The sponge also belongs to this class of strange animal substances; it consists of a fibrous mass, containing a jelly-like substance. which when touched, discovers a slight sensation, the only sign of life manifested by it. There are many species of sponge; those most valued in the arts are found in the Mediterranean sea and Indian ocean. Some grow upon rocks, and are found covering the interior of submarine caves. The Spongia parasitica is seen growing upon the back and legs of a species of crab; sometimes as many as forty individual sponges extend themselves over the crab, impeding the motion of its joints, spreading like a cloak over its back, or forming for its head grotesque and towering ornaments, from which the poor crab vainly attempts to disencumber itself.

Some species of the sponge grow to a very large size; one has been found in the East Indies in the form of a cup, capable of containing ten gallons of water. The fibrous part of the sponge is the skeleton of the animal; the large apertures (see fig. 158, b,) serve to carry out fluids from within; while the water by which the animal is nourished, is imbibed by minute pores: this continual circulation of water is one of the most important functions of the living sponge. These animals resemble plants in their manner of producing others; they form a species of germ, like the bud growing upon the stalk; this falls off from the stem, and becomes a perfect animal. If a part of one of these animals is separated from the rest, it will itself be as perfect a living animal as was the whole before. A polypus can be divided into as many animals as it contains atoms; some of this order are very properly called hydras, (many-headed.) Besides these, there is another order of animal substances, infusoria, which appear like a homogeneous mass, having no appearance of any limbs whatever; these are either angular, oval, or globular.

LECTURE XLVII.

COMPARISON BETWEEN ANIMALS AND PLANTS.

In our last lecture, after a glance upwards to the heavenly bodies, we returned to our globe, and considered its various substances; here we found two classes of bodies, inorganized and organized substances; the former including minerals, the latter embracing the animal and vegetable kingdoms. We then took a brief view of the animal creation.

At the head of the animal kingdom, we found man, sufficiently resembling brute animals in his material frame to constitute part of an extensive class, embracing the ape, elephant, and dog; yet between the lowest degree of intelligence in the human race, and the highest faculties of brutes, there is a line of distinction marked by the hand of the Almighty, in characters too obvious for doubt. God said, "Let us make man in our own image, and he breathed into him the breath of life, and man became a living soul."

Some writers have attempted to show that man differs only from the inferior order of animals in possessing a greater variety of instincts. But however wonderful may appear the instinctive perception of brutes, they are destitute of reason, and incapable of being

Sponge-Manner in which these animals are reproduced-Recapitulation-Man at the head of the animal kingdom-How resembling inferior animals.

the subjects of moral government; we must, therefore, both from our own observation and the declarations of scripture, infer, that the faculties of man differ not in degree only, but distinctly in their nature, from those of all other beings upon our globe.

"Man, (says Buffon,) by his form and the perfection of his organs, and as the only being on earth endowed with reason, seems properly placed at the head of the kingdom of nature. All, in him, announces the lord of the earth; his form marks his superiority over all living beings; he stands erect, in the attitude of command; he can gaze upon the heavens; on his face is imprinted the character of dignity; the image of his soul is painted upon his features, and the excellence of his nature penetrates through his material organs, and animates the expression of his countenance."

In the orders of animals nearest to man, we find the senses of sight, touch, taste and smell, equally perfect as those possessed by him, and in some cases they are even more acute; but as we proceed downwards through the gradations of animal existence, we perceive the number and acuteness of the senses to diminish-we find some beings with but four senses, some with three, others with two, and lastly, in Zoophytes, we find only the sense of touch, and that so faintly exhibited as almost to lead us to doubt its existence. Let us now return to the distinction between animals and vegetables. You now perceive that although you would find no difficulty with regard to a nightingale and a rose, to discover to which of the king. doms of nature they belong; yet with respect to a sponge or coral, a mushroom or lichen, it would be somewhat difficult, without a previous knowledge of their classification, to say which is called animal, and which vegetable, or to give the distinctions between them. We have seen among the zoophites, that the polypus, like a vegetable, may be increased by cutting shoots and ingrafting them upon other animals.

With respect to sensation, some plants seem to possess this, apparently even in a greater degree than some of the last orders of animals; the sensitive plant shrinks from the touch; the Dionea suddenly closes its leaves upon the insect which touches them; the leaves of plants follow the direction of light, in order to present their upper surfaces to its influence; as you may observe in flower pots placed by a window. The seed of a plant, in whatever situation it may be placed in the earth, always sends its root downwards, and its stem upwards; in these cases, does there not seem as much appearance of sensation and instinct, and even more, than in the lower orders of animals?

We find, then, that the possession, or want of instinct, does not constitute a mark of distinction between animals and plants.

Some have attempted to draw a line of distinction, by considering that locomotion, or the power of changing place, belongs to animals only; but this criterion seems to fail, since we find animals fixed to the bottom of the sea, or growing upon rocks, and plants moving upon the surface of the water.

Another mark of distinction has been given, in the supposed presence of nitrogen in animals, detected by a peculiar odour when animal substances are burning, similar to what we perceive in the combustion of bones; but nitrogen having been discovered in some vegetables, this proof is no longer considered infallible.

It appears then, from a comparison between animals and vegetables, that these beings are closely connected by the essential charac

How differing from them.

ters of organization; that it seems impossible to distinguish them by any trait that belongs exclusively to either; that the connexion between them appears the most striking in the least perfect species of both kingdoms; and that as we recede from this point, the differences become more numerous and more marked.

We may illustrate this view, by imagining two ascending chains, rising from one common point, each side of the chain becoming more and more unlike in proportion to the intervening distance from the centre. From this same central point, also proceeds the chain of inorganized substances; some imperfect animals resembling plants in their outward form, some, both of animals and plants, resembling minerals in their hard and calcareous coverings and shapeless forms.

Having thus learned the almost imperceptible gradations by which the animal and vegetable kingdoms are blended, we must, in stating the important differences which exist between animals and plants, consider the imperfect species of both kinds as exceptions to any general rule, and confine ourselves to perfect animals and plants.

1st. Plants differ from animals with respect to the elements which compose them; carbon, hydrogen, and oxygen, form the base of vegetable substances; animals exhibit the same elements, with this important distinction, that carbon prevails in plants, and nitrogen in animal food.

2d. They differ in their food; plants are nourished with inorganized matter, absorbed with water, which holds in solution various substances; animals are mostly nourished either by vegetable or other animals.

3d. Plants throw off oxygen gas, and inhale carbonic acid; animals, in respiration, inhale oxygen gas and throw off carbonic acid. 4th. Although plants and animals both possess a principle of life, it is in the one case much more limited than in the other; exhibiting itself in plants by a feeble power of contraction or irritability; in animals appearing in sensation, muscular movement, and voluntary motion.

We see, then, many important differences between perfect animals and perfect plants. We have, in numerous instances, pointed out striking analogies between the two great divisions of organized bodies: this subject might be greatly enlarged; but we have already, amid the multitude of interesting facts and reflections presented by the vegetable creation, far exceeded the bounds originally prescribed. A few remarks on the inorganic matter upon and around the earth, and our course of Lectures is closed.

Inorganic bodies form the solid base of the globe. Minerals are spread upon the face of the earth, or lie buried beneath its surface. They form vast masses of rocks, chains of mountains, and the ground upon which we tread. The Water occupies a still greater surface of the earth than the land; it is filled with life and animation; the treasures and wonders of the deep seem almost unbounded. The Air, lighter than earth and water, extending on all sides about forty miles in height, surrounds the whole globe, separating us from the unknown elements which exist beyond it. Heat, or Caloric, is a subtle fluid which pervades all matter, in an increasing proportion from solids to fluids, and fluids to gases. Light, reflecting its hues from terrestrial objects, produces, by the decomposition of its rays all the beautiful variety of colouring.

Result of the comparison between animals and vegetables-Chains of beings proceeding from one point-Differences between animals and plants-Different kinds of inorganic matter-The Deity manifested in his works.

Wherever we turn our eyes, we behold wonders; "if we go up to heaven, God is there;" "the firmament showeth forth his handywork;" if we contemplate the earth on which we are placed, with its varied tribes of beings, and the provision made for their comfort and subsistence, we realize, that it is indeed GOD, "who maketh the grass to grow on the mountains, and herbs for the use of man."

The universe, how vast! exceeding far

The bounds of human thought; millions of suns,
With their attendant worlds moving around
Some common centre, gravitation strange e!
Beyond the power of finite minds to scan!
Can HE, who in the highest heav'n sublime,
Enthron'd in glory, guides these mighty orbs—
Can He behold this little spot of earth,
Lost midst the grandeur of the heav'nly host:
Can GOD bestow one thought on fall'n man?

Turn, child of ignorance and narrow views,
Thy wilder'd sight from off these dazzling scenes ;
Turn to thy earth, and trace the wonders there.
Who pencils, with variegated hues,

The lowly flower that decks the rippling stream,
Or gorgeously attires the lily race?

Who with attentive care, each year provides
A germ to renovate the fading plant

And gives soft show'rs and vivifying warmth.
Kindling within the embryo inert

The little spark of life, unseen by all,

Save him who gave it, and whose care preserved ?
Who teaches, when this principle of life,

Thus animated, swells the germ within,

And bursts its tomb, rising to light and air-
Who teaches root and stem to find their place,

Each one to seek its proper element?

Who gilds the insect's wings, and leads it forta
To feast on sweets and bask in sunny ray?

None can the life of plant or insect give,

Save God alone;-He rules and watches all;
Scorns not the least of all His works; much less
Man, made in his image, destin'd to exist

When e'en yon brilliant worlds shall cease to be.
Then how should man, rejoicing in his GOD
Delight in his perfections, shadow'd forth
In every little flow'r and blade of grass!
Each opening bud, and care-perfected seed,
Is as a page, where we may read of GOD.

PART V.

APPENDIX

TO THE

LECTURES ON BOTANY,

CONTAINING

I. ILLUSTRATIONS OF THE HABITS OF PLANTS,

(With Eight Engravings.)

II. NATURAL ORDERS..

III. DESCRIPTIONS OF GENERA.

IV. DESCRIPTIONS OF SPECIES.

V. VOCABULARY.

VI. SYMBOLICAL LANGUAGE OF FLOWERS.

VII. ALPHABETICAL INDEX.

VIII. COMMON NAMES OF PLANTS.