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will grow on no other soil, thrives here and fixes it, and prevents it from being washed back or blown away; to which the lime-grass, couchgrass, sand-reed, and various species of willow, lend their aid. Thus fresh lands are formed, fresh banks upraised, and the boisterous sea repelled by its own agency.
Frosts and suns, water and air, equally promote fructification in their respective ways; and the termes, or white ant, the mole, the hampster, and the earth-worm, break up the ground or delve into it, that it may enjoy their salubrious influences. In like manner, they are equally the ministers of putrefaction and decomposition; and liverworts and funguses, the ant and the beetle, the dew-worm, the ship-worm, and the woodpecker, contribute to the general effect, and soon reduce the trunks of the stoutest oaks, if lying waste and unemployed, to their elementary principles, so as to form a productive mould for successive progenies of animal or vegetable existence. Such is the simple but beautiful circle of nature. Every thing lives, flourishes, and decays: every thing dies, but nothing is lost; for the great principle of life only changes its form, and the destruction of one generation is the vivification of the next. Hence, the Hindu mythologists, with a force and elegance peculiarly striking, and which are no where to be paralleled in the theogonies of Greece and Rome, describe the Supreme Being, whom they denominate Brahm, as forming and regulating the universe through the agency of a triad of inferior gods, each of whom contributes equally to the general result, under the names of Brahma, Visnu, and Iswara; or the generating power, the preserving or consummating power, and the decomposing power. And hence the Christian philosopher, with a simplicity as much more sublime than the Hindu's, as it is more veracious, exclaims, on contemplating the regular confusion, the intricate barmony, of the scenes that rise before him
ON THE GENERAL ANALOGY OF VEGETABLE AND ANIMAL LIFE.
(The subject continued.)
THE perfection of an art consists in the employment of a comprehensive system of laws, commensurate to every purpose within its scope, but concealed from the eye of the spectator; and in the production of effects that seem to flow forth spontaneously, as though uncontrolled by their influence, and which are equally excellent, whether regarded individually, or in reference to the proposed result.
Such is the great art of nature: and he who would study it with success must, as far as he is able, trace out its various laws, and reduce them to general principles, and collect its separate phænomena, and digest them
+ Triticum repens.
† Arundo arenaria.
§ See upon this subject the Swedish Amœnitates Academica, vol. v. art. 80. by J. H. Hagen. 1757, entitled Ñatura Pelagi.
into general classes. This, in many instances, we are able to do; and, in such cases we obtain a tolerable insight into the nature of things. But so vast, so unbounded is the theatre before us, so complicated is its machinery, and so closely does one fact follow up and press upon another, that we are often bewildered and lost in the mighty maze, and are incapable of determining the laws by which it is regulated, or of arranging the phænomena of which it is composed.
The zoologist, in order to assist his inquiries, divides the whole animal creation into six general heads or classes; as those of mammals, birds, amphibials, fishes, insects, and worms. Each of these classes he subdivides into orders; of each of his orders he makes a distinct section for a multitude of kinds or genera; and each of his kinds becomes a still more subordinate section for the species or individuals of which the separate kinds consist. But he is perpetually finding, not only that many cases in each of his inferior divisions are so equally allied to other divisions that he knows not how to arrange them, but that even his classes or first divisions themselves labour under the same difficulty; since he occasionally meets with animals that by the peculiarity of their construction seem equally to defy all artificial method and all natural order. Thus the myxine glutinosa, which by Linnéus was regarded and ranked as a worm, has been introduced by Bloch into the class of fishes, and is now known by the name of gastrobranchus cæcus, or hag-fish. The siren lacertina, which was at first contemplated by Linnéus as an amphibious animal of a peculiar genus, was afterwards declared by Camper and Gmelin to be a fish, approaching the nature of an eel, and was arranged accordingly. It has since, however, been restored from the class of fishes to that of amphibials, and is in the present day believed by various zoologists to be nothing more than a variety of the lizard. And thus the hippopotamus, the tapir, and the swine, which by Linnéus were ranked in the fifth order of mammals with the horse, are arranged by Cuvier with the rhinoceros and the sokotyro, that have hitherto formed a part of the second order.
The eel, in its general habits and appearance, has a near similitude to the serpent; many of its species live out of the water as well as in it; and, like the serpent, hunt for worms, snails, and other food, over meadows and marshes.
The platypus anatinus, or duck bill, (the ornithorhyncus paradoxus of Blumenbach,) one of the many wonders of New South Wales, unites in its form and habits the three classes of birds, quadrupeds, and amphibials. Its feet, which are four, are those of a quadruped; but each of them is palmate or webbed, like a wild fowl's; and instead of lips it has the precise bill of a shoveler or other broad-billed water bird; while its body is covered with a fur exactly resembling an otter's. Yet it lives, like a lizard, chiefly in the water, digs and burrows under the banks of rivers, and feeds on aquatic plants and aquatic animals. The viverra or weasel, in several of its species, approaches the monkey and squirrel tribes; is playful, a good mimic, and possesses a prehensile tail. The flying squirrel, the flying lizard, or draco volans, and especially the bat, approach in their volant endowment the buoyancy of birds, and are able to fly by winged membranes instead of by feathers. The exocetus volitans, or flying-fish, and several other fishes, derive a similar power from their long pectoral fins; while the troctilus, or humming-bird, unites the class of birds with that of insects. It is in one of its species, t. minimus, the least of the feathered tribes; feeds, like insects, on the nectar of flowers alone, and like the bee,
or butterfly, collects it while on the wing, fluttering from flower to flower, and all the while humming its simple accent of pleasure. Its tongue, like that of many insects, is missile. When taken it expires instantly; and after death, on account of its diminutive size, the elegance of its shape, and the beauty of its plumage, it is worn by the Indian ladies as an ear-ring.
Such being the perplexity and seeming confusion that extend through the whole chain of animal life, it is not to be wondered at that we should at times meet with a similar embarrassment in distinguishing between animal life and plants, and between plants and minerals. I gave a cursory glance at this subject in our last lecture, and especially in regard to that extraordinary division of organized substances which, for want of a better term, we continue to denominate zoophytes; many of which, as, for example, various species of the alcyony and madrepore, bear a striking resemblance to crystals, and other mineral concretions; while great numbers of them, and particularly the corals, corallines, and some other species of alcyony, as the sea-fig, sea-quince, pudding-weed, and above all the stone-lily, (which last, however, is now only found in a petrified state,) have the nearest possible approach to a vegetable appearance. Whence, as I have already observed, among the earlier naturalists, who expressly directed their attention to these substances, some regarded them as minerals, and others as vegetables; and it is not till of late years, only, indeed, since it has been ascertained that the chemical elements they give forth on decomposition are of an animal nature, that they have been admitted into the animal kingdom.
Among plants, in like manner, we often meet with instances of individual species that are equally doubtful, not only as to what kind, order, or class of vegetable existence they belong, but even as to their being of a vegetable nature of any kind, till their growth, their habits, and their composition are minutely examined into. But independently of these individual cases, we also perceive, in the general principle of action in animal life, that the more it is investigated, the more it is calculated to excite our astonishment, and to indicate to us, so far as relates to the SUBORDINATE POWERS of the animal frame, the application of one common system to both, and to demonstrate one common derivation, from one common and Almighty Cause. Having, therefore, in our last lecture, submitted to your attention a brief outline of the structure of plants, I shall now proceed to point out a few of these general resemblances, and shall endeavour to select those which are either most curious or most prominent.*
Plants, then, like animals, are produced by ordinary generation; and though we meet with various instances of production by the generation of buds and bulbs, or of slips and offsets, the parallelism, instead of being hereby diminished, is only drawn the closer: for we meet with just as many instances of the same varieties of propagation among animals. Thus the hydra, or polype, as it is more generally called, the asterias, and several species of the leech, as the hirudo viridis, for example, are uniformly propagated by lateral sections, or pullulating slips or offsets; while almost every genus of zoophytic worms is only capable of increase by buds, bulbs,
*Consult also Mr. Knight's article, Phil. Trans. 1810, part ii. p. 179–181.
†Thus Aristotle, upon a subject which is generally supposed to be of modern discovery, Ωσπερ γαρ τα φυτα και ταυτα (scilicet) έντομα διαιρούμενα δυναται ζην. “ For, like plants, suck insects also maintain life, after slips or cuttings." Hist. Anim. lib. iv. ch. 8.
See a variety of other curious instances in the author's translation of Lucretius, note to b. ii. ver. 880.
or layers; and some of these animals, like the house-leek and various grasses, by spontaneous separation. In effect, most of the kinds now referred to, whether animals or vegetables, may be regarded less as single individuals than as assemblages or congeries of individuals; for in most of them every part exists distinctly of every other part, and is often a miniature of the general form. The various branches of a tree offer a similar example, and present a striking contrast with the various branches of a perfect animal. In the latter every distinct part contributes to one perfect whole: the arm of a man has no heart, no lungs, no stomach; but the branch of a tree has a complete system of organs to itself, and is hence capable in many cases of existing by itself, and producing buds, layers, and other kinds of offspring, when separated from the trunk. The dif ferent parts of the polype are equally independent, and are hence equally capable of a separate increase. It is owing to this principle we are able to graft and bud: and M. Trembley having applied the same kind of operation to the animals we are now speaking of, found that, by numerous grafts of different kinds upon each other, he was enabled to produce monsters as wild and extravagant as the most visionary poet or fabulist ever dreamed of.
The blood of plants, like that of animals, instead of being simple is compound, and consists of a great multitude of compacter corpuscles, globules for the most part, but not always globules, floating in a looser and almost diaphanous fluid. From this common current of vitality, plants, like animals, secrete a variety of substances of different, and frequently of opposite powers and qualities,-substances nutritive, medicinal, or destructive. And, as in animal life, so also in vegetable, it is often observed that the very same tribe, or even individual, that in some of its organs secretes a wholesome aliment, in other organs secretes a deadly poison. As the viper pours into the reservoir situated at the bottom of his hollow tusk a fluid fatal to other animals, while in the general substance of his body he offers us not only a healthful nutriment, but, in some sort, an antidote for the venom of his jaw: so the jatropha Manihot, or Indian cassava, secretes a juice or oil extremely poisonous in its root, while its leaves are regarded as a common esculent in the country, and are eaten like spinach-leaves among ourselves; though the root, when deprived, by exposure to heat, of this poisonous and volatile oil, is one of the most valuable foods in the world, and gives bread to the natives, and tapioca as an article of commerce. Its starch is like that of the finest wheat-flour, and combined with potatoes and sugar, yields a very excellent cider and perry, according to the proportions employed. In like manner, while the bark of the cinnamon tree (laurus Cinnamomum) is exquisitely fragrant, the smell of the flowers is highly offensive, and by most persons is compared to that of newly-sawn bones,-by St. Pierre to that of human excrement.* So the cascarilla bark and castor oil are obtained from plants poisonous in some part or other.
The amyris, in one of its species offers the balm-of-Gilead tree; in another, the gum-elemi tree; and in a third, the poison-ash, that secretes a liquid gum as black as ink. It is from a fourth species of this genus, I will just observe as I pass along, in order the more completely to familiarize
Mr. Marshall's account delivered to the Royal Society. See Thomson's Annals, Sept. 242.
it to us, that we obtain that beautiful plant which, under the name of rosewood, is now so great a favourite in our drawing-rooms.
The acacia nilotica,† or gum-Arabic tree, is a rich instance in proof of the same observation. Its root throws forth a fluid that smells as offensively as assafœtida; the juice of its stem is severely sour and astringent ; the secernents of its cutis exude a sweet, saccharine, nutritive gum, the common gum-Arabic of the shops, and its flowers diffuse a highly fragrant and regaling odour. So the Arenga palm produces sugar, an excellent sago, and a poisonous juice that even irritates the skin.
But perhaps the laurus, as a genus, offers us the most extensive variety of substances of different qualities. This elegant plant, in one of its species, gives us the cinnamon tree ;t in another, the cassia, or wild cinnamon ;§ in a third, the camphor tree;|| in a fourth, the alligator pear;¶ in a fifth, the sassafras ;** in a sixth, a sort of gum-Benjamin,ft though not the real gum-Benjamin, which is a styrax; while in a seventh, the 1. caustica, it exhibits a tree with a sap as poisonous as that of the manchineel.
And truly extraordinary is it, and highly worthy of notice, that various plants, or juices of plants, which are fatally poisonous to some animals, may not only be eaten with impunity by others, but will afford them a sound and wholesome nutriment. How numerous are the insect tribes that feed and fatten on all the species of euphorbia, or noxious spurge! The dhanesa, or Indian buceros, feeds to excess on the nux vomica; the landcrab‡‡ on the berries of the hippomane or manchineel-tree, and the loxia (grossbeak) of the Bahamas on the fruit of the amyris toxifera, or poisonash.§§ The leaves of the kalmia latifolia are feasted on by the deer and the round-horned elk, but are mortally poisonous to sheep, to horned cattle, to horses, and to man. The bee extracts honey without injury from its nectary, but the adventurer who partakes of that honey, after it is deposited in the hive-cells falls a victim to his repast.
There are some tribes of animals that exfoliate their cuticle annually, such as grasshoppers, spiders, several species of crabs, and serpents. Among vegetables we meet with a similar variation from the common rule, in the shrubby cinquefoil, indigenous to Yorkshire, and the plane-tree of the West-Indies, ¶¶ which most readers know sends forth every spring new colonies by means of runners, as we usually denominate them, in every direction, that shortly after they have obtained a settlement for themselves, break off all connexion with the parent stock.
Among animals, some are locomotive or migratory, and others stationary
† Mimosa nilotica, Linn.
*A. balsamifera. SL. Cassia. **L. Sassafras. $$ See on this subject the following curious papers in the Swedish Amoenitates Academics, vol. ii. art. 25 par Šueisens, by N. L. Hesselgren. The same subject continued by G. P. Tengmalon, Amen. Acad. vol. x. art. x. Usus Historia Naturalis, by M. Aphonin, art. 147. Id. in respect to birds, entitled Esca Avium domesticarum, by P. Holmbergen, p. 481.
It is also well worthy of remark, that various herbaceous plants which spring up among others that are esculent, yet are rejected by cattle when offered alone, give a higher relish and even salubrity to the fodder with which they are intermixed. This, as Sir J. E. Smith has admirably observed, is particularly the case with the grasses. "As man cannot live on tasteless unmixed flour alone, so neither can cattle in general be supported by mere grass, without the addition of various plants, in themselves too acid, bitter, salt, or narcotic, to be eaten unmixed. Spices, and a portion of animal food supply us with the requisite stimulus or additional nutriment, as the ranunculus tribes, and many others, season the pasturage and fodder of cattle."-Engl. Flora, vol. i.
¶¶ Platanus occidentalis.