346 
Psyche 
[December 
0 8 20 46 min 
Fig. 9. Mass-recruitment experiment in a large colony. The back-and- 
forth passages of ants were counted in periods of 2 min at 3 different 
places: On the main bridge between nest and the side turn (A) and the 
“garden” (old feeding station) (B) and third on the food bridge (C). The 
food bridge was connected after 8 min. The alerting stimuli predominantly 
affect increase in running activity on the old trail (B) during the first 
period. Only after 20 min (dashed line) relatively more ants turn towards 
the food (C). This means that the alerting stimulus alone gives no informa- 
tion about the location of the food. 
