INSECTS 



and St. Osyth. Heferogenea limacodes (testudo) is fairly common in many oak 

 woods, but does not seem to frequent those near Harwich and St. Osyth. 

 H. asella is very local, but is widely distributed in the Epping Forest 

 district, and single examples have occurred at Colchester and Little Bent- 

 ley. The Brown-tail (Porthesia cbrysorrbaea) is a very uncertain insect. 

 It suddenly became extremely abundant for a short period about twenty- 

 five years ago, after which it entirely disappeared and was supposed to 

 be extinct ; but during the past three years it has again been found com- 

 monly near Colchester, and Mr. Mathew has also found it plentifully 

 near Harwich. The Yellow-tail (P. similis) abounds everywhere. The 

 White Satin (Leucoma salicis) is widely distributed and frequently com- 

 mon about poplars and willows, but of somewhat irregular occurrence. 

 It is probably to a large extent a migratory species, as Mr. Kerry reports 

 it coming in from the sea in thousands at Harwich on June 27, 1878. 

 The Black Arches (Psilura monacha) occurs freely in oak woods. The 

 Dark Tussock (Dasychira fascelina) was formerly common on the railway 

 embankments between Colchester and Mark's Tey, where the larvae fed 

 on broom and sallow, but since the system of firing the herbage has been 

 regularly practised it has disappeared with many other species, though 

 possibly stragglers may still linger somewhere in the district. It has also 

 occurred sparingly at Great Bentley and Southend. The Light Tussock 

 (D. pudibunda) is common throughout the county. The Scarce Vapourer 

 (Orgyia gonostigma) is found in the neighbourhood of Brentwood, where 

 Mr. Raynor says it is very local. It has also occurred at Danbury. The 

 Common Vapourer (O. antiqua) abounds everywhere, and may sometimes 

 be seen flying even in the main streets of the more populous towns. 

 The Pale Eggar (Tricbiura crateegi) is very generally distributed, but 

 seems to be nowhere common. The December Moth (Pcecilocampa 

 populi) must have received its English name from a belated specimen, 

 as it usually appears in November, when the male comes rather freely 

 to light. It is of general occurrence, but both this and the last species 

 have been scarce of late. The Small Eggar (Eriogaster lanestris] some- 

 times occurs in extreme abundance, and the webs of its gregarious 

 larva? may be seen in all directions. A few may be found almost any 

 year, but occasionally they are scarce for indefinite periods. The Lackey 

 (Eombyx neustria) is of similar habits to the last, and the same account 

 will serve equally well for it. The Coast Lackey (B. castrensis] inhabits 

 the salt marshes, from which its ova are frequently borne by the tides to 

 the higher levels of the sea walls and coast sands. Though sometimes 

 difficult to find, they are extremely abundant in favourable seasons such 

 as 1899 and 1900 and occur in suitable places all along the coast from 

 Southend to Harwich. The Fox Moth (B. rubi) is often abundant on 

 the coast and elsewhere in the larva state in the late autumn, and the 

 perfect insect may sometimes be seen flying over rough uncultivated 

 places in June. The Oak Eggar (B. quercus) is generally common, but 

 there are often periods of scarcity during which its larvae may be looked 

 for to very little purpose. The Drinker (Odonestis potatoria) was ex- 



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