NF.UROPTERA. 



183 



of these larvae, and place them in a basin of sand, and 

 watch them build their pits. They do this by using the head 

 for a shovel. Sometimes when an ant seems likely to escape, 

 the Ant-lion will throw up a torrent of sand so that it will 

 descend on the victim, knocking it back into the pit. 



When ready to change to a pupa the Ant-lion makes for 

 itself a little, round cocoon of sand fastened together and lined 

 with silk. The adult Ant-lion is a graceful insect with long, 

 narrow, delicate wings, and a slender body (Fig. 222). 



Fig. 222.— Larva, cocoon with pupa-skin projecting, and adult of an Ant-lion. 



Certain members of this family differ from the ant-lions 

 in having long, filiform antennae, which are suddenly en- 

 larged at the end. These belong to the genus Ascalaphiu 

 (As-eal'a-phus). 



