374 



IXJUKIOUS INSECTS 



then travel during the warmer hours of the day by alter- 

 nately walking and hopping in vast bodies in some given 

 direction. In thus travelling they move at the average 

 rate of about three yards a minute. There are six stages 



Fig. 160. THE LABV^J AND PUPA OF LOCUST, 

 a, a, Newly-hatched Larvae ; b, Full-grown Larva , c, Pupa of the Locust. 



of growth, i. e., the locust moults at five different periods. 

 The change at each of these moults is but slight, and the 

 wing-pads are first distinctly noticeable and turned up in 



a. 



Fig. 161. THE PUPA OP THE LOCUST ACQUIRING WINGS. 



a, Papa with skin just split on the back ; &, the imago extruding ; c, the imago near- 

 ly out ; d, the imago with wings expanded. 



the fourth stage, or after the third moult. After the 

 fourth moult we have the true pupa stage (fig. 160, c), 

 and with the fifth moult the wings are acquired, the pro- 

 cess being illustrated at figure 161. The time required 



