HEMEROBIUS. 
259 
mences a chrysalis, which in the space of about 
twenty^ days affords the complete insect. It is 
wonderful, as Reaumur very justly observes, that 
an insect with such an expanse of wing should be 
contained within the small compass of the silken 
ball of the chrysalis. 
The Hemerobius Perl a, like its larva, is of a 
predacious nature, living on the smaller kind of 
flying insects. 
Hemerobius chrysops greatly resembles the pre- 
ceding, but differs in having the body and thorax 
marked by black spots, and the wings by dusky 
reticular variegations. 
* According to Albin the larva incloses itself in the baH in 
August, and the fly emerges in the following May. Reaumur 
observes that those which change to chrysalis early in summer 
emerge from it in about three weeks, while those which change 
in September continue in chrysalis till the following spring. 
