Specimens from the Depredations of Insects. 157 
I have invariably found, that they will soon be dislodged from 
the feathers, fall to the bottom of the case, and die in the course 
of two days. I have also made the experiment of introducing 
the common house-fly, the large blue-bottle-fly, and moths, into 
a case of birds so defended, through a small hole in the bottom 
of the case. The moment the flies enter the box, they begin to 
vomit a whitish, glutinous matter, they are much agitated, and 
the largest of them died in seven minutes. I have, in like man- 
ner, repeatedly introduced active American cockroaches, and 
these strong insects soon became uneasy, often rubbed their 
sides with their hind feet, and died in about an hour and a half. 
I next got a bird-skin full of living maggots, and placed it in 
my defended case ; in about three hours they were seen coming 
out in all directions, and fell to the bottom of the case, where 
they died. For large cases of birds, a pig’s or a sheep’s blad- 
der is sufficient ; for middle sized cases, a lamb’s or a rabbit’s 
bladder will do ; and for small ones, we may use a rat’s bladder. 
The turpentine evidently penetrates through the bladder, as it 
fills the case with its strong smell.” 
The powerful anthelmintic effect of oil of turpentine, corro- 
borates Mr Gibson’s account of its poisonous quality to the larvae 
of insects ; and its instantaneously killing perfect insects, must be 
familiar to the entomologist. I may here remark, that I have 
found the common receipt of dipping the pin, with which the 
insect is to be transfixed, in aquafortis, is by no means so speedy 
a method of putting an end to its sufferings, as applying a single 
drop of turpentine to the corselet. Though disappointed in the 
use of the pin dipt in acid, I never found the largest insects, 
Libellulce , Scar abaci , Blattce , or Scolopendrce, that could, 
for a moment, resist the application of oil of ’turpentine*. I 
ought to add, however, that my entomological pursuits have 
been few ; for the difficulty of speedily killing insects, without 
injuring the specimen, early gave me a distaste to that branch of 
Natural History. 
The difficulty of destroying the minute white acafr that in- 
fest the hairs of specimens in collections, is well known. On the 
* I have seen several coleopterous insects swimming about for some time in 
strong spirits ; but immersion in oil of turpentine, uniformly, was speedily fatal. 
