186 ELEMENTS OF COMPARATIVE ZOOLOGY. 



well-known wireworms. The fireflies are interesting from 

 their phosphorescent powers. Underneath the abdomen 

 are the light-giving spots. Much attention has been given 

 to this light-producing apparatus in the hopes of obtaining 

 a solution of the problem of producing light without heat. 



A large number of beetles have the terminal portion of 

 the antennae, like that of the June-bug, with a club 

 formed of leaf-like joints. These are known as Scara- 

 baaans, from the sacred beetle (Scarabceus) of the Egyptians 

 which belongs to the group. These sacred forms are repre- 

 sented in our country by the tumble-bugs, which lay their 

 eggs in balls of manure which they trundle along the road 

 until they find a suitable place to bury them. From the 

 similar habits of the Scarabaeus the Egyptians worked out 

 quite a symbolism. " The ball which the beetles were 

 supposed to roll from sunrise to sunset represented the 

 earth; the beetle itself personified the sun, because of the 

 sharp projections on its head, which extend out like rays of 

 light; while the thirty segments of its six tarsi represented 

 the days of the month." Other members of the Scara- 

 baeans, like our June-bugs, are vegetarians and do no little 

 damage. As larvae they feed upon the roots of the grass 

 and other plants; as adults they devour the foliage. In 

 the tropics occur Scarabaeans of enormous size, some having 

 bodies six inches in length. 



The long-horn beetles live as larvae in the solid portions 

 of trees and shrubs, where they bore long tubes. The 

 species usually have long antennae, and many of them are 

 beautifully colored. Structurally much like these borers 

 are the shorter and more oval leaf -beetles, which do so much 

 damage. Here belong- the cucumber-beetles, the Colorado 

 potato-beetle, and others which feed upon the grape, the 



