This family is very rich in species (more than 8000 have been
described), and to it belong all the “Mushrooms” and “Toadstools.”
The _fruit-bodies_ present very various forms; they are generally
fleshy, very perishable, seldom leathery or corky, in the last case
often perennial. The _basidia_ are more or less _cylindrical_ and bear
_generally_ 4 (seldom 2, 6 or 8) _sterigmata and basidiospores_. The
hymenium in the fully-formed fruit-bodies lies free on the surface: in
orders 1 and 2 and a portion of order 6 it is from the commencement
exposed, fruit-bodies _gymnocarpic_; orders 3–6 have _hemiangiocarpic_
fruit-bodies (p. 157). In the first order the basidia (or the
hymenium) are developed immediately from the mycelium (Fig. 163); the
fruit-bodies of orders 2 and 3 present a higher grade of development,
and have between the mycelium and hymenium a special hyphal-tissue,
a _stroma_, which is crustaceous, club-like, or coralloid, etc.,
and in general bears the hymenium on the largest part of the free,
smooth surface. In the forms most highly developed (orders 4–6) a
new tissue--the _hymenophore_--is introduced between the stroma and
hymenium, which appears on the under side of the fruit-body in the
form of warts, projections, tubes, folds or lamellæ (Figs. 166, 167,
174 _bc_). _Paraphyses_ are frequently found in the hymenium, among
the basidia. In the Hymenomycetes few examples of _conidia_ can be
recognised at first. More frequently _chlamydospores_ are found,
particularly _oidia_. The _mycelium_ is richly branched, generally
colourless, often perennial; it lives in humus or decaying wood, and is
seldom parasitic. The hyphæ generally have clamp-connections and unite,
sometimes, to form a rhizomorpha (Fig. 177) or sclerotia with coloured,
pseudo-parenchymatous covering.
[Illustration: FIG. 163.--_Exobasidium vaccinii._ I
Hypertrophied stem of _Vaccinium vitis idæa_; II leaf with
gall-like swelling; III section of II; IV transverse section: _m_
mycelium between the parenchymatous cells; _p_ hypodermal cells;
_e_ epidermis with basidia in various stages of development; V
epidermis with germinating spores; VI and VII spores germinating
in water (IV-VII × 620).]
Order 1. =Tomentellaceæ.= To this order belong the simplest of the
Hymenomycetes. The basidia (Fig. 145) arise free and irregularly
from the mycelium; a _hymenium_ is _entirely absent_ or _very
slightly formed_ (in _Corticium_ it attains its highest development);
_fruit-bodies_ are _also wanting_.--In general they form flaky,
membranous or leathery coverings on bark and wood. Some are parasites.
_Hypochnus_ without conidia.--_Tomentella_ with conidiophores;
growing on wood or earth.--_Exobasidium vaccinii_ (Fig. 163),
a parasite on _Vaccinium_, _Andromeda_, _Arctostaphylos_, and
_Rhododendron_, forms flaky-powdery, white or red coverings and
may cause hypertrophy of the parts attacked. _E. warmingii_ is
parasitic on _Saxifraga_; _E. lauri_ causes outgrowths on the
stem of _Laurus canariensis_ as long as a finger, which formerly
were regarded as aerial roots.--_Corticium_ forms membranous
to leathery layers or crusts; _C. quercinum_ on wood and bark,
particularly Oak, is flesh-coloured; _C. cæruleum_ has a blue
hymenium; _C. giganteum_ on the bark of fallen Pine-trees.
Order 2. =Clavariaceæ.= The hymenium is situated on a stroma, and
either completely _covers the smooth surface_ of the more or less
fleshy _gymnocarpic fruit-body_, or is confined to a tolerably well
defined _upper portion_ of it (_Typhula_). Paraphyses absent. The
vertical, white, yellow, or red fruit-bodies are roundish or club-like,
undivided or richly branched (Fig. 125). Generally on the ground in
woods, seldom on tree-stems, etc.
[Illustration: FIG. 164.--_Clavaria coralloides_ (nat. size).]
GENERA: _Clavaria_, generally large Fungi with thick, round
branches. _C. botrytis_ has a very thick, tubercular stem with
numerous short, flesh-coloured branches: it has an agreeable
taste. _C. coralloides_ has a brittle, richly-branched
fruit-body (Fig. 164); basidia with two large spores. _C.
pistillaris_ consists of a single, undivided club of a
yellowish-white colour.--_Sparassis_ has compressed, leaf-like,
curled branches; _S. crispa_ has fruit-bodies as large as
a white cabbage-head, with an agreeable taste.--_Typhula_
and _Pistillaria_ are small Fungi with filamentous stalks,
terminating in a small club. The fruit-bodies of the former
often arise from a small, spheroid sclerotium; the latter is
distinguished by the basidia bearing only two spores.
Order 3. =Thelephoraceæ.= The hymenium is placed on a stroma and
_covers the smooth surface_ of the leathery _hemiangiocarpic
fruit-body_, generally _on its under side_. The edge of the stroma,
which bounds the hymenium, is sometimes especially developed
(_Stereum_). Saprophytes.
GENERA: _Thelephora_. The fruit-bodies in this genus are brown,
very irregularly shaped, and often lobed. The spores too are
brown, but in the other genera colourless. The species are found
growing on barren soil. _T. laciniata_ (Fig. 165) has imbricate,
semicircular, dark-brown pileus, which is jagged at the edge
and upper surface. The fruit-bodies are very often raised above
the ground, and although this species is not a parasite, yet
it destroys young seedlings by growing above and smothering
them.--_Stereum_ has a stiffer fruit-body, with a distinct,
fibrous, intermediate layer. It grows on bark and wood,
projecting like a series of imbricate brackets. _S. hirsutum_
is yellow; its free edge is provided with a number of stiff
hairs, the upper surface being divided into a number of zones.
_S. purpureum_ has a red-violet hymenium which distinguishes
it from the previous species.--_Cyphella_ has a membranous
cup- or bell-shaped fruit-body, often borne on a stalk, the
concave surface being covered with the hymenium. They are small,
white Fungi, growing on Moss and dead stems.--_Solenia_ is
closely related to _Cyphella_; its fruit-bodies are smaller and
hairy; they are found clustered together forming a crust-like
covering on dead wood.--_Craterellus_ has a large, funnel-shaped
fruit-body, the hymenium covering the external surface.
_C. cornucopioides_ is shaped like a trumpet or a “horn of
plenty.” It is dark-grey, several inches in height, and grows
gregariously on the ground in forests. It is distinguished by
the basidia bearing only two sterigmata.
[Illustration: FIG. 165.--_Thelephora laciniata_ (nat. size).]
Order 4. =Hydnaceæ.= The fruit-body is most frequently fleshy, and
varies considerably in shape, the simplest forms being resupinate,[14]
the higher ones umbrella-like. The _hymenophore_ is found on the
free or downward-turned surface, and always takes the _form of soft
emergences_ hanging vertically downwards. The emergencies may be
thorn-, awl-, or wart-like. The species are found growing on the soil
and on dead wood.
GENERA: _Hydnum_ has subulate, distinct emergences. _H.
repandum_ is yellow, the stalk being placed in the centre of the
pileus. It is an edible species, and often forms “fairy rings”
in woods. _H. auriscalpium_ (Fig. 166) is dark-brown, with stalk
placed at the edge of the pileus. It grows on old Fir-cones. _H.
erinaceus_ grows on old tree-trunks. The fruit-body is yellow
and very large--as big as a human head--with emergences as much
as an inch in length.--_Irpex_ has a leathery fruit-body, partly
resupinate, partly with free, projecting edge; the under side
bears tooth-like emergences which are arranged in rows, and
_Irpex_ thus forms a transition to the Agaricaceæ.--_Phlebia_
is entirely resupinate, with radially-arranged folds on the free
side, and pectinate border.
[Illustration: FIG. 166.--_Hydnum auriscalpium_, upon a Fir-cone,
in different stages of development.]
Order 5. =Polyporaceæ (Pore-Fungi).= An order very rich in species
(about 2000 species are described). The fruit-body is of very
different forms--resupinate, projecting like a bracket, hoof-like, or
umbrella-shaped. In some it is fleshy and edible, in others leathery or
corky, persisting for several years. The hymenophore is situated on the
under side of the fruit-body, and consists of wide or narrow _tubes_ or
_pores_, whose inner surface is clothed with the hymenium (Fig. 167).
In some fruit-bodies large cavities are to be found, which have arisen
as interstices between the labyrinthine curved and reticulate folds.
Chlamydospores are known in some species. Conidia occur very rarely.
Many species work considerable damage: some as parasites on trees,
others by destroying timber.
[Illustration: FIG. 167.--_Polyporus igniarius._ Section through
the under side of the Fungus: _h-h_ is hyphal-tissue between the
tubes, formed by irregularly felted hyphæ, many of which are seen
cut across; _s_ is the hymenium which covers the walls of the
tubes, and from which the basidia with the spores protrude.]
GENERA. _Polyporus_ (Pore-Fungus). The tubes are narrow,
accurately fitted together, and forming a thick layer on the
under side of the fruit-body, appearing as a number of fine
holes. The fruit-body most frequently resembles a bracket, or
is hoof-shaped, with one side growing from a tree-trunk; it
is very often perennial, and a new layer of tubes arises in
each succeeding period of vegetation. Strata, corresponding
to the periodically interrupted growth, are thus formed in
storeys one above the other, and are visible on the upper
surface of the fruit-body, as well as in the interior, as a
series of concentric belts, sometimes as many as half a score
or more in number. _P. fomentarius_ (Touchwood) attacks
trees, especially the Beech. The spores germinate on wounds
from broken branches, and the hyphæ, following the course of
the medullary rays, find their way into the interior of the
tree, from whence the mycelium spreads upwards, downwards, and
peripherally, so that the wood becomes rotten (“white-rot”) and
thick felts of mycelium are formed in radial and tangential
directions. A dark line, caused by the youngest parts of the
hyphæ containing a brown juice, marks the boundary between
the rotten and the unattacked parts of the stem (Fig. 168);
at places where the mycelium extends to the bark, the cambium
becomes destroyed and further growth is arrested, so that
longitudinal furrows arise on the stem. It is at these places,
too, that the hoof-shaped, ash-coloured fruit-bodies are
developed, which may attain a circumference of upwards of 7
feet. The interior of the fruit-body consists of a dried-up,
loosely felted, red-brown mass of hyphæ, which has been used for
tinder and as a styptic (“Fungus chirurgorum”). _P. igniarius_
has a harder, dark-brown, more rounded fruit-body; it grows in
a similar manner, but especially attacks Oaks, Poplars, and
Plum-trees, the wood of which becomes rotten, and is called
touchwood. _P. pini_ (_Trametes pini_), (Fig. 170), a parasite
on the stems of _Pinus_, causes a kind of “red-rot” in the
stem. _P. sulphureus_ has a soft, cheesy, yellow fruit-body;
it produces “rot” in Oaks and Apple-trees. _P. officinalis_,
Larch-fungus (“Fungus Laricis” in Pharmocopœia), grows on
Larch-trees in the south-east of Europe. _P. versicolor_ has
thin, semicircular fruit-bodies, with zones of various colours
on the upper side; it is one of the most frequent species on
tree-stems. _P. frondosus_ grows on soil in woods, and consists
of numerous aggregated fruit-bodies, which become very large
and fleshy. This species is edible. _P. perennis_ also grows on
the soil in woods; it is very leathery, with central stalk, and
has concentric zones on the upper surface of the fruit-body.
_P. vaporarius_ destroys the wood of living Pines (_Pinus
silvestris_) and Firs (_Picea excelsa_), causing it to become
red-brown; in timber this Fungus causes “red-strip” followed by
a “dry-rot.” _P. squamosus_ destroys many Walnut-trees, and is
also very destructive to Limes and Elms. _P. fulvus_ causes a
“white-rot” in _Abies alba_.
[Illustration: FIG. 168.--Section of stem of a Beech attacked by
_P. fomentarius_: _a_ non-attacked parts of the stem; _b_ the
furrows where the mycelium has reached the bark, and where the
thick mycelium-strands reach the exterior (⅙th of the nat. size).]
[Illustration: FIG. 169.--Base of a Fir-tree, with a number of
fruit-bodies of _Heterobasidion annosum_ just beneath the surface
of the soil, indicated by the dotted line (¼th nat. size).]
[Illustration: FIG. 170.--A fully developed fruit-body of
_Polyporus pini_ (_Trametes pini_), lateral view (nat. size).]
_Heterobasidion annosum_ (_Polyporus annosus_, _Trametes
radiciperda_, Fig. 169) is characterized by its
_Aspergillus_-like conidiophores. It is a parasite on the
Pine, Fir, Birch, Beech, etc., and is the chief cause of a
root-disease (red-rot) in Pines and Firs; the fruit-bodies
develope a large number of basidiospores; they may be very large
and are found just beneath the surface of the soil (on living or
dead roots), and exposed to the air (on felled stems and roots,
in Scandinavia).
_Ptychogaster_ has cushion-like fruit-bodies, which consist
chiefly of chlamydospore-chains, formed of ellipsoidal spores,
which alternate with short hyphæ having transverse septa and
clamp-connections. The hymenial portion is limited to a small
group of tubes. _Pt. albus_ (_Oligorus ustilaginoides_) grows
on stumps of Conifers and forms irregular cushions, at first
white and later on brown, which consist almost entirely of
chlamydospores.
_Boletus_ (Fig. 171) has a fleshy fruit-body resembling a common
Mushroom, with central stalk. The layer of tubes is easily
detached from the pileus, and the tubes are easily separable
from one another. They grow on the ground in woods. Edible
species are: _B. edulis_, with thick, reticulate stalk; _B.
scaber_, with thin stalk and rough pileus; _B. luteus_, with a
ring on the stalk. _B. luridus_ is poisonous, its tubes have
red openings, and the flesh turns quickly blue when broken and
exposed to the air.
_Fistulina hepatica_ (Beef-steak Fungus), has a red, fleshy,
edible fruit-body, with red juice. The tubes are individually
distinct; conidia are also developed. Grows on old Oaks.
_Merulius lacrymans_ (“Dry-rot”) has a resupinate fruit-body
with white, cotton-like border, and the remaining portions
covered by reticulate, ramified veins of a rust-brown colour.
In favourable vegetative conditions it is fleshy and exudes
large drops of water--hence its specific name and also the name
“Tear Fungus.” The mycelium is at first colourless, and then
yellow-brown; when dry it is tough and leathery. It destroys
the timber in damp houses, extends far and wide over boards and
beams and even over the masonry, giving rise to a disagreeable
smell in the rooms in which it lodges. In woods the Fungus lives
on Pine-stems. It is brought from the forest on the logs of
timber, and is distributed from log to log by the mycelium and
the basidiospores. The living mycelium can be recognised by the
clamp-connections shooting out branches. The basidiospores are
often ejected a distance of a metre; they are elliptical (10–11µ
long and 5–6µ broad), and germinate easily on damp wood, or in
fruit-juice which has been neutralized with urine or alkaline
carbonates.
_Dædalea_ (Labyrinth Fungus), has bracket-like, corky
fruit-bodies with irregularly-folded plates or discs on the
under side. It forms a transition to the Agaricaceæ. _D.
quercina_ is frequent on Oak-stumps.
[Illustration: FIG. 171.--_Boletus edulis_ (about ¼th): _b_
longitudinal section of a portion of the pileus.]
Order 6. =Agaricaceæ= (=Mushrooms=, =Toadstools=). _The hymenophore
consists_ of knife-like plates (_lamellæ_, _gills_), which are situated
on the under side of the umbrella-like pileus of the fruit-body, and
radiate from the central stalk. Those which are first formed extend
from the edge of the pileus to the stalk; those formed later reach only
a longer or shorter portion of this distance, according to their age.
In structure the lamellæ (Fig. 174) consist of a central mass of hyphæ,
the _trama_, continuous with the hyphæ of the pileus; these terminate
in a layer of shorter cells, the _subhymenial layer_, immediately
beneath the hymenium which is composed of basidia and paraphyses. In a
few species, but not in the majority, the lamellæ are branched, and in
some they are decurrent. A few have the stalk placed excentrically, or
it may be entirely absent.
[Illustration: FIG. 172.--Development of _Psalliota campestris_:
_a_, _b_, _c_, _d_ show the various stages of the development
of the fruit-bodies and the mycelium (_m_) (nat. size); _e_ the
fruit-body in a somewhat later stage, slightly magnified; _f_
longitudinal section of _e_; _n_ first formation of the hymenium;
_g_ longitudinal section of a more advanced fruit-body (nat.
size); _n_ the hymenium; _o_ velum partiale (see Fig. 133.)]
In the early stages of its development the fruit-body is more or
less enclosed in a hyphal tissue--the “veil” (_velum universale_, or
_volva_). The veil at first completely encloses the young fruit-body,
but is afterwards ruptured as the latter grows, part remaining at the
base of the stalk as the “sheath” (_annulus inferus_), and part on the
pileus as scales or warts. In the “Fly Mushroom” (_Amanita muscaria_)
the remains of the veil are especially conspicuous as white patches
on the bright red ground of the upper surface of the pileus, and as
a sheath at the base of the stalk (Fig. 178 _v._). Another veil--the
_velum partiale_--a hyphal tissue (Figs. 178 _a_; 173) stretches from
the edge of the pileus to the stalk, and encloses the lamellæ. This
veil is ruptured as the pileus expands, a portion attached to the stalk
remaining as the “upper ring” (_annulus superus_) (Figs. 173, 178 _a_),
or a part attached to the pileus hanging down as a fringe round its
edge.--Some genera have no veil, the under side of the pileus being
exposed from the first (_gymnocarpic_ Agaricaceæ). Those which have
a veil (_hemiangiocarpic_ A.) afford a transition to the angiocarpic
Gasteromycetes.
[Illustration: FIG. 173.--The cultivated Mushroom (_Psalliota
campestris_).]
The mycelium mostly grows in soils rich in humus or dung, on decaying
trees and similar objects. Many species, _e.g. Tricholoma personatum_
and _Marasmius oreades_, form the so-called “fairy rings.” The
fruit-bodies in these species are confined to a larger or smaller
surface on which they are very regularly arranged in a ring. The reason
for this is found in the radial growth of the mycelium, so that the
oldest portion, or the starting point, is found at the centre of the
ring, and the younger ones, on which the fruit-bodies are formed, at
the circumference. The older hyphæ gradually die, and at the same time,
the radial growth continuing, the ring of fruit-bodies becomes larger
and larger. The “fairy-rings” are marked not only by the fruit-bodies,
but also by the more vigorous growth and darker colour of the grass
upon these spots.
Some species are _parasites_. An example is presented by _Armillaria
mellea_, a remarkable and very destructive Fungus in woods and forests
(Figs. 176, 177). ~In addition to the filamentous, white mycelium,
it has also black, or black-brown, horny, root-like mycelium-strands
(rhizomorpha) which were formerly considered to belong to a special
genus of Fungi described under the name “_Rhizomorpha_.” The mycelium
lives parasitically on the Conifers and other trees, forcing its hyphæ
into the bark and between the bark and wood, and thence penetrating
into the wood so that the tree is very severely attacked. It may also
live saprophytically, and clusters of fruit-bodies are often found on
old stumps and stems, on old timber, and in the rich soil of woods. The
rhizomorpha, living underground, can extend for considerable distances
and infect the roots of neighbouring trees, and spreads in this way
the diseases known as “Harzsticken” and “Bark-Canker,” which are very
destructive to young trees.~
[Illustration: FIG. 174.--_Psalliota campestris. A_ Tangential
section of pileus showing lamellæ (_l_). _B_ Portion of gill
more highly magnified; _t_ trama; _hy_ hymenium with basidia and
basidiospores; _sh_, subhymenial layer. _C_ A portion of the same
more highly magnified; _s′ s′′ s′′′ s′′′′_ various stages
in the development of basidiospores; _q_ paraphyses.]
The chief characteristics by which the numerous genera are separated
are the presence or the absence of the two kinds of veils, the nature
of the fruit-body, the form, branching of the lamellæ, and their
position and relation with respect to the stem, the shape of the
pileus, the colour of the spores, etc., etc. A knowledge of the colour
may be obtained by placing the pileus with the lamellæ turned downwards
on a piece of white or coloured paper, so that the spores, as they fall
off, are collected on the paper, and the arrangement of the lamellæ can
then be clearly seen.
[Illustration: FIG. 175.--_Cantharellus cibarius_ (reduced).]
[Illustration: FIG. 176.--_Armillaria mellea._ (½ nat. size): _a_
root of a Fir; _b_ rhizomorpha-strands; _c-f_ fruit-bodies in
four different stages of development.]
[Illustration: FIG. 177.--The mycelium of _Armillaria mellea_
(“_Rhizomorpha_”) (nat. size).]
About 4,600 species belonging to this order have been described.
On account of the large number of species the order is divided
into several sections:
1. =Agaricinei=; fruit-body fleshy; lamellæ membranous,
knife-like, with sharp edge; basidia crowded together. The
FOLLOWING HAVE WHITE SPORES:--_Amanita_ (Fly Mushroom), with
volva, and generally also the upper ring on the stalk; many are
poisonous, such as _A. muscaria_ (Fig. 178) which has bright red
pileus with white spots, _A. pantherina_ and _A. phalloides_;
_A. cæsarea_ is edible.--_Lepiota procera_ (Parasol Fungus)
is one of the largest Mushrooms; it has a scaly pileus and
moveable ring (edible).--_Armillaria mellea_ has been mentioned
above (Figs. 176, 177).--_Tricholoma_, lamellæ indented near
the stalk; _T. gambosum_ (Pomona Fungus) belongs to the best
of edible Fungi; _T. personatum_ often forms fairy rings (see
above).--_Clitocybe_, lamella decurrent; _C. nebularis_ is
edible.--_Pleurotus_, stalk eccentric; _P. ostreatus_ (Oyster
Mushroom) grows in clusters on tree-stems (edible).--_Collybia_
and _Mycena_, species numerous, small.--SPORES ROSE-RED:
_Volvaria_ and _Hyporhodius_.--SPORES BROWN: _Cortinarius_,
with cobweb-like veil; _Pholiota_, membranous veil and ring;
_P. squarrosa_ in clusters on tree-stems; _P. mutabilis_, on
tree-stumps (edible).--SPORES VIOLET-PURPLE: _Hypholoma_,
_Psalliota_; to this section the common edible Mushroom (Fig.
172–174) belongs, with annulus and chocolate-coloured lamellæ;
it is cultivated for the sake of the fine flavour.--SPORES
BLACK: _Coprinarius_.
[Illustration: FIG. 178.--Fly Mushroom (_Amanita muscaria_).]
2. =Marasmiei.= Fruit-body tough, almost leathery, and
persistent; spores white. _Marasmius oreades_ forms large,
regular fairy-rings on pastures and commons; it is used as
seasoning in food.--_Panus stipticus_ with eccentrically-placed
stalk, in clusters on tree-stumps.--_Schizophyllum_ has the edge
of the lamellæ divided longitudinally, and the split portions
revolute.--_Lentinus_ affords a transition to _Dædalea_ among
the Polyporaceæ.
3. =Russulei.= Fruit-body fleshy and fragile, in which two
different systems of hyphæ may be distinguished; spores thorny,
white, or pale-yellow. Many are poisonous.--_Russula_ has
generally fragile and thick lamellæ reaching from stalk to edge
of pileus; pileus frequently red.--_Lactarius_ has white or
yellow milky juice, which often is very acid. _L. deliciosus_
has red-yellow milky juice, and is of a pleasant flavour. _L.
torminosus_ is poisonous.
4. =Hygrophorei.= Lamellæ thick and waxy, widely separated;
spores white. Many species of _Hygrophorus_ have
brightly-coloured pileus and grow among the grass on moors and
commons.--_Nyctalis_ is parasitic on larger Toadstools. It is
remarkable for its abundant formation of chlamydospores, whilst
the basidiospores are little developed.
5. =Coprinei.= Fruit-bodies very soft, quickly perishable;
lamellæ membranous and deliquescent. The basidia are separated
from each other by paraphyses. _Coprinus_ has coal-black spores,
grows on manure, and sometimes developes sclerotia.
6. =Paxillei.= Fruit-body fleshy; lamellæ easily detached from
the pileus and reticulately-joined near the stalk. They form a
connecting link between the Agaricaceæ and _Boletus_.
7. =Cantharellei.= Lamellæ reduced to dichotomously-divided
folds, decurrent on the stalk. _Cantharellus cibarius_ (Fig.
175) is yolk-yellow, and grows on the ground in woods (edible).
It is allied to _Craterellus_.