276 OBSERVATIONS ON INSECTS. 



ever before witnessed. It was not till after a fort- 

 night had elapsed from the time of these insects 

 being first noticed that I had an opportunity of 

 seeing them myself, during which interval their 

 numbers had been greatly thinned by fumigations 

 of tobacco and other substances employed as a 

 means of destroying them ; nevertheless they were 

 still in immense profusion, and my informant told 

 me that in the first instance the greater part of 

 the ceiling, towards the window of the room, was 

 so thickly covered as not to be visible. The ex- 

 act day of the month on which these insects first 

 shewed themselves was not noticed, but, as far as 

 could be remembered, it was about the 17th of 

 September. They appear to have entered the room 

 very early in the morning, by a window looking 

 due north, which had been open during a part 

 of the night, being first observed between eight 

 and nine A. M. A few were noticed in the ad- 

 jacent rooms facing the same way, although, com- 

 paratively speaking, in no great quantity; perhaps, 

 in consequence of the windows of those rooms not 

 being opened at quite so early an hour. None 

 at all, however, had been seen in the house pre- 

 viously to that day. We are at present so igno- 

 rant of the habits and economy of the minuter 

 tribes of insects, that it is not easy to give an ex- 

 planation of this phenomenon. It would be inte- 

 resting to know whether the above had been all 

 bred in the immediate neighbourhood, and at the 

 same time, or whether they were swarms that had 

 collected from different quarters for the purpose of 



