426 COLEOPTERA, ORTHOPTERA, XEUROPTEKA- 



die. In the first of these states they do the most 

 injury. 



The following description of the orders of insects 

 was suggested by those of Burmeister, Harris, and 

 Glover. 



1. Coleoptera — Beetles. These undergo a perfect 

 change of form, as described above. They have a 

 mouth, furnished with jaws formed for biting ; two 

 thick, wiry covers, meeting in a straight line on the 

 top of the back ; and two filmy wings underneath 

 them, folded transversely. The larvae are grubs ; 

 the pupae with wings and legs distinct and uncon- 

 fined. 



2. Orthoptera — Cockroaches, crickets, grasshop- 

 pers, straight-winged insects. These have only an 

 imperfect change of form ; and in their mature state 

 are like grasshoppers. They have a mouth like 

 the preceding, furnished with jaws for biting or 

 masticating; two thick, opaque upper wings, over- 

 lapping a little on the back ; and two larger, thin 

 wings, folded in plaits, like a fan. The larvae and 

 pupae are active, but wingless. 



3. Neuroptera — Net-veined insects. These have 

 a perfect change of form : the mouth is furnished 

 with jaws for biting. They have four wings, of 



