166 ORTHOPTERA. 



bly act in some measure to increase the reverberation of the 

 sound, like the cavity of a violin. When a locust begins to 

 play, he bends the shank of one hind leg beneath the thigh, 

 where it is lodged in a furrow designed to receive it, and 

 then draws the leg briskly up and down several times against 

 the projecting lateral edge and veins of the wing-cover. 

 He does not play both fiddles together, but alternately, for a 

 little time, first upon one, and then on the other, standing 

 meanwhile upon the four anterior legs and the hind leg 

 which is not otherwise employed. It is stated that, in Spain, 

 people of fashion keep these insects, which they call grillo, in 

 cages, for the sake of their music. 



Locusts leap much better than grasshoppers, for the thighs 

 of their hind legs, though shorter, are much thicker, and 

 consequently more muscular within. The back part of the 

 shanks of these legs, from a little below the knee to the end, 

 is armed with strong sharp spines, arranged in two rows. 

 These may serve as means of defence, but the lower ones also 

 help to fix the legs firmly against the ground when the insect 

 is going to leap. The power of flight in locusts is, in general, 

 much greater than that of grasshoppers ; for the wing-covers, 

 being narrow, do not, like the much wider ones of grass- 

 hoppers, so much impede their passage through the air ; while 

 their wings, which are ample, except in a few species, and 

 when expanded together form half of a circle, have very 

 strong joints, and are moved by very powerful muscles within 

 the chest. From the shoulders of the wings several stout ribs 



o 



or veins pass towards the hinder margin, spreading apart, 

 when the wings are opened, like the sticks of a fan, and are 

 connected and strengthened by little crossing veins, which 

 form a kind of network. The same structure exists in the 

 wings of grasshoppers, but in them the longitudinal ribs are 

 not so strong, and the network is much more delicate. Hence 

 the flight of grasshoppers is short and unsteady, while that of 

 locusts is longer- and better sustained. Many locusts, when 

 they fly, make a loud whizzing noise, the source of which does 



