These spore-deposits are of course fugitive, and will easily rub off at the slightest touch. But inasmuch as many of these specimens, either from their beauty of form or exquisite color, or for educational or scientific purposes, it will be desirable to preserve, I append simple rules for the making of the prints by a process by which they will become effectually "fixed," and thus easily kept without injury.
DIRECTIONS FOR MAKING A MUSHROOM SPORE-PRINT
Take a piece of smooth white writing-paper and coat its surface evenly with a thin solution of gum-arabic, dextrine, or other mucilage, and allow it to dry. Pin this, gummed side uppermost, to a board or table, preferably over a soft cloth, so that it will lie perfectly flat. To insure a good print the mushroom specimen should be fresh and firm, and the gills or spore-surface free from breaks or bruises.
Cut the stem off about level with the gills, then lay the mushroom, spore-surface downward, upon the paper, and cover with a tumbler, finger-bowl, or other vessel with a smooth, even rim, to absolutely exclude the slightest ingress of air.
After a few hours have passed by, perhaps even less, the spores will be seen through the glass on the paper at the extreme edge of the mushroom, their depth of color indicating the density of the deposit. If we now gently lift the glass, and with the utmost care remove the fungus, perhaps by the aid of pins previously inserted, in a perfectly vertical direction, without the slightest side motion, the spore-print in all its beauty will be revealed—perhaps a rich brown circular patch with exquisite radiating white lines, marking the direction and edges of the gills, if an Agaric; perhaps a delicate pink, more or less clouded disk, here and there distinctly and finely honey-combed with white lines, indicating that our specimen is one of the polypores, as a Boletus. Other prints will yield rich golden disks, and there will be prints of red, lilac, greens, oranges, salmon-pinks, and browns and purples, variously lined in accordance with the number and nature of the gills or pores. Occasionally we shall look in vain for our print, which may signify that our specimen had already scattered its spores ere we had found it, or, what is more likely, that the spores are invisible upon the paper, owing to their whiteness, in which case a piece of black paper must be substituted for the white ground, when the response will be beautifully manifest in a white tracery upon the black background. One of these, from the Amanita muscarius, is reproduced in our illustration. If the specimen is left too long, the spore-deposit is continued upward between the gills, and may reach a quarter of an inch in height, in which case, if extreme care in lifting the cap is used, we observe a very realistic counterfeit of the gills of the mushroom in high relief upon the paper. A print of this kind is of course very fragile, and must be handled with care. But a comparatively slight deposit of the spores, without apparent thickness, will give us the most perfect print, while at the same time yielding the full color. Such a print may also be fixed by our present method so as to withstand considerable rough handling, all that is required being to lay the print upon a wet towel until the moisture has penetrated through the paper and reached the gum. The spores are thus set, and, upon drying the paper, are quite securely fixed. Indeed, the moisture often exuded by the confined fungus beneath the glass proves sufficient to dampen the mucilage and set the spores.
A number of prints may be obtained from a single specimen.
To those of my readers interested in the science of this spore-shower I give sectional illustrations of examples of the two more common groups of mushrooms—the Agaric, or gilled mushroom, and the Polyporus, or tube-bearing mushroom. The entire surface of both gills and pores is lined with the spore-bearing membrane, or hymenium, the spores falling directly beneath their point of departure as indicated; in the case of the Agaric, in radiating lines in correspondence with the spaces between the gills, and in Polyporus in a tiny pile directly beneath the opening of each pore.