38 NATURE STUDY 



creatures, but that does not affect our 

 purpose. We should no doubt remark that 

 a great variety of insects had harboured 

 under that stone, but this remark would be 

 incorrect. There would be only one insect 

 among them the earwig. What makes the 

 combination interesting is that each of those 

 little creatures represents a whole class. 



Proceeding to examine them in detail, 

 and directing our attention to the general 

 construction of their bodies and the character 

 of their organs of locomotion, we see that, 

 while they have much in common, they 

 have many points of difference. We might 

 tabulate our observations thus : 



(1) The woodlouse has no distinct sepa- 

 ration of the body into head, thorax, and 

 abdomen, has fourteen legs, and no wings. 



(2) The spider has the head and thorax 

 in one piece, clearly separated from the 

 abdomen, has eight legs, and no wings. 



(3) The centipede has a distinct head, and 

 the rest of the body composed of nearly equal 

 divisions, has thirty legs, and no wings. 



(4) The earwig has a distinct separation 

 of the body into head, thorax, and abdomen, 



