CURIOSITIES RESPECTING VEGETABLES.—(Concluded.)

Fungus, or Mushroom.

By fungus, we mean the mushroom tribe. The ancients called them the children of the earth, to indicate the obscurity of their origin. The moderns have likewise been at a loss in what rank to place them; some referring them to the animal, some to the vegetable, and others to the mineral kingdom. Messrs. Wilck and Minchausen, have not scrupled to rank these bodies among animal productions; because, when fragments of them or their seeds were macerated in water, these gentlemen perceived a quantity of animalcules discharged, which they supposed capable of being changed into the same substance. It was an ancient opinion, that beef could produce bees; but it was reserved for Messrs. Wilck and Minchausen, to suppose that bees could produce beef. The former asserts, that fungi consist of innumerable cavities, each inhabited by a polype; and he does not hesitate to ascribe the formation of them to their inhabitants, in the same way as it has been said that the coral, the lichen, and the mucor, were formed. Hedwig has lately shewn how ill-founded this opinion is with respect to the lichen; and M. Durande has demonstrated its falsity with regard to the corallines.

“Indeed, (says M. Bonnet, speaking of the animality of fungi,) nothing but the rage for paradox could induce any one to publish such a fable; and I regret that posterity will be able to reproach our times with it. Observation and experiment should enable us to overcome the prejudices of modern philosophy, now that those of the ancient have disappeared and are forgotten.” It cannot be denied, that the mushroom is one of the most perishable of all plants, and it is therefore the most favourable for the generation of insects. Considering the quickness of its growth, it must be furnished with the power of copious absorption; the extremity of its vessels must be more dilated than in other plants. Its root seems, in many cases, to be merely intended for its support; for some species grow upon stones, or moveable sand, from which it is impossible they can draw much nourishment. We must therefore suppose, that it is chiefly by the stalk that they absorb. These stalks grow in a moist and tainted air, in which float multitudes of eggs, so small, that the very insects they produce are with difficulty seen by the microscope. These eggs may be compared to the particles of the byssus, 100,000 of which, as M. Gleditsch says, are not equal to one-fourth of a grain.

May we not suppose that a quantity of such eggs are absorbed by the vessels of the fungus, and that they remain there without any change, till the plant begins to decay? Besides, the eggs may be only deposited on the surface of the plant, or they may exist in water, into which they are thrown for examination. Do not we see that such eggs, dispersed through the air, are hatched in vinegar, in paste, &c. and wherever they find a convenient nidus for their development? Can it be surprising, then, that the corruption of the mushroom should make the water capable of disclosing certain beings that are really foreign to both? It is not more easy to acquiesce in the opinions of those naturalists who place the fungi in the mineral kingdom, because they are found growing on porous stones, thence called lapides fungarii; which, however, must be covered with a little earth, and be watered with tepid water, in order to favour the growth. Such mushrooms are no more the produce of the stone, than the lichen is of the rock to which it adheres, or the moss, of the tree on which it is found.

We have only to observe the growth of mushrooms, to be convinced that this happens by development, and not by addition or combination of parts, as in minerals. The opinion of Boccone, who attributed them to an unctuous matter performing the function of seed, and acquiring extension by apposition of similar parts; and that of Morison, who conceived that they grew spontaneously out of the earth by a certain mixture of salt and sulphur, joined with oils from the dung of quadrupeds; have now no longer any adherents. Fungi are produced, they live, they grow by development; they are exposed to those vicissitudes natural to the different periods of life which characterize living substances; they perish and die; they extract, from the extremity of their vessels, the juices with which they are nourished; they elaborate and assimilate them to their own substance: they are, therefore, organized and living beings, and consequently belong to the vegetable kingdom.

But whether they are real plants, or only the production of plants, is still a matter in dispute with the ablest naturalists. Some ancient authors have pretended to discover the seed of mushrooms; but the opinion was never generally received. Petronius, when he is laughing at the ridiculous magnificence of his hero Trimalcio, relates, that he had written to the Indies for the seed of morelle. These productions were generally attributed to the superfluous humidity of rotten wood, or other putrid substances. The opinion took its rise from observing that they grew most copiously in rainy weather. Such was the opinion of Trajus, king of Bauhin, and even of Columna, who, talking of the peziza, says, that its substance was more solid and harder, because it did not originate from rotten wood, but from the pituita of the earth. It is not surprising, that, in times when the want of experiment and observation made people believe that insects could be generated by putrefaction, we should find the opinion general, that fungi owed their origin to the putrescence of bodies, or to a viscous humour analogous to putridity. Malpighi could not satisfy himself as to the existence of seeds, which other botanists have pretended to discover. He only says, that these plants must have them, or that they perpetuate themselves, and shoot by fragments. Micheli, among the moderns, appears to have employed himself most successfully on this subject. He imagined, that he not only saw the seeds, but even the stamina, as well as the little transparent bodies destined to favour the dissemination and fecundation of these seeds. Before this author, Lister thought he perceived seeds in the Fungus perosus crassus magnus of John Bauhin: the little round bodies that are found in the pezizÆ and belvellÆ, at that time, passed for seeds; which did not appear at all probable to Marsigli, considering that the eye, when assisted with the very best microscopes, could perceive nothing similar in much larger fungi. Indeed, these bodies may be the capsules or covers of the seeds, if they are not the seeds themselves. However this may be, Marsigli, observing that fungi were often without roots or branches, and that they wanted flowers and seeds, the means which nature employs for the production of perfect plants, thought himself warranted in doubting whether these beings could be ranked in the number of vegetables. The doubts of Marsigli prompted him to observe the formation of fungi. Their matrix he called situs: he imagined they grew in places where they met with an unctuous matter, composed of oil mixed with nitrous salt, which, by fermentation, produced heat and moisture, and insinuated itself between the fibres of wood; that is, he imagined them the production of a viscous and putrescent humour. Lancisi, in like manner, considered fungi as owing their existence to the putrefaction of vegetables, and supposed them a disease in the plants; but he imagined “that the fibres of the trees were necessary to their production,” as is the case in the formation of galls; and compared them to the warts and other excrescences of the human body. He added, that such fungous vegetable tumors must necessarily assume various forms and figures, from the fluids which distend the tubes and vessels relaxed by putrescence, from the ductility of the fibres and their direction, and from the action of the air. This opinion has been refuted by the celebrated naturalist M. de Jussieu, in the Memoirs of the Academy of Sciences for 1728. He maintains, that the fungi have a great analogy with the lichen, which is allowed to be a vegetable; that, like the lichen, they are divested of stalks, branches, and leaves; that, like it, they grow and are nourished upon the trunks of trees, on pieces of rotten wood, and on all sorts of putrid vegetables; that they resemble the lichen too in the rapidity of their growth, and the facility with which many of them may be dried, and restored to their former figure upon being immersed in water; and lastly, that there is a great similarity in the manner in which their seeds are produced. He affirms, that only the warts and excrescences which grow on animal bodies, and the knots and other tumors that are to be found on trees, can be compared with each other; for they are composed equally of the solid and liquid substance of the plant or animal on which they grow; whereas, the matter of the fungi is not only quite distinct from that of the plants on which they are found, but often entirely similar to the substance of those that spring immediately from the earth.

The organization (says M. de Jussieu) which distinguishes plants and other productions of nature, is visible in the fungi, and the particular organization of each species is constant at all times, and in all places; a circumstance which could not happen, if there were not an animal reproduction of species, and consequently a multiplication and propagation by seed. This is not, he says, an imaginary supposition, for the seeds may be felt like meal upon mushrooms with gills, especially when they begin to decay; they may be seen with a magnifying glass, in those that have gills with black margins: and, lastly, says he, botanists can have no doubt that fungi are a distinct class of plants; because, by comparing the observations made in different countries, with the figures and descriptions of such as have been engraved, the same genera and the same species are every where found.

Notwithstanding this refutation by M. de Jussieu, another naturalist, M. de Necker, has lately maintained, in his Mycitologia, That the fungi ought to be excluded from the three kingdoms of nature, and be considered as intermediate beings. He has observed, like Marsigli, the matrix of the fungi; and has substituted the word carchte (initium faciens) instead of situs; imagining that the rudiment of the fungus cannot exist beyond that point in which the development of the filaments of fibrous roots is perceived. He allows, that fungi are nourished and grow like vegetables; but he thinks that they differ very much from them in respect of their origin, structure, nutrition, and rapidity of growth. He says, that the various vessels which compose the organization of vegetables, are not to be found in the fungi, and that they seem entirely composed of cellular substance and bark; so that this simple organization is nothing more than an aggregation of vessels endowed with a common nature, that suck up the moisture in the manner of a sponge; with this difference, that the moisture is assimilated into a part of the fungus, and not merely imbibed for nutrition.

Lastly, That the fructification, the only essential part of a vegetable, and which distinguishes it from all other organized bodies, being wanting, fungi cannot be considered as plants. This, he thinks, is confirmed by the constant observation of those people who gather the morelle and the mushroom, and who never find them in the same spots where they had formerly grown. As the generation of fungi (says M. Necker) is always performed when the parenchymatous cellular substance has changed its nature, form, and function, we must conclude that it is the degeneration of that part which produces these bodies.But if fungi were owing merely to the degeneration of plants, they would be still better entitled to constitute a new kingdom. They would then be a decomposition, not a new formation, or new bodies. Besides, we cannot deny, that in those bodies which form the limit between the animal and vegetable kingdoms, the organization becomes simple, as the organs destined for nutrition are multiplied; but, as the last in the class of insects belongs to the animal kingdom, fungi ought, notwithstanding the simplicity of their organization, still to belong to the vegetable kingdom.

The parenchymatous, or cellular substance, which, as M. Bonnet says, is universally extended, embraces the whole fibrous system, and becomes the principal instrument of growth, must naturally be more abundant in those productions; and this accounts for the rapidity of their enlargement. Besides, growth, whether slow or rapid, never was employed to determine the presence or absence of the vegetable or animal character. The draba verma, which, in a few weeks, shoots, and puts forth its leaves, flowers, and fruit, is not less a plant than the palm. The insect that exists but for a day, is as much an animal, as the elephant that lives for centuries. As to the seeds of the fungi, it is probable that nature meant to withdraw from our eyes the dissemination of these plants, by making the seeds almost imperceptible; and it is likewise probable, that naturalists have seen nothing but their capsules. Since, however, from the imperfection of our senses, we are unable to perceive these seeds, because those bodies which have been called their seeds, and the fragments or cuttings of the plants themselves, have not produced others of the same species; Nature seems to have reserved for herself the care of disseminating certain plants: it is in vain, for instance, that the botanist sows the dust found in the capsules of the orchis, though every one allows it to be the seed.

But, after all, what are those parts in the fungi casually observed by naturalists, and which they have taken for the parts of fructification? These are quite distinct from the other parts; and whatever may be their use, they cannot have been formed by the prolongation of the cellular substance, or of the fibres of the tree on which the fungus grows: they are, therefore, owing, like flower and fruit, to the proper organization of the plant. The plants, however, have a particular existence, independent of their putrefying nidus. The gills of certain fungi, which differ essentially from the rest of the plant in their conformation, would be sufficient to authorize this latter opinion. But can putrefaction create an organic substance? Nature undoubtedly disseminates through the air, and over the surface of the earth, innumerable seeds of fungi, as well as eggs of insects. The plant and the animal are excluded, when the nidus, in which they are deposited, or the temperature, is favourable for their development. No fortuitous concourse, either of atoms or fluids, could produce bodies so exquisitely and so regularly organized. It is sufficient, to throw one’s eye on the beautiful plates which Schoeffer has published of them, and compare them, by the glass, with the warts and other excrescences of animals, to be convinced that they have not the same origin. The function of the cellular substance in vegetables must be greatly superior to that in animals, if it could produce any thing but deformities. The greater part of fungi exhibit a configuration much too regular, constant, and uniform, to be the effect of chance or putrefaction. As this form is preserved the same in all places where fungi have been found, it follows, that they contain in themselves the principles of reproduction. They resemble the misletoe, and other parasitic plants, which are perfectly distinct from the trees on which they grow. The fungi, therefore, are organized and living substances,—or true plants.