90 AN INTRODUCTION TO ENTOMOLOGY. 



margin; tarsi three jointed, the pulvillus wanting; cerci hornv, resem- 

 bling forceps. i. Forficulid^. 

 BB. Anterior wings parchment-like, thickly veined ; posterior wings folded 

 to the base ; tarsi five-jointed ; cerci soft, jointed or without joints. 

 C. Body oval, depressed ; head wholly or almost wholly withdrawn beneath 

 the pronotum ; pronotum shield-like, transverse ; legs compressed ; 

 cerci jointed ; rapidly running insects. 2. Blattid^e. 

 CC. Body elongated; head free; pronotum elongated; legs slender, 

 rounded ; cerci jointed or without joints ; walking insects. 

 D. Front legs fitted for grasping; cerci jointed. 3. Mantid^e. 

 DD. Front legs simple; cerci without joints. 4. Phasmid^;. 

 AA. Posterior femora fitted for jumping, i.e., very much stouter or very much 

 longer, or both stouter and longer than the middle femora; ovipositor horny, 

 free (except with the mole crickets); organs of flight of immature forms 

 inverted; stridulating insects. 



B. Antennae short ; tarsi three-jointed ; supposed organs of hearing situated 

 in the first abdominal segment; ovipositor short, composed of four sep- 

 arate plates; stridulating organs situated in hind femora and the costal 

 area of the tegmina. 5. Acridid.e. 



BB. Antennae long, setaceous ; tarsi four- or three-jointed ; supposed organs 

 of hearing situated in the anterior tibiae and also in the prosternum ; ovi- 

 positor elongated (except in the mole crickets) ; composed of four connate 

 plates. 



C. Tarsi four-jointed ; ovipositor (when exserted) forming a strongly com- 

 pressed, generally sword-shaped blade; the stridulating organs of male 

 limited to the anal area of the tegmina. 6. Locustidje. 



CC. Tarsi three-jointed ; ovipositor (when exserted) forming a nearly 

 cylindrical, straight, or occasionally upcurved needle ; the stridulating 

 organs of the male extend across the anal and median areas of the teg- 

 mina. 7. Gryllid^e. 



Family I.— Forficulid^.* 



{Earwigs.) 



This family includes only the earwigs. With these insects the 



first pair of wings are leathery, very small, 



^^•^^y^^s^^^^ without veins, and when at rest meet in a 



%Py^^^^^— I j straight line down the back, partially cov- 



$&MtyM \\^S^^ ering the second pair of wings. These 



K/T^llli^^^y wing-covers strongly resemble those of the 



^^j^XSjS^^^ rove-beetles. The second pair of wings 



Fig. 8 4 .-win g of Earwig. differ from those of other Orthoptera (Fig. 



84). They are furnished with radiating veins 



which extend from a point near the end of the basal third of the 



* ForficQlidae: forficula, a. pair of small shears. 



