21 THE NATURALIST IX NICARAGUA. [Ch. II. 



of Ecitoii hamata running along the foot of a nearly 

 perpendicular tramway cutting, the side of which was 

 about six feet high. At one point I noticed a sort of 

 assembly of about a dozen individuals that appeared in 

 consultation. Suddenly one ant left the conclave, and 

 ran with great speed up the perpendicular face of the 

 cutting without stopping. It was followed by others, 

 which, however, did not keep straight on like the first, 

 but ran a short way, then returned, then again followed 

 a little further than the first time. They were evidently 

 scenting the trail of the pioneer, and making it per- 

 manently recognisable. These ants followed the exact 

 line taken by the first one, although it was far out of 

 sight. Wherever it had made a slight detour they 

 did so likewise. I scraped with my knife a small 

 portion of the clay on the trail, and the ants were com- 

 pletely at fault for a time which way to go. Those 

 ascending and those descending stopped at the scraped 

 portion, and made short circuits until they hit the 

 scented trail again, when all their hesitation vanished, 

 and they ran up and down it with the greatest confi- 

 dence. On gaining the top of the cutting, the ants 

 entered some brushwood suitable for hunting. In a 

 very short space of time the information was commu- 

 nicated to the ants below, and a dense column rushed 

 up to search for their prey. The Ecitons are singular 

 amongst the ants in this respect, that they have no 

 fixed habitations, but move on from one place to 

 another, as they exhaust the hunting grounds around 

 them. I think Eciton hamata does not stay more than 

 four or five days in one place. I hai e sometimes come 

 across the migratory columns; they nu) easily be known 



