126 NATURAL HISTORY OF INSECTS. 



LACE-WINGED FLIES (Hemerobida? ) . The 'insects belonging 

 to this Family have four wings of nearly equal size ; the 

 antennae are long, and the feet are five-jointed; transforma- 

 tions complete. The larvae are usually terrestrial. This 

 Family contains many beneficial insects ; prominent among 

 which are the Lace- winged (Tig. 21) and the Golden-eyed Flies, 

 the larvae of which (Fig. 47 J feed upon Plant-lice ; when fully 

 grown each of these larvae spins a globular cocoon, inside of 

 which it assumes the pupa form ; when the perfect insect is 

 nearly ready to emerge, the pupa issues from the cocoon and 

 fastens itself to a neighboring object by its feet ; in a short 

 time the skin on its back is rent, and the perfect insect makes 

 its escape. Another member of this Family is the Ant-lion, 

 the larvae of which excavate funnel-shaped holes in the earth 

 in which to entrap their prey, which consists principally of 

 ants. 



SCORPION-FLIES (Panorpidae). These insects are usually 

 provided with four wings of equal size, but in a few species 

 the wings are rudimentary or wanting ; the antennae are con- 

 spicuous, and the feet are five-jointed ; transformations com- 

 plete ; the mouth-parts are produced somewhat in the form of 

 a beak. The larvae are generally terrestrial, and are probably 

 predaceous. 



CADDIS-FLIES (Phryganidae). These insects have four wings, 

 in which the transverse veins are not numerous ; the antennae 

 are quite long, and the feet are five*jointed ; the mouth-parts 

 are not distinct ; transformations complete. The larvae are 

 usually aquatic, living in silken tubes, to which they frequently 

 attach small shells, pieces of wood, and other small objects. 

 They feed upon vegetable matter, and sometimes devour small 

 insects. 



