358 ANIMALS OF EGA. Chai\ V. 



The errand of the vast ant-armies is plunder, as in 

 the case of Eciton legionis ; but from their moving 

 always amongst dense thickets, their proceedings are 

 not so easy to observe as in that species. Wherever 

 they move, the whole animal world is set in commo- 

 tion, and every creature tries to get out of their way. 

 But it is especially the various tribes of wingless insects 

 that have cause for fear, such as heavy-bodied spiders, 

 ants of other species, maggots, caterpillars, larvae of 

 cockroaches and so forth, all of which live under 

 fallen leaves, or in decaying wood. The Ecitons do not 

 mount very high on trees, and therefore the nestlings 

 of birds are not much incommoded by them. The mode 

 of operation of these armies, which I ascertained only 

 after long-continued observation, is as follows. The 

 main column, from four to six deep, moves forward in 

 a given direction, clearing the ground of all animal 

 matter dead or alive, and throwing off here and there, 

 a thinner column to forage for a short time on the 

 flanks of the main army, and re-enter it again after 

 their task is accomplished. If some very rich place be 

 encountered anywhere near the line of march, for 

 example, a mass of rotten wood abounding in insect 

 larvae, a delay takes place, and a very strong force of ants 

 is concentrated upon it. The excited creatures search 

 every cranny and tear in pieces all the large grubs they 

 drag to light. It is curious to see them attack wasps' 

 nests, which are sometimes built on low shrubs. They 

 gnaw away the papery covering to get at the larvae, 

 pupae, and newly-hatched wasps, and cut everything to 

 tatters, regardless of the infuriated owners which are 



