CHAPTER V 

 ORDER ORTHOPTERA* 



Grasshoppers, Crickets, Cockroaches, and others 



The winged members of this order have two pairs of wings; the fore 

 wings are more or less thickened, but have a distinct venation; the hind 

 wings are folded in plaits like a fan when at rest; there are many forms in 

 which the wings are vestigial or even wanting. The mouth-parts are formed 

 for chewing. The metamorphosis is incomplete; the nymphs are terrestrial. 



The order Orthoptera includes some of the very common and best- 

 known insects. The most familiar representatives are those named 

 above. 



Although the song of the katydid and the chirp of crickets 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 (Mantidce), 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 vegetation 

 becomes serious. 



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

 wings are parchment -like, forming covers for the more delicate hind 

 wings. These wing-covers have received the special name tegmina; they 

 are furnished with a fine network of veins, and overlap at the tip at 

 least. There are many species in which the wings are rudimentary, 

 even in the adult state. Such adults resemble nymphs; but in the case 

 of the jumping Orthoptera, where this peculiarity most often occurs, 

 nymphs can be distinguished by the fact that the rudimentary hind wings 

 are outside of the fore wings, instead of beneath them, as in the adult 

 state. 



There are six families of well-known insects in the order Orthoptera 

 which can be separated by the following table. 



A. Hind femora fitted for jumping, i.e., very much stouter or very much longer, 

 or both stouter and longer, than the middle femora; organs of flight of immature 

 forms inverted; stridulating insects. (The Saltatorial Orthoptera.) 

 B. Antennae long and setaceous, except in the mole-crickets and sand-crickets; 

 tarsi three- or four- jointed; organs of hearing situated in the fore tibiae; oviposi- 

 tor elongate, except in the mole-crickets and sand-crickets, with its parts 

 compact. 

 C. Tarsi four-jointed; ovipositor, when exserted, forming a strongly compressed, 



generally sword-shaped blade, p. 50 Tettigoniid^e 



* OrthSptera: orthos (6p06s), straight; pteron (irrepov), a wing. 



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