Glossary of Terms

This glossary contains mycological terms which may be encountered in the key and in other literature.

adnate (of gills):	attached to the stem for their entire width.
agaric:	a fungus with gills.
adnexed (of gills):	a stem and gill structural arrangement in which the gills just reach the stem.
annual:	a fungus in which the fruiting structure does not disappear after the normal fungus life-time of several hours to several days but instead persists as a fruiting structure for up to a year on the substratum and may continue to produce spores if the weather conditions are suitable. Species of the genus Stereum may do this, although they become very ragged as time passes. Another species that produces long-lived fruiting structures is Schizophyllum commune.
annulus:	the ring on the stem which represents the remnants of the veil in gilled or boletoid fungi.
apothecium (plural apothecia):	the cup or saucer-like fruiting body of an ascomycete. The internal surface of the apothecium is covered by a layer of asci.
arcuate (of gills):	the gill margins are curved and form an arc from the cap margins to the stem; this is an intermediate form between adnate and decurrent.
ascending (of gills):	curving upwards. Usually refers to the situation in which the margins of the gills on the under surface of a conical cap curve upwards to the junction of stem and cap.
ascus:	the club-shaped cell in which spores are formed in ascomycetes. Commonly, there are eight spores per ascus.
autodigestion:	a specialised way of releasing spores used in the genus Coprinus. During spore maturation and release, the fungus uses enzymes to soften and liquefy the spent gill tissue so that the fungus digests itself. The old gill tissues drop away as an inky black fluid and expose the next part of the gills, so that in turn its spores can be released, whereupon it too becomes autodigested.
basidium (plural basidia):	the specialised cell upon which spores are produced in basidiomycetes. The most common number of spores per basidium is four but some puffball species can have up to eight spores per basidium.
bolete (also the term boletus):	used to describe those soft and fleshy fungi, generally found growing on the ground, which have pores under their caps rather than gills. The true boletes are closely related to the agarics.
caespitose:	a growth habit of some fungi in which several stems arise from a common point so that the fungus is clustered. Many wood dwelling species have a caespitose growth habit.
context:	the tissues within a part of the fungus. For mushrooms, toadstools or bracket fungi, the term usually refers to those tissues between the top surface of the cap or bracket and the spore-producing layer underneath.
coralloid :	resembles the structure of branching coral.
cortina:	the cobweb-like veil that extends from the cap margin to the stem in certain agarics, especially the genus Cortinarius. The cortina is generally only visible during the very early stages of the fruiting body's development as it changes from the 'button' stage to the partially expanded stage. Later, it becomes a scattering of fine hairs on the stem and is extremely difficult to recognise.
crowded (of gills):	positioned so close to each other so that they almost touch. See also 'distant'.
decurrent (of gills):	running down the stem.
deliquescence:	the autodigestive (q.v.) process that affects the gills (and often the cap) in the genus Coprinus.
dichotomous :	branching into two more or less equal subbranches or arms.
distant (of gills):	wide apart from each other as distinct from 'crowded' where the gills are so packed that they almost touch. Distant gills are commonly seen in the genera Hygrocybe and Marasmius.
ephemeral:	a fungal fruiting body which lasts for only a very short time, usually only a few hours. Many fungal fruiting structures such as mushrooms have short life spans of perhaps 3ñ7 days. However, in some species (e.g. certain species within the genus Coprinus) the toadstool is produced very early in the morning and has disappeared two hours later. (See also 'annual' and 'perennial'.)
excentric:	a stem arrangement where the stem is not at the centre of the cap but placed to one side.
fibril:	a small hair-like fibre.
fibrillose:	covered with hair-like fibrils.
flocculose:	delicately constructed of fibres like cotton wool.
free (of gills):	totally separate from the stem.
fusiform:	spindle-shaped; narrowing towards both ends.
gasteromycete:	a very broadly defined term for the group of fungi that produce their spores inside a pouch or sack (e.g. puffballs, earthstars and their allies). Originally, the term was used as the name for a class within division Basidiomycota but it is now recognised that the definition is too broad as it includes some fungi that superficially resemble puffballs but which are more closely related to the gilled fungi.
germ pore:	a thin region of a spore wall where the germ tube of the germinating spore will emerge. When present, the germ pore is usually apical.
germ tube:	the small hyphal thread that grows out of a germinating spore.
gill:	one of the vertical plates underneath the cap of a mushroom or toadstool upon which the spores are produced. The scientific term 'lamella' (plural lamellae) is usually found in more specialised works on the higher fungi.
gleba:	the tissue, especially in the puffball or gasteromycete family, that produces the spores.
glutinous:	refers to the fungal surface (generally cap or stem) when it is covered by a thick layer of gluten or slime. This gluten layer makes the cap or stem slippery and often quite sticky so that soil or plant debris sticks fast. The gluten layer can be washed off by heavy rain. (See also 'viscid'.)
gregarious:	growing together in groups, usually of at least 8ñ10 specimens.
hypha:	one of the thread-like filaments which make up a fungal mycelium.
indusium:	the lace-like veil that hangs from the cap in the stinkhorn genus Dictyophora. The veil may be white or coloured (usually yellow or orange) depending upon the species.
lamella	(plural lamellae): the vertical plates that are found beneath the caps of agarics or gilled fungi. In many publications, lamellae are referred to as gills. Specialised cells on the lamellae produce spores.
latex:	the clear or variously coloured fluid that appears when some species of fungi are cut or bruised.
luminescence:	the production of light by a fungus due to the enzymatic combination of two chemicals. As the enzyme splits the chemical bonds in a second substance, light is produced as a by-product. No-one is certain why the fungi produce the light but there is a possibility that it may attract organisms such as snails and slugs which feed on the fungus and then disperse its spores in their droppings. The light can be extremely bright or rather dull, and it may come mostly from the gills or from the entire fungus. Sometimes only the rhizomorphs glow and the rotting log itself may seem to be luminous.
iodine solution:	a solution of iodine crystals and potassium iodide in distilled water; an extremely useful stain for observing spores. Spores with an amyloid reaction become blue to blue-black; spores with no reaction remain colourless or stain a dull, clear brown; spores with a pseudo-amyloid (sometimes called dextrinoid) reaction become deep, dull brick red. Sometimes the spore wall is stained, at other times only the decorative warts, spines, etc. change their colour.
mycelium:	the mass of hyphae that makes up the fungus.
mycology:	the study of fungi.
mycorrhiza:	a fungus-plant relationship. The fungus and the plant engage in a type of partnership and each benefits. The plant obtains extra water and mineral nutrients from the fungus because it can grow very rapidly out into the soil. The fungus takes some of the sugar that the tree manufactures and also obtains shelter inside the root during dry seasons.
parasite:	an organism that uses the living tissues of another organism as food.
perennial:	a fungal fruiting body that remains over a number of years of active growth. Many species of the polypores have perennial fruiting bodies and their large, woody brackets may persist on the tree trunks for a number of years; some have been known to be present for as long as 80 years. Each year the fungus produces a new layer of pores on its undersurface and the margin of the cap grows slightly so that the upper surface has growth zones that can be used to estimate the age of the fungal fruiting body. (See also 'annual' and 'ephemeral'.)
pileus:	the cap of a mushroom- or toadstool-like fungus.
plane:	flat. The term is applied to the caps of gilled fungi when they become quite mature and flat.
plicate:	deeply folded into pleats.
pruinose:	powdery as if flour or dust has been scattered over the surface.
pseudostem:	a false stem produced by some species of fungus in which the true stem has been lost and so the fungus uses a completely different part of itself (such as the cap) to form a false stem which has the same support and nutrient carrying functions as a normal stem. A good example in the key is Calyptella longipes.
punctate	marked with very small spots
reflexed:	depending upon the particular fungal organ, it may mean turned up or turned back.
reticulate:	resembles a net; when referring to spores, it indicates a network of (usually) raised ridges and/or warts on the spore surface.
rhizomorph:	a thickened, thread-like organ consisting of many hyphae running parallel and used by many fungi as a method of covering a considerable distance from one food source to another. Some dangerous plant parasites (e.g. Armillaria luteobubalina) are able to move from one host to another either by direct root contact or by growing rhizomorphs through the soil.
ring:	see 'veil'.
saprophyte:	an organism that uses dead tissues as food. The main litter and wood-recycling fungi of the forests are saprophytes.
septum (plural septa):	a wall or partition across the width of a cell, spore or fungal hypha.
serrate:	sawtoothed; often used to describe edge of gills.
spore:	the reproductive cell of the higher fungi that is similar in its operation to a seed in a flowering plant. Spores are extremely tiny and may be globose, ellipsoidal, polygonal, stellate, cuboid, thread-like or have a more complex shape. Their surfaces may be smooth, spiny, warted, pitted, marked with networks or lines or have various combinations of these decorations. Although there are spores which can survive for many years, many of the spores produced by forest fungi do not live very long because their minute size means that they can store very little food. As a consequence of this, a fungal spore must very quickly find a place in which to grow or it will die.
stem:	the structure upon which the cap of a fungus is carried. The scientific term is ëstipeí. The attachment of the stem may be central, excentric (a little to one side of the centre) or lateral (the stem is placed right at the side of the cap).
stoma (plural stomata):	the distinct opening at the top of a puffball type of fungus through which the spores escape. Stomata are found in genera such as Lycoperdon and Geastrum. (Not to be confused with the terms 'stomate' and 'stomata' as applied to the openings in leaves of higher plants.)
stria (plural striae):	a narrow band, streak or stripe of distinctive colour, or a groove or ridge on a surface, e.g. spores of some boletoid species exhibit surface striae. The word striation is often used interchangeably.
striate:	marked with delicate lines, grooves or ridges. This term is frequently applied to the radial or marginal striations that occur on the caps of various macrofungi.
striation:	see stria.
strigose:	with straight, sharp-pointed hairs.
stroma (plural stromata):	a fungal structure which supports the true fruiting structure on it or inside it. Stromata are sometimes found in ascomycetes (e.g. Cordyceps and Daldinia). When a stroma is formed, the actual fruiting bodies are usually tiny, pear-shaped flasks that are either partially or wholly embedded in the surface of the stroma. These true fruiting structures can be seen with a hand lens. In effect, the stroma is acting like a giant 'stem' to hold the fruiting structures safely.
substratum:	the surface upon which the fungus is growing; e.g. wood, humus, soil, moss, litter, etc.
tubercule:	a small, usually rounded, wart-like outgrowth. The marginal striations on the cap of species in the genus Russula are often tubercular.
umbonate:	referring to a cap structure in which the centre of the cap has a distinct bump or 'umbo' which projects as a central lump above the remainder of the cap.
universal veil:	a thin membrane which at first entirely encloses the immature fungus. The universal veil is ruptured by the fruiting body expansion and is left as fragments and/or a volva. Universal veils can be membranous or very friable and then persist only as scattered fragments which are very hard to recognise.
veil:	a thin membrane that extends from the edge of the cap in an agaric (and in some boletes) to the stem and protects the gills when they are first forming. The common field mushroom is a species that produces a good example of a veil. If the veil leaves a residue on the stem, it is usually referred to as a ring or annulus. (See also 'cortina'.)
verrucose:	a term generally applied to spores in which the outer surface is ornamented with tiny, rounded warts.
verruculose:	very delicately verrucose.
viscid:	the fungal surface (generally cap or stem) is sticky, slippery and appears to be covered in a very thin layer of slime. (See 'glutinous'.)
volva:	the cup-like structure left at the base of the stem in some species of gilled fungi and gasteromycetes. The volva is the remnant of the universal veil which at first completely enclosed the immature fungus. Sometimes the volva may be partially buried and great care must be exercised to ensure that its presence is recognised.