AN 



INTRODUCTION 



TO 



ENTOMOLOGY. 



LETTER XXVIII. 



DEFINITION OF THE TERM INSECT. 



W HAT is an insect ? This may seem a strange ques- 

 tion after such copious details as have been given in my 

 former Letters of their history and economy, in which it 

 appears to have been taken for granted that you can an- 

 swer this question. Yet in the scientific road which you 

 are now about to enter, to be able to define these crea- 

 tures technically is an important first step which calls for 

 attention. You know already that a butterfly is an insect 

 — that a fly, a beetle, a grasshopper, a bug, a bee, a. 

 louse, and flea, are insects — that a spider also and centi- 

 pede go under that name; and this knowledge, which 

 every child likewise possesses, was sufficient for compre-. 

 hending the subjects upon which I have hitherto writte,n. 

 But now that we ai*e about to take a nearer view of thern — ■ 

 to investigate their anatomical and physiological charac- 



VOL. JTI, B 



