80 THE CANADIAN ENTOMOLOGIST. 
Strips of white cloth nailed upon the trees were very convenient to 
receive the sugar, though not necessary. One afternoon, while preparing 
my baits for evening, a fine Grafta Interrogationis hovered around the 
tree for a moment and then lit close by, and unrolling its proboscis, feasted 
on the nectar. While engaged in this absorbing operation I readily cap- 
tured it between thumb and finger. In some localities where rare species 
are to be found, it may be worth while to try sugaring for butterflies as. 
well as moths. 
The vapor of hydrocyanic acid in the poison-bottle, as a rule, did not. 
change the colors of specimens even after prolonged exposure. But a 
single moth of those collected, a pinkish Cramdus, was faded by it, 
changing to olive brown. 
At my suggestion cyanide of potassium was adopted by the American 
Museum of Natural History, to preserve their Entomological collections. 
from the ravages of insects. At first small tin boxes were used, but the 
salt chrystallized upon the tin and made its way over the edge and down 
the sides of the receptacle, staining the cabinet drawers. Finally small 
glass capsules were used to contain the poison, and proved satisfactory. 
The vapors render it unpleasant to work over the drawers while the cap- 
sules are in them, but with the temporary removal of these the 
inconvenience ceases. A fly or other small insect introduced into one of 
the cases, dies in a very short time, and the protection against Dermestes 
is very complete, though of course it is hardly advisable to use this method 
where the drawers are not nearly air-tight. Still I think that every Ento- 
mologist would find a single tight receptacle thus poisoned very useful as 
a sort of quarantine for suspected specimens. Even delicate green 
Geometrae, after being in an atmosphere of prussic acid vapor for months, 
have, so far, shown no change in color. 
THE South London Entomological Society, which, though only nine 
months old, has been extremely successful, held on Thursday evening 
last, at Dunn’s Institute, Newington Causeway, a very interesting exhibition. 
of collections of insects, chiefly British Lepidoptera. The collections. 
were made by the members themselves, all amateurs, and do them the 
greatest credit. The room was densely crowded, and the exhibition was: 
a great success. 
