122 



THE UNIVERSE. 



in the autumn gives our green turf the appearance of a 

 starry sky. But in tropical America there are phosphores- 

 cent insects of far superior splendor. The great lantern-fly 

 can supply the place of a lamp with the bright light with 



62. Negro Hut lighted up with Luminous Beetles. 



which its monstrous head gleams. Sybille de Merian re- 

 lates that at Surinam she sometimes read the newspapers 

 by the aid of a single one of these Hemiptera. 1 



1 As is the case with so many vital phenomena, the phosphorescence of insects 

 is still far from being explained. Sir Humphry Davy and Treviranus attributed 

 it to a substance containing phosphorus, which is secreted from the fluids of the 

 animal, and beams like this substance by means of the oxygen of the air. This 

 would be a true combustion. The presence of phosphoric acid in the atmosphere 

 seems to give a certain amount of authority to this hypothesis. A German anat- 

 omist, the celebrated Cams, discovered that the eggs of these animals are them- 

 selves luminous, a very curious fact, and of a nature to throw some light upon 

 the question. 



