COLEOPTERA. 
435 
the appearance of being plaited. The luminous matter occupies the 
inferior part of the last two or three annuli, which differ in colour 
from the rest, and are usually yellowish or Avhitish. The light they 
diffuse is more or less vivid, and greenish or whitish, like that of the 
different kinds of phosphorus. It seems that they can vary its action 
at pleasure, a fact particularly observable when they are seized or 
held in the hand. They live a long time in vacuum and in different 
gases, the nitrous acid, muriatic and sulphurous gases excepted, in 
which they soon expire. Placed in hydrogen gas, they, sometimes 
at least, detonate. They continue to live after the excision of this 
luminous portion of their abdomen, and the part thus separated pre- 
serves its luminous property for some time, whether it be submitted 
to the action of various gases, be placed in vacuum, or left exposed to 
the air. The phosphorescence depends on the softness of the matter, 
rather than on the life of the animal. When apparently extinct it 
may be reproduced by softening the matter rvith water. The Lampy- 
rides emit a brilliant light when immersed in warm water, but in cold 
water it becomes extinguished ; this fluid seems to be the only dis- 
solving agent of the phosphoric matter *. 
They are nocturnal Insects ; the males, like Phalenae of the same 
sex, are frequently observed circling round the blaze of candles, &c., 
from which we may conclude that this phosphoric light, which is 
chiefly given out by the females, is intended to attract the former 
to the latter : and if, as De Geer asserts, the larvae and pupae of 
the species found in France are luminous, we are only to conclude 
that the phosphoric matter is developed at the earliest period of 
their existence. It has been said that some males were destitute of 
this luminous property — but they still possess it though in a very 
small degree. As nearly all the Lampyrides of hot climates, males 
as well as females, are provided with wings and are extremely nu- 
merous, they present to their inhabitants at night an interesting spec- 
tacle, a continued illumination, proceeding from the myriads of 
luminous points which like little wandering stars traverse the air 
in every direction. 
According to M. Dufour — Ann. des Sc. Nat., Ill, p. 225 — the 
alimentary canal of the female of the common European Lampyris, 
the splendidula, is about twice the length of the body. The oeso- 
phagus is extremely short and immediately dilated into an abbre- 
viated crop separated from the chylific ventricle by a valvular stran- 
gulation. The latter is very long, smooth, turgid, and cylindrical 
for two thirds of its length, then intestiniform. Tho small intestine 
is very short and flexuous, presenting an enlargement (perhaps not 
constant) representing a caecum, and terminated in an elongated 
rectum. 
Certain Brazilian species, in which the antennae of the males con- 
sist of more than eleven joints formed like the laminae of a feather, 
* Besides the experiments detailed in the Ann. de Chimie, see the Ann. Gdn^r. des 
Sc. Phys., of Messrs. Bory de Saint-Vincent, Drapiez et Van Mons. VIII, p. 31, 
■where will be found the researches of M. Grotthuss on the phosphorescence of the 
Lampyris italica. 
P p2 
