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AN INTRODUCTION TO ENTOMOLOGY 



Ant-lions are much more common in the Southern and Southwest- 

 em States than they are in the North. The pitfalls of the larvae are 

 usually found in sandy places that are protected from rain, as beneath 

 buildings or overhanging rocks. In making these pitfalls the sand 

 is thrown out by an upward jerk of the head, this part of the body 



Fig. 344. — Wings of Myrmeleon. 



serving as a shovel. The pits differ greatly in depth, according to the 

 nature of the soil in which they are made. Their sides are as steep 

 as the sand will lie. When an ant or other wingless insect steps upon 

 the brink of one of these pits, the sand crumbles beneath its feet, 

 and it is precipitated into the jaws of the ant-lion, which is buried 

 in the sand, with its jaws at the bottom of the pit (Fig. 345). Incase 

 the ant does not fall to the bottom of the pit, the ant-lion undermines 

 it by throwing out some sand beneath it. I have even seen an ant-lion 

 throw the sand in such a way that in falling it would tend to hit the 

 ant and knock it down the side of the pit. These larva can be easily 

 kept in a dish of sand, and their habits watched. 



The most common ant-lion 

 in the North is Myrmeleon ini- 

 maculdtus; the larva of this 

 species makes a pitfall. The 

 habits of the larvae of Glenunis, 

 Dendroleon, and Acanthdclists, 

 three genera that are repre- 

 sented in this country, have 

 been described by European 

 writers. These larvas do not 

 dig pitfalls, but partially bury themselves in the sand, from which 

 position they throw themselves quickly upon their victims. 



345. — Pitfall of an ant-lion. 



