In canning puff-balls they should be carefully washed and sliced, being sure that they are perfectly white all through. They do not need to stand in salt water before packing in the jar as do those mushrooms which have gills. Otherwise they were canned as the Tricholoma and oyster mushroom. Any edible mushroom can easily be kept for winter use by canning. Use glass jars with glass tops.
TERMS USED
SOME OF THE MOST COMMON TERMS USED. In describing mushrooms it is necessary to use certain terms, and it will be incumbent upon anyone who wishes to become familiar with this part of botanical work to understand thoroughly the terms used in describing the plants.
The substance of all mushrooms is either fleshy, membranaceous, or corky. The pileus or cap is the expanded part, which may be either sessile or supported by a stem. The pileus is not made up of cellular tissue as in flowering plants, but of myriads of interwoven threads or hyphae. This structure of the pileus will become evident at once if a thin portion of the cap is placed under the microscope.
The gills or lamellæ are thin plates or membranes radiating from the stem to the margin of the cap. When they are attached squarely and firmly to the stem they are said to be adnate. If they are attached only by a part of the width of the gills, they are adnexed. Should they extend down on the stem, they are decurrent. They are free when they are not attached to the stem. Frequently the lower edge is notched at, or near, the stem and in this case they are said to be emarginate or sinuate.
Figure 2.—Small portion of a section through the spore-bearing layer of a mushroom which produces its spores on the ends of cells called basidium. (a) Spores, (b) basidium, (c) sterile cells.
In some genera the lower surface of the cap is full of pores instead of gills; in other genera the lower surface is crowded with teeth; in still others the surface is smooth, as in the Stereums. The gills, pores and teeth afford a foundation for the hymenium or fruit-bearing surface. It will be readily seen that the gills, pores and teeth simply expose in a very economical way the greatest possible spore-bearing surface.
If a section of the gills be examined by a microscope, it will be observed that upon both sides of the surface are extended hymenial layers. The hymenium consists of elongated cells or basidia (singular, basidium) more or less club-shaped. Figure 2 will show how these basidia appear on the hymenial layer when strongly magnified. It will be seen that they are placed side by side and are perpendicular to the surface of the gills. Upon each of these basidia are in some species two, usually four, slender projections upon which the spores are produced. In Figure 2 a number of sterile cells will be seen which resemble the basidia except that the latter bear four sterigmata upon which the spores rest. Among these basidia and sterile cells will frequently be seen an overgrown bladder-like sterile basidium which projects beyond the rest of the hymenium, and whose use is not as yet fully known. They are called cystidia (singular, cystidium). They are never numerous, but they are scattered over the entire surface, becoming more numerous along the edge of the gills. When they are colored, they change the appearance of the gills.