4 ANIMAL BIOLOGY 



smaller accessory jaws, the first maxilla and (3) the la- 

 bium or lower lip, which is composed of the second max- 

 illa more or less fused together. The peculiar working of 

 these organs may be readily seen in a living specimen. 

 The thorax, or the part of the body immediately behind 

 the head, consists of three segments called the prothorax, 

 mesothorax and metathorax in order from be- 

 fore backward. Like nearly all insects the 

 grasshopper has six legs, a single pair being 

 attached to each segment of the thorax. 

 The first two pairs which are fitted for walk- 

 ing or climbing are quite different from the 

 last pair which is mainly used for jumping. 

 It may readily be seen that the parts of the 

 legs are united by flexible membranes at the 

 joints so as to permit of free movement. 

 Each leg consists of two short segments near 

 the base, a relatively large part, the femur, 

 followed by the tibia, and finally the foot, 

 or tarsus. The latter ends in a pair of claws 

 and is furnished wih pads below the segments. 

 The hind legs are especially noticeable on 

 Mouth 'parts~of account of their large size and the double 

 grasshopper. row o f s harp spines on the posterior side of 



m, mandible; 



max, maxilla; /. the tibia. The function of these spines may 

 ^abmm; p, pal- rea( ^jjy b e discovered by observing live grass- 

 hoppers. 



The first pair of wings which are situated on the meso- 

 thorax are often called the wing covers as they lie over the 

 large second pair of wings which are the chief organs of 

 flight. The first wings are narrow, relatively thick and 

 usually of a dull color. The second pair are broad, 

 thin of texture and frequently brightly colored. Ordina- 

 rily the latter are not seen except during flight as they lie 



