2 



THE BRITISH NATURALIST. [January 



abundant this year, as at any time since it was first turned up there 

 in 1882. This species has never yet been taken at Wicken, although 

 its food plant, Etipatorium cannahmum grows in abundance in both 

 fens. In June, as I found last year, the very pretty Bankia argentula 

 also occurs in plenty in the drier parts of Chippenham, but does not 

 seem to occur at Wicken. On the other hand Wicken has its species 

 Avhich seem to be absent from Chippenham, notably Papilio machaon, 

 w^hich is still always abundant at Wicken. Lobophom sexalisata had 

 been plentiful about the sallow bushes in Wicken Fen this year, and 

 sugar in the long lane running parallel with the fen had produced 

 Aplecta advejia in good numbers. This species was over when we 

 arrived, but its place was taken by a still better species, Agvotis ravida, 

 which although in much fewer number, with close work, all the 

 lepidopterists there managed to secure a fair series of beautiful 

 specimens. 



As most lepidopterists are aware, fen collecting is mostly done by 

 light, for which purpose a large lamp is hoisted on a stout pole, and 

 a big sheet fastened up by means of three other poles, behind it. 

 The moths are attracted by the light, and often settle either on the 

 Sflass of the lamp or on the sheet, unless they are prevented doing so 

 by the stroke of the collector's net. A sheet is not absolutely nec- 

 essary, but it is a great assistance, and moreover serves the purpose 

 of keeping off the cold wind from the collector, which wind is some- 

 times one of the greatest nuisances he has to contend with. This 

 year however " sugar" proved so attractive in the fen that it was im- 

 possible to give proper attention to the lamps at the same time, and 

 they had to be left for hours. The lamps of course attract a great 

 many species which never come to sugar, among which the big Lasio- 

 campa quevcifolia w^as a common visitor, and the male of Odonestis pota- 

 tovia varying much in quantity of dark marking, equally so. Curiously, 

 Chelonia caja w^iich on a previous visit representing the same time, was 

 so abundant as to be a nuisance, was not seen at all. The second 

 brood of its small relative Arctia fidigi?iosa was a not unfrequent visi- 

 tor, and very fine specimens they were indeed. Nudaria senex and 

 Lithosia griseola w^ere constant visitors, and an occasional var. stram- 

 ineola of the latter insect occurred. The local Nonagria hellma?ini was 

 a welcome and not uncommon species ; and late one night, to our as- 

 tonishment, a fine example of Phytometra cenea came, a species we 

 never even saw during the daytime. With them occurred a good 

 variety of Geometrae, Noctuse, Pyrales and Tortrices in greater or lesser 

 numbers. 



But it was on the " sugar " patches that most insects could always 

 be seen at one time, and some evenings the numbers were astonishing 



