In addition, however, to the mere drying, certain notes and particulars are required, without which the best dried specimens are worthless; and, again, for the larger fungi to be of real service, the spores of each species must be separately preserved. As regards the drying of the fleshy fungi themselves, the process to observe is as follows:—Lay all ordinary Agarics out separately in a dry place, or in a current of dry air from six to twelve, or even twenty-four hours, according to the species, so that they may part with their superfluous moisture, and thus facilitate drying. In the case of species with glutinous pilei, it will be found that the gluten will more or less set, if carefully attended to, in a dry warm place. If the larger fleshy fungi are inadvertently placed under a propagating-glass, or left on a lawn or grassy place, or kept in damp air from over-night till next morning, the chances are that they will never properly dry at all. When the superfluous moisture has evaporated they may be put gently between drying-papers, but the weight put upon them must at first be of the slightest kind; ordinary books, more or less light, will be found quite sufficient; and few, or perhaps no other plants, require such frequent changing as Agarics. An hour, or often less, suffices for the first pressure, when care must be taken to supply them with fresh and perfectly dry paper, or they will immediately mould. It is a good plan, when the plants are half dry, to take them out of the papers and put them in dry air, or in a sunny place for a short time (the length of time being determined by experience and the nature of the species), to part with more of their moisture: so, with constant attention and frequent changing of the papers, very presentable specimens may at last be obtained. These dried fungi will now be found very useful for showing the more superficial characters of the plants; but without sections, spores, and proper notes, they will be next to useless. In Agarics it is of the first importance to show the nature of the attachment of the gills to the stem: and should the stems be furnished with a volva or annulus, this must be preserved with the greatest care—young specimens, too, in different stages of growth, are often of great value. If possible, it is well to have a series of dried specimens of each species; one, as in [Fig. 38], A, to display the nature of the tubes in Boletus and the gills in the Agaricini, whether they are thick or thin, crowded together or distant from each other, plain or serrated, free or annexed; another, as at B, to show the pileus, whether smooth or floccose, plain, warted, or zoned, and the nature of the margin, whether striate, bullate, or plain; a third, as at C, to show the attachment of pileus to stem in infancy; and, fourthly, a section or thin slice removed from the exact middle of the young plant from top to bottom, as at D: this will show the nature of the veil (if present), and whether universal or not; and if absent, whether the margin is at first straight, incurved, or involute. A similar section through the mature plant is also required, E and F ([Fig. 39]): this will give the attachment of gills to stems (a character of great importance), and the nature of the stem itself, whether solid, stuffed, or hollow. Great care and experience are required to cut a thin and perfect slice from the middle of a tender Agaric or Boletus; for there is often a sort of articulation at the point G, which causes the slice to fall in two. As for preserving fungi in fluids, I think it in all ways undesirable. It may more or less answer for single or unique specimens, or for large museums, where space is of no consequence; but for all purposes of constant reference and private study, any process of this sort is worthless. Few persons, I imagine, would care to have hundreds (or I might say thousands) of tolerably large glass bottles of fluids in their houses. It is essential that the spores should be secured, as their colour and size are very important. They may be preserved in various ways: if coloured, they are best kept on white paper, and if white, on black glazed paper, such as is supplied to photographers; or they may be at once deposited and kept on glass slides and covered, or between thin sheets of mica, such as photographers use. I prefer the spores free on paper, as they can easily be transferred to glass for examination by breathing on a corner of a glass slide and just touching it on to the dry spores; thousands will attach themselves to the glass, and, moreover, the supply from one fungus appears to be perfectly inexhaustible. To secure a good batch of spores, it is not sufficient to let the Agaric merely rest in the position shown at H ([Fig. 40]), for the spores will not properly fall when this plan is adopted; a far better one is to cut a small hole, about the size of the diameter of the stem of the fungus, in the centre of the paper on which the spores are to be deposited: slip the stem through the hole, carefully draw up the paper collar, and support the fungus in a small pot, glass, or dry phial (placed under a propagating-glass to keep the plant fresh) as shown in [Fig. 41]. If it is wished to fix the spores, let the paper be first washed with a thin solution of gum-arabic, which must be allowed to get perfectly dry; the spores may now fall upon the dry gummed paper; and after the deposition the gummed surface must be breathed upon to moisten the gum, and when it has dried for the second time the spores will be fixed, and not readily rubbed off.
Fig. 38. Specimens showing the gills, rings, and stages of growth.
Fig. 39. Section cut through Agaricus.
Fig. 40.