PHOSPHORESCENCE OF ANIMALS. 155 



darkness, the spot appointed for the lover's rendezvous,"* 

 is but a pretty fiction ; for the glow-worm shines in its 

 infant state, in that of the larva, and when in its aurelian 

 condition. Of the dark depths of the ocean it may be 

 safely affirmed that no organized creation lives or 

 moves in its grave-like silence to require this fairy aid. 

 Fiction has frequently borrowed her creations from 

 science. In these cases science appears to have made 

 free with the rights of fiction. 



The glow-worms (lampyris noctiluca), it is well known, 

 have the power of emitting from their bodies a beautiful 

 pale bluish- white light, shining during the hours of 

 night in the hedge-row, like crystal spheres. It appears, 

 from the observations of naturalists, that these insects 

 never exhibit their light without some motion of the 

 body or legs; from this it would seem that the 

 phosphorescence was dependent upon nervous action, 

 regulated at pleasure by the insect ; for they certainly 

 have the power of obscuring it entirely. If the glow- 

 worm is crushed, and the hands or face are rubbed with 

 it, luminous streaks, similar to those produced by 

 phosphorus, appear. They shine with greatly increased 

 brilliancy in oxygen gas and in nitrous oxide. From 

 these facts may we not infer that the process by which 

 this luminosity is produced, whatever it may be, has a 

 strong resemblance to that of respiration ? 



There are several varieties of flies, and three species of 

 beetles of the genus Elater, which have the power of 

 emitting luminous rays. The great lantern-fly of South 

 America is one of the most brilliant, a single insect 

 giving sufficient light to enable a person to read. In 

 Surinam a very numerous class of these insects are 

 found, which often illuminate the air in a remarkable 

 manner. In some of the bogs of Ireland a worm exists 

 which gives out a bright green light; and there are 



* Dumeril. 



