in growth until it becomes an organ concurrent with the others in the life of the plant. The bud may therefore be considered as a fundamental element in the plant, which, without it, would soon perish. It is the bud which year by year repairs the losses, supplies the flowers, the leaves, the branches which have disappeared. Through its means the plant increases in growth. Through it, its existence is prolonged. The bud is the true renovator of the vegetable world. It may be said, in fact, that a plant is all bud; there is scarcely any part that does not produce them; the roots, the leaves, the flowers even, may accidentally give birth to buds, for nature never loses sight of the phenomena essential to organic life—namely, the production of new beings. Buds are of two kinds, namely, buds which produce leaves and branches, and buds which contain at once leaves and flowers.

The leaf bud is a scaly coneform organ placed on the axis of a leaf —in fact, a rudimentary leaf or branch, so to speak, formed as the growing season is about to close: it is, therefore, rather the cradle in which the leaf is to be nursed in the coming spring, than the parts of the leaf itself in a rudimentary condition. The growing point is composed of cellular tissue possessing special powers of vitality and growth, and in direct communication with the horizontal system of the pith of the stem.

The arrangements of the scales of buds are very various: the scales being rudimentary leaves, the arrangements of scales are also the arrangements of leaves. Some of their forms are familiar to us. There are no vascular structures within the point of the bud itself, but spiral vessels and woody fibre approach near to the base of the cone. The flower-bud, on the other hand, is a stationary growing focus surrounded by rudimentary leaves, the growing point of which has become quasi-paralysed, and has no power of elongating itself; it is, in short, a stunted branch, from which the power of elongating itself by growth has been withdrawn, for it is well known that a stagnation of the juices is favourable to the production of flower-buds.

It is then necessary to avoid confounding tle leaf-bud with the flower-buds, which contain only the flower ready to burst, to E 2

astonish with its beauty and disappear. A rose or pink bud only encloses the flowering petals ready to open; while the /ea/-bud,m its serried and complex mass, includes all the elements necessary a young plant, and as we shall see, it suffices —to the production.of to produce a new individual.;

Buds are the first age and the earliest form of the vegetable axis; they occupy the summit of the axis, viz., the arm-pit or —

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Fig. 60. Bud of the Horse Fig. 59.—Bud of the Fig. 6l.--Evolving fA ie leaf-bud of Horse Chestnut. Chestnut.

axil which they are destined to prolong. In the case of herba. 4 ceous plants in general, and with a great many trees of equinoxial countries, whose vegetation, so to speak, is increasing, the buds ate Es naked, that is to say, all the young leaves resemble each other, a0 give out true leaves as they enlarge. But in countries. where the: winter, more or less vigorous, would destroy the delicate organs, the external leaves which cover the others are subjected to modifications which transform them into protecting orgaris. They ave — changed into scaly coriaceous membranes, frequently furnished 0D the interior with an abundant down of a thick hair, or with 9 coating of resinous juice, insoluble in water, and preserving COU” siderable warmth. Under this shelter the rudiments of the you" plant are so effectually swaddled up, so to speak, as to be thoroughly protected from the external air. Experiment proves that where the buds are detached from the tree, and the wound covered oV@F with a varnish, they have remained for a long time under wate? — without experiencing the least change. *

The scales are modified leaves then, but it is not always the same part of the leaf which constitutes them. Nature employs divers processes for transforming a leaf into a scale. Again, between the scales of a bud and the leaf which they enclose, we frequently find a series of intermediate forms which throw considerable light on the metamorphoses of which the leaf is the seat when it passes

4 po ¢ the Corrant (Ries) Fig. 6 dual ig. 02. into scales and leaves.

insensibly from one state to the other. Fig. 62, which represents the Currant leaf (Rides) gradually passing from the leaf to the scaly state, shows sufficiently the transition from the one organ to the. other, to render any further detail unnecessary. e leaves are not always disposed in the same © manner upon the bud, whether we consider them in their isolated state, or in the position they » occupy in reference to the others. The mode of foliation sometimes becomes a characteristic very useful to the forester when he wishes to acquaint himself with the constitution of the trees during winter. Let us consider each leaf independent of the Fig. 63.—Bud of others, and behold the different situations that the the Birch, leaf may assume towards the interior of the bud. It may be folded up transversely in such a manner that the upper part rests over the lower, as in the Tulip-tree (Lwriodendron tulipifera), Fig. 64. It may fold in its length in such a manner that one half of the leaf may lie over the other half, as in the Almond-tree (Amygdalis sinensis), Fig. 65. It may be folded several times in fan-shape, as in the graceful Birch-tree (Fig. 63); rolled round

Fig. 6 ig. 02 g. 6 dual ig. 02. po ¢ the Corrant (Ries) into scales and leaves.

Fig. 64.—Leaf-bud of the Tulip-tree. Fig. 65.—Leaf-bud of the Almond. %

Fig. 66.—Leaf-bud of the Poplar.

Fig. 67.—Leaf-bud of the Indian Shot.

Indica), Fig. 67;itself, as it were, as in the Indian Shot (Canna as in tid outwardly,rounded on both edges, which reflect each other as in the Poplar inwardly, Fig. 72, or (Rumex),Dock-weed (Populus alba), Fig. 66. We need not enter into more minute details on this subject. represent vertical sections of the SageFigs. 68, 69, and 70, which

Fig. 68.—Transverse leaf of Fig. 69.—Bud of Iris. Fig. 70.—Section of a bud of Lilac. Sage bud.

(Silvia officinalis), Lilac (Syringa vulgaris), and the well-known Iris, will suffice to prove the mutual connection of the young leaves in certain vegetables, while they are yet shut up in the bud. In most trees of temperate regions the buds make their appearance in spring, stopping at an early stage of their development, and only elongating themselves in the following spring. They ramify slowly, and it is only once a year that branches are produced. Nevertheless, in the case of the Peach-tree and the Vine, two generations of branches are produced. The cause of this is, that their scaly buds have remained stationary during the autumn and winter of the preceding year, have elongated themselves in the spring and given birth at the axils of their leaves to buds, which in place of remaining stationary, and developing themselves only at the commencement of the approaching season, grow without interruption, and produce new branches. French horticulturists have given the name of prompt-buds to these shoots. Branches which, on the other hand, only carry scale buds, and develop themselves the year after, are called dormant buds. We have spoken of normal buds, which are borne on the axils of the leaves, or which terminate the axis. There are others which present themselves without any order, and the exact spot where they present themselves cannot beforeseen. These are adventitious

Peeoe buds: they present themselves on all parts of the vegetable, now Afw upon the stem, the leaves, the flowers, and the roots. The root of the Sumac, or Stag’s-horn-tree of Virginia (Rhus Cotinus), for example; of the Dutch Poplar or Pollard Willow (Salix Alba); of the common Acacia, and many others, run horizontally in the soil very near the surface, producing adventitious buds, which root themselves rapidly, and rapidly multiply the plant, so that in a few years they become a considerable nuisance.

The formation of adventitious buds is frequently produced by accidental irritation. The wheel of a cart, for instance, grazes the ; or the root of a tree is wounded by the passing plough-share, and an adventitious bud results. If we cut down the head of a group of forest trees; the plants which, left to themselves, would have become stately trees, are transformed into stunted groups which cover themselves afterwards with branches, all of the same age and the same strength; they have been transformed from trees of stately growth to pollarded dwarfs. In the case of the Willow, this principle of adventititious budding has been largely utilised. Willows of enormous trunks, but short and deformed, surmounted by a thick tuft of branches, as in the engraving at the head of this 4 chapter, are commonly known as pollards, and owe their singular appearance to the regular and periodical cutting to which they are subjected. In consequence of this mutilation, a great number of 4 adventitious shoots are formed, which subsequently produce sO many branches of like size. These branches are cut to make — ' supports for young trees, for pea-sticks in horticultural districts, In Epping 4 countries. wine-producingandas props for the vine in Forest, in the neighbourhood of London, it has been the custom from time immemorial to have annual sales of these cuttings, at which the neighbouring inhabitants are supplied with wood both for firing and horticultural purposes.

When the Poplar-tree of Italy (Populus fastignatis) reaches twenty-five or thirty years, it is cut down, when it forms planks of some value; but it is also pruned every five years, the result of pruning being numerous adventitious buds, which produce branches much used for fences and for fire-wood,

Buds are placed upon the stem at regulated intervals, where q

they develop themselves in the form of branches, and extend the being carried through them to every leaf andtree, nourishment that, without injury to peculiaritiesfibre. It is also one of their these organs, they may be separated from the parent plant and placed upon another, which, so to speak, becomes its nurse. Horticulturists profit by this circumstance to produce some of their finest flowers and fruits. This process, known to gardeners as budding or grafting, is practised in many different ways, but in all the principle is the same; the bud without any of the wood is carefully removed from the parent tree and applied to a corresponding cut in the nursing one, covering the wound so as to keep out the air. Fig. 71 shows the manner in which the cushion graft fg is performed; B represents the bud [@ after it has been removed from the ji parent branch; a the nursing stem in which an incision in the form of a T has been made to receive it; c the graft secured in its place by means of wool or cotton thread, wound lightly, but closely round both. The bud continues to grow on its new nurse, and in course of time it forms a branch or head of a tree producing the same flowers

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