FUNGI AND BEECH 237
is Diatrype disciformis (Fig. 2). It is common to find fallen
twigs of beech, as thick as my thumb, with evenly-spaced
stromata of this fungus bursting through the thin bark.
Bach is circular and flat, about an eighth of an inch across,
and when examined under a lens a dozen or so perithecial
mouths can easily be seen. This is only one example; there
are many similar species.
Fig. 2. Diatrype disciformis. Portion of dead
stromata of the fungus bursting through the bark.
beech-twig showing
In a beechwood by no means all the species are growing
on wood—are lignicolous. There are many species scattered
over the forest floor, and of these only a very few have a
direct connexion with buried wood. The foraying
mycologist, collecting from the ground in a beechwood in
the early autumn, finds, if the season is a good one, a great
many species, and the majority, whilst characteristic of
woodlands, are in no way peculiar to beechwoods. How-
ever, there are just a few species which do seem to keep
fairly strictly to this habitat. Conspicuous amongst these
are Clavaria pistillaris (Plate 9), a large, unbranched,
club-shaped species, Russula lepida, Lactarius pallidus,
Coprinus picaceus, the Magpie Inkcap (Plate 10), and
Hydnum repandum, a biscuit-coloured toadstool with teeth
instead of gills below the cap. Other species are found