192 



NATURAL HISTORY 



The horned corydalus is one of the most formidable-looking of insects, 

 the strong jaws, especially developed in the male, giving them a most 

 ferocious appearance. In reality they are harmless, and the long jaws of 



Fig. 177. — Female of the horned corydalus {Corydalus cornutus). 



\-M>$ 



the male are utterly incapable of biting, but are only used for seizing the 

 body of the female during the act of pairing. Like so many others of the 



forms under discussion, the larva of the corydalus ia 

 aquatic, and is well known as the favorite bait of 

 fishermen, — the hellgrammite. In the larval state 

 it occurs abundantly in rivers and ponds of the north- 

 ern states, and there devours an immense amount of 

 small aquatic worms and larval insects, and thus does 

 a deal of good. 



Closely allied to these last are the ant-lions, most 

 interesting in their larval stages. In Europe they 

 are very abundant, but in our country they seem to 

 be more local. The largest colony ever seen by the 

 writer was in the sand in one of the many pictur- 

 esque gorges at Ithaca, N.Y., although even larger 

 ones have been noticed. The larval ant-lion marks 

 out a circle some two inches in diameter in the sand, 

 and then throws out all the sand inside this circle 

 with its jaws. The flirt they give is so strong that 

 the sand is thrown some five or six inches, and thus 

 there is no ridge around the edge of the pit. Little 

 fig. 178. — Hellgrammite, the by little the excavation goes on, until at last the 



larva of the honied cory- v .. -. , .,. ' P _., ,. 



daius. limit ol stability is reached. The ant-lion can dig no 



