﻿GAS-LAMP ENTOMOLOGY. 63 



Cidaria, and the " Thorns " are especially conspicuous. Arctia 

 caia, Spilosoma lubricipeda, and S. menthastri are always certain 

 to come in their season by the dozen. I helped an A. caia one 

 night no less than three times out of my net, and over the hedge, 

 until it returned a fourth time and fell a victim to a bat. 

 A. fidiginosa I never even saw. Hepialns hamuli rarely allows 

 itself to be trapped, although dancing over the grass by the 

 dozen ; and H. lupulinus never, though equally common. 



The best nights for lamp -hunting are those that are warm, 

 dark, and still. Insects are very sensitive to temperature, 

 therefore a thermometer below 50° F., marks a paucity of sport. 

 Few moths, if any, will be abroad in moon or starlight. A strong 

 wind is equally unfavourable. If the weather-vane points at all 

 to the east, the entomologist may certainly rest indoors, 



I have always observed two chief flights of moths in a night. 

 With the dusk appear the Geometers; these are afterwards 

 followed by the Noctuas; and this flight goes on till eight 

 o'clock. After an apparent rest of a couple of hours, the second 

 flight begins at ten, with diminished Geometers but increased 

 Noctuas, and continues till midnight. The entomologist may 

 then turn in and empty his cyanide bottle. He should have in 

 readiness a large wide-mouthed pickle bottle, half-filled with 

 chopped and bruised laurel leaves. On the top of the leaves, 

 which should be well pressed down, a piece of perforated card 

 should be placed, and fitting the bottle. On this the insects may 

 be laid, when they will remain perfectly natural and relaxed for 

 a week or more. Moths of a green colour, like the Emeralds, 

 should be set at once ; in fact, they should be removed from the 

 cyanide bottle as soon as killed, pinned into a pocket-box, and 

 set on reaching home. This is the secret in preserving the 

 exquisite tint of an insect like Geometra papilionaria. 



The entomologist at the top of his ladder on a favourable 

 night looks into a veritable insect world. Thousands of gnats, 

 many in their last struggles for existence, cover the bottom 

 of the lamp. These gnats, when seen on the wing at the 

 approach of dusk, are sure harbingers of successful sport. If it 

 be the month of August, half a dozen Noctuas may be inside, 

 sullen and quiet. A beetle or two, with numerous earwigs and 

 three or four Geometers, swell the company. Some of the 

 lepidopterous insects are scorched by the flame, but the greater 

 proportion are fit for the cabinet. The whitish eggs on the glass 

 inside are probably those of Luperina cespitis. Outside there will 

 be more earwigs, a G. papilionaria if birches are in the neigh- 

 bourhood, Noctuas, more Geometers ; and all these, as a rule, 

 will be as fresh as if straight from the chrysalis. Spiders are 

 feasting busily on the dying gnats, and a bat flies up and down 

 and about, taking, the meanwhile, a liberal tithe. The great pest 



