2 24 ANIMALS OF LAND AND SEA 



Beneath them you sometimes see a bright spot following them 

 along caused by the beams of light from the luminous patch 

 on their under side. Not only are the adults luminous, but 

 also the grubs or larvae, the pupae, and the eggs. 



In parts of the West Indies and in Mexico they are kept in 

 little cages of wicker work or wire netting or used by women 

 for personal adornment, entangled in their hair or fastened 

 to their clothing. They are captured by waving a burning 

 coal toward which they fly. When kept as pets great care is 

 taken of them. They are fed each evening on pieces of crushed 

 sugar cane, and bathed twice every day in tepid water. 



The common lire-flies are found in almost every country, but 

 the greater part are from America, especially the warmer por- 

 tions. They belong to a very different group of beetles called 

 the Lampyridae. Their luminous organs are on the under side 

 of the abdomen, more or less differently distributed in the 

 different kinds, but usually near the tail. Most of them 

 give out their light in flashes, which are different for each kind. 

 In some the females have no wings and look Hke larvae; these 

 wingless females are called in England glow-worms. With us 

 glow-worms are the wingless females of some kinds, and the 

 larvae of others. The grubs or larvae of these hre-flies are also 

 luminous; they are predaceous, feeding on snails, earth-worms, 

 and other creatures. The embryos within the eggs are also 

 more or less luminous. A few of our fire-flies have the light 

 organs very much reduced so that they give out only a little 

 spark, and some, which fly by day, produce no light at all. 

 The young of some of the oriental sorts live under water feed- 

 ing on aquatic snails, and are the only phosphorescent crea- 

 tures in fresh water. 



The so-called glow-worms in New Zealand are found in 

 colonies in caves, mines, and other damp and shaded situations 

 where they spin a mass of sticky threads upon which their 

 prey becomes entangled somewhat after the manner of the 

 spiders. These are not real glow-worms, but the young or 

 larvae of a sort of fungus gnat. The hinder end of the body is 



