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times by the wind to great distances from the plant which produces them. It is the swelling also of this downy tuft within the seed-vessel, that seems to overcome the resistance of its coats, and to open a passage for the seed to escape.
But the constitution of seeds is still more admirable than either their preservation or their dispersion. In the body of the seed of every species of plant, ornearly of every one, provision is made for two grand purposes: first, for the safety of the germ ; secondly, for the temporary support of the future plant. The sprout, as folded up in the seed, is delicate and brittle, beyond any other substance. It cannot be touched without being broken. Yet, in beans, peas, grassseeds, grain, fruits, it is so fenced on all sides, so shut up and protected, that, whilst the seed itself is rudely handled, tossed into facks, shovelled into heaps, the miniature plant, the facred particle, remains unhurt. It is wonderful alf>, how long many kinds of seed, by the help of their integuments, and perhaps of their oils, stand out against decay. A grain of mustard feed has been known to lie in the earth for a hundred years; and, as soon as it had acquired a favorable situation, to shoot
as as vigorously as if just gathered from the plant. Then, as to the second point, the temporary support of the future plant, the matter stands thus. In grain, and pulse, and kernels, and pippins, the germ composes a very small part of the seed. The rest consists of a nutritious substance, from which the sprout draws its aliment for some considerable time after it is put forth; viz. until the fibres, shot out from the other end of the seed, are able to imbibe juices from the earth, in a sufficient quantity for its demand. It is owing to this constitution, that we see seeds sprout, and the sprouts make a considerable progress, without any earth at all. It is an œconomy also, in which we remark a close analogy between the seeds of plants, and the eggs of animals. The fame point is provided for, in the fame manner, in both. In the egg, the residence of the living principle, the cicatrix, forms a very minute part of the contents. The white, and the white only, is expended in the formation of the chicken. The yolk, very little altered or diminished, is wrapped up in the abdomen of the young bird, when it quits the shell; and serves for its nourishment, till it have learnt to pick its own food.
This persectly resembles the first nutrition of a plant. In the plant, as well as in the animal, the structure has every character of contrivance belonging to it: in both it breaks the transition from prepared to unprepared aliment: in both it is prospective and compenfatory. In animals which fuck, this intermediate nourish- ment is supplied by a different source*
In all subjects the most common observations are the best, when it is their truth and strength which have made them common. There are, of this fort, two concerning plants, which it falls within our plan to notice. The jirjl relates to, what has already been touched upon, their germination. When a grain of corn is cast into the ground, this is the change which takes place. From one end of the grain issues a green sprout; from the other a number of white fibrous threads. How can this be explained ? Why not sprouts from both ends? Why not fibrous threads from both ends? To what is the difference to be reserred, but to design; to the different uses which the parts are thereafter to serve; uses which discover themselves in the sequel of the process? The sprout, or plumule, struggles inro the air; and becomes the plant, of which,
from from the first, it contained the rudiments : the fibres shoot into the earth ; and, thereby, both fix the plant to the ground, and collect nourishment from the soil for its support. Now, what is not a little remarkable, the parts issue. ing from the seed take their respective directions, into whatever position the seed itself happens to be cast. If the seed be thrown into the wrongest possible position, that is, if the ends point in the ground the reverse of what they ought to do, every thing, nevertheless, goes on right. The sprout, after being pushed down a little way, makes a bend and turns upwards; the fibres, on the contrary, after shooting at'first upwards, turn down. Of this extraordinary vegetable fact, an account has lately been attempted to be given. "The plumule, it is faid, is stimulated by the air into action, and elongates itself when it is thus most excited: the radicle is stimulated by moisture, and elongates itself when it is thus most excited. Whence one of these grows upward in quest of its adapted object, and the other downward *." Were this account better verified by experiment than it is, it only shifts
* Darwin's Phytologia, p. 144.
2 c 2 the the contrivance. It does not disprove the contrivance ; it only removes it a little further back. Who, to use our author's own language, " adapted the objects ?" Who gave such a Quality to these connate parts, as to be susceptible of different "stimulation:" as to be ** excited" each only by its own element, and precisely by that, which the success of the vegetation requires? I fay, " which the success of the vegetation requires," for the toil of the husbandman would have been in vain; his laborious and expensive preparation of the ground in vain; if the event must, after all, depend, upon the position in which the scattered seed was sown. Not one seed out of a hundred would fall in a right direction. 'M Our second observation is upon a general property of climbing plants, which is strictly mechanical. In these plants, from each knot or joint, or, as botanists call it, axilla of the plant, issue, close to each other, two shoots; one, bearing the flower and fruit, the other, drawn out into a wire, a long, tapering, spiral tendril, that twists itself round any thing which lies within its reach. Considering, that, in this class, two purposes are to be provided for, (and together,) fructification and support,