves in the circumference of the depressed mass two enormous leaves are given off, each 6 feet long when full grown, one corresponding to each lobe. These are quite

flat,

flat, linear, very leathery, and split to the base into innumerable thongs that lie curling upon the surface of the soil. Its discoverer describes these same two leaves as being present from the earliest condition of the plant, and assures me that they are in fact developed from the two cotyledons of the seed, and are persistent, being replaced by no others. From the circumference of the tabular mass, above but close to the insertion of the leaves, spring stout dichotomously branched cymes, nearly a foot high, bearing small erect scarlet cones, which eventually become oblong and attain the size of those of the common spruce fir. The scales of the cones are very closely imbricated, and contain when young and still very small, solitary flowers, which in some cases are hermaphrodite (structurally but not functionally), in others female.'

After describing these flowers in botanical terms, Dr. Hooker adds, the mature cone is tetragonous, and contains a broadly winged scale. Its discoverer observes that the whole plant exudes a resin, and that it is called “tumbo” by the natives. It inhabits the elevated sandy plateau near Cape Negro (lat. 14° 40' S. to 23° S.), on the south-west coast of Africa.' Dr. Hooker regards the Welwitschia as 'the only perennial floweringplant which at no period has other vegetative organs than those proper to the embryo itself. The main axis being represented by the radicle, which becomes a gigantic caulicle and developes a root from its base, and inflorescences from its plumulary end, and the leaves being the two cotyledons in a very highly developed and specialised condition.' *

Few countries present more objects of interest to the naturalist than the island of Madagascar, amongst the botanical treasures of which island the water yam or lace-leaf (Ouvirandra fenestralis) claims especial notice. This beautiful and singular plant, which belongs to the natural order Naiadacea, was first made known to the scientific world by Du Petit Thouars in 1822. Horticulturists are indebted to Mr. Ellis, the well-known author of Polynesian Researches, for the introduction of this singular plant into England, specimens of which may be seen in the Royal Gardens at Kew and elsewhere :

" This plant,' says Mr. Ellis, 'is not only extremely curious, but also very

valuable to the natives, who, at certain seasons of the year, gather it as an article of food--the fleshy root when cooked, yielding a farinaceous substance resembling the yam. Hence its native name ouvirandrano, literally, yam of the water ;-ouvi in the Malagasy and Polynesian languages signifying yam, and rano in the former and some of the latter signifying water. The ouvirandra is not only a rare and curious, but a singularly beautiful plant, both in structure and colour.

• Transactions of the Linnean Society,' vol. xxiv. Part I.

From

From the several crowns of the branching root growing often a foot or more deep in the water, a number of graceful leaves, nine or ten inches long, and two or three inches wide, spread out horizontally just beneath the surface of the water. The flower-stalks rise from the centre of the leaves, and the branching or forked flower is curious ; but the structure of the leaf is peculiarly so, and seems like a living fibrous skeleton rather than an entire leaf. The longitudinal fibres extend in curved lines along its entire length and are united by threadlike fibres or veins, crossing them at right angles from side to side, at a short distance from each other. The whole leaf looks as if composed of fine tendrils, wrought after a most regular pattern so as to resemble a piece of bright-green lace or open needlework. Each leaf rises from the crown on the root like a short delicate-looking pale green or yellow fibre, gradually unfolding its feathery-looking sides and increasing its size as it spreads beneath the water. The leaves in their several stages of growth pass through almost every gradation of colour, from a pale yellow to a dark olive-green, becoming brown or even black before they finally decay; air-bubbles of considerable size frequently appearing under the full-formed and healthy leaves. It is scarcely possible to imagine any object of the kind more attractive and beautiful than a full-grown specimen of this plant, with its dark green leaves forming the limit of a circle two or three feet in diameter, and in the transparent water within that circle presenting leaves in every stage of development, both as to colour and size. Nor is it the least curious to notice that these slender and fragile structures, apparently not more substantial than the gossamer and flexible as a feather, still possess a tenacity and wiriness which allow the delicate leaf to be raised by the hand to the surface of the water without injury.'

No natural order of plants has created or continues to create a greater degree of interest amongst travellers and botanists than the Orchidacee, of which more than three thousand species have been described; the anomalous structure of their reproductory parts, the singularity in form of the floral envelopes, the grotesque resemblance which many kinds bear to some object or other of the animal world, the rarity, beauty, and delicious fragrance of some forms all combine to render these plants of great

value and interest. As inhabitants of hot and damp localities, orchids are in general epiphytes, as in the Brazilian forests, in the lower portions of the Himalayan Mountains, and in the islands of the Indian Archipelago; when they occur in temperate regions, they are terrestrial in their mode of growth; in extremely dry or cold climates, orchidaceous plants are unknown. Two rare and beautiful epiphytal orchids, the Angræcum sesquipedale and A. superbum were obtained by Mr. Ellis in Madagascar and Mauritius, and introduced into this country. Of the former, the

largest

largest flowered of all the orchids, Dr. Lindley has given the following description :

• The plant forms a stem about eighteen inches high, covered with long leathery leaves in two ranks like Vanda tricolor and its allies ; but they have a much more beautiful appearance, owing to a drooping habit, and a delicate bloom which clothes their surface. From the axils of the uppermost of these leaves appear short stiff flower-stalks, each bearing three, and sometimes five flowers extending seven inches in breadth, and the same in height. They are furnished with a firm, curved, tapering, tail-like spur, about fourteen inches long. When first open the flower is slightly tinged with green except the tip, which is almost pure white; after a short time the green disappears, and the whole surface acquires the softest waxy texture and perfect whiteness. In this condition they remain, preserving all their delicate beauty for more than five weeks. Even before they expand, the greenish buds, which are three inches long, have a very noble appearance.'

To the scientific naturalist few subjects are more full of deep interest than the question of the geographical distribution of animals. Dr. Sclater, the active Secretary of the Zoological Society of London, has contributed an instructive paper, ‘On the Mammals of Madagascar,' to the second number of the Quarterly Journal of Science, from which we gather the following facts. As a general rule it is found that the faunæ and flora of such countries as are most nearly contiguous, do most nearly resemble one another, while on the other hand those tracts of land which are farthest asunder are inhabited by most different forms of animal and vegetable life. Now Madagascar, with the Mascarene Islands, is a strange exception to the rule; for the forms of Mammalia which are found in these islands are very different from the forms which occur in the contiguous coast of Africa, although the channel between Madagascar and the Continent is in one place not more than 200 miles; •The numerous mammals of the orders Ruminantia, Pachydermata, and Proboscidea, so characteristic of the Æthiopian fauna, are entirely absent from Madagascar. The same is the case with the larger species of carnivora which are found throughout the African continent, but do not extend into Madagascar. Again the highly organised types of Quadrumana, which prevail in the forests of the mainland, are utterly wanting in the neighbouring island; their place being there occupied by several genera of the inferior family of Lemurs.' Dr. Sclater shows that this anomaly is not confined to the orders already enumerated, but that similar irregularities prevail to a greater or lesser extent in every part of the mammalian series, and that in short the anomalies presented to us of

the

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