Mating 61 



pouncing on some female winging toward him, unit- 

 ing on the under side, and permitting himself to be 

 carried by her in a slow flight for a few seconds, then 

 separating. One male will mate with several females 

 in succession when thus unconfined. I have noted 

 that, early in the morning, these insects had a habit 

 of coming in pairs when they alighted upon me. 



The mating of the marsh species evidently takes 

 place during the evening swarmings, when little or 

 no wind is blowing. The act in these forms, from 

 accounts given, apparently lasts but a short time. 



As for pipicns mating, I have noticed them in 

 swarms about sundown in the autumn, from five to 

 eight feet from the ground, the female flying into 

 the swarm, which was composed of males, leaving 

 at once, united with a male, flying with him for a 

 short distance, then abandoning him and seeking a 

 shelter. Mr. Knab gives a good and detailed account 

 of the swarming and mating of pipiens observed by 

 him on the evenings of October 15 to 18, 1904, 

 at Urbana, 111. The first three evenings were warm, 

 with no perceptible breeze, but the drift of smoke 

 showed a light air current. The insects, at about 

 5 o'clock, were found dancing in swarms composed 

 entirely of males, above all the corn-stooks in a 

 field near a stream, and over trees, shrubbery, etc., 

 all facing in the direction of the air current, and 

 being on the opposite side of the corn-stook to 

 that from which the breeze came. 



On the fourth evening a breeze induced the 

 swarms to form to leeward of projecting objects, 

 causing more or less confusion. It was noted that 



