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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 Linnæus were ranked in the fisth order of mammals with the horse, are arranged by Cuvier with the rhino. ceros 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 seet, 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 sur 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. miniinus, 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. Ils 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, seaquince, 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 ear. lier 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 manuer, we often meet with instances of individual species that are equally doubtful, not only as 10 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 and 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;t while almost every genus of zoophytic worms is only capable of increase by buds, bulbs, or layers; and some of these animals, like the houseleek 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 different parts of the polype are equally independent, and are hence equally capable of a separate increase. It is owing to this principle that we are able to grast and bud: and M. Trembly, having applied the same kind of operation to the animals we are now speaking of, found that, by numerous grasts 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 healthsul nutriment, but, in some sort, an antidote for the venom of his jaws : 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 wheatflour, 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 cinnainoniuin) 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

• 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, "120 ep ydp ru φυτά και ταύτα (scilicet) έντομα διαιρούμενα δύναται ζήν “ For, like plants, such insects also maintain liro after slips or cuttings."--Hist. Anim. lib. 8. See a variety of other curious instances in the author's translation of Lucretius, note to b. ii. ver. 880.

Mr. Marshall's account delivered to the Royal Society. See Thomson's Annals, Sept. p. 242.

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 it to us, that we obtain that beautiful plant which, under the name of rose-wood,t 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 asafætida; the juice of its stem is severely sour and astringent; the se cernments 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 ;9 in another, the cassia, or wild cinnamon ;ll in a third, the camphor tree ;P in a fourth, the alligator-pear;** in a fifth, the sassafras ;tt in a sixth, a sort of gum-benjamin, If though not the real gumbenjamin, which is a 'styrax ; while in a seventh, the L. 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 land-crabod on the berries of the hippomane or manchineel-tree, and the loxia (grossbeak) of the Bahamas on the fruit of the amyris toxifera, or poison-ash.||| 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, PP 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 or permanent; the same variety is to be traced among vegetables. Unquestionably the greater number of animals are of the migratory kind, yet

* A. torifera.
† A. balsamifera.

Mimosa nilotica, Linn.
0 L. cinnamomium.
! L. cassia.

L. camphora. ** L. persea. 11 L. sassafras.

11 L. benzoin. Og Cancer ruricola. III See on this subject the following curious papers in the Swedish Amenitates Academicæ, vol. ij. art. 25, par Sueisens, 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. Ib. in respect to birds, entitled Esca Avium domesticarum, by P. Holmbergen, p. 481, art. 163.

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 uninixed 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 aninal food supply us with the requisite stimulus or additional nutriment, as the ranunculus tribes, and many others, season the pasturage and fodder of cat lle.--Engl. Flora, vol. 1. T1 Potentilla fruticosa.

*** Platanus occidentalis.

in every order of worms we meet with some instances that naturally appertain
to the latter, while almost every genus and species of the zoophytic order,
its millepores, madrepores, tubipores, gorgonias, isises, corallines, and
sponges, can only be included under it. Plants, on the contrary, are for the
most part stationary, yet there are many that are fairly entitled to be re-
garded as locomotive or migratory. The natural order sentICOSÆ, the icosan-
DRIA POLYGYNIA of the sexual system, offers us a variety of instances of which
the fragaria or strawberry genus may be selected as a familiar example.
The palmate, the testicular, and the premorse rooted tribes afford us similar
proofs :-many of these grow from a new bulb, or knob, or radicle, while the
old root, of whatever description it may be, dies away; in consequence of
which we can only conclude that the vital principle of the plant has quitted
an old, dilapidated, and ruinous mansion, to take possession of a new one.
Insomuch that were a person, on the point of travelling to the East Indies, to
plant the root of an orchis,* or a scabious,f in a particular spot in his garden,
and to search for it in the same spot on his return home, he would be in no
small degree disappointed; and if he were to remain abroad long, he must
carry his pursuit to half an acre's distance, for thus far would some of these
roots perhaps have travelled in a few years.
· The male valisneria sails from shore to shore over the water in pursuit of
his female. And a multitude of sea-plants float through the ocean, and having
plenty of food wherever they go, send out no roots in order to search for it.

Plants, like animals, have a wonderful power of maintaining their proper temperature, whatever be the temperature of the atmosphere that surrounds them; and hence occasionally of raising the thermometer, and occasionally of depressing it. Like animals, too, they are found to exist in most astonishing degrees of heat and cold, and to accommodate themselves accordingly. Wherever the interest or curiosity of man has led him into climates of the highest northern latitudes; wherever he has been able to exist himself, or to trace a vestige of animal being around him; there, too, has he beheld plants of an exquisite beauty and perfection : perfuming, in many instances, the dead and silent atmosphere with their fragrances, and embellishing the barren scenery with their corols.

It is said that animals of a certain character, the cold blooded and amphi. bious, have a stronger tenacity to life than vegetables of any kind. But the assertion seems to have been hazarded too precipitately; for admitting that the common water-newtf has been occasionally found imbedded in large masses of ice, perfectly torpid and apparently frozen; and that the common eel,9 when equally frozen and torpified, is capable of being conveyed a thousand miles up the country, as from St. Petersburgh, for example, to Moscow, in which country, we are told, it is a common practice thus to convey it; and that both, on being carefully thawed, may be restored to as full a possession of health and activity as ever; yet the torpitude hereby induced can only be compared to that of deciduous plants in the winter months; during which season we all know that, if proper care be exercised, they may be removed to any distance whatever without the smallest inconvenience.

Plants, again, are capable of existing in very high degrees of heat. M. Sonnerat found the vitex agnus castus, and two species of aspalathus, on the banks of a thermal rivulet in the island of Lucon, the heat of which raised the thermometer to 174° of Fahrenheit and so near the water, that its roots swept into it. Around the borders of a volcano in the isle of Tanna, where the thermometer stood at 210°, Mr. Forster found a variety of flowers flourishing in the highest state of perfection; and confervas, and other water. plants, are by no means unfrequently traced in the boiling springs of Italy, raising the thermometer to 212° or the boiling point.

Aniinals are capable of enduring a heat quite as extreme. Air has often been breathed by the human species with impunity at 264o. Tillet mentions

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its having been respired at 300°; the Royal Academy asserts at 307°, or 130° Reaumur, in an oven, for the space of ten minutes ;* and Morantin gives a case at 325° Fahr., and that for a space of five minutes. Even in the denser medium of water, animals of various kinds, and especially fishes, have been occasionally traced alive and in health in very high temperatures. Thus Dr. Clarke asserts, that in one of the tepid springs of Bonarbashy, situated near the Scamander, or Mender, as it is now called, notwithstanding the thermometer was raised to 62° Fahr., fishes were seen sporting in the reservoir.

So in the thermal springs of Bahia in Brazil many small fishes are seen swimming in a rivulet that raises the thermometer to 88°, the temperature of the air being only 771°. Sonnerat, however, found fishes existing in a hot spring at the Manillas at 158° Fahr. :I and M. Humboldt and M. Bonpland, in travelling through the province of Quito in South America, perceived other fishes thrown up alive, and apparently in health, from the bottom of a volcano, in the course of its explosions, along with water and heated vapour that raised the thermometer to 210°, being only two degrees short of the boiling point.

In reality, without wandering from our own country, we may at times meet with a variety of other phenomena perfectly consonant in their nature, and altogether as extraordinary, is we only attend to them as they rise before us. Thus the eggs of the musca vomitoria, our common flesh-fly, or blow-fly, are often deposited in the heat of summer upon putrescent meat, and broiled with such meat over a gridiron in the forın of steaks, in a heat not merely of 212°, but of three or four times 212° ; and yet, instead of being hereby destroyed, we sometimes find them quickened by this very exposure into their larve or grub state. And although I am ready to allow that, in the simple form of seeds or eggs, plants or animals may be expected to sustain a far higher degree of heat or cold with impunity, than in their subsequent and more perfect state, yet it cannot appear more extraordinary that in such perfect state they should be able to resist a heat of 210° or 212°, than that in the state of seeds or eggs they should be able to exist in, and to derive benefit from, a heat three or four times as excessive.

In the vegetable world we meet with other peculiarities quite as singular, and which gives them an approach to the mineral kingdom: we have already observed that some of them, and especially among the algæ and the mosses, are nearly or altogether incombustible, as the byssus asbestos, which, on being thrown into the fire, instead of burning, is converted into glass; and the fon. tinalis antipyretica, a plant indigenous to the Highlands, but more frequent in Scandinavia, where from its difficulty of combustion it is used by the poor as a lining for their chimneys, to prevent them from catching fire.

Animals are often contemplated under the three divisions of terrestrial, aquatic, and aërial. Plants may be contemplated in the same manner. Among animals it is probable that the largest number consists of the first division; yet from the great variety of submarine genera that are known, and from nearly an equal variety, perhaps, that are not known, this is uncertain. Among vegetables, however, it is highly probable that the largest number belongs to the submarine section, if we may judge from the almost countless species of fuci and other equally prolific tribes of an aqueous and subaqueous origin, and the incalculable individuals that appertain to each species; and more especially if we take into consideration the greater equality of temperature which must necessarily exist in the submarine hills and valleys.

Many animals are amphibious, or capable of preserving life in either ele. ment; the vegetable world is not without instances of a similar power. The algæ, and especially in the ulva and fucus tribes, offer us a multitude of examples. The juncus, or rush, in many of its species, is an amphibious plant; so, too, is the oryza or rice-plant. In other words, all these will

Hist. de l'Acad. Royale des Sciences, 1764, p. 186, h. 16.
Travels, part II. Greece, Egypt, and the Holy Land, p. 111, 4to. ed.
He graduates by Rcaumur's thermometer, and calculates the heat upon this at 690.
Recueil d'Observations de Zoologie et d'anatomie comparée.

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