HABITS AND STRUCTURE OF INSECTS. 99 



teen year locust as it is improperly called, has an interesting 

 life-history. 



The perfect insect is shown in Fig. 95. They may be 

 known by the peculiar loud, buzzing sound emitted by the 

 male. This sound can oftentimes be heard at a great dis- 

 tance. 



FIG. 95. SEVENTEEN- YBAB CICADA. 



The seventeen-year cicada is found rarely in Southern 

 New England, but is common in the Southern and Western 

 States. This species exists in great numbers, and does 

 immense damage to the trees which it infests. The female 

 deposits her eggs in the twigs and smaller branches of 

 oaks. Little furrows are made in the twig, side by side, and 

 within these furrows the eggs are laid. The leaves wither 

 on the trees from the injuries inflicted in this way. Lit- 

 tle insects hatch from the eggs, entirely different in appear- 

 ance from the parent ; and these, running to the end of the 

 twig, fling themselves off, and falling to the ground dig 

 their way down, till they come to some root upon which 

 they fasten, and with a piercing sting suck the juices of 

 the root. Here they remain for nearly seventeen years, 

 slowly growing. At the end of that time they assume the 



