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NATURAL HISTORY OF ARTHROPODS. 



While the ant-lion's pit found by Mr. Emerton was a solitai-y one, no others being 

 found, Mr. Birge records his discovery of a large colony of ant-lions in a sheltered, 

 sandy place, under a cliff, in Albany County, New York. In August, 1871, the colony 

 numbered rather more than six hundred individuals, but on July 6, 1872, there were 

 scarcely half that number. Another colony, at a different locality, but in the same 

 county, observed in 1871, consisted of some three hundred members. Mr. Birge 

 remarked that the ant-lion did not, so far as his observation went, " throw up sand to 

 bring down its prey, but throws it up in every direction in order to keep its jaws free 



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FIG. 234. Nemoptent coa ami Ascalaphus Jongicarnis. 



to seize the insect when it reaches the bottom of the den." Further on he says, in the 

 most crowded portions of the colony " the chief employment of the insects was to throw 

 out the dirt which their active neighbors were depositing on their own premises." 



In JVemoptera coa, a species from the Mediterranean region of Europe, the fore- 

 wings are very broad, while the hinder ones are greatly elongate, so that they suggest 

 a pair of oars. 



The last type of this family is Ascalaphus, which superficially bears a resemblance 

 to a butterfly, since the long, slender antenna? end in a conspicuous knob. The head 

 is large and hairy, with large, round eyes, the large wings are often highly tinted with 

 yellow and black spots and bands, while the abdomen is short and thick, like that of 



