CLASSIFICATION 311 



Order 5. ORTHOPTERA 



The Cockroaches, Leaf-insects, Stick-insects (Plate I, A), 

 Grasshoppers, Locusts, Crickets, and other insects comprised 

 in this order have biting mandibles, forewings firm in 

 texture and relatively narrow, the ampler hindwings being 

 folded beneath them when at rest. There are jointed 

 cercopods at the tail-end and (in the female) an ovipositor 

 (Fig. 36, A). 



Order 6. PLECOPTERA 



The Stoneflies have biting mandibles, though these are 

 often reduced, and two pairs of membranous net- veined 

 wings, the hind pair usually folding ; there are tail cercopods 

 often elongate. The insects develop from aquatic nymphs 

 (Plate X, B) which live submerged in streams and breathe 

 through tufted gills on the thorax. 



Order 7. ISOPTERA 



The Termites (Fig. 64) and Embiids have the two pairs 

 of wings closely alike and incapable of folding (many forms 

 are quite wingless). They have biting jaws and short 

 cercopods. 



Orders. CORRODENTIA 



The Booklice and their allies have their wings (when 

 present) delicate and membranous, the forewings both 

 longer and broader than the hindwings. There are biting 

 mandibles, and the inner lobes of the maxillae are elongate 

 '* picks." Cercopods are absent. 



Order 9. THYSANOPTERA 



These insects, generally known as Thrips, have short 

 feelers, and the jaws adapted for piercing and sucking, the 

 mandibles being slender and needle-like. The wings of 

 both pairs are delicately membranous, narrow, and fringed. 



