134 Cockroaches, Locusts, Grasshoppers, and Crickets 



will move slowly on, walking and hopping for many miles, eating every 



green weed and grass-blade in their path, but this is only a limited and 



local sort of migration. 



Almost all the Acridiidae, despite the many species in the family, are 



readily recognizable as locusts 

 or grasshoppers short-horned 

 grasshoppers they may be called, 

 to distinguish them from the 

 meadow green grasshoppers with 

 long thread-like antennae because 

 of their general similarity in ap- 

 pearance and habit. The body 



FIG. 165. Locust from lateral aspect (left wings f ' 



removed), showing (ao.) auditory organ, is rather robust, the head is set 

 (Natural size.) w j t h j ts i ong axis at rignt ang i es 



with the axis of the body, so that the mouth with its strong biting and 

 crushing jaws is directed downwards (Fig. 165) ; the antenna? are never 

 as long as the body and are composed of not more than twenty-five 

 segments; the prothorax is covered laterally as well as dorsally by its large 

 saddle-like horny pronotum, which projects so as also to cover and protect 

 from the sharp grass-blades the soft thin-walled neck and the equally 

 thin- walled suture between prothorax and mesothorax; the abdomen is 

 broadly and closely joined to the metathorax, and 

 in the female ends in a short and strong ovipositor 

 composed of four horny pointed pieces; the hind 

 legs are much larger than the others and fitted 

 for leaping, and the fore wings, called tegmina, 

 are narrow and straight-margined, and serve 

 specially to cover and protect the much larger 

 thin membranous hind wings, which are plaited 

 and folded like a fan when the locust is at rest. 



The sounds or stridulation of locusts are 

 made in two ways. When at rest certain species 

 draw the hind legs up and down across the wing- 

 covers so that numerous fine little ridges on the 



inner surface of the broad femora are rasped FlG ^.-Locuslimpaled on 

 across a thickened and ridged longitudinal vein thorn by shrike (butcher- 

 on the outer surface of the wing-covers. When bird)< ( Natural size -) 

 in flight certain locusts rub or strike together the upper surface of the 

 front edge of the hind wings and the under surface of the fore wings 

 or tegmina. This produces a loud, sharp clacking which can be heard 

 for a distance of several rods. The loudest "clacking" of this kind 



