126 ANIMAL INTELLIGENCE. 



(pp. 241-2). But even this consideration does not ex- 

 tenuate the stupidity of the ants which failed to heap up 

 the fine earth to reach the glass cell which they were able 

 to touch with their antennae. 



That the species of ants on which Sir John Lubbock 

 experimented were not, however, quite destitute of intel- 

 ligence is proved by the result of the following experi- 

 ment : 



I put some provisions in a shallow box with a glass top and 

 a single hole in one side ; I then put some specimens of Lasius 

 niger to the food, and soon a stream of ants was at work busily 

 carrying supplies off to the nest. When they had got to know 

 their way thoroughly, and from thirty to forty were so occupied, 

 I poured some fine mould in front of the hole, so as to cover it 

 to a depth of about ^ an inch. I then took out the ants which 

 were actually in the box. As soon as the ants had recovered 

 from the shock of this unexpected proceeding on my part, they 

 began to run all round and about the box, looking for some 

 other place of entrance. Finding none, however, they began 

 digging down into the earth just over the hole, carrying off the 

 grains of earth one by one and depositing them without any 

 order all round at a distance of from ^ to 6 inches, until they 

 had excavated down to the doorway, when they again began 

 carrying off the food as before. 



This experiment was several times repeated on L. niger 

 and on L.flavus, always with the same result. 



Thus, then, we may conclude that the reasoning power 

 of these ants, although shown by the first experiments to 

 be almost nil, is shown by this experiment to be not quite 

 nil ; for the attempt to meet the exigencies of the case 

 by first going round the box to seek another entrance, 

 before taking the labour to remove the earth from the 

 known entrance, implies a certain rudimentary degree of 

 adaptive capacity which belongs to the category of the 

 rational. 



Another point of considerable interest, as bearing on 

 the general intelligence of ants, is one that was brought 

 out as the result of a laborious series of hourly observa- 

 tions, extending without intermission from 6.30 A.M. to 

 10 P.M. for a period of three months. The object of these 

 observations was to ascertain whether the principle of the 



