SYMPATHIES AND ANTIPATHIES. 209 all around it. The effect of the darnel in a field of corn is equally malignant; and that of the crisium among If, however, certain plants seem to entertain a mutual hatred, there are many which apparently nourish a very genuine and earnest sympathy. Certain kinds of mushroom, as the morell, are always found at the feet of the elm and the ash; the salicaria, or smoked willow-herb, as its name implies, in the neighbourhood of willows. Others, too weak to rise in the world without the assistance of the strong, support themselves upon their trunks and branches, and by this means succeed in gaining the highest points. In Italy the vine enfolds itself around the elm, now coyly shrinking from it, now clinging closer and yet closer, and describing, in its capricious movements, the most graceful but fantastic undulations. Hence the allusion of Shakspeare: "The female ivy so Enrings the barky fingers of the elm;" while Milton describes how the first gardener "Led the vine To wed her elm; she spoused, about him twines Everybody knows how the "lush woodbine" and the fragrant honeysuckle smiling spread themselves about the green hedgerows, or creep up the cottage wall and the old manorial gable, glorifying them with the bloom of beauty, and filling the air with honied sweetness. The nasturtium and the canariensis, with their bright gay flowers, likewise show themselves to be in need of a "helping hand." So, too, the convolvulus, with its delicate pink and trumpet-shaped blossoms, winds among the tenacious stems of the privet hedge, or with slender tendrils clasps the bole of the rugged oak. But there is almost a world of creeping and climbing plants which are unable to flourish without prop or stay, and some of which are invariably found in connection with a particular tree, or affecting a special situation. Frequently this sympathizing disposition tends to the irretrievable injury of the plant which calls it forth. The 212 THE TROPICAL LIANAS. elm is often choked by the close embraces of the ivy. The tropical lianas, or creepers, almost invariably kill the trees around whose once sturdy trunks they have entwisted their own vigorous and aggressive life, and develop in such luxuriance as to render the forest actually impassable. Here is a traveller's picture :-" The leafy crowns of the trees, scarcely two of which could be seen together of the same kind, were far away above us, in another world as it were. We could only see at times, where there was a break above, the tracery of the foliage against the clear blue sky. Below, the tree trunks were everywhere linked together by sipós; the woody, flexible stems of climbing and creeping trees, whose foliage soared far away above, mingled with that of the taller independent trees. Some were twisted in strands like cables, others had thick stems contorted in every variety of shape, entwining, snake-like, round the tree-trunks, or forming gigantic loops and coils among the larger branches; others, again, were of zigzag shape, or indented like the steps of a staircase, sweeping from the ground to a giddy height." The deadly influence exercised by these parasites of the American forest finds a vivid illustration in the pages of Burmeister. In the Brazilian wilderness, he tells us, is often to be seen a singularly impressive phenomenon-a couple of trees, equally strong and robust, and several feet in girth; the one, majestic in aspect and of an uniform rotundity, resting upon a foundation of solid roots extended over a considerable area and shooting perpendicularly upwards to an elevation of 80 or 100 feet; the other, with swelling sides, and hollow for half its stature, leaning against the |