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ceived seeds in the Fungus perosus crassus magnus of John Bauhin the little round bodies that are found in the peziza 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 similiarity 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 sub stance has changed its nature, form, and function, we must conclude that it is the degeneration of that part which producer 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 natrition are multiplied; but, as the las in the class ects belongs to the animal kingdom, fung ought, otwitas.anding 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 produc tions; 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

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FIG. 6.-Development of Eurotiam repens (after De Bary). A, small portion o mycelium with conidiophore c, and young ascogonium as. B. the spiral asco gonium (as), with the antheridium (p). D, the same, beginning to be sur rounded by the hyphæ forming the perithecium wall. D, the perithecium. E,F, sections of young perithecia: w, parietal cells; pseudo-parenchyma; as ascogonium. G, an ascus. H, an ascospore...

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-Cystopus candidus. A. a, conidia; b, conidiophores; c, conidium emitting zoospores; d, free zoospore. Bog, oogonium; os, oosphere; an, antheridium. C. Formation of zoospores by oospores. z, free zoospores. (After De Bary.) (x 400.)

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