236
THE ESSEX NATURALIST.
having probably been blown off the trees or adhering to some
of the newer leaves of the uppermost part of the carpet. Some
Colourless members of the Eugleninae (usually classed nowadays
with the Algae) sometimes occur and will be referred to under the
Flagellates.
RHIZOPODA.
The animals belonging to this class were very much in
evidence in washings from all samples of the leaf-carpet. Of the
naked Rhizopods many forms, all species of Amoeba or very
closely allied genera, have been seen. The most commonly
occurring species has been typical A. verrucosa. Next in abund-
ance have been A. striata (sometimes regarded as an immature
form of the preceding), a small form of A. radiosa and apparently
typical A. Umax. Several small forms of the "limax" type
occurred in a good many samples, while a small form of A.
verrucosa and typical A. radiosa were each noted in a few cases.
Other species noted on one or two occasions only were A. cucumis,
A. vespertillio, A. fluida (?) and A. botryllis (?). A rather small,
but typical, A. proteus was seen only in one sample.
A great deal of work, by cultivation methods, has been done
on the Amoebae of soils in general and a number of new genera
established. It is probable that some of the foregoing records
would come under some of these, e.g., some of the "limax"
forms under Naeghria2 and Harlmanella, but by the simple
method of examination employed it was impossible to be sure of
this.
The testaceous Rhizopods were even more abundant and
very much more varied than the naked forms, being represented
by some seventeen genera and some forty species. It is to be
noted, however, that the great majority of the tests were empty.
Of the rest, a certain number contained organisms in an inert
or even encysted condition and only a small number, perhaps
some five per cent., were seen with their pseudopods extended
and in active movement. This is a point to be remembered when
comparing the relative abundance of the testaceous forms with
that of the naked forms, the records of which are necessarily all
of active individuals.
2 It has been claimed that individuals of this form can coalesce to form a plasmodium
(3). It may therefore be a stage in the life cycle of a Mycetozoan.