TO GO OUT OF THEIR WAY. 



271 



pins ; while in returning to the nest they persistently 

 came down the side of the pillar nearest to the nest, 

 though I repeatedly attempted to guide them the 

 other way. Even when placed on the paper bridge 

 between m and m', they were very dissatisfied. In 

 fact, it was obvious that they knew they were being 

 sent a long way roinid, and were attempting to make a 

 shorter cut. 



I then again placed the larvee on the column at 

 M, and when the ants were once more going to and 

 fro regularly along the paper path, I altered the 

 position of the column and larvffi to m', placing the 

 edge of the pillar, which the ants had been accustomed 

 to ascend, towards the paper bridge, connecting it with 

 the original bridge by a side- Fig. 30. 



bridge a, M being an inch from 

 the original bridge. Under 

 these circumstances three ants 

 ran on to M ; then two found 

 their way over the bridge a to 

 m'. Of the next ten ants, five 

 went to M and five over a to m\ 

 The next ten all went over the paper bridge a to m'. 



I then put the pillar and the larvge on the other side 

 of the original paper path at m'', connected with the 

 main path by a short bridge a', taking for a' a new 

 piece of paper, so that scent would be no guide. I left 

 the little bridge a in its place. The ants went as 

 follows : — 



