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for though by far the greater proportion of many species of insects perish at the close of autumn, yet several individuals, probably those that emerge the latest from the chrysalis state, are only rendered torpid by the cold; and the moderate warmth of a bright winter's day, is sufficient to rouse them into activity.

As soon as the earth is softened, moles go to work in throwing up their hillocks. Under some of the largest, a little below the surface of the ground, they make their nests of moss, in which four or five young are found at a time. These animals feed on worms, beetles, and the roots of plants.

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They do much mischief in gardens, by loosening and devouring flower roots, and in the fields by rendering the surface of the soil uneqnal by their hillocks, which obstruct the scythe in mowing. They are also accused of piercing the sides of dams and canals, and letting out the water; the strong muscles of their fore-feet, together with their hand-like form, admirably fit this animal for swimming; and it has lately been observed, that in this

way moles

pass from the shore to the little islands in some of the Scotch lakes.

Many plants emerge from under-ground in February, but few flowers as yet adorn the fields and pastures. Snow-drops are sometimes fully opened from the beginning of the month, often peeping out amidst the snow.

Already now the snow-drop dares appear,
The first pale blossom of the unripened year ;
As Flora's breath by some transforming power,
Had changed an icicle into a flower.
Its name and hue the scentless plant retains,
And winter lingers in its icy veins.

MRS. BARBAULD.

The elder-tree discloses its flower-buds; the catkins of the hazel become very conspicuous in the hedges; young leaves are budding on the gooseberry and currant-trees about the end of the month; and those causes are now in full activity which produce the springing of plants and the renovation of vegetable life.

The first vital function in trees, after the frost is moderated, and the earth sufficiently thawed, is the ascent of the sap, which is taken up by the absorbent vessels composing the inner bark of the tree, and reaching to the extremity of the fibres of the roots; the water thus imbibed by the roots is there mixed with a quantity of saccharine matter, and formed into sap, whence it is distributed in great abundance to every individual bud. The amazing quantity of sweet liquid sap provided for the nourishment of some trees, is evident from a prevalent custom in this country, of tapping the birch in the early part of spring; thus obtaining from each tree a quart or more of liquor, according to its size, which is fermented into a species of wine : the same method is also practised in the tropical regions to procure the favourite liquor of the inhabitants, palm wine ; and a similar custom is observed in the northern parts of America with regard to the sugar. maple, the juice of which boiled down yields a rich sugar, each tree affording about three pounds. This great accession of nourishment causes the bud to swell, to break through its covering, and to spread into blossoms, or lengthen into a shoot bearing leaves. This is the first process, and, properly speaking, is all that belongs to the springing or elongation of trees; and in many plants, that is, all those which are annual or deciduous, there is no other process; the plant absorbs juices from the earth, and in proportion to the quantity of these juices increases in size : it expands its blossoms, perfects its fruit, and when the ground is incapable by drought or frost of yielding any more moisture, or when the

ASCENT OF THE SAP IN TREES.

55

vessels of the plant are not able to draw it up, the plant perishes. But in trees, though the beginning and end of the first process is exactly similar to what takes place in vegetables, yet there is a second process, which at the same time that it adds to their bulk, enables them to endure and go on increasing through a long series of years.

The second process begins soon after the first, in this way: -At the base of the foot-stalk of each leaf a small bud is gradually formed; but the absorbent vessels of the leaf having exhausted themselves in the formation of the bud, are unable to bring it nearer to maturity: in this state it exactly resembles a seed, containing within it the rudiments of vegetation, but destitute of absorbent vessels to nourish and evolve thé embryo. Being surrounded, however, by sap, like a seed in moist earth, it is in a proper situation for growing; the influence of the sun sets in motion the juices of the bud and of the seed, and the first operation in both of them is to send down roots a certain depth into the ground for the purpose of obtaining the necessary moisture. The bud accordingly shoots down its roots upon the inner bark of the tree, till they reach the part covered by the earth. Winter now arriving, the cold and defect of moisture owing to the clogged condition of the absorbent vessels, cause the fruit and leaves to fall, so that except the provision of buds with roots, the remainder of the tree, like an annual plant, is entirely dead: the leaves, the flowers and fruit are gone, and what was the inner bark, is no longer organised, while the roots of the buds form a new inner bark; and thus the buds with their roots contain all that remains alive of the whole tree. It is owing to this annual renovation of the inner bark, that the tree increases in bulk; and a new coating being added every year, we are hence furnished with an easy and exact method of ascertaining the age of a tree by counting the number of concentric circles of which the trunk is composed. A tree, therefore, properly speaking, is rather a congeries of a multitude of annual plants, than a perennial individual. The sap in trees always rises as soon as the frost is abated, that when the stimulus of the warm weather in the early spring acts upon the bud, there should be at hand a supply of food for its nourishment; and if by any means the sap is prevented from ascending at the proper time, the tree

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infallibly perishes. Of this a remarkable instance occurred in London, during the spring succeeding the hard winter of the year 1794. The snow and ice collecting in the streets so as to become very inconvenient, they were cleared, and many cartloads were placed in the vacant quarters of Moor. fields : several of these heaps of snow and frozen rubbish were piled round some of the elm-trees that grew there. At the return of spring, those of the trees that were not surrounded with the snow expanded their leaves as usual, while the others, being still girt with a large frozen mass, continued quite bare; for the fact was, the absorbents in the lower part of the stem, and the earth in which the trees stood, were still exposed to a freezing cold. In some weeks, however, the snow was thawed, but the greater number of the trees were dead, and those few that did produce any leaves were sickly, and continued in a languishing state all summer, and then died.

The farmer is now impatient to begin his work in the fields, as soon as the ground is sufficiently thawed. He ploughs

his fallows, sows beans and peas, rye and spring wheat; sets early potatoes; drains wet lands; dresses and repairs hedges; lops trees, and plants those kinds that love a wet soil, such as poplars, alders, and willows.

Of all our native birds, none begins to build so soon as the raven : by the latter end of this month it has generally laid its eggs and begun to sit. The following anecdote, illustrative of its attachment to its nest, is related by Mr. White in his “Natural History of Selbourne :”—“In the centre of this grove there stood an oak, which, though shapely and tall on the whole, bulged out into a large excrescence about the middle of the stem. On this a pair of ravens had fixed their residence for such a series of years, that the oak was distinguished by the name of the raventree. Many were the attempts of the neighbouring youths to get at this eyry ; the difficulty whetted their inclinations, and each was ambitious of surmounting the arduous task. But when they arrived at the swelling, it jutted out so much in their way, and was so far beyond their grasp, that the most daring lads were awed, and acknowledged the undertaking to be too hazardous. So the ravens built on, nest upon nest, in perfect security, till the fatal day arrived in

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which the wood was to be levelled. It was in the month of February, when those birds usually sit. The saw was applied to the butt, the wedges were inserted into the opening, the woods echoed to the heavy blows of the beetle and mallet, the tree nodded to its fall, but still the dam sat

At last, when it gave way, the bird was flung from her nest; and though her parental affection deserved a better fate, was whipped down by the twigs, which brought her dead to the ground.”

Of the raven, Stanley says, in his interesting work on birds—“ With us the raven may be called the herald of the year; for as early as the latter part of January, if the weather be mild, or, at all events, in the beginning of February, some faithful pair (for the union of male and female is for life) may be seen looking into the state of their nursery tenement, usually constructed on the upper and most inaccessible branching forth of some high tree, where they have been known to build beyond the memory of the most ancient chronicler of the parish.'

Mr. Knox, in his “Ornithological Rambles in Sussex," gives a long and most interesting account of a pair of ravens, whose motions and operations he seems to have watched very narrowly. He says, speaking of Petworth Park, after describing the untimely fate of one pair of birds which had built in that locality, and which were destroyed by an ignorant keeper—" Years passed away, and the raven continued unknown in this part of West Sussex, until one day in March, 1843, when, riding in the park near a clump of tall old beech trees, whose trunks had been denuded by time of all their lower branches, my attention was suddenly arrested by the never-to-be-mistaken croak of a raven, and the loud chattering of a flock of jackdaws.

“I soon perceived that these were the especial objects of his hatred and hostility; for after dashing into the midst of them, and executing several rapid movements in the air, he succeeded in effectually driving them to a considerable distance from his nest. During this manæuvre, the superior size of the raven became more apparent than when viewed alone, and his power of flight was advantageously exhibited by comparison with that of his smaller congeners. The latter, indeed, seemed to bear about the same relation to

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