THE ANT-LION 209 



Cicindela uses the excavation just described for the 

 purpose of a trap or pitfall, any further than that it 

 can more effectually secure its prey by tumbling them 

 down into it; but there are other species of grubs 

 which construct pitfalls for the express purpose of 

 traps. Among these is the larva of a fly {Rhagio 

 vermileo), not unlike the common flesh maggot. 

 The den which it constructs is in the form of a 

 funnel, the sides of which are composed of sand or 

 loose earth. It forms this pitfall of considerable 

 depth, by throwing out the earth obliquely on all 

 sides; and when its trap is finished, it stretches it- 

 self along the bottom, remaining stiff and motionless, 

 like a piece of wood. The last segment of the body 

 is bent at an angle with the rest, so as to form a 

 strong point of support in the struggles which it must 

 often have to encounter with vigorous prey. The 

 instant that an insect tumbles into the pitfall, the 

 grub pounces upon it, w^reathes itself round it like a 

 serpent, transfixes it with its jaws, and sucks its 

 juices at its ease. Should the prey by any chance 

 escape, the grub hurls after it jets of sand and earth, 

 with astonishing rapidity and force, and not unfre- 

 quently succeeds in again precipitating it to the 

 bottom of its trap. 



The Ant-Lion. 



The observations of the continental naturalists 

 have made known to us a pitfall constructed by an 

 insect, the details of whose operations are exceed- 

 inf^ly curious — we refer to the grub of the ant-lion 

 {Mijrmeleon formicarius) , which, though marked by 

 I)r Turton and Mr Stewart as British, has not (at 

 least of late years) been found in this country. As 

 it is not, however, uncommon in France and Swit- 



VOL. IV. 18* 



