surface of the water, though some species construct a portable case of leaf-
fragments which is allowed to float. The adults are mainly nocturnal and come
to light. All four of the resident species occur in Essex. Recently, however,
eight foreign species, mainly from the far east, have been found breeding in
aquatic nurseries, mostly in Hertfordshire near the Essex border. They cannot
survive in the open, but anyone who purchases these plants for his aquarium is
quite likely to get some of the larvae into the bargain.
Nymphula nympheata (Linn.) Res., (1834)-1980. Potamogeton and other aquatic plants. Wdspd
and c.; under-recorded in north Essex. 40 *Epping by Doubleday (Stephens, 1834:39).
Parapoynx stratiotata (Linn.) Res., 1867-1978. Potamogeton and other aquatic plants. Wdspd and
f.c. 02 *Colchester (Harwood, 1867-1868).
P. stagnata (Don.) Res., (1886)-1979. Sparganium, Nuphar lutea. Loc. and rather r.
VC 18.38 Leyton; 48 Wanstead (AT); 68 Bulphan; 89 Stambridge (HCH); 90 Bradwell-on-Sea
(AJD). VC 19. 41 Sawbridgeworth Marsh NR (G.H.B.Sell); 80 Ulting (HCH); 82 Bradwell
(AME); 83 Henney (WSG and GH in coll. Wakely); 02 *Colchester (Leech, 1886; coll.
Purdey).
Cataclysta lemnata (Linn.) Res., (1834)4979. Lemna spp. Wdspd and loc. c, especially in the
south. 40 *Epping by Doubleday (Stephens, 1834: 40).
Evergestinae
Large to very large moths with broad, triangular forewings which are
ochreous or yellow with darker markings. The larvae feed on Cruciferae,
sometimes gregariously; E. forficalis is sometimes a pest in market gardens.
The adults fly at night and come to light. All three British species occur in
Essex.
Evergestis forficalis (Linn.) Res., (1834)-1980. Cruciferae. Wdspd and v.c. 40 *Epping by
Doubleday (Stephens, 1834:46).
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