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Once home always aim at examining the specimens methodically.

The first necessity is to determine whether the fungus, which has been collected, has its spores borne inside a specialised reproductive cell (ascus) i.e. Ascomycete, or on a reproductive cell (basidium) i.e. Basidiomycete. By taking a small piece of the spore-bearing tissue, mounting in water, gently tapping it and examining under a low power of the microscope this can be easily ascertained. The tapping out is best done with the clean eraser of a rubber-topped pencil. There are several different shaped asci and basidia; the latter structures are more important in our study because the Ascomycetes are in the main composed of microscopic members.

The following procedure is necessary for the examination of your find:—

Select a mature cap of an agaric from each collection, cut off the stem and set the cap gills down on white paper, or if the specimen is small or is a woody or toothed fungus, or consists of a club or flattened irregular plate, place the spore-bearing surface (hymenium) face down on a microscope glass slide. The smaller specimens must be placed in tins with a drop of water on the cap to prevent drying out. Even with the larger specimens it is desirable to place a glass slide somewhere under the cap between the gills and the paper, and if possible to enclose the species carefully in waxed paper or in a tin. Whilst you are waiting for the spore-print to form, notes must be made on the more easily observable features; one is not required at this stage to examine the microscopic characters.

All the characters which may change on drying must be noted immediately, and these include colour, stickiness, shape, smell and texture. A sketch, preferably in colour, however rough, can give much more information than many score words.

Cut one fruit-body, longitudinally down with a razor or scalpel or a sharp knife if the fruit-body is woody, and sketch the cut surfaces, fig. 1A-B. These sketches and the rest of the collection notes should be made such that identification and future comparisons can be achieved. Thus always note the characters in the same order for each description. A table of the important characters is provided here, but this is meant as a guide not as a questionnaire. The attachment of the gills, pores or teeth to the fruit-bodies when once the fungus is in section should be always noted (see p. 20).

The spore-print when complete should be allowed to dry under normal conditions and then the spore-mass scraped together into a small pile. A microscope cover-slip should be placed on the top of the pile and lightly pressed down. The colour of the spore-print (or deposit) can then be compared with a standard colour chart and the spores making up the print examined in water under a microscope.