236 THE ANIMAL KINGDOM. 



on the surface of the earth, which by the destructive powers 

 of these insects is completely removed, and their manure 

 left in its place, so that the fertility of the ground is much 

 increased (often tenfold) after their visits. 



The thousands of species of insects which exist, render it 

 impossible in a work like this, even to name them, but under 

 the separate orders will be given a slight outline of the 

 more important. 



Insects are divided, according to the character of their 

 wings, into nine orders. 



PIG. 22. THE STAG BEETLE (Lucanus cervus). 



1. COLEOPTEBA (Black-winged) . 



The Coleoptera are those insects generally denominated 

 Beetles, they have four wings, the two outer of 

 which are not used to fly with, but as cases to cover 

 and protect the other two ; they are called " elytra," 

 are horny and firm in texture, and in some cases, 

 as the Diamond Beetle and Musk Beetle, beautifully 

 ornamented; the under pair of wings fold trans- 

 versely so as to pack up under the outer ones, which 

 are shorter. All Beetles live but one season, both 

 sexes die before winter, leaving nothing but their eggs 

 to continue the species, the larvae which come from 

 these are very destructive, eating most voraciously ; for 



