172 THE ENTOMOLOGIST. 
to occur sometimes in abundance, but of late years it seems to have 
become very rare; last season, only one specimen being noticed so 
far as I can ascertain from those who visited the fen. In June and 
July the larvee of various Leucanide may be found at night on the 
reeds (Phragmites communis) ; those of L. pudorina not being un- 
common. The perfect insects of this genus. are sometimes in great 
abundance, flying over the herbage after dusk later in the season. 
Tn the stems of the reeds the larve of Macrogaster arundinis feed 
with those of Leucania phragmitidis and Chilo phragmitellus. A 
good way of collecting the imagines of these species is to examine 
the freshly-cut reed and sedge stalks at night with a lantern. 
They are then often found just after emerging from the pupa- 
cases. ‘his applies to other species, such as the scarce and 
variable Senta ulve, although at another period of summer. 
Callimorpha dominula is another curious case of an abundant 
insect becoming rare in this locality. A few years ago it was 
common at Wicken; the larve could be found in spring feeding 
upon almost every species of plant growing there, but apparently 
most preferring the meadow-sweet. It is now no longer common ; 
in fact, in some seasons, being quite scarce. In June the larvee of 
Chelonia caja abound upon the comfrey; a large number may be 
taken on a single sunny morning. On the bedstraw (Galiwm) 
Cherocampa elpenor may be found also as a larva, while upon the 
sedge, Simyra venosa is frequently in numbers. Sesia bembe- 
ciformis may be found boring the sallow stems, and the great fat 
larve of Lasiocampa quercifolia stick closely under blackthorn 
stems by day. Saturnia carpimt are common on meadow-sweet 
and sallow in early autumn. All the larvee mentioned should be 
collected, if possible, for many fine varieties have been bred from 
the fen-lands. 
During the last few seasons the chief mode of collecting 
Lepidoptera in the fens has been with light. This has been 
found by far the most successful means used for making large 
“bags” of rare and local species which could not be allured by 
the charms of ‘‘ sugar,” or indeed any other bait. The way to 
proceed is to get a “ lighthouse,’ which may be obtained at one 
of the shops where we buy our other entomological apparatus. It 
consists of a glass case some two feet square affixed on a 
pole about six feet high. In this glass case are placed two or four 
paraffin lamps, as large as can be conveniently managed. These 
