world would have quickly been reduced to a barren and lifeless waste. But there is nothing more remarkable in the constitution both of the vegetable and animal worlds, than the careful provision which has been made for preventing this catastrophe, not only as respects organic life in general, but as respects each distinct kind of organized existence, which the plastic hand of the Creator has formed. All are endowed with an ample, and even redundant capacity of giving rise to offspring of their own species. The manner in which this is almost uniformly effected in the vegetable world, as I formerly stated, is by means of seeds, which they propagate in various forms, preserve by various contrivances, and scatter over the soil in various ways, and which are by their peculiar conformation and properties, as will afterward be seen, most curiously and skilfully adapted to the functions they are destined to perform.

The properties we have mentioned are common to all, or, at least, to by far the greater part of terrestrial plants; and the remarkable uniformity which exists in their general structure, is a clear indication of One Contriving Mind. But the law of diversity is not less remarkable in their formation, than the law of coincidence and analogy. There are certain definite objects to be accomplished by each species, and, in them all, there is a striking conformity of type; and yet, amidst this uniformity both of intention and of original model, there exists a variety at once interesting and surprising. This is the case not merely in the vegetable but animal world, in a degree which is exceedingly remarkable, even on the slightest inspection, and which grows upon us as it is contemplated. "In every department of nature," says Mr Kirby, from whose work the facts contained in this paper, are drawn, “it cannot fail to strike us, that boundless variety is a characteristic and predominant feature of her productions. It is only when the object to be attained, is dependant on certain definite conditions, excluding the possibility of modification, that

these conditions are uniformly and strictly adhered to. But wherever that absolute necessity does not exist, and there is afforded scope for deviation, there we are certain to find introduced all those modifications, which the occasion admits of. Not only is this tendency to variety exemplified in the general appearance and form of the body, but it also prevails in each individual organ, however minute and insignificant that organ may seem. Even when the purpose to be answered is identical, the means which are employed are infinitely diversified in different instances, as if a design had existed of displaying to the astonished eyes of mortals, the unbounded resources of Creative power. While the elements of structure are the same, there is presented to us, in succession, every possible combination of organs, as if it had been the object to exhaust all the admissible permutations in the order of their union."

SECOND WEEK-THURSDAY.

PRESERVATION AND DISTRIBUTION OF SEEDS.

I YESTERDAY stated, that the chief method, by which the Author of Nature has provided for the reproduction of plants, is by means of seeds. This method may be considered as universal, for there is no perfect plant which is not produced by means of a seed; although other methods, also, are sometimes employed, such as propagation by means of runners or off-sets, or by the rooting of branches. Seeds, as I have already noticed, resemble, in some remarkable particulars, the eggs of fowls and insects; and, in the same analogy, the spawn of fish may also be included,—thus exhibiting one of those features, by which the various orders of organized beings appear to be so mysteriously related, and in which we trace so unequivocally the handiwork of a common Creator.

There are many tribes of vegetables, which, from year to year, depend entirely for their reproduction on seeds. The plant having given birth to this embryo of its species, and deposited it in the soil, withers down to the root, and expires. Now, let us look at this curious production. It is composed of various parts, named cotyledons, or corcle, membranes, and vessels. The cotyledons are composed of a cellular network, curiously organized, which forms the substance of the seed, and contains the albuminous matter, which nourishes the young plant in the earlier stages of its existence. The corcle is the embryo of the future plant, and lies between the cotyledons; it differs in its structure at different stages, consisting at first of a thin glary fluid, and afterward becoming more concrete and regularly organized, till at last it displays the rudiments of the root and of the plumale, or future stalk. We have named the seeds of plants, vegetable eggs; and every one must observe in this description, a remarkable similarity between the eggs of animals and these productions of an inferior kingdom; and this remarkable resemblance to the animal embryo, is still further exhibited in the existence of an umbilical cord, which attaches to the seed till it be perfectly ripe, and through which it receives its nourishment from the parent plant.

These seeds, when it is intended that they shall lie dormant, in a temperate climate, through the winter, to reproduce the species in spring, are furnished with every property necessary for the intended purpose. They remain in the bosom of the ground, sometimes protected by peculiar contrivances to preserve them from the severity of the season; but, whether this be the case or not, always endowed with qualities, or subject to conditions, which are sufficient for the preservation of the species, being, generally speaking, uninjured by the cold and wet, and unaffected by the alternations of comparative heat and cold, till the genial season of spring returns, when they can extend their roots, shoot forth their plu

males, raise their foot-stalks, and unfold their tender leaves with impunity.

We have already observed, that this mode of propagating the species is universal: It belongs to all the various orders of plants, whether herb, shrub, or tree, and whether annual, biennial, or perennial. Some of these species preserve their seed in the pod, through the winter months, and others both produce and scatter their seed in the early part of the vegetating season, so as to give rise to the seedling, or the full grown plant, before the cold weather, which ends the year, has set in. These varieties, in the manner in which the seed is employed, occasion the necessity of varieties, also, in the mode of propagation, which are abundantly curious and admirable. Some seeds are enclosed in shells, others in purses; some are lodged in capsules, some in wooden sheaths; and others again are placed deep in the heart of fruit, which serves at once for their protection and nutriment, and, in some instances, perhaps, also for a rich and appropriate manure, as it decays on the surface of the earth.

In speaking of fruit, as the means by which the seed is frequently shielded, I do not forget, that this very fruit forms the food of various animals; and this gives rise to another proof of Creative contrivance; for while the food itself is digested, and affords nourishment to the animal, the seed in many instances is voided uninjured, and perhaps better prepared for vegetation; and it is thus that the Creator has provided for the dissemination of various plants, and even for their transportation to islands, and other localities, which they could not otherwise reach.

This leads me to state, that, if some provision were not made for the dissemination of plants, they would seldom be far removed from the locality of the parent. Contrivances, therefore, for this purpose, were requisite, and they are many and singular. Numerous seeds, for example, are furnished with an elastic pod, which, on

bursting, projects its contents to a considerable distance. Of this we have a well-known example in the common furze. Nearly all the seeds of compound flowers are provided with a species of wings, through which means they are conveyed, by the wind, to distant places. The thistle and dandelion are of this kind. Other seeds, as the bur, are scattered abroad, by laying hold, by means of hooks, on passing animals; and not only do birds and some quadrupeds perform, as we have stated, an important part in this useful office, by swallowing the seeds contained in berries, but some animals, both of the insect and larger orders, contribute to the same end, by their storing instincts. Nor must we forget the effects of streams and rivers in the accomplishment of this useful intention. So various and so wise are the means by which the Creator accomplishes this beneficent purpose.

To all this I must add the power, with which the Author of Nature has endowed various seeds, of retaining the vital principle for a lengthened period. Ray mentions, that, after the great fire in London in 1666, a plant (Sisymbrium iris), the seeds of which must have lain dormant for several hundred years, covered, to an amazing extent, the walls of the buildings which had been burned.* The seeds which are sometimes discovered

* The following observations on this curious subject, are extracted from a notice in Professor Jameson's Philosophical Journal, for the quarter ending January 1836. "Spontaneous Plants.-Few things are more extraordinary than the unusual appearance and development of certain plants, in certain circumstances. Thus, after the great fire in London, in 1666, the entire surface of the destroyed city was covered with such a vast profusion of a species of cruciferous plant, the Sisymbrium iris of Linnæus, that it was calculated that the whole of the rest of Europe could not contain so many plants of it. It is also known, that, if a spring of salt water makes its appearance in a spot, even a great distance from the sea, the neighbourhood is soon covered with plants peculiar to a maritime locality, which plants, previous to this occurrence, were entire strangers to the country. Again, when a lake happens to dry up, the surface is immediately usurped by a vegetation, which is entirely peculiar, and quite different from that which flourished on its former banks. When certain marshes of Zealand were drained, the Carex cyperoides was observed in abundance; and it is known, that this is not at all a Danish plant, but peculiar to the north of Germany. In a work upon the Useful Mosses, by M. de Brebisson, which has been announced for