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Icn, fired from the antheræ into the cup of the flower, is catched in its descent by the head of the pistil, called the stigma. But how is this managed when the flowers hang down, (as does the crown imperial, for instance,) and in which position, the farina, in its fall, would be carried from the stigma, and not towards it? The relative length of the parts is now inverted. The pistil in these flowers is usually longer, instead of shorter, than the stamina, that its protruding summit may receive the pollen as it drops to the ground. In some cases, (as in the nigella,) where the ghosts of the pistils or styles are disproportionably long, they bend down their extremities upon the antheræ, that the necessary approximation may be effected.
But (to pursue this great work in its progress,) the impregnation, to which all this machinery relates, being completed, the other parts of the flower fade and drop off, whilst the gravid seed-vejsel, on the contrary, proceeds to increase it« bulk, always to a great, and in some species (in the gourd, for example, and melon,) to a surprising comparative size; assuming in different plants an incalculable variety of forms, but all evidently conducing
to to the security of the seed. By virtue of this process, so necessary, but so diversified, we have the seed, at length, in stone fruits and nuts, incased in a strong shell, the shell itself inclosed in a pulp or husk, by which the seed within is, or hath been,sed; or, more generally (as in grapes, oranges, and the numerous kinds of berries,) plunged overhead in a glutinous syrup, contained within a skin or bladder: at other times (as in apples and pears) embedded in the heart of a firm fleshy substance; or (as in strawberries) pricked into the surface of a soft pulp.
These and many more varieties exist in what we call fruits *. In pulse, and grain,
* From the conformation of fruits alone, one might be led, even without experience, to suppose, that part of this provision was destined for the utilities of animals. As limited to the plant, the provision itself seems to go beyond its object. The flesh of an apple, the pulp of an orange, the meat of a plum, the "satnessof the olive," appear to be more than sufficient for the nourishing of the seed or kernel. The event shews, that this redundancy, if it be one, ministers to the support and gratification of animal natures: and when we observe a provision to be more than sufficient for one purpose, yet wanted for another purpose, it is not unfair to conclude that both purposes were contemplated together. It favors this view of the subject to remark, that fruits are not (which they might have been) ready all together, but that they ripen in succession throughout a great part of the
year} and grasses; in trees, and shrubs, and flowers; the variety of the seed-vessels is incomputable. We have the seeds (as in the pea tribe) regularly disposed in parchment pods, which, though soft and membranous, completely exclude the wet even in the heaviest rains; the pod also, not seldom (as in the bean) lined with a fine down; at other times (as in the senna) distended like a blown bladder: or we have the seed enveloped in wool (as in the cotton plant), lodged (as in pines) between the hard and compact scales of a cone; or barricadoed (as in the artichoke and thistle) with spikes and prickles; in mushrooms, placed under a penthouse; in ferns, within flits in the back part of the leaf ; or (which is the most general organization of all) we find them covered by strong, close, tunicles, and attached to the stem according to an order appropriated to each plant, as is seen in the several kinds of grain, and of grasses.
year; some in sunhnerl some in autumn; that some require the flow maturation of the winter, and supply the spring: also that the coldest; fruits grow in the hottest places. Cucumbers, pine apples, melons, are the natural produce of warm climates, and contribute greatly, by their coolness, to the refreshment of the inhabitants of those countries.
In In which enumeration what we have first to notice is, unity of purpose under variety of expedients. Nothing can be more Jingle than the design; more diversified than the means. Pellicles, shells, pulps, pods, husks, skins,, scales armed with thorns, are all employed in prosecuting the fame intention. Secondly; we may observe, that, in all these cases, the purpose is fulfilled within a just and limited degree. We can perceive, that, if the seeds of plants were more strongly guarded than they are, their greater security would intersere with other uses. Many species of animals would suffer, and many perish, if they could not obtain access to them. The plant would overrun the foil; or the seed be wasted for want of room to sow itself. It is, sometimes, as necessary to destroy particular species of plants, as it is, at other times, to encourage their growth. Here, as in many cases, a balance is to be maintained between opposite uses. The provisions for the preservation of seeds appear to be directed, chiefly against the inconstancy of the elements, or the sweeping destruction of inclement seasons. The depredation of animals, and the injuries of accidental violence, are allowed for in the
abundance abundance of the increase. The result is, that, out of the many thoufand different plants which cover the earth, not a single species, perhaps, has been lost since the creation.
When nature has persected her seeds, her next care is to disperse them. The seed cannot answer its purpose, while it remains confined in the capsule. After the seeds therefore are ripened, the pericarpium opens to let them out; and the opening is not like an accidental bursting, but, for the most part, is according to a certain rule in each plant.What I have always thought very extraordinary, nuts and shells, which we can hardly crack with our teeth, divide and make way for the little tender sprout which proceeds from the kernel. Handling the nut, I could hardly conceive how the plantule was ever to get out of it. There are cases, it is faid, in which the seed-veflel by an elastic jerk, at the' moment of its explosion, casts the seed to a distance. We all however know, that many feeds (those of most composite flowers, as of the thistle, dandelion, &c.) are endowed with what are not improperly called wings; that: is, downy appendages, by which they are^n- i abled to float in the air, and are carried often-..