OF OTJR LEPIDOPTEROUS INSECTS. 
57 
The brown hairy larva, commonly known as the “ woolly bear,” is 
that of the beautiful tiger-moth; and there is one genus containing 
only two species, in which the larvae are furnished with tufts of 
exquisitely branched hairs, resembling palms when magnified. 
These are the vapourer moths, one of which is rare, but the other 
is very common even in London. The females of these two moths 
are entirely without wings. 
There is a curious tendency with some insects, of which there 
are instances amongst the Bombyces, to become darker in colouring 
when they are bred in Scotland or other northern localities. This 
tendency to melanism, as it is called, has never been satisfactorily 
explained or accounted for. Melanism sometimes affects the whole 
colouring of an insect, but sometimes the variation takes the form 
of darker markings, and some of them quite distinct from those 
of the normal form. The most striking instance of this is in one of 
our common ermines (Spilosoma lubricipeda ), which in Yorkshire and 
Lancashire varies in a remarkable manner. Usually yellowish with 
small black spots, it becomes in the north much more yellow with 
a great variety of black markings, until nearly the whole insect is 
black, with the wing-nervures and a larger or smaller patch in the 
centre of the forewings yellow. 
Many of the Bombyces are liable to variation, the common tiger- 
moth furnishing one of the most curious instances. 
The Noctuae form a group contrasting greatly with the Bombyces, 
for although they are very numerous they are all closely allied in 
structure and appearance. Mostly dull in colouring, they are 
usually less generally attractive than either the Bombyces or the 
Geometers; but to those who study them this group is one of 
the most interesting. They are thick-bodied, sweet-loving insects, 
with well-developed probosces, and their penchant for sweets has 
been largely taken advantage of by collectors to effect their capture. 
It is for these moths that “ sugar”—a mixture of treacle, sugar, 
and beer, with the addition of a small quantity of rum or essence 
of Jargonel pear—is painted on trees, etc. The mixture is smeared 
on the stems of rough-barked trees, on the side away from the 
wind. All moths fly against the wind, and as the JNoctuse have 
an acute sense of smell they will come from long distances to sip 
the sweets provided for them. They sit out of the wind, all round 
a patch of sugar, taking care not to soil their feet with it, and sip 
it with their long probosces. On a favourable night I have often 
seen eighty or more moths sitting round one patch of sugar. 
This method of attracting the .Noctum is not by any means always 
successful, and it is difficult to find out what are the conditions 
that are favourable or the reverse. A dark, close night, with 
a southerly or westerly wind, is usually considered the best, but 
I have had many a failure on nights that seemed perfect. There 
are natural sweets which the moths always prefer to any artificial 
mixture. 
In the Spring an early group of the Yoctuse may often be taken 
in numbers feeding on the blossom of the sallows, and it is useless 
