NOTES ON COLLECTING, ETC. 
89 
intervals shining brightly on the sugared trees, and the insects appar- 
ently enjoying it. 1 think, however, the moon affects light collecting, 
as it diminishes the power of the lamp so much. The reason the 
moon gets so much abuse is simply this. When it is a cold, clear 
night and there is a moon, you always see it ; in fact, you don’t see 
much else except the moon and its shadows. When it is a warm night 
you don’t very often see the moon if there is one, as it is usually 
cloudy. I daresay few collectors will agree with me, but this is at 
present my theory, and it will be interesting to hear what more ex- 
perienced collectors have to say. — A. Robinson, i. Mitre Court 
Buildings, Temple, E.C. May, 1891. 
Uncertain appearance of certain Lepidoptera. — With regard to 
Mr. Holland’s remarks on MelitcBa aiirinia (vol. ii., p. 67), it is a most 
variable insect in its appearance here. There is one particular field, 
where it sometimes swarms ; this was the case in 1888, in 1889 only a 
few were to be found, and last year not one. But I believe it will turn 
up again, as the same thing has happened before. — K. C. Dobree Fox. 
April, 1891. 
I could write pages on the disappearance of insects which were 
common in my early collecting days in localities from which they have 
long departed, but it is a wide subject and will bear no hasty generali- 
sation. The vagaries of species like Aporia cratcegi, Lyccena ads, 
Endromis versicolor, A lends pictaria, Moma orio?i, Ctispidia alni, 
Efmomos aiitiinmaria, Eupitlieda dodoneata, Argyrolepia schreibersiana, 
Papilio machaon, Epimda nigra, E. luiulenta, Dicyda 00, etc., would 
fill a good sized volume. Near all large towns the ever increasing smoke 
must have a great effect, and this is remarkable in the London district, 
but there are other causes, of which we have at present but a faint 
idea. — C. Fenn, Lee. April, 1891. 
As to the disappearance of species from a locality, I can give but one 
instance. In the summer of 1888, Frocris statices was extremely 
abundant in a meadow at Enborne (Newbury). For two or three days 
the place seemed alive with them, and it was curious to remark that all 
the moths seemed flying in one direction, although there was no wind 
whatever. In 1889, I visited the same locality constantly, hoping to 
get more P. statices, but I only saw one specimen, and last year I saw 
none at all. I have worked for the species in the fields lying to the 
S.W. of their former habitat, as the general flight of the insects was in 
that direction in 1888, but have failed hitherto to discover them in any 
fresh spot. It will be interesting to find if, in the coming season, they 
reappear in their former locality, or in another in the same district. — 
M. Kimber, Cope Hall, Newbury. April, 1891. 
Twenty years ago Plusia festucce was to be had in almost unlimited 
numbers in the larval and pupal stages in the Warrington district. I 
have heard my father speak of breeding hundreds in a season from pupae 
obtained here. I have myself seen evidence of their former abundance, 
a deplorable ring of closely packed P. festucce in a wall-case, bodiless, 
and wholly given up to mites. Now we seldom take more than half-a- 
dozen imagines a year; the only pupae got of late were five in 1889. 
Formerly their particular locality was a tortuous, winding, slow-flowing 
brook or rivulet, with Carex growing in luxuriant masses from its sides. 
Such, I am told, was the paradise where P. festucce revelled in numbers. 
