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fibres. As the parasite increases in size, and an additional supply of nutriment is required, lateral shoots are sent out from the surface, which also penetrate the bark, and are precisely similar in mode of attachment to the original seedling shoot. It is a curious fact that the fibres of the later shoots never penetrate further than those of their primitive attachment. In the adult plants the sucker-bearing shoots frequently run to a considerable distance; many of the stocks being literally covered with parasites, all of which have sprung from one seed. Mr. Griffiths says :
I have seen such shoots, which had taken their course along a decayed branch, become reflexed and return in quest, as I may express it, of a part capable of affording nourishment.
The remarkable exception which the viscum presents to the general law—that the radicle or root of the embryo shoots downwards and the plumule upwards, under all circumstances, has been confirmed by curious experiments. So certain is it that the radicle of the mistletoe will turn itself towards the body to which it is attached, whatever may be the position of that body with respect to the earth, that a cannon-ball, to which mistletoe seeds were glued on all sides, and suspended in the air, became the point of attraction for all the little radicles to direct themselves towards from all sides of the ball. · This property insures their growing upon the branches of trees to whatever side they may happen to adhere. It is asserted that a branch of mistletoe, if placed in water, has no power of absorbing this fluid itself; but that when the branch to which it is attached is immersed, then the water is readily absorbed and penetrates into the mistletoe. The following experiment was performed by De Candolle. He immersed the branch of an apple-tree, bearing mistletoe, in water previously coloured red with cochineal, which, penetrating the wood and inner bark of the apple-tree, entered into the mistletoe, when its colour was even more intense that in the former. It would appear as if these parasitic plants had an eliminating power, for it is certain that they do not attach themselves to all trees or shrubs indiscriminately. Mr. Griffiths thinks, however, that they would grow on almost any plant whose duration is sufficiently long to allow them to establish themselves. Plants with milky juice seem to be an exception. The seeds of Loranthus have been seen to germinate on a frond of Polypodium. The influence these parasites have on the stock is according to their respective proportions. If they attack a small or weakly tree, they injure it, and perhaps kill it; but when they attack large vigorous trees, no ill results seem to follow.
The mistletoe is the only green parasite in this country; and often forms a conspicuous feature in the physiognomy of vegetation on the leafless trees of winter. It chiefly abounds on the apple, the pear, and plum tree; and I have also seen it on the poplar. Some authors say it grows on the silver-fir tree; but instances of its attacking the Coniferæ are very rare. Occasionally it may be met with on the oak, but its very unusual presence on this tree has probably much to do with the peculiar reverence with which plants found in this situation were regarded by our early ancestors, and their priestly advisers the Druids. In warmer countries, where the Loranthus grows, its scarlet flowers form a most brilliant contrast to the dark green leaves of the plant by which it is supported. In Chili a leafless Loranthus covers with a scarlet carpet a large candelabra-like cactus, whose snow-white flowers, eight or nine inches long, project from it, and present a beautiful object to the eye.
Parasitical plants, properly so called, are very numerous in the vegetable kingdom, although the species of Loranthus and l'iscum alone have green leaves. There are parasites which live externally on their victims; others which are insidiously introduced into the interior, where they flourish until they pierce through the skin, come in contact with the air, and disseminate themselves. These are known by the various names of mildew, rust, smut, brand, &c. Those which attack externally assume different forms, and have either ordinary green leaves, as in the mistletoe, or brown scales and colourless stems. The brown scaly parasites attack the roots of plants, and their underground habits have caused them to be little examined. The most common species in Europe are the various kinds of Orobanche, broom rape, which attack hemp, clover, lucerne, and many other plants; and the species of Monotropa, birdsnest orchis, and Lathroa, tooth-wort, which infest the roots of the beech, the fir, and the ash. The best account of the manner of growth in brown parasites is given by Mr. Bowman, who studied with care the habits of the Lathraa squamaria. One of the most remarkable peculiarities of such plants is the constant absence of all green colour, though exposed to the strongest light. Connected with this is another curious property, that of resisting the attraction of light, towards which all the green parts of a plant irresistibly turn.
The Dodders also are true parasites, although they do not, like the mistletoe, plunge their roots into the wood and incorporate themselves with the tissue of another plant. Yet they twine themselves around the branches of trees, and send out suckers, which, becoming firmly attached to the bark, attract a sufficient amount of nutriment to support their tissue.
The dodders belong to the natural order Cuscutacer, and there are five species of dodder in Great Britain. The common English dodder is a white or reddish-looking annual, which spreads itself like a mass of living threads around branches of heath and furze, on dry wastes and commons. Unlike the mistletoe, the dodder springs originally from the ground, and when its little plumule first emerges, if it find no living plant near on which to graft itself, it withers and dies; but if there be one within reach, it surrounds the stem in a very little time, and henceforth lives by its suckers only on the fostering plant-the original root in the ground becoming obliterated and dried up. One species of dodder especially attacks the flax-plant; another the clover; and but lately in a meadow in Sussex, I saw most curious-looking masses of this clover dodder. It had attacked the growing clover in patches, which assumed the form of large rings or circles, and at a little distance it looked like carefully-arranged heaps of burned leaves or sea-weed; it was not until after close inspection that I discovered what this strange appearance was, and how terribly this intrusive plant had injured and despoiled the clover on which it throve. These parasites are very injurious to the plants they attack, depriving them of their nourishment and strangling them in their folds. Mr. Griffiths speaks of a gigantic species in Affghanistan, which even preys upon itself, and which half-covered a willow tree twenty or thirty feet high.
Of False Parasites or Epiphytes, as they are called, we have numbers of familiar instances in Great Britain. They generally fasten themselves in the crevices and hollows of the back of trees, and afterwards affix themselves so firmly, that they can only be torn away with considerable force. Lichens and mosses are of this kind. In humid atmospheres and in damp districts they are abundant, but in the warm moist woods of tropical regions they form a most striking feature in the landscape. On a single tree may be found such a number of different parasitic plants, as would cover a large space if planted in the ground. The Pothos plants then become parasitic and grow on the boughs of the loftiest trees, through whose foliage the large white flower rises. Strange Orchidaceæ and Bromeliæ, imbibing nourishment from the atmosphere, grow in the angles of the branches and fill up every crevice in the bark of the tree. The prettiest ferns, like our Lycopodium and Ivy, twine up on the surface of the trunk, while silvergrey Tillandsiæ hang from the branches; not to mention the multitude of climbers, which, once rooted in the earth, have ascended the trees and continue to flourish there when not a trace of their root remains. The long shoots of these plants
VOL. II.-NO. VI,
often stretch from one tree to another, sometimes hanging like cords, more or less obliquely down to the ground, with not a single leaf for a distance of twenty or thirty feet—these serve for the monkeys and wild cats to clamber on. The parasitical vegetation of the tropics is wonderful in beauty and extent. The Orchidaceæ and Aroideæ are the most common on the barks of trees, and these in their turn are covered with parasites. As in the animal world so it is in the vegetable, every creature has its dependent parasite. We may be excused for quoting a not very elegant, but an expressive couplet :
Large fleas have little fleas upon their backs to bite 'em,
And little fleas have lesser fleas, and so ad infinitum. Microscopic examination alone can reveal to what extent this law of mutual dependence is carried out in every living form. It is not only, however, in living vegetation or animals that we discover parasites. Several kinds are known to exist alone on dead organic bodies. The decaying trunk of a tree affords numerous examples of this sort of parasite, and the German botanist Schmid distinguishes wall, ruin, roof, plank, and rubbish plants. Others of the fungus kind grow only in the strangest situations : such as on wine-casks, in window panes, and on paper. But it is impossible to enlarge on this attractive subject, which would form a paper of itself, whilst we have our branch of Mistletoe for a text waiting for further notice.
The fact that this curious plant is bright and green when all Nature is wrapped in her winter mantle may account for its constant association with Christmas festivities and decorations. Then it has the attraction of association with bygone times and ages. Christmas itself is not now what it used to be in the days of the old Tudors, who, with their maskings and revellings, seem to us somewhat coarse in their boisterous merriment. With our increasing refinement we have lost perhaps some of the spirit of the season, and we believe almost the only relic of the ancient license of the occasion lingers still in some remote country-houses, and in the servants' halls of the present time. John still thinks himself at liberty to kiss Mary under the mistletoe, and the overhanging shadow of the mysterious plant saves Mary's blushes. The superstition connected with the mistletoe is in its character something like that which surrounds the four-leaved shamrock. St. Patrick's touch sanctified the one, and the association of the other with our country's carliest priests—the Druids—has hallowed its history. The doctrines inculcated by the Druids were, in many respects, far in advance of the people by whom they were surrounded. They regulated all religious services and
were the ministers of many things, both secular and sacred. They worshipped many of the Roman deities, and regarded the oak as a sacred tree. Under its shadow they performed most of their sacrifices, and no religious ceremony was entered upon by them without wearing a garland of its leaves. The mistletoe growing on the oak received from them the same homage as the tree itself. The ceremony of cutting the mistletoe from the oak is described by Pliny, and seems to have been the occasion for a great religious festival. It took place as near the 10th of March in each year as possible, and was performed by the Arch Druid himself, who, having tied two white bulls to the tree by their horns, then mounted the tree, clothed in white, and with a knife of pure gold separated the mistletoe from its parent tree, which was received in a “white sagum,” or cloth made of wool; this done, the bulls were sacrificed, and they proceeded to the further observances and feastings. Our own national custom of decorating our churches and homes with mistletoe at Christmas time may be a remnant of this old superstition. Moreover, it would appear that the Druids were the medicine-men of the time, and in their prescriptions the mistletoe was a frequent ingredient to be taken with incantations. Pliny tells us they had a name for it equivalent to All-heal, and it was esteemed peculiarly good in epilepsy or falling sickness. This reputation does not seem to have disappeared with the Druids; for, although some of the ancients looked upon the mistletoe as poisonous, the old herbalist Gerarde, in 1636,
. A few berries of the mistletoe, bruised and strained into oile and drunken, hath presently and forthwith rid a grievous and sore stitch.
He also quotes Galen, who says--
His acrimony overcometh his bitterness, for if it be used in outward applications, it draweth humours from the deepest and most secret parts of the body, spreading and dispersing them abroad and digesting them.
We are inclined to think that the imagination of the patient had more to do with the efficacy of the mistletoe plasters, as it has with many modern and still favourite remedies, than any virtue in itself. The only practical use to which we now apply the berries of the mistletoe is in the manufacture of birdlime.
Much discussion has taken place as to whether the Loranthus or Viscum album was the true mistletoe of the Druids. To my mind there can be but one conclusion in favour of the latter. Loranthus does not naturally grow in Great Britain, and the true mistletoe, l'iscum album, as also