202 MOLLUSCA OCCURRING IN BISHOP'S STORTFORD.
highest ground in the district between Greenwich and Dartford,
which certainly lies in a slight synclinal basin, the Blackheath Pebble
Beds at Woolwich dipping slightly under Shooters' Hill and coming
up again southward of it at Eltham. It seems, therefore, probable
that the Bagshot outliers of Warley, Stock and Billericay, with the
heights of Danbury and Tiptree Heath, may owe their preservation
in a considerable degree to their position on a long line of synclinal
fold.
MOLLUSCA OCCURRING IN THE NEIGHBOUR-
HOOD OF BISHOP'S STORTFORD.
ADDITIONS AND CORRECTIONS.
By EDWIN G. INGOLD.
SINCE my paper on the above was published in the Essex Natu-
ralist (vol. iv., pp. 215-217), I have been able to add two
species to the list of local Mollusca; and I find it necessary to make
corrections in the determination of some species in my collection,
at the instance of the referee to the Conchological Society.
The additions to the previous list are :—
Ancylus lacustris, L. River Stort; uncommon.
Helix hortensis, Mull. Hedgerows; common.
The corrections necessary to be made are :—
For Paludina contecta read P. vivipera, L.
Delete Zonites alliarius and Z. excavatus (the supposed specimens
of the former were a variety of Z. cellarius, and the latter a variety of
Helix hispida).
For Helix concinna read Helix hispida, L.
For Pupa umbilicata read Pupa marginata, Drap.
All the remaining species in my list are, I believe, correctly
named, and I regret that any mistakes should have occurred.
NOTES—ORIGINAL AND SELECTED.
Late nesting of Rooks at Felstead.—Mr, J. French, writing on October
28th, said :—"Some Rooks of about five or six weeks old have been observed
since October 20th in this village (Felstead). Nothing is known of their nest, or
whether they are first or second broods. It is believed to be an uncommon