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nourishment from the soil for its support. Now, what is not a little remarkable, the parts issuing 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 said) 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 experi. ment than it is, it only shifts the contrivance. It does not disprove the contrivance; it only removes it a little farther 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 say,
or which the success of the vegetation requires :" for the toil of the husband. man 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 hun. dred would fall in a right direction.
Our second observation is upon a general property of
• Darwin's Phytologia, p. 144.
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, the fruitage of the plant, and the sustentation of the stalk, what means could be used more effectual, or, as I have said, more mechanical, than what this structure presents to our eyes ? Why, or how, without a view to this double purpose, do two shoots, of such different and appropriate forms, spring from the same joint, from contiguous points of the same stalk? It never happens thus in robust plants, or in trees. " We see not (says Ray) so much as one tree, or shrub, or herb, that hath a firm and strong stem, and that is able to mount up and stand alone without assistance, furnished with these tendrils." Make only so simple a comparison as that between a pea and a bean. Why does the pea put forth tendrils, the bean not; but because the stalk of the pea cannot support itself, the stalk of the bean can? We may add also, as a circumstance not to be overlooked, that in the pea tribe, these clasps do not make their appearance till they are wanted; till the plant has grown to a height to stand in need of support.
This word as support” suggests to us a reflection upon a property
and canes. The hollow stems of these classes of plants are set, at certain intervals, with joints. These joints are not found in the trunks of trees, or in the solid stalks of plants. There
may be other uses of these joints; but the fact is, and it appears to be, at least, one purpose designed
by them, that they corroborate the stem; which, by its length and hollowness, would otherwise be too liable to break or bend.
Grasses are Nature's care. With these she clothes the earth ; with these she sustains its inhabitants., Cattle feed upon their leaves; birds upon their smaller seeds; men upon the larger : for, few readers need to be told that the plants, which produce our bread-corn, belong to this class. In those tribes which are more generally considered as grasses, their extraordinary means and powers of preservation and increase, their hardiness, their almost unconquerable disposition to spread, their faculties of reviviscence, coincide with the intention of nature concerning them. They thrive under a treatment by which other plants are destroyed. The more their leaves are consumed, the more their roots increase. The more they are trampled upon, the thicker they grow. Many of the seemingly dry and dead leaves of grasses revive, and renew their verdure, in the spring. In lofty mountains, where the summer heats are not sufficient to ripen the seeds, grasses abound which are viviparous, and consequently able to propagate themselves without seed. It is an observation, likewise, which has often been made, that herbivorous animals attach themselves to the leaves of grasses ; and, if at liberty in their pastures to range and choose, leave untouched the straws which support the flowers*
The GENERAL properties of vegetable nature, or properties common to large portions of that kingdom, are almost all which the compass of our argument allows to bring forward. It is impossible to follow plants into their several species. We may be allowed, low
Withering, Bot. Arr. vol. i. p. 28, ed. 2d.
ever, to single out three or four of these species as worthy of a particular notice, either by some singular mechanism, or by some peculiar provision, or by both.
I. In Dr. Darwin's Botanic Garden (1. 395. note), is the following account of the vallisneria, as it has been observed in the river Rhone." They have roots at the bottom of the Rhone. The flowers of the female plant float on the surface of the water, and are furnished with an elastic, spiral stalk, which extends or contracts as the water rises or falls; this rise or fall, from the torrents which flow into the river, often amounting to many feet in a few hours. The flowers of the male plant are produced under water; and, as soon as the fecundating farina is mature, they separate themselves from the plant; rise to the surface; and are wafted by the air, or borne by the currents, to the female flowers." Our attention in this narrative will be directed to two particulars: first, to the mechanism, the "elastic, spiral stalk," which lengthens or contracts itself according as the water rises or falls; secondly, to the provision which is made for bringing the male flower, which is produced under water, to the female flower which floats upon the surface.
II. My second example I take from Withering's Arrangement, vol. ii. p. 209. ed. 3.
" The cuscuta europea is a parasitical plant. The seed opens, and puts forth a little spiral body, which does not seek the earth, to take root; but climbs in a spiral direction, from 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 evergreen 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; 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 (colchicum 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 ne. glected, Nature has gone out of her course to provide for its security, and to make up to it for all its defects. The seed-vessel, which in other plants is situated within the cup of the flower, or just beneath it, in this
* Withering, Bot. Arr. vol. i. p. 203, ed. 2d,