184
THE ESSEX FIELD CLUB.
" Although these small rivers play this part of distributors, we may well
enquire whether they do not act sometimes as barriers against certain
species—whether, for example, the river Chelmer, running here from west to
east, is not a barrier against (sa)) the little Climbing Corydalis (C. claviculata),
which we found at Baddow, but which, so far as I know, is not reported north
of the Chelmer river. Whether that be so or not, the rising ground between the
two valleys (that is, the watershed) is sometimes a barrier to both animals and
plants ; for we could name species of each occurring in the river Stort which do not
occur in the Chelmer.
" Our walk next took us to the ancient course of the Chelmer river, now
pretty, much a disused channel, owing to the construction of the canal a little
further south. Alongside this ancient serpentine channel, a straight cut of about
the same width occurs, which is an artificial course, perhaps made for flood-
water."
The following interesting plants were noticed by Mr. Nicholson :—Carda-
mine annua, in a wet spot in a small wood ; Ruscus aculcatus and Adoxa
moschatellina, amongst bushes ; Corydalis claviculata, in plenty along a woodland
path ; Orchis morio, in marshy common ground ; Convallaria majalis, a fair-
sized patch in a wood, but no flowers visible ; Rhamnus frangula and Euony-
mus euro panis, both in flower. The magnificent show of Broom, all in full
blossom, was much admired, as also was a small rockery at the "Old Rodney,"
which was very gay with Aubrietia, Alyssum, Saxifraga stansfieldi, Arabis, a
rose-coloured Oxalis, and an alpine Phlox having a flower almost exactly like
that of the Oxalis,
Mr. Enock, who acted as the entomologist of the party, reports that the
district traversed appeared likely, if carefully searched, to afford many interesting
results ; but the rapid ramble did not allow of any systematic collecting. He
"swept" in several places, and obtained swarms of Diptera, among which were
several specimens of the "Snout-fly" (Rhingia rostrata), many species of
Empis, Dolichopus, Syrphus, etc., and several Coleoptera and Ticks (Ixodes).
Neuroptera were represented by "Scorpion-flies" (Panorpa) and "Lace-wing
Flies" (Hemerobius). With these were countless species of Parasitic Hymen-
optera, many gorgeous in colours of green and gold, for which students are
looked for in vain. The net also contained great numbers of tiny "spiderlings,"
which, just at this time, were emerging from the eggs. Mr. Enock identified the
following:—Anoplus, Cosmocoma, Gonatocerus, many specimens of each.
Several common Lepidoptera were noticed—the lovely Orange-tip butterfly
plentifully, one specimen of Euchelia jacobeae, and the exquisite little Moth the
"Speckled Yellow" (Venilia maculata) amongst others. In an oak coppice,
a tree was observed bearing some fine specimens of the Currant Gall (Spathe-
gaster baccatum) and of the "Oak Apple" Gall (Teras terminalis).
Lunch was taken at the "Old Rodney," at one o'clock, after which the
ramble was resumed, a sharp storm delaying the party for about half-an-hour.
To continue Mr. French's report :—"After crossing the Chelmer navigation,
we soon came to the rising ground, the rise being continuous until Baddow
Rodney, some two or three miles distant, was reached. We there attained to
an elevation of about 300 feet above the valley. We had, in fact, climbed to the
summit of a ridge extending to a slightly greater elevation a little further south-
west. Geologically speaking, we had now reached a very interesting spot.
Around the flanks and base of this ridge, the Boulder Clay has been wrapped