172 INJURIOUS AND USEFUL INSECTS 



suddenly extended like an arm. At the angles of the broad 

 end there are sharp, curved claws, which bend inwards and 

 impale a victim. The sluggish, dull-coloured larva lurks in 

 some weedy recess, marks the approach of a moving animal, 

 and then, moving the body little or not at all, stretches out 

 the labium, which strikes but once to secure the prey. The 



Fig. go. — A, dragon-fly larva (j^schna), with rudiments of wings ; B, head of 

 do., seen from beneath; C, mandible; D, maxilla; E, mouth-pavts after 

 removal of most of the labium ; F, fore edge of labium. 



thorax, as seen from above, presents a pair of side-pieces, from 

 beneath which, in the older larvas, two pairs of wings protrude. 

 These are not themselves the wings that will serve for flight, 

 but rather wing-cases, within which the future wings are grow- 

 ing, or, if already grown, lie crumpled up. The legs are long 

 and many-jointed, but they are not very actively employed; 

 the larva uses them more for support than for locomotion. 

 The segmented abdomen is generally stout, but in the larvae 



