COMPARATIVE ZOOLOGY. 



Pia. 265. Metamorphosis of an Hemipter, Water-boatman (NotonecM). 



vse and pupae are active, and resemble the imago. They 

 are nearly all vegetarian. Each family produces charac- 

 teristic sounds (stridulation). The representative forms 



Fia. 266 Seventeen-year Cicada (Cicada eptendecim) : a, pupa; 6, the pame, after 

 the imago, c, has escaped through a rent in the back ; d, holes in a twig, where 

 the eggs, e, are inserted. 



