BEHAVIOR OF THE ANT-LION. 303 



its mandibles being amputated. The tonic contraction of the 

 muscles and the diminished reflex irritability suggest hypnotic 

 phenomena and lead one to agree with Holmes (31) that "the 

 instinct of feigning death is doubtless connected with much of 

 what has been called hypnotism in the lower animals." It is 

 well known that most animals pause momentarily when con- 

 fronted with an unexpected or violent stimulus. To me the 

 letisimulation of the ant-lion appears to be such a pause pro- 

 longed and exaggerated. The more I ponder over the results of 

 my experiments upon the death-feigning of the ant-lion, the more 

 I feel inclined to exclaim with James: "It really is no feigning of 

 death at all and requires no self-command. It is simply terror 

 paralysis which has been so useful as to become hereditary." 



CONCLUSIONS. 



1 . The pits of the ant-lion are not confined to sand ; they may 

 be found in any kind of dry friable soil, that is protected from 

 the rain and from insect-eating creatures. They are usually in 

 clusters; but, occasionally, a solitary pit is found. On yet rarer 

 occasions, pits may be found that are not under a shelter. 



2. The ant-lion of the Middle West has two methods of ex- 

 cavating its pits. Usually it furrows backward, excavating a 

 series of concentric, adjacent circles, each deeper than the last, 

 and shovelling out the soil with its head. The front of the body 

 is so curved as to make it easy for the dirt to fall forward on the 

 head. In the second method, the larva simply burrows downward 

 into the ground and tosses out the soil with its head until the 

 sides of the pit become approximately stable. Pits formed by 

 the second method are usually subsequently enlarged. 



3. The ant-lion removes a medium sized obstacle from its pit 

 by inserting the tip of its abdomen under it and, with the burden 

 poised on its abdomen, backing slowly up the slope. 



4. After its trap has been completed, the ant-lion rests quietly, 

 in practically a horizontal position, with its body beneath the 

 soil and its open mandibles in the bottom of the pit. 



5. Any invertebrate, be it insect, arachnid, or crustacean, that 

 happens to fall into the trap is acceptable food. Some escape, 

 but the larva attempts to capture all. When captured, the 



