or permanent; the same variety is to be traced among vegetables. Unquestionably the greater number of animals are of the migratory kind, yet 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 regarded as locomotive or migratory. The natural order SENTICOSE, the ICOSANDRIA 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,† 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 amphibious, 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-newt has been occasionally found imbedded in large masses of ice, perfectly torpid and apparently frozen; and that the common eel, when equally frozen and torpified, is capable of being conveyed a thousand miles up the country, as from St. Petersburg, 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 * Orchis morio, or latifolia. Lacerta aquatica. † Scabiosa succisa, or devil's bit. 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 themometer 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. Animals are capable of enduring a heat quite as extreme. Air has often been breathed by the human species with impunity at 264°. Tillet mentions 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.t 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 7740: Sonnerat, however, found fishes existing in a hot spring at the Manillas at 158° Fahr. ; 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 phænomena perfectly consonant in their nature, and altogether as extraordinary, if 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 form 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 * 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 Reaumur's thermometer, and calculates the heat upon this at 690, 96 already observed that some of them, and especially among the algae and the mosses, are nearly altogether incombustible, as the byssus asbestos, which, on being thrown into the fire, instead of burning, is converted into glass; and the fontinalis 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 sub-aqueous 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 element; the vegetable world is not without instances of a similar power. The algae, 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 flourish entirely covered with water, or with their roots alone shooting into a moist soil. Animals of various kinds are aërial; perhaps the term is not used with strict correctness. It will, at least, apply with more correctness to plants. All the most succulent plants of hot climates are of this description: such are several of the palms and of the canes; and the greater number of plants that embellish the arid Karro fields of the Cape of Good Hope.* Succulent as they are, these will only grow in soils or sands so sere and adust that no moisture can be extracted from them, and are even destroyed by a full supply of wet or by a rainy season. The Solandra grandiflora, a Jamaica shrub, was long propagated in our own stoves by cuttings, which, though freely watered, could never be made to produce any signs of fructification, notwithstanding that the cuttings grew several feet in length every By accident a pot with young cuttings was mislaid and forgotten in the Kew garden, and had no water given it; it was hereby reduced to its healthy aridity, and every extremity produced a flower.† season. And hence it is an opinion common to many of the ablest physiologists of the present day, that these derive the whole of their nutriment from the surrounding atmosphere; and that the only advantage which they acquire from thrusting their roots into such strata is that of obtaining an erect position. There are some quadrupeds that appear to derive nutriment in the same manner. Thus the bradypus tridactylus, or sloth, never drinks, imbibes by its cutaneous absorbents, and trembles at the feeling of rain; and, in common with the bird tribes, has only one ultimate or excrementary duct; while the olive cavyt avoids water of every kind almost as pertina*The only rain that waters this tract is that which falls for a few weeks in the winter; during the hot and fertile months there is no rain whatever. † Smith's Introduction to Botany, &c. p. 141. Cavia Acuschy. This is the more extraordinary, because the c. Cobaya, or Guineapig, drinks freely; and the c. Capybara, or river cavy, is fond of swimming and diving. ciously, as does also the ostrich, which is in consequence said by the Arabs never to drink. And yet these are animals almost as succulent as any we are acquainted with. But however true this may be with regard to animals, we have manifest proofs that vegetables of certain tribes and descriptions are altogether supported by the atmosphere that surrounds them; for, important as is the of a root to plants in general, there are several which have no root organ whatever, and can derive nutriment in no other way. The water-caltrop* is an instance directly in point. The seed of this plant has no rostel, and consequently can never, in the first instance, become rooted. From the horned nut or pericarp of the seed, as it lies in water, which is its natural element, shoots forth a long plumule perpendicularly towards the surface of the stream; during the ascent of which a variety of capillary branched leaves shoot forth from the sides of the plumule, some of which bend downward, and fix the whole plant to the bottom by penetrating into the soil below the stream; the leaves alone in this late stage of germination acting the part of a root, and giving maturity to the still unfinished plant. The cactus genus, in some of its very numerous species, offers us an example of similar evolution; and especially in the opuntia tribe, or that which embraces the prickly pears or Indian figs of our green-houses, of which the cochineal plant is one form. Of these, several grow by the mere introduction of one of their thick fleshy leaves into a soil of almost any kind that is sufficiently dry; they obtain an erect position, but never root, or shoot forth radicles: and hence almost the whole of their moisture must necessarily be derived from the surrounding atmosphere. Perhaps one half of the fuci have no root whatever many of them, indeed, consist of vesicles or vesicular bulbs alone, sessile upon the matrix of some stone or shell that supports them, and propagate their kinds by offsets, without any other vegetable organs. The seeds of the fucus prolifer sometimes evolve nothing but a leaf; the plant being propagated also by leaf upon leaf, either forked or elliptic, without root. The aphyteia hydnora is a curious instance in point. This plant is equally destitute of leaves, stem, and root; and consists alone of a sessile, coriaceous, and succulent flower, eaten as a luxury by the Hottentots, and parasitic to the roots of the euphorbia Mauritanica; flower propagating flower from generation to generation. But perhaps the plant most decisive upon this subject is the aërial epidendrum, first, if I mistake not, described by that excellent Portuguese phytologist Loureiro, and denominated aërial from its very extraordinary properties. This is a native of Java and the East Indies beyond the Ganges; and, in the latter region, it is no uncommon thing for the inhabitants to pluck it up, on account of the elegance of its leaves, the beauty of its flower, and the exquisite odour it diffuses, and to suspend it by a silken cord from the ceilings of their rooms; where, from year to year, it continues to put forth new leaves, new blossoms, and new fragrance, excited alone to new life and action by the stimulus of the surrounding atmosphere. That stimulus is oxygene; ammonia is a good stimulus, but oxygene possesses far superior powers, and hence without some portion of oxygene few plants can never be made to germinate. Hence, too, the use of cowdung and other animal recrements, which consist of muriatic acid and am *Trapa natans. † Cactus coccinellifer. Epidendrum flos aeris, monia: while in fat, oil, and other fluids, that contain little or no oxygene, and consist altogether, or nearly so, of hydrogene and carbone, seeds may be confined for ages without exhibiting any germination whatever. And hence, again, and the fact deserves to be extensively known, however torpid a seed may be, and destitute of all power to vegetate in any other substance if steeped in a diluted solution of oxygenated muriatic acid, at a temperature of about 46° or 48° of Fahrenheit, provided it still possess its principle of vitality it will germinate in a few hours. And if, after this, it be planted, as it ought to be, in its appropriate soil, it will grow with as much speed and vigour as if it had evinced no torpitude whatever. I have said that few plants can be made to germinate when the oxygene is small in quantity, and the hydrogene abundant and I have made the limitation, because aquatic plants, and such as grow in marshes, and other moist places, are remarkable, not only for parting with a large quantity of oxygene gas, but also for absorbing hydrogene gas freely; and are hence peculiarly calculated for purifying the regions in which they flourish, and in some sort for correcting the mischief that flows from the decomposition of the dead vegetable and animal materials that is perpetually taking place in such situations, and loading the atmosphere with febrile and other miasms. But the instances of resemblance between animal and vegetable physiology are innumerable. Some plants, like a few of our birds, more of our insects, and almost all our forest beasts, appear to sleep through the day, and to awake and become active at night; while the greater number, like the greater number of animals, resign themselves to sleep at sunset, and awake re-invigorated with the dawn. Like animals, they all feel the living power excited by small degrees of electricity, but destroyed by severe shocks; and like animals, too, they differ in a very extraordinary degree in the duration of many of their species. Some tribes of boletus unfold themselves in a few hours, like the ephemera and hemerobius tribes (May-fly and Spring-fly), and as speedily decay. Several of the fungi live only a few days; others weeks or months. Annual plants, like the greater part of our insects, live three, four, or even eight months. Biennial plants, like the longer-lived insects, and most of our shell-fishes, continue alive sixteen, eighteen, or even twenty-four months. Many of the herbaceous plants continue only a few years, but more for a longer period, and imitate all the variety to be met with in the greater number of birds, quadrupeds, and fishes; while shrubs and trees are, for the most part, coequal with the age of man, and a few of them equal that allotted to him in the earliest periods of the world. Of these last, the Adansonia digitata, or calabash tree, is perhaps one of the most extraordinary. Indigenous to the land of the patriarchs, and still outrivalling the patriarchal age, this stupendous tree, compared with which our own giant oak, in bulk as well as in years, is but an infant, seems to require not less than a thousand years to give it full vigour and maturity. Extending its enormous arms over the dry and barren soil from which it shoots naturally, it affords shelter to whole nations of barbarians, and on its pleasant subacid fruit administers an ample supply to their hunger. Let it not, however, be imagined that, by pointing out such frequent instances of resemblance between animal and vegetable life, I mean to degrade the rank of animal being from its proper level; for it will be one of the chief objects of our subsequent studies to develope and delineate its multiform and characteristic superiorities. I am only tracing at present |