16
THE MYCETOZOA :
were also abundant on the fallen boughs lying amongst the
wet grass beneath. In Epping Forest, we have repeatedly
found Colloderma oculatum on living trunks of old pollard oaks,
especially where a trickle of water from the crown of the tree
kept a crevice of bark moist for weeks together ; here crop
after crop of sporangia has appeared. In Epping Forest,
too, Enerthenema has been found amongst moss on living
oaks.
On decaying oak wood, amongst the many Mycetozoa that
thrive, may be mentioned Badhamia capsulifera, B. nitens, and
Diderma floriforme, whose sporangia open like flowers with
petal-like lobes.
On heaps of Spent Tan, where broken up oak bark is satur-
ated with animal matter from tanning hides, the bright yellow
aethalia of Fuligo septica blossom forth so suddenly and so fre-
quently that they have received the popular name of " Flowers of
Tan." Beside this showy and extremely common species, careful
search may also detect in such a habitat the minute yellow
sporangia of Cornuvia serpula, only known from tan heaps, and
probably considered rare because we do not frequent tan-yards
enough. The only British gathering of Cornuvia was made
by Mr. M, J. Coon, who found it in some abundance near St.
Austell, in Cornwall, on tan, from which he also obtained
Oligonema nitens.
Half-submerged Logs.—A special habitat is to be found
in logs of oak and birch (and probably of other trees) lying on
the marshy borders of woodland pools. These logs, which are
liable to partial submergence in wet weather, afford a
characteristic haunt, at least in England, for the two species
of Oligonema, O. nitens and O. flavidum. It is a welcome ex-
perience, on turning over some dead bough lying on black soil
which was once the bottom of a pond, to have the shining clusters
of these minute sporangia meet one's gaze. Trichia persimilis.
a common species elsewhere, is also often found on half-sub-
merged wood.
Hornbeam logs are favourable for the growth of many abund-
ant species, such as Stemonitis fusca, Enteridium olivaceum,
several species of Trichia, Perichaena populina and P. depressa.
On mossy trunks of both living and felled hornbeams, Colloderma
oculatum has repeatedly been obtained in Epping Forest,