CLASSIFICATION OF INSECTS. 63 



a more natural interpretation, as in the case of the 

 orders from XII. to XVL, inchisive. 



All of these graphic presentations are necessarily 

 extremely rough approximations to the actual facts, 

 and present even the authors' views in a very imper- 

 fect manner. Nevertheless, if conscientiously studied, 

 they will, it is hoped, help to give teachers some ideas 

 of the principles upon which a classification is based, 

 and prevent them from falling into the absurd but 

 natural mistakes often occasioned by the linear treat- 

 ment of types in the text. 



