List of the Insect Fauna of the County. 153
N. fumipennis, Hart. Gall on Quercus. Common.
N. tricolor, Hart. Gall on Quercus. Rayleigh.
N. laeviusculus, Schenck. Gall on Quercus. Maldon,
 Rayleigh.
N. albipes, Schenck. Gall on Quercus. Maldon.
N. numismatis, Oliv. Gall on Quercus. Very common.
N. vesicatrix, Schlecht. Gall on Quercus. Maldon.
Hymenoptera. Tenthredinidae.
Nematus, Jurine.
N. gallicola, Westw. (Vallisnierii, Hart.). Gall on Salix.
Very common.
N. Viminalis, L. (pedunculi, Hart.). Gall on Salix. Gene-
rally distributed, but not common.
Cryptocampus, Hartig.
C. pentandrae, Retz. (medullarius, Hart.). Gall on Salix.
Maldon.
Lepidoptera. Tineidae.
Laverna, Curtis.
L. decorella, Steph. Gall on Epilobium. Generally distri-
buted, but not common.
Diptera. Cecidomyidae.
Cecidomyia, Meigen.
C. bursaria, Bremi. Gall on Glechoma. Birdbrook, Widford.
C. ? clausilia, Bremi. Gall on Salix. Maldon.
C. Crataegi, Wtz. Gall on Crataegus. Very common.
C. Galii, H. Loew. Gall on Galium. Birdbrook, Maldon,
Rayleigh.
C. foliorum, H. Loew. Gall on Artemisia. Grays (W. F.
Gwinnell). See 'Proc. Essex Field Club,' ii., pp. xvi., xx.
C. Persicariae, L. Gall on Polygonum. Burnham, Canewdon,
Cricksea, Maldon; Canvey, Foulness and Wallasea
Islands.
C. plicatrix, H. Loew. Gall on Rubus. Maldon.
C.? Pruni, Kalt. Gall on Prunus. Maldon.
T