ON THE SERRICORNES. 369 



oil, shone but feebly, and very soon became extinct in water. 

 Another shone with the same vivacity in the air, and for 

 a longer time ; the phosphorus of these insects shines equally 

 in the barometric vacuum. The author has recognised that 

 the phosphorescence is a property, independent of the life of 

 these insects, and that it is attached rather to the degree 

 of softness of the phosphoric substance. Dryness suspends 

 the light ; softening in water regenerates it, but only after a 

 certain given time of dessication. Reaumur and Spallanzani 

 have made the same observation respecting the pholades and 

 medusas. 



By plunging the lampyrides alternately into lukewarm and 

 cold water, they shine with vivacity, in the first, but are extin- 

 guished in the last ; in hot water the light disappears by 

 little and little. M, Carradori has tried on the lampyrides 

 and their phosphorus, the action of the different saline and 

 spirituous fluids, in which they have exhibited the same sort 

 of phenomena as the other phosphoric animals. These expe- 

 riments have proved that the phosphoric matter of the 

 lampyris undergoes a dissolving action only through the 

 medium of water. 



The larva of lampyris has much resemblance to the female ; 

 it is provided with six scaly feet placed on the first three 

 rings. This larva, though furnished with strong jaws, which 

 might lead one to suppose that it was carnivorous, yet lives 

 on herbs and the leaves of different plants. It walks very 

 slowly and by the assistance of the hinder part of its body ; 

 as soon as it is touched, it draws back its head and remains 

 immoveable ; when it is suffered to want humid earth it 

 becomes feeble and languishing. 



When insects are about to be transformed into the nymph 

 state, the skin is usually cleft or broken in the middle of 

 the top of the head, and thus leaves a sufficient aperture to 

 give a passage to the rest of the body. The larva of the 



VOL. XIV. 2 B 



