COMMUNICATING AND OTHER ANTS 67 



is a difficult operation. The workers are so tiny, so 

 agile and quick in their movements, so excited and 

 easily frightened that the slightest touch fills them 

 with alarm. At last after many days and innumer- 

 able unsuccessful attempts, I succeeded in marking 

 three ants without terrifying them out of their 

 senses. I found that the worker returning with the 

 news of the discovery emerged from the nest, not 

 at the head of the issuing throng as though it was 

 acting as a leader, but appeared in the midst of the 

 swarm. Nor was it essential as a guide to the true 

 road which led to the discovery, for many of the ants 

 in the issuing swarm outran it and came first to the 

 treasure. Undoubtedly its presence in the swarm was 

 a great assistance, for many of the ants would rush up 

 to the marked ant, rub their antennae against it and 

 then hasten off to the insect in the greatest excitement 

 as though they had gained valuable information by 

 contact with the discoverer. But it is certain that the 

 discovering ant, once it has given information, is no 

 longer essential as a guide to the swarm, for I 

 captured one of the marked ants at the moment of its 

 emergence from the nest, and the swarm, in its 

 absence, had no difficulty in finding the insect. 



Since the returning ant cannot act solely as a guide 

 and since, indeed, its presence seems to be no longer 

 essential once it has passed its information to the 

 awaiting throng, it was difficult to form any other 

 conclusion but that the issuing ants found their way 

 to the treasure by retracing the scent of the returning 

 ant. 



I think that this can be the only explanation, for 

 when the swarm is hurrying to the discovery it 



