THE GRASSHOPPER 



into the solid capsule of the cranium. Thus we see that 

 the entire body of an insect is composed of a series of seg- 

 ments which have become grouped into the three body 

 regions. Note that the insect does not have a 

 "nose" or any breathing apertures on its head. 

 It has, however, many nostrils, called spiracles 

 (Fig. 70, Sp), distributed along each side of 

 the thorax and the abdomen. Its breathing 

 system is quite different from ours, but will 

 be described in another chapter treating of 

 the internal organization (page 1 14). 



Most young insects grow rapidly be- 

 cause they must compress their entire 

 lives within the limits of a 

 single season. Generally a few \V 

 weeks suffice for them to reach 

 maturity, or at least the ma- 

 ture growth of the form in 

 which they leave the egg, for, 

 as we shall see, many in- 

 sects complicate their lives 

 by having several different 

 stages, in each of which 

 they present quite a dif- 

 ferent form. The grass- 

 hopper, however, is an in- 

 sect that grows by 

 a direct course from 

 its form at hatch- 

 ing to that of the 

 adult, and at all 

 stages it is recog- 

 nizable as a grass- 

 hopper (Fig. 9). A 

 young moth, on 

 the other hand, 

 hatching in the 



Fig. 9. The metamorphosis of a grasshopper, 

 Melanoplus atlanus, showing its six stages of develop- 

 ment from the newly-hatched nymph to the fully- 

 winged adult. (Twice natural size) 



13 



