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the fruitage of the plant, and the sustentation of its stalk, what means could be used more effectual, or, as I have faid, more mechanical, than what this structure presents to cur eyes? Why or how, without a view to this double purpose, do two shoots, of such different and appropriate forms, spring from the fame joint, from contiguous points of the fame stalk? It never happens thus in robust plants, or in trees. "We see not," fays 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, furnifoed .zvitb these tendrils" Make only so simple a comparison as that between a pea ^nd 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. t
This word " support," suggests, to us a reflection upon a. property of grasses, of corn, and canes. The hollow stems of these glasses of -slants, are set, at certain intervals, with a c 3 , joints. 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.
Grafts are Nature's care. With these she clothes the earth: with these she sustains its inhabitants. Cattle seed upon their leaves; birds upon their smaller seeds; men upon the larger; for few readers need 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, however, 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, line 395, hole, is the following account of the vallisrieria, as it has been observed in the river Rhone. ** They have roots at the bottom of the Rhone. The flowers of the female plant
* With. Botr Apr. vol i. p. rt,ed. pi,
2 c 4 float float on the surface of the water, and are furnished with an elastic,spiral, Jlatk, 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 wasted 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. Arrang. vol, ii. p. 209. ed. 3. "The cuscuta curopœa 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 Yeflels, it draws its nourishment." The
« little "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 mijseltoe. 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 defeat 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 their seeds, insinuate their fibres into the woody substance of the tree; and the event is, that a misseltoe plant is produced the next winter". Of no other plant do the roots refuse to shoot in the ground; of no other plant do the seeds pof
* Ib. p. 203.