ANT-LIONS 



the way in which a Myrmeleon larva got rid of pebbles 

 too large to be moved from its pit by tossing with the 

 head. The correctness of this statement was question- 

 ed, and I therefore put it to the test. Three pebbles, 

 all larger and heavier than the larva, were dropped into 

 the centre of a pit where they would be most incon- 

 venient to the occupant, and likely to prompt her to 

 remove them. The experiment succeeded perfectly. 



The ant-lion thrust its head beneath a pebble and 

 tried to toss it from the pit. Having failed in this, it 

 tried another mode. It placed the end of its abdomen 

 against and a little beneath a pebble, and began to push 

 backward. A little time was taken to adjust the pebble 

 so that its centre of gravity would be against the end of 

 the body. Then the animal began to back out of the 

 pit, pushing the pebble before, or rather behind it, up 

 the side, and to a point a short way beyond the margin, 

 where it was left. A small furrow was thus made in 

 the sand, curved from the point of departure up the 

 wall of the pitfall. The pebble was kept perfectly bal- 

 anced during the entire movement, which was quite 

 rapid and made with the ease and assurance as well as 

 the celerity of an expert. All of the three pebbles were 

 thus removed; and the experiment was repeated a 

 number of times, always with the same result. 



Some well-rounded bits were now dropped into the 

 sand in order to increase the difficulty of balancing the 

 load; but this made no difference in the larva's action. 

 A round pebble was balanced and removed quite as 

 readily as any other. That this task required no little 

 acrobatic skill I satisfied myself by sundry experiments. 

 My deftest efforts to push a pebble before the point of 

 a pencil, a la Myrmeleon, were not an eminent success. 



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