120 
LETTERS FROM ALABAMA. 
trunk of a tree ; and if the bright and conspicuous 
under- wings were visible, their retreat would be at 
once discovered; but when at rest, these are entirely 
concealed by the fore- wings, whose varied but 
sombre hues so exactly correspond with those of 
the bark as effectually to baffle the sight, unless 
the observer be very eagle-eyed. In pursuing 
these moths, particularly a very handsome one, 
whose hind-wings are scarlet, with two black 
bands {Gatocala Ilia), I have observed and admired 
this fact, though as a collector I have been ready 
to wish they were a little more readily seen. They 
haunt the interior of the forest, and fly usually in 
the afternoon ; the brilliant red of the wings is 
very visible in flight, and therefore their course is 
easily traced ; they fly swiftly and suddenly, and 
on alighting on the trunk of a tree, usually a little 
out of reach, are perfectly at rest in an instant, so 
that they appear to vanish; for though I have 
watched them to a tree only a few yards distant, 
and have kept my eye fixed on the spot ; on coming 
to it, I have looked in vain for the moth, and sup- 
posed that I have been deceived ; but, to be sure, on 
reaching up to the spot with a stick, the red wings 
flash out, and awajr flits the moth to another tree. 
There is a hymenopterous fly [Scolia quadrima- 
culata) which 1 have seen here occasionally, in the 
paths of the forest, towards evening. It is shaped 
like a bee, but is vastly larger, deep black, with 
four large yellow spots on the abdomen, placed in 
the form of a square; the wings have in a high 
degree that brilliant violet reflection which is found 
in many species of this order ; the legs are thickly 
clothed with, coarse black hair. The first time 
I saw it, it was fluttering ' along the ground, half 
