CLASS INSECTS. 



441 



541. The neuroptera are distinguished from other mas- 

 ticating insects by the structure of their wings, four in 

 number ; these are all membranous, transparent, of extreme 

 delicacy, and of equal utility for flight. The body of such 



Fig. 466. Cockroach. 



insects is generally soft, and very elongated. Finally, some 

 undergo a complete metamorphosis, others only a semi-meta- 

 morphosis. This order comprises the libellube (Fig. 469), 



Fig. 467. House Cricket. 



the agrions (Fig. 171), the ephemera (Fig. 458), the ant- 

 lion (Fig. 115), the phryganidse, the termites, &c. 



These last insects, known also by the name of white ants, 



