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right to left, up other plants, from which, by means of vessels, it draws its nourishment." The "little spiral body" proceeding from the seed, is to be compared with the fibres which seeds send out in ordinary cases: and the comparison ought to regard both the form of the threads and the direction. They are straight; this is spiral. They shoot downwards; this points upwards. In the rule, and in the exception, we equally perceive design.

III. A better known parasitical plant is the ever-green shrub, called the misseltoe. What we have to remark in it, is a singular instance of compensation. No art hath yet made these plants take root in the earth. Here therefore might seem to be a mortal defect in their constitution. Let us examine how this defect is made up to them. The ́seeds are endued with an adhesive quality so tenacious, that, if they be rubbed upon the smooth bark of almost any tree, they will stick to it. And then what follows? Roots springing from these seeds, insinuate their fibres into the woody substance of the tree; and the event is, that a misseltoe plant is produced next winter*. Of no other plant do the roots refuse to shoot in the ground;

* Withering, Bot. Arr, vol. i. p. 203, ed. 2d,

of no other plant do the seeds possess this adhesive, generative quality, when applied to the bark of trees.

IV. Another instance of the compensatory system is in the autumnal crocus, or meadow saffron (cholcicum autumnale). I have pitied this poor plant a thousand times. Its blossom rises out of the ground in the most forlorn condition possible; without a sheath, a fence, a calyx, or even a leaf to protect it: and that, not in the spring, not to be visited by summer suns, but under all the disadvantages of the declining year. When we come, however, to look more closely into the structure of this plant, we find that, instead of its being neglected, Nature has gone out of her course to provide for its security, and to make up to it for all its defects. The seed-vessels, which in other plants is situated within the cup of the flower, or just beneath it, in this plant lies buried ten or twelve inches under ground within the bulbous root. The tube of the flower, which is seldom more than a few tenths of an inch long, in this plant extends down to the root. The stiles in all cases reach the seed-vessel; but it is in this, by an elongation unknown to any other plant. All these singularities contribute to one end.

"As this plant blossoms late in

the year, and, probably, would not have time to ripen its seeds before the access of winter, which would destroy them; Providence has contrived its structure such, that this important office may be performed at a depth in the earth out of reach of the usual effects of frost*." That is to say, in the autumn nothing is done above ground but the business of impregnation; which is an affair between the antheræ and the stigmata, and is probably soon over. The maturation of the impregnated seed, which in other plants proceeds within a capsule, exposed together with the rest of the flower to the open air, is here carried on, and during the whole winter, within the heart, as we may say, of the earth, that is, "out of the reach of the usual effects of frost." But then a new difficulty presents itself. Seeds, though perfected, are known not to vegetate at this depth in the earth. Our seeds, therefore, though so safely lodged, would, after all, be lost to the purpose for which all seeds are intended. Lest this should be the case, 66 a second admirable provision is made to raise them above the surface when they are perfected, and to sow them at a proper distance:" viz. the germ grows up in the spring, upon a fruit-stalk, * Withering, ubi supra, p. 360.

accompanied with leaves. The seeds now, in common with those of other plants, have the benefit of the summer, and are sown upon the surface. The order of vegetation externally is this:-The plant produces its flowers in September; its leaves and fruits in the spring following.

V. I give the account of the dionæ muscipula, an extraordinary American plant, as some late authors have related it: but whether we be yet enough acquainted with the plant, to bring every part of this account to the test of repeated and familiar observation, I am unable to say. "Its leaves are jointed and furnished with two rows of strong prickles; their surfaces covered with a number of minute glands, which secrete a sweet liquor that allures the approach of flies. When these parts are touched by the legs of flies, the two lobes of the leaf instantly spring up, the rows of prickles lock themselves fast together, and squeeze the unwary animal to death*." Here, under a new model, we recognize the ancient plan of nature, viz. the relation of parts and provisions to one another, to a common office, and to the utility of the organized body to which they belong. The attracting syrup, the rows of

* Smellie's Phil, of Nat. Hist. vol. i. p. 5.

strong prickles, their position so as to interlock, the joints of the leaves; and, what is more than the rest, that singular irritability of their surfaces, by which they close at a touch; all bear a contributory part in producing an effect, connected either with the defence or with the nutrition of the plant.

CHAPTER XXI.

THE ELEMENTS.

WHEN we come to the elements, we take leave of our mechanics; because we come to those things, of the organization of which, if they be organized, we are confessedly igno

rant.

This ignorance is implied by their name. Το say the truth, our investigations are stopped long before we arrive at this point. But then it is for our comfort to find, that a knowledge of the constitution of the elements is not necessary for us. For instance, as Addison has well observed, we know water sufficiently, when we know how to boil, how to freeze, how to evaporate, how to make it fresh, how to make it run or spout out, in what quantity and direction we please,

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