LETTERS ON ENTOMOLOGY. 139 
from the three last ventral segments of the ab- 
domen, but sometimes appears above, between 
the dorsal segments or rings. Though most of 
the females of the different species of Lampyris 
are without wings, all are not so unfortunate; 
the female of Lampyris Italica, which is common 
in Italy, and has even, been caught in Hertford- 
shire, is winged. 
Elater noctilucus, an insect of the beetle tribe, 
is luminous in a higher degree. It is about an 
inch long, and gives its principal light from two 
tubercles placed upon the thorax, or upper part 
of the body; but there are also two luminous 
spots under the wings, which show when the 
insect flies, and give it a very beautiful appear- 
ance, particularly as, when the body is stretched, 
it seems filled with light, which shines out be- 
tween the segments. This light is so brilliant, 
that the smallest print may be read by moving 
one of them along the lines ; and in the West 
Indian islands, the natives used to employ them 
as lamps : when travelling, they would tie one 
to each great toe, and needed no other light. 
These useful insects, which they call Cucuij, are 
also extremely beneficial by destroying the gnats, 
which you know are such a pest in those 
countries : for this purpose they catch the fire- 
