The fruit-body is _angiocarpic_, fleshy at first, and later generally
more or less _hard_ and _continues closed after the_ spores _are
ripe_. The tissue lying immediately inside the _peridium_ is termed
the _gleba_; it is porous, containing a larger or smaller number of
chambers lined with the hymenium, which is either a continuous layer of
basidia or else it fills up the entire cavity. The basidia as a rule
bear four spores, sometimes eight (_Geaster_), or two (_Hymenogaster_).
The tissue of the walls (_trama_) consists often (_Lycoperdaceæ_)
of two kinds of hyphæ, some thin and rich in protoplasm, divided
by transverse septa and bearing the basidia; others thicker and
thick-walled which do not dissolve like the former on the ripening of
the spores, but continue to grow and form a woolly, elastic mass, the
_capillitium_, which may be regarded as highly developed paraphyses.
The peridium may be either single or double, and presents many
variations in its structure and dehiscence. The mycelium is generally a
number of string-like strands, living in soils rich in humus.
Order 1. =Tylostomaceæ.= Capillitium present. After the rupture
of the peridium the remaining part of the fruit-body is elevated
on a long _stalk_. _Tylostoma mammosum_, on heaths.
Order 2. =Lycoperdaceæ.= The fruit-body has a double peridium; the
external one at length breaks into fragments (_Lycoperdon_, _Bovista_),
or it has a compound structure of several layers (_Geaster_) and
detaches itself as a continuous envelope from the inner layer, which
is membranous and opens at its apex. The interior of the fruit-body
consists either solely of the fertile gleba (_Bovista_, _Geaster_),
or, in addition, of a sterile tissue at the base (_Lycoperdon_). A
capillitium is also present.
[Illustration: FIG. 180.--_Lycoperdon gemmatum_ (½ nat. size).]
_Lycoperdon_ (Puff-ball) has a sterile part at the base of the
fruit-body which often forms a thick stalk. The surface of the
peridium is generally covered with warts or projections. When
young this Fungus is edible, but when ripe it is dry, and used
for stopping the flow of blood. _L. giganteum_, which is often
found growing in meadows, attains a considerable size, its
diameter reaching as much as eighteen inches. _L. gemmatum_
(Fig. 180) is covered with pyramidal warts; in woods.--_Bovista_
has no sterile basal part; the external peridium is smooth, and
falls away in irregular patches. _B. plumbea_, on links near the
sea.--_Geaster_ (Earth-star) has an external peridium composed
of several layers, which when the fruit-body opens, split into
several stellate segments. These segments are very hygroscopic,
and in dry weather bend backwards and so raise the inner
peridium into the air. The inner peridium contains the spores
and capillitia. _G. coliformis_ has several apertures in the
inner peridium. The other species have only one regular aperture
at the apex. _G. striatus_ has a pedicellate inner peridium,
with conical, striped peristome. _G. fornicatus_ has an external
peridium split into four segments. This last and several other
species produce “mycorhiza” on the roots of Conifers.
[Illustration: FIG. 181.--I _Hymenogaster citrinus_ (nat. size);
II longitudinal section through _H. tener_ (× 5); III portion of
a section of _H. calosporus_; _g_ a chamber; _h_ hymenium; _sp._
spores; _t_ trama (× 178); IV _Rhizopogon luteolus_ (nat. size);
V _Scleroderma vulgare_, VI section of V; VII basidia with spores
belonging to the same Fungus.]
Order 3. =Sclerodermataceæ.= _Capillitium_ wanting. The peridium is
simple and thick, gleba with round, closed chambers, which are filled
with basidia.
_Scleroderma_ has a corky peridium. The fruit-bodies commence
their development under ground. _S. vulgare_ (Fig. 181 V-VII),
has a hard, slaty-black gleba.
Order 4. =Nidulariaceæ= (=Nest-Fungi=). Small Fungi of which the
fruit-body at first is spherical or cylindrical but upon maturity
it becomes cupular or vase-like, and contains several lenticular
“peridiola” lying like eggs in a nest. The peridiola are the chambers
which contain the hymenium, covered by a thin layer of the gleba, all
the remaining portion of the gleba becoming dissolved. On decaying wood.
_Nidularia_ has spherical fruit-bodies containing a
large number of lenticular peridiola, embedded in a slimy
mass.--_Crucibulum_ has fruit-bodies resembling crucibles
with discoid peridiola, each with a spirally-twisted
stalk.--_Cyathus_ has a fruit-body, which when open is
campanulate, with stratified peridium, and long-stalked,
lense-shaped peridiola.
Order 5. =Hymenogastraceæ.= Fruit-bodies tubercular, globose and
subterranean, resembling very closely the Truffles, from which they
can only be distinguished with certainty by microscopic means. The
peridium is simple, capillitium wanting, and the gleba encloses a
system of labyrinthine passages covered with a continuous hymenium.
The fruit-bodies persist for some time, and form a fleshy mass, the
spores being only set free by the decay of the fruit-body, or when it
is eaten by animals. The majority are South European. _Hymenogaster_,
_Melanogaster_, _Rhizopogon_ (Fig. 181 I-IV).