POND LIFE 103
rate nearly one hundred and fifty have been found and
recorded in the still pools of the Forest. Those in the
southern portion have been more explored than in the
north, and from Hale End, Wood Street, Snaresbrook,
and Chingford, most of the exploring expeditions have
started. Of the fixed species none are better known
than Melicerta, of which the commonest, Melicerta
ringens, has been found about Snaresbrook, Wood
Street, and Chingford. Melicerta ami/era is recorded
for Snaresbrook and Wood Street. Still more beautiful
are the species of Floscularia, of which no less than five
have been found—Floscularia ornata and Floscularia
cornuta in most of the southern ponds, Floscularia
coronetta at Snaresbrook and Chingford, Floscularia
edentata at Snaresbrook, and Floscularia campanulata at
Snaresbrook, Chingford, and Loughton. Stephanoceros
Eichhornii has also been found in nearly all the southern
waters.
Of the free-swimming species a mere list would be a
formidable one, with nine species of Anurea ; seven
species of Brachionus : ten species of Euchlanis : not
less than five of Furcularia; five of Mastigocerca ; five
of Metopidia and Notommata; four of OEcisles and
Philodina, with six of Rotifer, and five of Salpina.
In such a rich fauna it would be difficult to indicate
individual species as of special importance, although it
would appear that there are two or three species which
have not been found outside of the Forest area, such as
Calladina magna-calcarata and Pterodina caca. It is of
interest that the floating colonies of Conochilus volvox,
at one time common on Hampstead Heath, and now
almost unknown there, have been collected from Ching-
ford to Loughton.
Entomostraca. The last group of microscopical animals to
which reference can be made are the Entomostraca, or,
as vaguely termed, the water-fleas. In this group the
Forest waters are evidently strong, and especially the
waters of Wanstead Park, which latter have been
almost exhaustively explored.1 Nearly seventy species
constitute the list for the Forest district, of which sixty
have been found in the ponds of Wanstead Park, and
about forty in other localities. The old Daphnia pulex
is associated with four other species of Daphnia, four of
Ceriodaphnia, and two of Daphnella. The original
Sida crystallina, and Bosmina longirostris are still to
the fore, with five species of Alona and two of Alonella.
There are also Diaptomus castor and Diaptomus gracilis,
with Canthocamptus minutus, and no less than twelve
species of Cyclops. If we add to these four species of
Caudana and six of Cypria, with about twenty species
distributed over seventeen genera, we shall have a brief
summary of the Entomostraca of the Forest area.
1 See the Journal of the Quekett Microscopical Club for July 1893.