1879.] NATURAL SCIENCES OF PHILADELPHIA. 141 



located directty in and on the grassy border of a trodden path in 

 a farmyard. At 4 P. M the males and females were seen coming 

 out and re-entering the gate, amid great excitement on the part of 

 the workers. The females particularly were followed by workers 

 who " teased" them occasionally by gentty nipping them with their 

 mandibles. The flight of the young queens was, with few excep- 

 tions, made from the top of stalks of grass, where they clung for 

 several minutes, poising themselves, spreading their wings, and 

 swaying up and down. Even to these elevations the workers fol- 

 lowed them, hastening their flight by occasional "nips." When 

 the queen rose in flight, there was no evidence of feebleness or 

 inexperience, except, in some cases, a slight tendency to a zig-zag 

 course for the first few yards. The flight was then, and in most 

 cases from the very first also, strong and in a straight course. The 

 insect first rose to a height of about 20 feet, which was soon in- 

 creased to 40, 50, and even 60 feet (estimated), and this latter 

 height was maintained until the form was lost to sight. lie was 

 able to follow the ants in several instances to a distance of more 

 than 300 feet, before they disappeared, at which time the} 7 gave 

 no sign of alighting. Some were seen to alight at the distance of 

 60 and 80 feet; others flew into a large buttonwood tree within 

 30 feet of the nest. 



The flight was in every case solitary, and was in all directions, 

 although generally in the direction of the breeze. The males 

 were in the mean time continually taking flight, urged thereto by 

 teasing workers, each separately, and wholly independent of other 

 males and of the females, as to the time and direction of flight. 

 This fact led Mr. McCook to infer that the pairing of the sexes 

 must have occurred within the nest before departure therefrom. 

 Except in the case of those individuals who lit upon the button- 

 wood tree, there appeared no opportunity for a meeting after 

 flight. There was nothing in all the facts to suggest the idea of 

 a future consort. The same feature of independent and solitary 

 flight of the sexes had been observed in the swarming of the Shin- 

 ing Slave-maker Polyergus lucidus. This is in marked contrast 

 with the habit of some other ants as illustrated in an observation 

 subsequently given. 



Before taking flight the L. flavus females spent some time in 

 combing and cleansing themselves. A female was placed among 

 the workers of another nest not more than a yard distant from her 

 own, in order to test the treatment of an alien. She was immedi- 

 ately attacked fiercely, and would no doubt have been soon killed 

 had she not been removed. In two formicaries from which the 

 above marriage-flight occurred, it was observed that the doors 

 were closed about 4i P. M. b} r bits of dry grass and pellets of soil. 

 They so remained during the night, -or at least were found closed 

 in the morning. Three days thereafter several males were found 

 nestled under a chip by the roadside. As soon as the chip was 



