354 INSECTA. 



• 

 separated preserves its luminous property for some time, whether 



it be submitted to the action of various gases, 1)C 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 with 

 water. The Lampyrides emit a brilliant light when immersed in 

 warm water, but in cold water it becomes extinguished: this fluid 

 seems to be the only dissolving agent of the phosphoric matter(l). 



They are nocturnal Insects; the males, like Phalenai of the same 

 sex, are frequently ol)served circling round the lilaze of candles, Sec, 

 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 DeGeer asserts, the larv?e and pupse 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, 

 ihe 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 vei-y long, smooth, lurgid and cylindrical 

 for two thirds of its length, then intestiniform. The small intestine 

 is very short and flexuous, presenting an enlargement (perhaps not 

 constant) representing a caecum, and terminated in an elotigated 

 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, 

 have been separated from the genus Lampyris of Linnaeus. They 

 constitute the Amydetes, HoflF., Germ. (2) 



(1) Besides the experiments detailed in the Ann. de Chimie, see the Ann. 

 G6n^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 phospho- 

 rescence of the Lampyris italica. 



(2) Lampyris plumicomis, Lat., Voy. de MM. Humboldt and Bonpl., Zool. 

 XVI, 4; — Jimyddes apicalls. Germ., Insect. Spec. Nov., p. 67. 



