12 THE ENTOMOLOGIST’S RECORD. 
I had no reason to hope for similar success, the season was already © 
late, and I should have considered myself one of the happiest~ of 
naturalists if a dozen of the larve had hybernated successfully; | 
but even this was not to be. The dates of the four moults preceding ~ 
hybernation: were as follows :—I1st moult, August 10th ; 2nd moult, 
August 18th; 8rd moult, August 26th; 4th moult, September 10th. 
After the 4th moult the larve ceased to feed, although they were 
supplied with poplar leaves. Until this time I had kept them on a 
large branch of poplar, placed in a vase full of water and stood in a 
breeding-cage. The larvee rested here and there on the branches, and 
by their bluish-grey colour and flattened form assimilated perfectly 
with the bark of the branches, and did not move the whole of the 
winter. Knowing that heat and drought were alike injurious I placed 
the breeding-cage in the garden, against a north wall, taking care to 
damp it when the weather was dry. All these precautions were in 
vain, and in March the larve began to fall from the branches, quite 
dried up, and by the end of the month there were only four left. 
Then I tried a last experiment—I planted a young poplar in my 
garden in a position well exposed to the sun, placed on it one of the 
remaining larvee, covered it with muslin, and left it to fate. The 
weather was bad, but about April 10th the sun shone on the poplar 
a part of the day, and this appeared to waken the larva, which nibbled 
one of the buds at the end of the branch. Seeing this I placed the 
three other larve on the poplar, but it was already too late, for after 
eating a little they died, whilst the first one continued to nibble the 
buds, and about the middle of May, when the leaves commenced to 
develop, the caterpillar ate much and commenced to grow, and at the 
end of the month it moulted for the fifth and last time. This moult 
was long and laborious; the larva remained eight days without feed- 
ing, then it shed its skin and in a short time became very large, and I 
suspected it would prove to bea ? on this account. On June 20th it 
spun its cocoon, which is soft and greyish-yellow in colour. On the 
23rd the pupa was formed and one could see it through the cocoon, 
and I had only to await the imago. The experiment was concluded. 
It is necessary to keep the larve in the sun even during the winter, 
without this precaution they will die of hunger even by the side of the 
leaves. On July 15th the imago emerged, a female, as I had pre- 
dicted. The pupal state had lasted three weeks. The imago emerged 
about 8.0 a.m., and I intended to take it into the woods in the evening, 
in order to attract a male, but there was a heavy storm and it was 
impossible to go out. 
As far as I am concerned there is nothing more to add. It appears 
absolutely necessary that the larvee should pass the winter out of doors 
on a growing poplar well exposed to the sun (a precaution necessary in 
rearing all the Lasiocampids, each on the plant that nourishes it). It 
is the only possible means of obtaining a successful result. I have 
since learned that M. lAbbé de Joannis was also unsuccessful in 
hybernating his larve ; he kept a part of his larvee out of doors in the 
winter, but not in the sun. 
