172 



NEUROPTERA. 



are used by the mature larva for breathing air when it 

 leaves the water, before making a cavity or cell in the 

 earth in which to pupate. The pupa (Fig. 119,^) 

 remains inactive for about a month, and has neither 

 mouth nor anus. During this period of immobility 

 very great structural changes go on, which fit the 

 water-insect for an aerial life in much less time than 

 would be possible were the insect active. 



HEMEROBID.E. 



The lace-winged fly, Chrysopa (Fig. 120, a), is a 

 beautiful insect, though its odor is disagreeable. The 

 head is dumb-bell-shaped, with brilliant golden-col- 



^ 



K?^ 



O 



Fig. 120. 



ored eyes projecting on either side. The plan of 

 structure observable in the thorax is exactly reversed 

 from that of the dragon-fly. The markings in the last 

 two thoracic rings extend downward and backward, 

 and the legs are carried backward instead of forward. 

 The wings, though large, are extremely delicate, and 

 the flight is weak. 



According to Comstock, the female before laying 



