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THE ESSEX NATURALIST.
A few forms, especially our common shore-inhabiting Anurida,
are carnivorous and feed on decaying molluscs. Species of
Collembola are to be found almost anywhere, amongst herbage
by sweeping, under stones, under the loose bark of fallen logs,
on the surface of pools, in dry woodwork of houses and under
stones between high and low tide mark on our sea shores.
Collecting is a comparatively easy matter, all that is required
(beyond a lot of perseverance) being a few small tubes of spirit
and a fine brush. With practice specimens may be picked up
on the brush damped with spirit and then transferred to a tube.
Except for microscopical mounting they are best kept in the
spirit.
The best medium for mounting is by far a gum and chloral
hydrate mixture, although for a preliminary examination of
details 10% caustic potash is suitable. From the spirit or
potash for permanent mounts they must be passed through
glacial acetic acid before placing in a drop of gum-chloral on the
slide.
Little literature is available in English on the Collembola,
other than Lubbock's "Monograph on the Collembola and
Thysanura," which is now quite out of date. Much detail can,
however, be got from "The Apterygota of Hertfordshire" by
Collinge and Shoebotham in the J. Econ. Biol. 1910, vol. v.,
while in my "Collembola of Ireland," Proc. Roy. Irish Acad. 39,
B, II., 1930, I give tables for the determination of all British
species known to date.
LIST OF THE COLLEMBOLA OF EPPING FOREST.
Sub-order: Arthropleona Borner.
Family: Poduridae Lubb.
Sub-family: Podurinae Borner.
Podura aquatica Linn. This species has been taken abundantly
by Mr. Scourfield on the surface of ponds.
Sub-family: Achorutinae Borner.
Pseudachorutes asigillatus Borner. A few under loose bark.
Achorutes muscorum Tempi. A few under loose bark.
Sub-family: Onychiurinae Borner.
Onychiurus armatus Nic. A white species, without furca, with
strong anal horns. Common in the leaf-carpet.
Onychiurus ambulans Linn. A very closely related species.
Found under bark.