POND LIFE 101
Snaresbrook. They are not so common in the Forest
district as are the species of Spirogyra.
The species of Mesocarpus, when in a barren state,
have slender threads which resemble those of Spirogyra
in a depraved condition, with the bands of chlorophyll
zigzag, but not spiral. They are not at all common in
this locality, but Mesocarpus parvulus has been found
in the Forest, whilst Mesocarpus pleurocarpus occurs at
Walthamstow. Staurospermum has threads equally
slender, but are most interesting when they have
conjugated, which they do at right angles so that the
spores are four-cornered. Staurospermum capucinum,
as well as Staurospermum gracillimum, are found in
pools and ponds at High Beach, floating on the surface,
and generally mixed with other Algae.
Simpler forms of the threadlike Algae, which are the
true Conferva;, are often found floating on the ponds,
sometimes in large masses ; especially in the case of
Cladophora flavescens and Cladophora fracta, which are
common in most of the pools at High Beach, and
elsewhere.
Of more interest are the numerous species of
OEdogonium, the life - history of which is strangely
attractive. The barren threads do not appear to differ
much from a common conferva, except that the cells are
longer and some of them present transverse parallel lines
across the cells near one extremity. The cause of this
is found in the manner of growth and development.
They should be examined when in fructification, and
then the floating tufts no longer appear green, but
brownish, and uninviting. CEdogonium vernale is
found at High Beach, OEdogonium crassiusculum on
the Loughton side, OEdogonium capillare, OEdogonium
Boscii, and OEdogonium pluviale at Walthamstow.
That singular ally, Bulbochate setigera, has been
collected at Snaresbrook, and in some of the more
northern ponds.
Two very elegant Algae are often to be found
scattered amongst other species, but never in great
quantity, which are great favourites as microscopical
objects. These are Draparnaldia glomerata, and
Draparnaldia plumosa. Not only have we found them
at Snaresbrook, but at Golding's Hill, and in other
little ponds, especially such as contain Volvox globator.
Generally speaking, the Forest is not a good locality
for the species of Oscillaria, but two species, Oscillaria
tenuis and Oscillaria tenerrima, will be met with in
ditches on the Chingford side. They are not so par-
ticular about clean water.
Protozoa. Within the past few years upwards of a hundred
species of the Protozoa have been collected and identified
from the pools of the Forest. Amongst these are some
of the simplest forms of animal life, such as the Amoeba
and species of Actinophrys, and some six or seven
species of Difflugia. More highly developed forms,
long known under the general name of Infusoria,
include many objects well known to the microscopist,