OCCASIONAL ABUNDANCE OF INSECTS. Al 
Octobers and suggest that such wetness was fatal to the | 
larve, because although they lived long enough to be 
noticeable, they died completely enough to prevent any 
survivals to the next year. 
Again considering the season 1888. It might be asked, 
if the prevailing cause of the annual destruction which 
decimates the larve of this moth be our usually wet 
autumns, why the abundance was not carried over to the 
next year 1889, as the whole of the autumn of 1888 was 
unusually dry. To such an objection, I would reply that 
although I believe much rain to be a prevailing I do not . 
maintain that it is the only cause. I explain the abun- 
dance of the almost mature larve during that autumn by 
its unusual dryness and I think that some other detri- 
mental agency must on that occasion have taken the place 
of the rain. I fully believe that at Wallasey and Crosby 
and perhaps at Deal the attentions of collectors had a 
quite appreciable effect, as the larvee were abstracted in 
hundreds if not thousands. Possibly also the extreme 
difference of temperature between day and night which in 
dry seasons is always greater than in wet, and is some- 
times at the end of September particularly marked, may 
have had a fatal effect in so susceptible a larve; but be 
the agencies what they might, my point is that the bulk 
of these larvee were really destroyed, killed, before they 
pupated and that the absence of any noticeable descend- 
ants in 1889 was due to such destruction and not to the 
refusal of the pupe to produce moths at the proper time. 
Again although the years in which these larve so 
abounded were distinguished by exceptionally dry ante- 
cedent autumns, yet it may easily be objected that within 
the fifty-five years here embraced there have been quite 
half a dozen seasons equally distinguisbed by dry ante- 
cedent autumns, which have not been “‘galii” years. That 
