50 
Psyche 
[March 
not begin to move away from the structure until male flight had been 
going on for from 5 to 20 minutes. The females came out singly, 
and there were never many in sight at one time (1-9)* A. female 
would emerge, walk or run on the ground near the nest area, and 
climb up and down grasses, sometimes standing for a long time on 
a grass tip. After several minutes of this, she would climb a grass 
stem, flutter her wings, and fly. Often the first take-off was not 
successful ; she would drop to a neighboring grass, and the wandering 
would begin again. This more leisurely action on the part of females 
sometimes prolonged flights for as much as eight to 28 minutes after 
all males had flown. The Lawn Colony did not produce many fe- 
males; 58 were counted in three flights in 1961 and 17 in six flights in 
1962. On these nine flights the time of flying of the first female was 
delayed beyond that of the first male by 16 to 51 minutes, with a 
mean of 36 minutes. The delay on the part of the females could 
not be accounted for on the basis of changes in temperature or light 
since the mean starting temperature and light for males were 83.3°F 
and 7,478 ft-c while for females they were 83.5°F and 7,288 ft-c. 
Workers played only a moderate role in flights. Polyerg, us workers 
did not react to the alates in any way and only occasionally did one 
come to the surface, to retreat again soon or to move out into the 
grasses. F. p. nitidiventris workers enlarged entrances at the begin- 
ning of the flight season and reopened them after rains. During good 
flying weather they foraged busily, paying no attention to the alates. 
But sometimes at the start of a flight a group of 10 to 20 workers 
would follow the first males up onto grasses and try to get them to 
turn back, or they would hunt for stragglers at the end of a flight. 
Occasionally, under adverse conditions, such as lessening light or 
very high ground temperatures, they would become active in the mid- 
dle of a flight. Males were often carried down grasses into the nest. 
The larger females were sometimes carried, but more often they were 
simply nudged until they retreated. 
Colony founding. Once a female has mated and discarded her 
wings, her next problem is to locate a Formica pallidefulva nitidiven- 
tris colony which she can invade. One method by which young, 
dealate females find such colonies was discovered while raids were 
being watched at the 0-26 and the Lawn Nests. On 15 different 
days, during flight seasons, one or two dealate females were seen 
hanging about a Polyergus nest during the afternoon. The females 
circled in the grasses and frequently cut across the nest area. Polyer- 
gus workers, running about in preraid activity, were hostile and 
