Those grains which are considered as the seeds of mush rooms, are by some supposed to be merely buds or germs. This opinion, which was first proposed by Gaertner, and since that time maintained by many able botanists, is consi dered as supported by the analogy of the zoophytes. To us this seems to be a mere dispute about words. It is unwarrantable to expect a close resemblance between the seeds of mushrooms and the seeds of stameniferous plants, when they differ so widely in their general form. The seeds of the former may, for aught we know, resemble the parent plant in miniature ; and by the simple enlargement of their parts, without the production of any new organs, arrive at But experiments are still wanting to determine this point.
If the examination of the mode of growth of the fungi he involved in such obscurity, in what condition may we expect to find their systematic classification ? In the system of Linnaeus, they constitute the last order of the class Cryp togarnia ; and were distributed by him into the following genera : Agaricus, Boletus, Ilydnum, Phallus, Clathrus, Helvetia, Peziza, Clavaria, Lycoperdon, and Mucor. Since his days, the species have been investigated with great care, and many curious facts in their history have been ascer tained; yet still they have not obtained from botanists that attention to which they seem entitled, on account of the curious forms which they exhibit, the substances which enter into their COM position, and the economical uses to which they have been applied. In this department of botany, no one is deserving of higher praise than 1\1. Bulliard. This author has contributed, more perhaps than any other, to the illus tration of this intricate tribe, in his work entitled, Chan:1dg ?ions de la France. This work, besides containing accurate descriptions of the different fungi of France, exhibits at the same time faithful delineations of their form. In the same rank we must place the British Fungi of Al r Sowerby, the most splendid botanical publication which has appeared, in reference to our native plants. But here we must observe, that although the figures are admirable, the accompanying descriptions are extremely imperfect. This deficiency, however, we trust will soon be amply supplied by the learn ed President of the Linnwan Society, in the fourth volume of that classical work, the Flora Britannica, which for the space of ten years has been anxiously wished for by the British botanist. But it is to Persoon that the world is in debted for the most judicious and systematic arrangement of the Fungi. It was necessary to take a comprehensive view of this tribe of plants as a whole, to overlook the old genera, and to form anew the various species into natural groups or genera, characterised by permanent differences in habit, form, and structure. This task Persoon has in a great measure accomplished, and has published the result of his labours, in two works entitled, Tentamen Dispositionis Methodicx Fungorum, and Obse:vationes Mycologicer.
In the Natural Method of Jussieu, the fungi form one of the orders of the acotyledonous division of plants. They do not admit of generic arrangement according to the parts of fructification, so conveniently as the phenogamous plants, yet still the position of the seed-vessel furnishes the means of the more general classification ; while their form, colour, and consistence, aid us in the discrimination of the species.
By Persoon they are divided into two great tribes, according as the capsule is situated on the outside or in the interior of the plant.
The GymNocARPi have their capsules or seed-vessels situated on the external surface. In form as well as in structure, the plants of this tribe present very remarkable diffeiences, and even the parts destined for the production of the seed, exhibit very various appearances. These dif ferences, however, are not without their use, as they enable us to combine the various genera under different families, and thus assist the student, by diminishing the labour of investigation. This tribe is accordingly divided into five families, and contains twenty-one genera.
The ANGIOCARPI have the capsule placed internally ; and in some it is contained in a receptacle which is closed on all sides, at least in the young stages of the plant. To this receptacle Persoon has given the name of peridium. This tribe is divided into four families, and includes twen ty-five genera.
We now propose to consider more minutely these various genera, and to explain the characters upon which their ex istence depends. That their number will surprise the ',human student accustomed to refer to Hudson, Wither ing, and Lightfoot, we arc prepared to expect ; but we re quest his attention to the following circumstances. Accu rate observers of nature are become numerous ; botanists are now in possession of more powerful instruments, and better methods of analysis ; and their studies are greatly facilitated by accurate representations. Hence it is that new species are daily brought to light ; the history of old species elucidated ; and new genera formed by almost every observer, in consequence of the discovery of new relations. The formation of new genera, is the necessary consequence of the enlargement of the science. Linnaeus was not ac quainted with an hundred species of fungi; now their num ber has increased more than ten-fold. To us therefore the Linnxan genera have become useless. They mark the former state of the science, and they have contributed their share to the advancement of the study ; our systems and our genera must, in like manner, yield to the more extensive and accurate information of future observers. While we approve of the formation of new genera, therefore, where the state of the subject. demands it, we condemn that zeal so conspicuously displayed by some, in the frittering down of the old genera into as many new ones almost as there are species. Such naturalists mistake the object and the end of these subdivisions, imprudently attempt to pass beyond the bounds which limit the present state of the science, and endeavour to anticipate those changes which other disco veries and more enlarged views will render necessary. In this account of the genera, we have confined ourselves to those which are sanctioned by high authority. These are principally derived from the works of French naturalists, who, unrestrained by the fastidious reserve of the British character, and possessed of more ample means through .national munificenee, have of late contributed materially to the enlargement of systematic botany and zoology. The description of one species at least will be subjoined to each genus, together with a reference to those works where faithful representations of them may be found.