Collecting Lepidoptera in the Eastern Counties

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COLLECTING LEPIDOPTERA IN THE EASTERN COUNTIES ; SOME REMINISCENCES.

BY BARON DE WORMS, M.A., PH.D., F.R.E.S.

THE Eastern Counties of which Norfolk and Suffolk form the recognised centre, seem to have a peculiar attraction for the entomologist and in particular for the collector of lepidoptera. Few parts of the British Isles possess such a richness of marsh and mere, while the unique Breckland provides a special hunting ground for many prizes.

The adjoining counties of Essex and Cambridgeshire have just claims to be included in the area under review and as for my own experiences, these can be said to have started just thirty years ago, in 1922, in that famous locality, Wicken Fen. Those were the days when throughout the summer season the main drive used to be illuminated night after night with a row of upright sheets and acetylene burners, while eager collectors carried out frequent rounds of the sugaring posts which were often alive with choice fen species. A good night in Wicken was a sight to see about midsummer with the sheets buzzing with such specialities as Phragmatoecia casteneae, H端bn., our only reed Cossid, and that choice member of the Dagger family, Simyra albovenosa, Goeze, but the great prize in those days was the elusive little Hydrillula palustris, H端bn., usually known as the Marsh Moth. The first I saw of it was on June 12th, 1926, when on a very damp and chilly night, about 2 a.m., a very insignificant looking little moth suddenly appeared on my friend's sheet, a perfect male specimen, but it was not tili 1929 that I was able to emulate his capture. Well do I remember too, being roused from my slumbers by hilarious shouts in the small hours of a June night in 1932.

Two friends had caught two examples of this insect on the edge of the Breckland, just inside the Suffolk border, quite an unexpected locality which has never produced it since. This insect was taken in most years at Wicken up to 1939, since when it has been regularly sought in another fen locality where larvae were found by Mr. H. M. Edelsten and the late Sir John Fryer and its life history eventually worked out. Before the war, I visited Wicken annually, but have only been there twice since then. Gone are the sheets and most of the sugaring posts as well as the constant stream of nocturnal collectors, but the venerable keeper, Mr. George Barnes, is still on the active list after over 30 years in the Fen. The neighbouring fen at Chippenham is a good rival to Wicken. The Rev. Guy Ford and I had a grand battue there in 1948 with heaps of the Reed Leopard (P. castaneae, H端bn.), and the little Silver Hook (Banksia argentula, H端bn. = olivana, Schiff.) to beflushedat every step.

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COLLECTING LEPIDOPTERA IN THE EASTERN COUNTIES

The Breckland is the next port of call in this Odyssey round the Eastern Counties. In the old days before the war, amongst the waste ground along the Mildenhall line at West Row could be found in plenty, those two small specialities of the area, Sterrha rubiginata, Hufn., and Emmelia trabealis, Scop., while nearby a noted spot for the pretty geometer Euphyia cucullata, Hufn.

It was said that the local parson used to reserve afieldwhere these speciesflourished,specialy for the use of his Bishop, the late Dr. Whittingham. On returning to these surroundings recently, I was horrified tofindthem all under plough and part of them an aerodrome. This has been the fate of so much of this attractive countryside. Eriswell used to be the centre of that fine noctuid Anepia irregularis, Hufn. Here its special foodplant, Silene otit used to be in abundance. I can well recall a very warm night in June, 1938. A friend and I were in the process of catching this species which was Aying in numbers at dusk when a raucous voice enquired our activities. The local keeper imagined we were poachers. However, a few diplomatic words reassured him we were bonafidecollectors, but the interlude prevented us making the most of theflightand we never saw another of this moth. In the late Thirties we paid several visits to the Brandon area which appeared to be the headquarters of that very pretty little insect, known as the Grey Carpet (Lithostege griseata, Schif Here, in rather aridfields,it could be readily disturbed about mid-June from the ground where it rested simulating the small white stones. I was very glad tofindit still in this district in 1951 while in Company with our late Secretary and Mr. P. J. Burton.

Sugaring, too, in the Breck was always quite an exciting pastime.

Since its boundary was supposed to be an old coast line, many normally maritime species were to be found there, such as Heliophobus albicolon, HĂźbn., and Actebia praecox, Linn railway posts at West Row were the scene and source of many of our harvests of these noctuid moths. Nearby on the outskirts of Bury St. Edmunds was one of the few localities for the Barberry Carpet (Coenotephria beroerata, Schiff.), but owing to the continual eradication of its foodplant which is the host of a virus disease in cereals, the foothold of this species is very slender in this country.

The next area under review is the Norfolk Broads, that mecca of entomologists and many others in all walks of life. My first recollections of them were on a boating trip in June, 1926, when I had the opportunity of seeing the Swallow-tail (Papilio machaon, Linn.), in large numbers for thefirsttime, but it was not tili August, 1932, that I had myfirstintensive collecting on the Broads.' Horning and Barton Broad were the chief hunting grounds. The former locality harboured that much-sought-species Fenn's Wainscot (Arenostola brevilinea, Fenn.). Here it was to be found plentifully Aying at dusk among the reed beds, while the nearby sugar patches produced a host of the commoner marsh species including another local speciality, the Dotted Footman

C0LLECT1NG LEPIDOPTERA IN THE EASTERN COUNTIES

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(Pelosia muscerda, Hufn.). This species was also common on Barton Broad where our main quest was the Reed Wainscot (Nonagria algae, Esp. = cannae, Ochs.). The chief modus operandi was to get rowed round the beds of scirpus and typha on the edge of the Broad with the hope of being able to spot those stems which were infected by a larva or pupa, whichthenrequired excavation or cutting the stem off well below and above the exit hole. In 1933 on one of such expeditions our boat got nearly swamped in a thunderstorm. In 1937 a party of us had quite a harvest in this area, both with the species already mentioned and also of the Little Footman, Eilema pygmaeola, Doubl., on the sandhils near Horsey gap, its only known locality outside Kent.

The last time I visited the Broads was in August, 1939, when the clouds of war were already hanging heavy over us. On this occasion, Nonagria cannae, Ochs., came in great plenty to my lamp in a boat skilfully manoeuvred through the swamp by Mr. Gane, vvho was a regulär summer visitor to this area. The coastal regions of Norfolk where there are sandhils are particularly rieh for the summer noctuids such as Agrolis ripae, Hübn., in June, Arenostola elymi, Treits., in July, the pale form of Euxoa cursoria, Hufn., in August, while in early September on the northernmost fringe I had great success in the late Thirties finding the slender larvae of the very local Scarce Pug (Eupithecia extensaria, Frey.), feeding on the sea wormwood.

As for Suffolk, apart from collecting on the fringe of county in the Breck, myfirstreal introduetion was in 1938 when I made quite a pilgrimage in search of the Frosted Yellow (Isturgia limbaria, Fabr.), in the Stowmarket and Ipswich districts where it once flourished. The late Mr. Platten kindly gave me a lot of helpful information on when he used to take it, but in vain did I seek it and I doubt if it has been Seen later than 1912. Since the war, thanks to the good offices of Mr. P. J. Burton, I have made almost annual trips mainly to the Lowestoft area which has proved very produetive. It was in April, 1946, that I had the satisfaction of seeing the Large Tortoiseshell (Nymphalis polychloros, Linn.), quite numerous,flittingabout the local gardens and sailing up and down rides in the woods. Later in July of that year we found several live pupae under the eaves of farm buildings. Düring my April visit near Fritton small larvae of the White Admiral (Limenitis Camilla, Linn.), were to be found on almost every piece of straggling honeysuckle, but have not been seen there in such numbers since. The form of the Silver-studded Blue (Plebeius argus, Linn.), found on some of the heathlands in East Suffolk, is of special interest owing to its large size and the tendency of the females to blueness. I have had several opportunities of studying them. They seem to be quite distinet from the heath form prevalent in the southern counties. Sandhil and saltmarsh collecting along the Suffolk coast canbemostexciting and profitable.

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C O L L E C T I N G LEPIDOPTERA IN THE EASTERN COUNTIES

I well remember a remarkable night in July, 1946, when the marrams were alive with good moths, notably the Lyme grass (A. elymi, Treits.), and the Crescent-striped (Apamea oblonga, Haw. = abjecta, H端bn.), while two years later the Sand dart (Agrotis ripae, H端bn.), was swarming on the grass heads. It was on this occasion that I took the only local record of Arenostola hellmanni, Ev. = fluxa, H端bn.

Several autumn visits to this coast have been quite productive, especially in search of the dark forms of the Feathered brindle (Aporophyla australis, Boisd.), which are often quite prevalent near the sandhills. It was in September, 1949, that I was about to sugar a post near Sizewell Gap when a large lump on it proved to be a Convolvulus hawk (Herse convolvuli, Linn.), but our Operations here were interrupted by a posse of the local constabulary who maintained we were misleading the shipping with our lamps. In a further visit in July, 1950, Mr. Burton and I concentrated on the large expanses of marshland where we were glad to rediscover Nonagria neurica, H端bn., known as the Sussex Wainscot, since it was originally only known from one locality in that county. The late Sir John Fryer was the first to find larvae in Suffolk as far back as 1924.

In the ensuing twenty-five years, an occasional specimen was bred out, but its true headquarters were not known tili quite recently.

Another surprise capture in this area was Arenostola breviliena, Fenn., which had only once been recorded for Suffolk and then only in the northernmost corner of the county. Most of the large coastal marshlands have hardly been worked entomologically and they may yield many more secrets, especially in the Orford and Aldeburgh areas.

The latter locality is notable as being the only area outside the east coast of Kent where the Ochraceous wave (Sterrha ochrata, Scop.), is to be found commonly. In 1937 and again in 1938 when I was on this ground the Pine Hawk (Hyloicus pinastri, Linn.), was in numbers on the pine trunks. It is now widespread over most of Suffolk and a large portion of Norfolk.

Essex is the last county to come into our orbit, but it is one which has never greatly attracted my attention, though it is very rieh for lepidoptera. Its southernmost and eastern shores harbour the Essex Emerald (Euchloris smaragdaria, Fabr.), almost its only known habitat, while the saltings in July often abound with larvae of the Ground lackey (Malacosoma castrensis, Linn.). It was in 1934, near Colchester, that I had my earliest captures of Matthew's Wainscot (Leucania favicolor, Barr.), which was originally described from this area, but which is now known to occur in several places along our south coast.

I have endeavoured in this survey and reminiscences to give some idea of the possibilities of collecting in our Eastern Counties and of the many local species, some of which are peculiar to the region, which, indeed, is one of the most attractive in our Islands and is well worth a visit and further research into its flora and fauna.