Introduction to Fungi, Third Edition

GASTEROMYCETES IN THE EUAGARICS CLADE
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Fig 20.3 Lycoperdon pyriforme. (a) L.S. gasterocarp. (b) Portion of peridium and gleba. Note the pseudoparenchymatous
exoperidium and the fibrous endoperidium. (c) Portion of gleba showing basidia, thin-walled hyphae and capillitium threads.
grown on a mixture of cow dung and straw
is covered with a thin layer of casing soil and
then left at room temperature for a few weeks
(Fig. 20.2d; Webster & Weber, 1997). The fungus
can also fruit on agar media (Lu, 1973). Light is
essential for fruit body formation. Since the
peridioles retain viability for many years if
frozen, C. stercoreus provides a convenient example
to study.
The first sign of fruit body development is the
appearance of brown mycelial cords at the soil
surface, on which knots of hyphae differentiate.
In young gasterocarps, the mouth of the funnel
is closed over by a thin papery epiphragm
(Figs. 20.2d, 20.4a) which ruptures as the fruit
body expands. Within the funnel, the peridioles
develop. They are lens-shaped, slate-blue in
colour and attached to the peridium by a
complex funiculus. In earlier stages of development
in this and other species of Cyathus, the
peridioles are separated by thin-walled hyphae
which disappear at maturity (Walker, 1920). The
peridiole wall consists of an outermost layer
(tunica) made up of loosely interwoven hyphae,
a dark cortex, and an inner layer of thick-walled
but hyaline cells (Fig. 20.4g). The fertile centre of
the peridiole is made up of thin-walled hyphae
(‘nurse hyphae’) between which basidia develop.
The basidia form 4 8 basidiospores and disappear
soon afterwards, but the spores continue to
enlarge and become thick-walled (Fig. 20.4g).
Most of the nurse hyphae also break down,
possibly providing nutrients for the enlarging
spores.