positions and combinations by some thinking, willing, and competent agent, for the express purpose of their being thereby made to be the artificial figure and individual things which we see them respectively to be, and of doing the precise and determinate actions and effects which each of them separately and peculiarly perform. Such are organizations in general: and plants are that peculiar species of their construction which display to us the Divine ideas in this class of natural being; and which form the largest compartment in the immense panorama of the surface of our terrestrial fabric.

Without affirming a plant to be a real animal, as some of the Grecian philosophers imagined,* we shall best understand its true nature and construction, by considering it as an animal in the principle of its systematic form; but without being sentient or intelligent; and differing also in one essential point in the matter of its composition. They are distinguished also by another general peculiarity in their material nature. Animal bodies seem, by some interior though yet unknown process, to produce lime‡-plants, never; but these, as their appropriate function, appear to generate carbon instead. The absence of any intellectual quality

* Plutarch remarks, that Plato, Anaxagoras, and Democritus thought vegetables to be earthly animals. So did Empedocles. But Aristotle, while he granted to them life like animals, denied their being such, because these have appetite, sense, and reason, in which plants are deficient. Plut. Plac. Phil. c. 26.

†This distinction in the material substance is, that azote is an invariable part of the compound of all animals, but not of plants; while carbon is the characteristic of the latter. On burning either, the azotic smell immediately marks the animal. "The most essential of the compounds of vegetables are carbon, oxygen, and hydrogen merely. A small proportion of nitrogen, or azote, is said to be formed only in cruciform plants."-London Encyc. Gard. 193.

I cannot but concur, according to our present knowledge, with Dr. Macculloch, that "the solid spoils of animals, chiefly marine, constitute limestones at present; and have produced them, at distant and different periods; nor, for those of the present times, is there any other origin than animal chymistry."-Maccul. Geology, vol. ii. p. 414. We see one species of this matter in daily formation now by the coral insects; and other kinds in the eggs of birds, in the bones of all animals, in the chalkstones of the human hands and feet, and in the frequent ossification of our vascular system.

Dr. Macculloch rightly intimates, that it is less safe to infer "that there is no other origin for carbon than vegetable chymistry."-Ib. p. 414. This is truly said, because there appears to be a carbon in the ancient rocks of the earth, which must have receded vegetation. But that

makes their principle of life to be very dissimilar to, or at least very distinct from, that of animals.*

Most vegetables have an upright body, with vessels ascending and communicating with each other, as in us, but with sap instead of blood; with woody fibres, instead of bone; with pith, instead of brain and nerve; with bark or rind, instead of skin or hide. Their leaves imbibe air, as we breathe it, and also light and moisture; and in their continual motion answer the purposes of our respiration and exercise. They also imbibe and expire an aerial fluid, as we do, though with this difference, that they emit oxygen gas, under the influence of the solar rays, while animals absorb and retain it. They require food, as we do, but

plants convert some of their nutritive fluids into carbon, has every evis dence of being a general fact.

*Haller considered plants to possess spontaneous motion, to exhibit evident marks of irritability, and to obey the operation of stimulants but that they had no nerves. M. Gæppert found that narcotic poison did not affect them, but a drop of prussic acid put on a flower caused an immediate motion of its stamina to the pistillum. The stamina of the common barberry contract on the touch of an insect or strange body.Bull. Univ. 1830, p. 264. But this may be an electrical effect, which the movements of the sensitive plant seem to be. M. Poiteau says, that a seed always polarizes itself in its germination. Its radicle becoming one of its poles, and the plumula the other. Electricity may cause this. There are 34 families of plants which are voluble: they are chiefly in the torrid zone, and make one turn in 24 hours.-Bull. Univ. 1829, p. 69. But this seems to be a physical action of the light or sun, as the closing and opening of the tulip, the daisy, and the convolvulus are. M. Morren ascribes the motion of the zoocarpes to the effect of electrical disengage ment. Ib. 1830, p. 260.

Gardeners have an impression that the orchis latifolia walks, as it never keeps to the place where it is put; and Bosc admitted its walking; but M. Morren found, on examination, that it was an oscillation of two alternate bulbs, and not an actual progression.-Ib.

"Linnæus thought the PITH to be the seat of life and source of vegeta tion. There is, in certain respects, an analogy between the medulla of plants and the nervous system of animals. It is no less assiduously protected than the spinal marrow, or principal nerve. It is branched off

and diffused through the plant, as nerves are through the animal. Mr. Lindsey thought he demonstrated the medulla in the sensitive plant to be the seat of irritability. I cannot but incline to the opinion that it is a reservoir of vital energy, even in the bulbous grasses."-Sir J. Smith, Introd. 40-42.

"It is agreed that, in the daytime, plants imbibe from the atmo sphere carbonic acid gas; that they decompose it, absorb the carbon as matter of nourishment, which is added to the sap, and emit the oxygen. This same gas they absorb from water when it is separated from that fluid by the action of light.....In the dark, plants give out carbon and absorb oxygen."-Smith, ib. 212, 213. H

their roots are their mouths. They have not, like quadrupeds, a particular stomach and hepatic system for its digestion; but, like some of the lower animals, they have a power of assimilating and converting what they take into their own substance, without these functions.* But all vegetables are fixed in their place of growth; they have no locomotive power. Where they are born they live and die. This circumstance would alone make them a peculiar class of beings, if they had every other similitude to animal existences. They are living beings, but with no power of spontaneous moveability from their first station of development.†

The seed contains the embryo plant in the little corculum, which all, on being carefully opened, display. It is familiarly called the heart of the walnut-the little figure at one end of all nuts and kernels. Vessels extend from this to the substance in which it lies, which has received the name of cotyledon. If this be single, as in the grasses and corn, it is a monocotyledon seed and plant; if, as in the larger herbs and trees, it consists of two lobes, they are

* With respect to those minute and simply-constructed animals, the polypes and the lower tribes of worms, their feelers, put forth into the water, seem scarcely different from roots seeking their food in the earth. Some of these may be turned inside out, like a glove, without any disturbance of their ordinary functions."-Smith, ib. p. 3.

†The vegetables that swim and live in water unattached to any soil, and which are nourished by what they float in, do not move themselves. They only follow the impulse of the stream. Nor has the curious AIRPLANT of China more self-motivity from not being fixed to any earth, but living in and on the air and light. It has the same want of locomotivity. This singular vegetable has been thus mentioned :-

"Epidendron, flos aeris, a plant indigenous in China; famous for the beauty of its flowers and the sweetness of its perfume. It lives only on air. The Chinese suspend it round the ceiling of their rooms. Prince Leopold obtained a branch three feet along. It had some hundreds of large scarlet and yellow flowers."-Bull. Üniv. 1829, p. 167.

"There is a tribe of plants, called monocotyledons, characterized by having only one lobe to the seed. To these belong the natural order of palms, which being the most lofty, and, in some instances, the most long-lived of plants, have justly acquired the name of trees. Yet they are rather perennial herbaceous plants, having nothing in common with the growth of trees in general. The palms are formed of successive crowns of leaves which spring directly from the root. The common orange lily and white lily belong to the same natural family of monocotyledons. Their stems, though only of annual duration, are formed nearly on the same principle as a palm; and are really congeries of leaves rising one above another, and united by their bases into an apparent stem."-Smith's Int. Bot p. 59.

called dicotyledons ;* if no such are discernible at all, they are termed acotyledon plants,† which in some, and perhaps in most, countries are the most numerous.‡ All plants consist of two substances, vessels and cellular tissue. In general language, what is not one may be deemed the other. But for the delineation of the various parts of their mechanical structure, I would refer you to the latest publications of our scientific botanists. I shall only notice their more remarkable properties, which illustrate the principles and purposes of their Creator.

Their growth and nutrition.—The seed of plants resembles the animal ovum or egg. The embryo in both is at one end, with vessels ramifying into the rest of the substance, and deriving from that its first nutriment. The access of a certain degree of heat is necessary to begin the activity and development in both; and when that occurs to the seed, in a proper soil and place, and with sufficient moisture, vegetation begins. The cotyledons swell and rise in the seminal leaves. The corculum lengthens downwards in the germ of the radicle, and its upper part ascends in the plumula. A nutritious matter passes from the seminal leaves to the radicle, which daily elongates. The process of vegetation, thus beginning from the cotyledons, steadily proceeds under its subsequent nourishment from the earth and air, until the perfect plant is formed.]

* M. Desfontaines has made an important discrimination: "Plants in which the bark, wood, and pith, are distinct, spring from seeds with two lobes, or dicotyledons. Those where these are blended, form the monocotyledons."

"Some think that all acotyledon plants, as mushrooms, mosses, &c. are entirely composed of cellular tissue, without vessels; and that monocotyledons have the cellular and vascular systems blended together through the entire stem; while all the dicotyledons have the two systems BO symmetrically arranged, that the bark, wood, and pith are always distinguishable from each other."-Edinb. Rev. No. 99, p. 154.

Thus in Denmark "The cotyledon plants amount to 1600; and the acotyledon ones to 3200."-Bull. Univ. 1830, p. 269.

"We then see a white eylindrical body develop at this point, while the embryo of the plumula remains stationary. From the end of this white body the radicle issues; and soon penetrating the earth, attracts the fluids which make its lymph."-M. Feburier. Bull. Univ. 1830, p. 74.

"This lymph, by mixing with the nutritive substance that descends from the seminal leaves, forms the sap, which ascends to the plumula. Thus, the seminal leaves may be deemed the upper points of the roots of the plant, with which they have a direct communication by the stalk which separates them. The radicle is fixed in a contrary sense to the leaves, be

Nothing is more curious in nature than the persevering efforts made by the living principle in plants to force their radicle downwards; whatever efforts may be made to give it another direction are constantly baffled by the growing power, which knows where its nutrition lies, and will go rightly to seek it. No animal can display a more persisting volition.* Yet when circumstances become such, that its food is not downwards, but upwards, it will then, and then only, rest in that inverted and ascending position.† Earth is not so essential to vegetable growth as moisture; for even trees will grow in water only.‡ Earth is but the bed in which the vegetable nutriment is best prepared and presented to the absorbing roots. This is now stated to be an oxyde of carbon or humic acid, made by a chymical union with water, and which forms that humus or soil that most occasions or promotes vegetation. Without this vegetable

cause the bundles of fibres which produce it, and the lymph which makes its first nourishment, descend from the cotyledons."-Feburier, ib.

"The young root is the first part of the infant plant that comes forth; and by an unerring law of nature it is sent downwards, to seek out nourishment, as well as to fix the plant in the ground. In whatever position seeds happen to lie in the earth, the root makes more or less of a curve, in order to shoot downwards. Mr. Hunter sowed a number of seeds in a basket of earth placed on an axis, by which their position was a little altered every day. After the basket had thus made two or three circumvolutions, the young roots were found to have formed as many turns, in attempting to attain their natural perpendicular direction." Smith, Introd. p. 95.

† Dr. Walker remarks, "The ascent of the plume and the descent of the radicle is surprising. It is not merely to ascend or descend, but the endeavour of the one is to get into the air, and of the other into the earth. For, if placed to the roof of a cave, or in an inverted flower-pot, then, as I have often seen, the radicle ascends and the plume descends, the one to the earth above it the other to the air below it."-Woodh. Lord Kames, vol. ii. Ap. p. 64.

"Du Hamel reared in water, plants of the horse-chestnut and almond to some considerable size, and an oak till it was eight years old; but they made less and less progress every year. Their roots were found to be in a very bad state, and they died.-Loudon, Encyc. Gard. 197..... Plants, though vegetating merely in water, do yet augment the quantity of their carbon."-Ib..... Plants seem to have a mysterious power of making carbon, which may account for their growing a while in water only,

Dr. Sprengel expresses this principle. His ideas are, that the humic acid and humates become the nutritive principles of plants; that they are formed at first from the soft parts of plants, and afterward from the dissolution of their fibres; that in their decomposition, one part of their carbon combines with the oxygen of the air, and produces carbonic acid, which separates itself; and also the humic acid, which combines chymis