leptim:. 



161 



turned backward. On the fifth segment below there is a 

 simple unpaired grasping foot which is capable of being 

 protruded forward and downward; at its tip there are 

 two triangular, sharp, flat, chitinous hooks, and below 

 them some stiff bristles. The hooklets serve as aids in 

 boring in the sand and to fix themselves; the organ on 

 the fifth segment assists the larva in seizing and holding 

 its prey, and also in constructing the pitfalls. 



2.™ A Z../|5tt. .wuxi<li"t*y 



Fig. 54. Leptidse. 18, Arthroceras (type) , wing; 19, Arthroceras 



(type), antenna; 20, Rhachicerus, head; 21, Atherix, venation. 



