146 PHOSPHORIC INSECTS. 



of the light of glowworms. According to Carus, 

 this luminous organ " constantly receives a cur- 

 rent of a liquid equivalent to blood." This flow, 

 in his opinion, is the cause of the rhythmical 

 character of the luminous emanation, as seen in 

 Lampyris italica. 



Gueneau de Montbelliard showed in 1 782 (Nouv. 

 Mem. de FAcad. de Dijon, vol. ii. p. 80) that the 

 eggs of Lampyridce, which are small yellowish 

 spheres, appear also phosphorescent in the dark. 

 Carus has confirmed this observation, and assures 

 us, at the same time, that the larvae of these in- 

 sects emit a greenish phosphoric light, a fact 

 which had been observed by Treviranus as early 

 as 1802. Some authors have asserted that the 

 chrysalis of the glowworm is slightly luminous. 



Fig. 26. 



Other Coleoptera are exceedingly phosphores- 

 cent. Such are the numerous species belonging 

 to the genus JElater, known to the English as 

 Fire-flies, and of which E. nodilucus (fig. 26) of 



