CHAPTER VI. 



Order III.— ORTHOPTERA.* 



{Cockroaches, Crickets, Grasshoppers, Locusts, Earwigs, et al.) 



The members of this order hare four wings: the first pair are 

 thickened, and usually overlap when at rest ; the second pair are 

 thinner, and are folded in plaits longitudinally. The mouth parts are 

 formed for biting. The metamorphosis is incomplete. 



The order Orthoptera includes some of the very common and 

 best known insects. The most familiar representatives are the cock- 

 roaches, crickets, grasshoppers, locusts, and katydids. 



Although the song of the katydid and the chirp of the cricket 

 are most often associated with recollections of pleasant evenings 

 spent in the country, we cannot forget that to members of this order 

 are due some of the most terrible insect scourges man has known. 

 The devastations caused by great swarms of migratory locusts are 

 not only matters of historical record, but are too painfully known to 

 many of our own generation in the Western States. 



With the exception of a single family (Mantidse), the members of 

 this order are as a rule injurious to vegetation. And many species 

 are quite apt to multiply to such an extent that their destruction of 

 plant life becomes of economic importance. 



In the Orthoptera the two pairs of wings differ in structure. 

 The front wings are leathery or parchment-like, forming covers for 

 the more delicate hind wings. These wing-covers have received the 

 special name tegmiua. Excepting in the first family (the earwigs), 

 the tegmina of the Orthoptera arc thickly reticulated with a net-work 

 of veins, and usually overlap at the tips. The position and struc- 

 ture of the tegmina differ in the different families, and afford good 

 characters for separating them. The more important veins of the 

 tegmina usually divide them into three more or less well-marked 

 fields or areas. These have been named, beginning with that bor- 

 dering on the front margin of the wing, the costal, median, and anal 

 areas, respectively. The hind legs are thickly netted with veins. 



* Orthoptera: orthos (opOoS), straight; pteron (itvepov), a wing. 



