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FUNGI Collection, Description and Preservation of Specimens for deposit at the State Herbarium of South Australia Most fungal fruit bodies comprise more than 90% water and decay rapidly. Preservation requires methods different from those successful for higher plants, pteridophytes, bryophytes and lichens. Though microscopic features are usually retained, many macroscopicfeatures are lost on drying, making it essential to record macroscopic features soon after collection. Collection Specimens must be in good condition, unaffected by bacterial decay or arthropod attack . All stages of development, from primordia (buttons) to fully mature specimens, are collected. Preferably, they are taken from the same mycelium or from a small area. The optimum number of specimens collected varies with size: from at least 5 specimens of large to medium sized (50-200 mm cap diameter) to 50 specimens of very small fruit bodies (1-2 mm). The whole specimen is collected. This may involve careful digging around the base with a knife to ensure the whole of the fruit body is retrieved since the basal structure may be diagnostic for example, in Amanita which has a volva, and species such as Phaeocollybia radicata and Oudemansiella radicata which have a rooting base. Bracket fungi are cut from the bark or log. Soil and grit are removed. The specimens are wrapped in waxed paper or placed in separate plastic containers of the appropriate size. Each collection is labelled with a collection number. Notes are made of features which may rapidly disappear e.g. stickiness. Special collecting techniques are required for truffles. See Castellano et al. (1989) for information. Descriptions of gilled fungi, on return to field
laboratory. Hand drawing of representative  whole specimens, labelled with cap diameter, height, stipe height and
width (at top, middle and at base), position and size of annulus and volva (where present).  specimens cut in half
longitudinally, giving measurements of features listed above, together with gill length and width, depth of flesh, distance
from centre to edge of cap and details of attachment of lamellae/gills.  arrangement of lamellae and lamellulae.
Descriptions of pileus (cap): size, colour (against a standard colour chart [Royal Botanic Garden Edinburgh, 1969, Flora of
British Fungi: Colour Identification Chart, HMSO Edinburgh; Kornerup & Wanscher 1978]), shape, texture, margin and whether
viscid, dry or glutinous, hygrophanous or not. Descriptions of lamellae (gills): colour, attachment to stipe, closeness to each
other, depth, thickness, texture, margin, lamellulae, branching and number. Description of stipe (stem): colour, length at
top, middle and base, shape, texture, whether viscid, dry or glutinous, attachment to stipe, interior structure, consistency .
Descriptions of other macroscopic features (if present): annulus (ring), cortina or its remains, volva . Descriptions of smell,
taste, colour changes on cutting or bruising, exudates, basal mycelia. Records of chemical tests appropriate for the group.
A spore print to record colour of massed spores. The description of fungi without gills e.g. those with pores, tubes or spines,
coral fungi, jelly fungi, puffballs, earthstars, vegetable caterpillars, truffles and Ascomycetes is based on sets of characters
specific to those groups. Many of these characters are also ephemeral and must be recorded shortly after collection. Microscopy. Microscopic examination of specimens follows procedures set out by Largent et al. (1977). Almost all microscopy was carried out on fresh specimens. Where dried material was used, it was rehydrated in 5% aqueous solution of potassium hydroxide (KOH), stained with ammoniacal Congo Red and mounted in 5% aqueous solution of KOH. Sections of ascomycetes were examined separately in water, in 5% aqueous KOH and in Melzer s Reagent. (see project notes for additional details).
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