THE ENTOMOLOGIST. 
Vou. XXV.) FEBRUARY, 1892. [No. 845. 
THE PAST WET SUMMER AND ITS PROBABLE EFFECT 
UPON THE DEVELOPMENT OF LEPIDOPTERA. 
By Rosert Apxw, F.E.S. 
THE year 1891 will be long remembered by entomologists 
on account of its cold, wet summer. It is probable that such 
abnormal meteorological conditions would have an effect upon 
the development of Lepidoptera, and any note relative thereto 
should be of interest. I therefore venture to record a few cases, 
taken from my note-book, in which the emergence of a species 
from pupa appears to have been spread over an unduly long 
period, or the growth of larve unusually prolonged, presumably, 
by reason of the conditions referred to. | 
From some twenty pupz of Sesia ichneumoniformis obtained 
at the end of June, the first imago emerged on 12th July ; others 
followed at intervals until 22nd August. Rather more than half 
the total number produced perfect insects, the remainder dying 
when fully formed. The species appears to emerge on hot 
sunny mornings, between 7 and 10 o’clock, and it is probable 
that the large percentage of losses may have been due to the 
comparatively small number of suitable occasions for emergence. 
Dianthacia carpophaga var. capsophila: from a number of 
larve taken in the previous autumn the imagines commenced to 
emerge on 8rd July, and continued to appear until 24th August. 
A larva of Plusia gamma, taken 12th September, produced an 
imago in the middle of November. 
A brood of Eugonia erosaria fed up from ova on a growing oak 
tree. The ova commenced to hatch on 2nd July, and the larve 
fed up very irregularly, some reaching the pupal stage, while 
others were still quite small. The first moth appeared 8th 
August, and the last 30th September. Some few larve that had 
fed on until within a few days of the latter date, assumed the 
pupal state, but did not produce moths. 
From some sixty larve of Gnophos obscuraria, collected at 
ENTOM.—FEB. 1892. D 
