INTELLIGENCE OF ANTS. 823 



pursued from branch to branch and twig to twig by their remorseless 

 enemies, till, on arriving at some terminal ramification, they must 

 either submit to immediate capture by their pursuers or droj) down 

 amid the murderous hosts beneath. As already stated, all the spoils 

 which are taken by the scouts, or by the detachments sent out in an- 

 swer to their demands for assistance, are immediately taken back to 

 the main army or column. When they arrive there, they are con- 

 veyed to the rear of that column by two smaller columns of carriers, 

 which are constantly running in two double rows (one of each being 

 laden and the other not) on either side of the main column. On either 

 side of the main column there are also constantly running up and down 

 a few individuals of smaller size, lighter color, and having larger heads 

 than the other ants. These appear to perform the duty of ofiicers, for 

 they never leave their stations, and, while actively running up and 

 down the outsides of the column, they seem intent only on maintain- 

 ing order in the march stopping every now and then to touch some 

 member of the rank and file with their antennae, as if giving direc- 

 tions. 



When the scouts discover a wasp's nest in a tree, a strong force is 

 sent out from the main army, the nest is pulled to pieces, and all the 

 larvae in the nest are carried by the carrier-columns to the rear of the 

 army, while the wasps fly around defenseless against the invading 

 multitudes. Or, if the nest of any other species of ant is found, a 

 similarly strong force is sent out, or even the whole army may be de- 

 flected toward it, when with the utmost energy the innumerable insects 

 set to work to sink shafts and dig mines till the whole nest is rifled of 

 its contents. In these mining operations the Ecitons work with an 

 extraordinary display of organized cooperation ; for those low down 

 in the shafts do not lose time by carrying up the earth which they 

 excavate, but pass on the pellets to those above, and the ants on the 

 surface, when they receive the pellets, carry them only just far enough 

 to insure that they shall not roll back again into the shaft, and, after 

 having deposited them at a safe distance, immediately hurry back for 

 more. 



The Ecitons have no fixed nest themselves, but live, as it were, on 

 a perpetual campaign. At night, however, they call a halt and pitch 

 a camp. For this purpose they usually select a piece of broken ground, 

 in the interstices of which they temporarily store their plunder. In 

 the morning the army is again on the march, and before an hour or' 

 two has passed not a single ant is to be seen where thousands and mill- 

 ions had previously covered the ground. 



The habits of HJ. huinana and E. drepanophora are in general 

 similar to those of the species just described. The latter, however, 

 march in a narrower column (only four to six deep), which is there- 

 fore proportionally longer sometimes extending to over half a mile. 

 Bates tried the effect of interfering with a column of this species by 



