THE ENTOMOSTRACA OF EPPING FOREST. 209
the "best books" will probably be useful, therefore, to any who
may be induced to take special interest in this subject.
From the point of view of general structure, affinities, and
main divisions, very good articles on the Entomostraca may be
found in many text-books of Zoology, but special mention may
be made of Huxley's Anatomy of Invertebrated Animals, Claus's
Text-book of Zoology, and of Gerstacker's comprehensive account
in Volume V. of Bronn's Klassen und Ordnungen des Thierreiclis.
An article by J. Vosseler (106) in Zacharias's Thier and
Pfianzenwelt des Siisswassers contains a short but very good general
account of the group, and similar articles of a more or less
general nature also occur in most works dealing with the
microscope and microscopic objects, such as Griffith and
Henfrey's Micrographic Dictionary, Carpenter's Microscope and its
Revelations, &c. The facts known as to the embryology of these
animals is well summarised in Balfour's Comparative Embryology,
and more recently in Korschelt and Heider's Lehrbuch der
vergleichenden Entwicklungsgeschichte der wirbellosen Thiere (2. Heft,
1892), a translation of which is now in the press.
Of the special works devoted to the Entomostraca, the
starting point for English workers is still Baird's Natural History
of the British Entomostraca (2), published by the Ray Society in
1850. Much of the ground covered by this classical treatise has
since been re-monographed, but not so exhaustively as to render
the older work quite obsolete. In fact for the Phyllopoda,
Branchiura and parasitic Copepoda we have nothing in addition
to Baird's work, and for the Cladocera we only possess two
subsequent papers of importance, namely, Norman and Brady's
Monograph of the British Entomostraca (56), which is confined
to the families Bosminidae, Macrothricidae and Lynceidae, and
Brady's British Species of Entomostraca belonging to Daphnia,
&c. (20). For the Ostracoda we have two fine monographs,
the first, A Monograph of recent British Ostracoda (10), by G. S.
Brady, and the other, A Monograph of the Marine and Fresh-water
Ostracoda of the North Atlantic and of North Western Europe (21),
by Brady and Norman. The British Copepods have been very
fully treated by Prof. Brady in A Monograph of the Free and Semi-
parasitic Copepoda of the British Islands (16), and the fresh-water
forms belonging to the Cyclopidae and Calanidae have more
recently been revised by the same author in A Revision of the
British species of Fresh-water Cyclopidae and Calanidae (19). The
above are the standard works of reference on the British Fresh-