INTELLIGENCE OF ANTS. 495 



INTELLIGENCE OF ANTS. 



By GEOKGE J. EOMANES. 



I HAVE frequently been much struck by the absence of informa- 

 tion, even among professed naturalists and professed psycholo- 

 gists, concerning the intelligence of ants. The literature on the subject 

 being scattered and diffused, it is not many persons who have either 

 the leisure or the inclination to search it out for themselves. Most of 

 us, therefore, either rest in a general hazy belief that ants are wonder- 

 fully intelligent animals, without knowing exactly in what ways and 

 degrees the intelligent action of these animals is displayed ; or else, 

 having read Sir John Lubbock's investigations, we come to the general 

 conclusion that ants are not really such very intelligent animals, after 

 all, but, as was to have been expected from their small size and low 

 position in the zoological scale, it only required some such methodical 

 course of scientific investigation to show that previous ideas upon the 

 subject were exaggerated, and that, when properly tested, ants are 

 found to be rather stupid than otherwise. I have therefore thought it 

 well to write a paper for this widely circulated review, in order to 

 diffuse some precise information concerning the facts of this interest- 

 ing branch of natural history. 



Not having any observations of my own to communicate, I have no 

 special right to be heard on this subject ; but, as I have recently had 

 occasion to read through the literature connected with it, I am able to 

 render what I may call a filtered abstract of all the facts which have 

 hitherto been observed by others. It is needful, however, to add that 

 the filter has been necessarily a close one ; if I had a large volume in- 

 stead of a short paper as my containing vessel, the filtrate would still 

 require to be a strongly condensed substance. 



Powers of Special Sense. Let us take first the sense of sight. 

 Sir John Lubbock made a number of experiments on the influence of 

 light colored by passing through various tints of stained glass, with 

 the following results : 1. The ants which he observed greatly disliked 

 the presence of light within their nests, *' hurrying about in search of 

 the darkest corners " when light was admitted. 2. Some colors were 

 much more distasteful to them than others ; for while under a slip of 

 red glass there were on one occasion congregated 890 ants, under a 

 green slip there were 544, under a yellow 495, and under a violet only 

 5. 3. The rays thus act on these ants in a graduated series, which 

 corresponds with the order of their influence on a photographic plate. 

 Experiments were therefore made to test the effect of the rays on either 

 side of the visible spectrum, but with negative results. In considering 

 these experiments, however, it is important to remember that other ob- 

 servers (especially Moggridge in Europe, and McCook in America) have 



