2
SOME BIOLOGICAL PROBLEMS AS
ILLUSTRATED BY THE ENTOMOSTRACA.1
(Being a Presidential Address delivered to the Club on 29th March,
1930.)
By D. J. SCOURFIELD, I.S.O., F.L.S., F.Z.S., F.R.M.S.
(With Two Text Figures.)
WHEN I first came into touch with the Essex Field Club
I had already made a good many collections of the little
Crustaceans, commonly known as Entomostraca, from the ponds,
etc., of Epping Forest. Mr. William Cole, who was then in the
heyday of his activities as secretary and editor, scenting, I
suppose, as secretaries and editors so mysteriously seem to do,
a possible communication for a meeting of the Club, with
subsequent publication in the Essex Naturalist, urged me
very persuasively to put together my notes about the species
I had found in the Forest area and, as the group had not been
dealt with before by anyone in the Club, to incorporate in the
paper some general remarks about these small aquatic animals.
This I eventually agreed to do, and the result was a paper
entitled "The Entomostraca of Epping Forest, with some
general remarks on the Group," which was published in the
Essex Naturalist in 1898.2 I am very pleased to acknowledge
that it was Mr. Cole's persistent encouragement which made
me prepare that paper, at least at that time, and so put me quite
definitely on the path that I have followed more or less con-
sistently ever since.
In the introductory part of the paper referred to it was
pointed out that by no means all the varied problems connected
with the Entomostraca were dealt with in the general remarks.
It has seemed to me, therefore, that we might now usefully
consider some of those further problems which were then omitted
and at the same time perhaps give a little more attention to
one or two of the subjects previously touched upon. In so
doing it will, I think, be preferable on this occasion to look at
the matter the other way round, so to speak, i.e., instead of
1 This term, although no longer recognised as representing a natural group of the Crustacea
is here used as a very convenient one to cover the sub-classes Branchiopoda (more particularly
the order Cladocera), Ostracoda and Copepoda.
2 Essex Naturalist, vol. X., pp. 193-210, 259-274 and 313-334.