LIFE IN THE INSECT WORLD. 15 



protect them from injury, but others are with- 

 out even this defence. The whole tribe of in- 

 sects is included in this division. 



Insects are also called articulated animals, 

 can you tell me what articulated means ? 



Harriet. Articulated means jointed does it 

 not? 



ftunt M. Yes ; and they are called articu- 

 lated, because, though without any regular sys- 

 tem of bones, they are composed of many jointed 

 parts. 



Vertebrated animals breathe through the 

 mouth by means either of lungs or of gills ; in- 

 sects are without these, but have in their place 

 little breathing tubes, placed along the sides, 

 the openings of which are called spiracles. 



All insects, when they arrive at maturity, 

 have six legs ; although caterpillars, which, as 

 I have told you, are still only in their youth, are 

 provided with sixteen little members which 

 serve the purpose of legs, and are very impor- 

 tant to them, by enabling them to cling to the 

 tree or leaf to which they have attached them- 

 selves, and to climb up fences and bushes. 



The eyes of insects are very remarkable. You 



