ns, where wanted, for the further nourishment wth of the plant?* How nicely are the leaves by the wide and extended surfaces they are present, the delicate construction of their tubes s, and their porous and transparent texture, for portant services they are made to yield in the y of vegetation!-See, how they serve to conprepare the sapt-how they prevent by their The moisture at the root from being too speedily ted-how they embrace and defend the flower ud, and carefully conceal the fruit before it armaturity; and by catching the undulations of le breeze, how they convey that motion to the

e result of all Mr Knight's experiments and remarks," Sir th observes, “seems to be, that the fluids destined to nourish. being absorbed by the root, and become sap, are carried up leaves by these vessels, called by him central vessels, from tion near the pith. A particular set of them appropriated af, branches off, a few inches below the leaf to which they om the main channels that pass along the alburnum, and m the fibres of the root to the extremity of each annual shoot it."

far the greater portion of the sap is carried into the leaves; at importance and utility of which, to the plant itself, Mr theory,” it has been observed, “ is the only one that gives us ate or satisfactory notion. In those organs the sap is exhe action of light, air, and moisture, three powerful agents, it is enabled to form various secretions, at the same time a superfluous matter passes off by perspiration. These seot only give peculiar flavours and qualities to the leaf itare returned by another set of vessels," as Mr Knight bas ted, "into the new layer of bark, which they nourish and erfection, and which they enable, in its turn, to secrete matnew layer of alburnum the ensuing year."

trunk and branches, which, (for ought we know,) may be as essentially necessary to the vegetable life as exercise is to animal health. What an excellent clothing does the bark afford, not only for protecting the stem and branches from external injury, but from the hurtful extremes of heat and cold, independent of the other important end it is made to serve in the economy of vegetation ?* What evident marks of wisdom and design do the Flowers evince in their beautiful and delicate construction†-how nicely are they formed for the protection and nourishment of the first and tender rudiments of the fruit; and when it has attained more firmness and solidity, how readily do they relinquish their charge, and drop off in decay when no longer ne

t

• The functions of the parenchymatous and cortical parts of the bark, Sir H. Davy observes, are of great importance. The tubes of the fibrous parts appear to be the organs that receive the sap; the cells seem destined for the elaboration of its parts, and for the exposure of them to the action of the atmosphere, and the new matter is annually produced in the spring, immediately on the inner surface of the cortical layer of the last year," and thus it is to be accounted for, that s new layer of wood is formed every year, and the age of a sound tree is to be known, when cut down, by the number of these layers or rings it contains.

↑ The myriads of insects which are attracted by the charms of the Flowers of the plants, are well known to act a most important part in the business of impregnation. What wisdom is therefore evidenced in those brilliant colours, and delightful odours, which serve to draw so many of those busy meddlers to nestle among the nectaries, and revel amidst the pistils, and stamens, and anthers of flowers; by which means, they are made to contribute essentially towards rendering the plant fruitful, while to human appearance they seem solely occupied in robbing it of its sweets!

ssary! How wonderfully does the fruit, in some asses, envelope and protect the seed till it has arrived maturity ;and, lastly, what a passing strange piece organized mechanism is the seed itself;* and being cessary for the reproduction of its species, what a narkable provision is made for its preservation and ccession ! What, but the wisdom of a Deity, could

*It has been discovered by the microscope, that the smallest seeds itain the rudiments of the future plant in embryo; but in some, this liscoverable by the naked eye, as in the Kidney Bean, where the y ribs of the leaves of next year's plant are visible.

In this respect the seed of a plant may, indeed, be compared to the mal fœtus, as it seems only to require to be put into that proper ation, which may be denominated its native element, in order to elope itself and arrive at maturity.

The analogy between vegetable and animal life approaches much rer than is generally imagined. Recent observation has traced the gress of the sap from its first absorption by the roots, through the itral vessels of the plant, into the annual shoot, leafstafk, and leaf, ence it is returned, and, descending through the bark, contributes the process of forming the wood; thus describing a course, and filling functions, very nearly correspondent to the circulation of the ood. There is something equivalent to respiration through the whole ant, the leaves principally performing the office of the lungs ;—it has e series of vessels to receive and convey the alimental juices, anvering to the arteries, lacteals, veins, &c. of animals; and a second t of trachea wherein air is continually received and expelled. It sorbs food regularly, both from the earth and from the atmosphere, onverting the most vitiated effluvia, in the process of digestion, into ve purest air. The vegetable and animal parts of creation are thus counterbalance to each other, the noxious parts of the one proving lutary food to the other. From the animal body certain effluvia are ontinually passing off, which vitiate the air, and nothing can be more rejudicial to animal life than their accumulation; while, on the other and, nothing can be more favourable to vegetables than these very fluvia, which they accordingly absorb with great avidity, and convert nto the purest air.

have devised that those seeds which are most exposed to the ravages of the inhabitants of the forest, should not only be doubly, but some of them trebly enclosed!* -that those most in request as articles of food, should be so hardy and abundantly prolific;† and, that seeds

As in the Walnut, we have first a thick pulpy covering, then a hard shell, within which is the seed enclosed in a double membrane.

Wheat, the most nutritive of the various grains which are made use of by man for the purpose of food, is not only most widely dif fused, being to be found in Europe, in Asia, in northern Africa, north and south America, New Holland, (where it is now very extensively cultivated,) as well as in Van Dieman's Land, but, is so abusi antly prolific, that the following extraordinary fact has been quoted br Dr Rigby, in his "Holkham," from The Philosophical Transactions, vol. lviii. p. 203. Mr C. Miller, of Cambridge, sowed some wheat the 2d of June 1766, and on the 8th of August one plant was taken separated into eighteen parts, and replanted. These plants were agala taken up and divided between the middle of September and the midd of October, and again planted separately to stand the winter. T second division produced sixty-seven plants. They were again take up and divided, between the middle of March and the middle April, and produced five hundred plants. The number of ears th obtained from a single grain of wheat was 21,109; which measu three pecks and three quarters of corn, weighed forty-seven pous seven ounces, and were estimated at 576,840 grains.

But this, you will say, was not a natural, or, at least, a common EISE. and the amazing produce was the consequence of much care, more than an ordinary degree of labour. Sir Humphry Davy, he 'ever, mentions, that he had counted from 40 to 120 stalks produc from a grain of wheat, in a moderately good crop of drilled whest. and we had an instance, last year, in our own neighbourhood, whe on Mr Thomas Hume's farm at Southfield, a single pickle of c deposited accidentally by the side of a wall, produced no less tha 116 stems, yielding the almost incredible quantity of 15,000 pickis The circumference of the stalk, I have just learned, was 1 inch 7and the breadth of the leaf exactly the same.

Davy's Agricultural Chemistry, p. 215, edit. 1821.

n general, which are the sport of so many casualties, nd exposed to injury from such a variety of accidents, hould not only come forth in such prodigious numers, but be possessed of a principle of lasting vitality, hich makes it indeed no easy matter to deprive them their fructifying power. Plants are also mulplied and propagated by a variety of ways, which rengthen the provision made for their succession.

Nor is the finger of providence less visible in the eans of diffusing or spreading abroad vegetables, an in the provision made for keeping up their sucession. The earth may be said to be full of the good

The seeds of the white poppy, are said, not unfrequently to amount the almost incredible number of 32,000; those of the tobacco lant to 360,000; and the common fern, it is asserted, sometimes proaces the amazing quantity of a million of seeds on each individual af. Indeed, so great are the prolific powers of the vegetable kingom, that, it has been justly remarked, a single plant of almost any ind, if suffered to increase without interruption, would in time overun the terrestrial globe!

† It is observed, by Paley, that "a grain of mustard seed has been nown to lie in the earth for a hundred years, and, as soon as it had cquired & favourite situation, to shoot as vigorously as if just gathered rom the plant!" But we are just informed, in a respectable periolical publication, that a still more extraordinary instance of the enacity of life in the vegetable kingdom, has occurred, or rather, has come to light, "some time since, in the royal park of Bushey. Some small portion of it was broken up for the purpose of ornamental culture, when immediately several flowers sprang up, of the kinds which are ordinarily cultivated in gardens; this led to an investigation, and it was ascertained that this identical plot had been used as a garden not later than the time of Oliver Cromwell, more than 150 years before.”—August, 1826.

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