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sets, they are directed to the west. During the night, or in rainy weather, these leaves are horizontal; and their inferior surfaces are turned toward the earth. The helianthus, or sunflower, also, follows the course of the sun:

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Great Helianthus guides o'er twilight plains
In great solemnity his dervise trains;
Marshalled in fives each gaudy band proceeds,
Each gaudy band a plumed lady leads;
With zealous steps he climbs the upland lawn,
And bows in homage to the rising dawn;
Imbibes with eagle-eye the golden ray,
And watches, as it moves, the orb of day.

What has been denominated the sleep of plants, affords an instance of another species of vegetable motion. The leaves of many plants fold up during the night; but, at the approach of the sun, they expand with new vigour. The common appearances of most vegetables are so changed in the night, that it is difficult to recognise the different kinds, even by the assistance of light.

The modes of folding in the leaves, or of sleeping, are extremely various. But it is worthy of re

The numerous florets, which constitute the disk of this flower, contain in each five males surrounding one female; and the five stamens have their anthers connected at top, whence the name of the class confederate males.'

2 The seeds of many plants of this class are furnished with a plume, by which admirable mechanism they are disseminated by the winds far from their parent stem, and look like a shuttlecock, as they fly. Other seeds are disseminated by animals: of these some attach themselves to the hair or feathers by a gluten, as misleto; others by hooks, as cleavers, burdock, houndstongue; and others are swallowed for the sake of the fruit, and voided uninjured, as the hawthorn, juniper, and some grasses: other seeds again are dispersed by means of an elastic seed-vessel, as oats, geranium, and impatiens: and the seeds of aquatic plants, and of those that grow on the banks of rivers, are carried many miles by the currents into which they fall.

mark, that they all dispose themselves so as to give the best protection to the young stems, flowers, buds, or fruit. The leaves of the tamarind-tree contract round the tender fruit, and protect it from the nocturnal cold. The Cassia or Senna, the Glycine, and many of the papilionaceous plants, contract their leaves in a similar manner. The leaves of the Chickweed, of the Asclepias, Atriplex, &c. are disposed in opposite pairs: during the night, they rise perpendicularly, and join so close at the top, that they conceal the flowers. The leaves of the Sida or Althæa Theophrasti, of the Ayenia, and Enothera, are placed alternately though horizontal, or even depending, during the day, at the approach of night they rise, embrace the stem, and protect the tender flowers. The leaves of the Solanum, or Night shade, are horizontal during the day; but, in the night, they rise and cover the flowers. The Egyptian Vetch erects its leaves during the night, in such a manner, that each pair seems to be one leaf only. The leaves of the White Lupine, in the state of sleep, hang down, and protect the young buds from being injured by the nocturnal air.

These and similar motions are not peculiar to the leaves of plants. The flowers have also the power of moving. During the night, many of them are inclosed in their calixes. Some flowers, as those of the German Spurge, Geranium Striatum, and common Whitlow-grass, when asleep, hang their mouths toward the earth, to prevent the noxious effects of rain or dew.

Linné has enumerated forty-six flowers, which possess this kind of sensibility: he divides them into three classes. (1) Meteoric flowers, which less accurately observe the hour of folding, but are expanded sooner or later according to the cloudiness, moisture, or pressure of the atmosphere. (2) Tropical

flowers, that open in the morning and close before evening every day; but the hour of their expanding becomes earlier or later as the length of the day increases or decreases. (3) Equinoctial flowers, which open at a certain and exact hour of the day, and for the most part close at another determinate hour.

In every copse, and sheltered dell,
Unveiled to the observant eye,
Are faithful monitors, who tell

How pass the hours and seasons by.

The green robed children of the spring
Will mark the periods as they pass,
Mingled with leaves time's feathered wing,
And bind with flowers his silent glass.

Mark where transparent waters glide,
Soft flowing o'er their tranquil bed;
There, cradled on the dimpling tide,
Nymphæa rests her lovely head.

But conscious of the earliest beam,
She rises from her humid nest,
And sees reflected in the stream
The virgin whiteness of her breast.

Till the bright day star to the west
Declines, in Ocean's surge to lave,
Then, folded in her modest vest,

She slumbers on the rocking wave.

See Hieracium's various tribe,

Of plumy seed and radiate flowers,
The course of Time their blooms describe,
And wake or sleep appointed hours.

Broad o'er its imbricated cup

The Goatsbeard spreads its golden rays,
But shuts its cautious petals up,
Retreating from the noon-tide blaze:

Pale as a pensive cloistered nun

The Bethlem star her face unveils,
When o'er the mountain peer the Sun,
But shades it from the vesper gales.

Among the loose and arid sands
The humble Arenaria creeps ;
Slowly the purple star expands,
But soon within its calyx sleeps.

And those small bells so lightly rayed
With young Aurora's rosy hue,
Are to the noon-tide Sun displayed,

But shut their plaits against the dew.
On upland slopes the shepherds mark
The hour, when, as the dial true,
Cichorium to the towering Lark

Lifts her soft eyes serenely blue.

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And thou, Wee crimson tipped flower,"
Gatherest thy fringed mantle round
Thy bosom, at the closing hour,

When nightdrops cathe the turfy ground.

Unlike Silene, who declines

The garish noontide's blazing light;
But when the evening crescent shines
Gives all her sweetness to the night.

Thus in each flower and simple bell,
That in our path untrodden lie,
Are sweet remembrancers who tell
How fast their winged moments fly.

CHARLOTTE SMITH.

The cause of those movements which constitute the sleep of plants, has been ascribed to the presence or absence of the sun's rays. In some of the examples I have given, the motions produced are evidently excited by heat. But plants kept in a hothouse, where an equal degree of heat is preserved both day and night, fail not to contract their leaves, or to sleep, in the same manner as when they are exposed to the open air. This fact evinces, that the sleep of plants is rather owing to a peculiar law, than to a quicker or slower motion of their juices.

The degrees of sensation in created objects deerease imperceptibly from man to the sea-nettle,

gall-insects, and what are called the most imperfect animal. Every vegetable, as well as the sensitive plant, shrinks when wounded. But, in most of them, the motion is too slow for our perception. When trees grow near a ditch, the roots which proceed in a direction that would necessarily bring them into the open air, instead of continuing this noxious progress, sink below the level of the ditch, then shoot across, and regain the soil on the opposite side. When a root is uncovered, without exposing it to much heat, and a wet sponge is placed near it, but in a different direction from that in which the root is proceeding, in a short time the root turns toward the sponge. In this manner the direction of roots may be varied at pleasure. All plants make the strongest efforts, by inclining, turning, and even twisting their stems and branches, to escape from darkness and shade, and to procure the influences of the sun. Place a wet sponge under the leaves of a tree, they soon bend downward, and endeavour to apply their inferior surfaces to the spunge. If a vessel of water be placed within six inches of a growing cucumber, in twentyfour hours the cucumber alters the direction of its branches, bends either to the right or left, and never stops till it comes into contact with the water. When a pole is placed at a considerable distance from an unsupported vine, the branches of which are proceeding in a contrary direction from that of the pole, in a short time, it alters its course, and stops not till it clings around the pole. But facts, of this kind, however they may excite our wonder, are far from proving that vegetables live, or that they are endowed with sensation, which implies a distinct perception of pleasure and pain: the whole may result from irritability which as before remarked, is a muscular property, common to animals and vegetables.

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