498 THE POPULAR SCIENCE MONTHLY, 



To turn back these stragglers and keep them out of sight for a number of 

 days, sometimes for a fortnight, it is sufficient to kill one or two ants on the 

 trail. . . . The moment the spot is reached an ant turns abruptly and makes 

 for home, and in a little while there is not an ant visible on the wall. 



Many other cases might be quoted to show that ants are able to 

 communicate information to one another ; but, to save space, I shall 

 pass on to Sir John Lubbock's direct experiments upon this subject. 

 Three similar and parallel tapes were stretched from an ant's nest to 

 three similar glass vessels. In one of the latter Sir John placed 

 several hundred larvse, in another only two or three larvae, and the third 

 he left empty. The object of the empty glass was to see whether any 

 ants might not run along the tapes without any special reference to 

 the obtaining of larvae ; and this was found not to be the case. Sir 

 John then put an ant to each of the other two glasses ; they each 

 took a larva, carried it to the nest, returned for another, and so on. 

 Each time a larva was taken out of the glass containing only two or 

 three, Sir John replaced it with another, so that the supply should not 

 become exhausted. Lastly, every ant (except the two which had first 

 been put to the larvie), before reaching home with her burden, was 

 caught and imprisoned till the observation terminated. 



The result was, that during forty-seven and a half hours the ants 

 which had access to the glass containing numerous larvae brought 257 

 friends to their assistance ; while during an interval of five and a half 

 hours longer those which visited the glass with only two or three 

 larvae brought only 82 friends. This result appears very conclusive as 

 proving some power of definite communication, not only as to where 

 food is to be found, but also as to the road which leads to the largest 

 store. Further experiments, however, proved that these ants are not 

 able to describe the precise locality where treasure is to be found. 

 For, having exposed larvae as before and placed an ant upon them, he 

 watched every time that she came out of the nest with friends to assist 

 her ; but, instead of allowing her to pilot the way, he took her up and 

 carried her to the larvae, allowing her to return with a larva upon her 

 own feet. Under these circumstances the friends, although evidently 

 coming out with the intention of finding some treasure, were never 

 able to find it, but wandered about in various directions for a while, 

 and then returned to the nest. Thus, during two hours, she brought 

 out altogether in her successive journeys no less than 120 ants, of 

 which number only five in their unguided wanderings happened by 

 chance to find the sought-for treasure. 



Memory. The general fact that, whenever an ant finds her way to 

 a store of food or larvae, she will return to it again and again in a 

 more or less direct line from her nest, constitutes ample proof that the 

 ant remembers her way to the store of food. It is of interest to note 

 that the nature of this insect-memory appears to be identical with that 

 of memory in general. Thus, a new fact becomes impressed upon ant- 



