CLASSIFICATION 13 



Antennse usually few-jointed. Mouth parts suctorial. Prothorax usu- 



FIG. 22. Benacus grisciis. Slightly reduced. 



FIG. 23. Head louse, 

 Pediculus capitis, female. 

 Length, 2 mm. 



FlG. 24. Chrysopa 

 plorabunda. Slightly 



reduced. 



ally large. Wings usually present, except in the parasitic forms. Eigh- 

 teen thousand species. Three suborders: 



Suborder Heteroptera. Wings four, folded 

 flat; front wings thickened basally, membranous 

 apically (hemelytra), overlapping obliquely; hind 

 wings membranous. Head not deflexed. Ex- 

 ample, Benacus (Fig. 22). About twelve thou- 

 sand species. 



Suborder Homoptera. Wings four, sloping 



roof-like, similar and membranous or front pair somewhat coriaceous 



throughout. Head deflexed. Example, 

 Cicada (Fig. 207). Six thousand species. 

 Suborder Parasita. Wingless. Eyes 

 simple or none. Thoracic segments inti- 

 mately united; tarsus with a single claw. 

 Integument thin. Parasites upon mammals. 

 Example, Pediculus (Fig. 23). Some fifty 

 species are known. 



10. Neuroptera. Metamorphosis in- 

 direct. Antennae conspicuous. Mouth 

 parts mandibulate. Prothorax large. 



Wings almost always four, membranous, subequal or else hind pair 



FIG. 25. Bitlacus slrigosits. Na- 

 tural size. 



