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He is mine, said Affliction; I gave him his birth,
I alone am his cause of creation :
The materials were furnished by me, answer'd Earth ;-
The gods, all assembled in solemn Divan,
Let Affliction possess her own child, till the woes
After death give his body to Earth, whence it rose ;
WALKS IN THE GARDEN.-No. III.
"The life and felicity of an excellent gardener is preferable to all other diversions." EVELYN.
"What could I wish that I possess not here?
Health, leisure, means to improve it, friendship, peace,
To me the branches of the trees always appear to stretch themselves out and droop their leaves with an obvious sense of enjoyment, while they are fed by the renovating moisture of a shower. I have been complacently watching my shrubs and plants during this repast; but the rain is now over, they have finished their meal, and as they have already begun with fresh spirits to dance in the breeze and glitter in the sunshine, let us sally forth to share their festivity. What a delicious fragrance gushes from the freshened
grass and borders! It is the incense which the grateful earth throws up to heaven in return for its fertilising waters. Behold! here is one of the many objects which the shower has accomplished: by moistening the wings of the flying Dandelion, it has conveyed it to the earth at the very moment when it was best adapted for the reception of its seed. "The various modes by which seeds are dispersed, cannot fail to strike an observing mind with admiration. Who has not listened in a calm and sunny day to the crackling of furze bushes, caused by the explosion of their little elastic pods; or watched the down of innumerable seeds floating on the summer breeze, till they are overtaken by a shower, which, moistening their wings, stops their further flight, and at the same time accomplishes its final object, by immediately promoting the germination of each seed in the moist earth? How little are children aware, as they blow away seeds of Dandelion, or stick burs in sport upon each other's clothes, that they are fulfilling one of the great ends of nature !"* The various mechanism and contrivances for the dissemination of plants and flowers are almost inexhaustible. Some seeds are provided with a plume like a shuttlecock, which, rendering them buoyant, enables them to fly over lakes and deserts; in which manner they have been known to travel fifty miles from their native spot. Others are dispersed by animals; some attaching themselves to their hair or feathers by a gluten, as Misletoe; others by hooks,
* Smith's Introduction to Botany, p. 302.
as Burdock and Hounds-tongue; and others are swallowed whole, for the sake of the fruit, and voided uninjured, as the Hawthorn, Juniper, and some grasses. Other seeds again disperse themselves by means of an elastic seed-vessel, as Oats and Geranium; and the seeds of aquatic plants, and those which grow on the banks of rivers, are carried many miles by the currents into which they fall. The seeds of Tillandsia*, which grows on the branches of trees like Misletoe, are furnished with many long threads on their crowns, which, as they are driven forwards by the winds, wrap round the arms of trees, and thus hold them fast till they vegetate. When the seeds of the Cyclamen are ripe, the flower-stalk gradually twists itself spirally downwards till it touches the ground, and forcibly penetrating the earth, lodges its seeds, which are thought to receive nourishment from the parent root, as they are said not to be made to grow in any other situation. The subterraneous Trefoil has recourse to a similar expedient, which however may be only an attempt to conceal its seeds from the ravages of birds; while the Trifolium globosum adopts a still more singular contrivance: its lower florets only have corols, and are fertile; the upper ones wither into a kind of wool, and, forming a head, completely conceal the fertile calyxes. But the most curious arrangement for vegetable locomotion is to be found in the awn or beard of Barley, which, like the teeth of a saw, are all turned towards one end of it:
* Darwin's Loves of the Plants, canto 1.
as this long awn lies upon the ground, it extends itself in the moist air of night, and pushes forward the barley-corn which it adheres to; in the day it shortens as it dries, and as these points prevent it from receding, it draws up its pointed end, and thus, creeping like a worm, will travel many feet from its parent stem. The late Mr. Edgeworth constructed a wooden creeping hygrometer upon this principle, which expanding in moist weather, and contracting itself when it was dry, in a month or two walked across the room which it inhabited.
If Nature have been thus ingenious in providing for the dispersion of seeds, she has not been less provident in her arrangements for procuring a prolific and inexhaustible supply. Her great leading principle seems to be eternal destruction and reproduction, which one of our essayists tells us may be simplified into the following concise order to all her children, "Eat and be eaten." She has been not less prodigal in the seeds of plants than in the spawn of fish; as almost any one plant, if all its seeds should grow to maturity, would in a few years alone people the terrestrial globe. The seeds of one Sunflower amount to 4000; Poppy has 32,000. Mr. Ray asserts that 1012 seeds of Tobacco weighed only one grain, and that thus calculated, they amounted in one plant to 360,000; and he supposes the seeds of the Ferns to exceed a million on a leaf! Nor does this exuberance seem necessary to counteract their small tenacity of life; for, on the contrary, the vital principle in seeds is generally preserved with a remarkable vigour. Great
degrees of heat, short of boiling, do not impair their vegetative power, nor do we know any degree of cold which has such an effect. They may be sent round the world, exposed to every variety of climate, without injury; and even when buried for ages deep in the ground, they retain their vitality, although they will not germinate, apparently from the want of some action of the air, as it has been ascertained by repeated experiments that seeds planted in the exhausted receiver of an air-pump will not vegetate. The earth thrown up from the deepest wells, although all possible access of fresh seeds be carefully excluded, will, upon exposure to the air, shoot forth weeds, grasses, and wild flowers, whose seeds must have lain dormant for many centuries; and it is very common, upon digging deeper than usual in gardeners' grounds, to recover varieties of flowers which had long been lost.
Observe in this beautiful double Dahlia how highly nature may be improved, all double flowers being produced by cultivation, although their reproductive powers are frequently lost in the process; whence they have been termed by botanists vegetable monsters. This operation is effected in various ways: in some the petals are multiplied three or four times, without excluding the stamens, whence they are able to produce seeds, as in Campanula and Stramonium; but in others the petals become so numerous, as totally to exclude the stamens, and these are, of course, unproductive. In some, the nectaries are sacrificed for the formation of petals, as in Larkspur; while in others,