156 The Galls of Essex.
Pemphigus, Hartig.
P. bursarius, Hart. Gall on Populus. Generally distributed,
but not common.
P. spirothecae, Koch. Gall on Populus. Heybridge, Maldon,
Rayleigh.
Tetraneura, Hartig.
T. Ulmi, DeGeer. Gall on Ulmus. Generally distributed,
but not common.
Adelges, Vallot.
A. Abietis, L. Gall on Abies. Common.
[The whole of the cuts of Oak-galls illustrating this
paper were kindly lent by Messrs. West, Newman & Co.
The Editor is indebted to Miss Ormerod for the cuts of
Cecidomyia Ranunculi and Ceuthorhynchus sulcicollis. The
remaining blocks were engraved expressly for this paper.
—Ed.]