THE COMMUNITY OF THE ANTS 



I myself have searched for ants which might be hostile to the 

 Sauvas. Near a Sauvas' nest on the monastery farm stood a small 

 tree on which lived some large black ants which sucked the sap of 

 plants. If I brought a Sauva to this tree these ants immediately 

 seized and killed it, or at least dragged it away, hurrying down the 

 trunk of the tree. Undoubtedly these ants protected the trees, yet 

 they would not fight the Sauvas in their nest. I often noticed, 

 at night, when the black ants began to spread over the ground, 

 that if they approached a Sauvas' nest they were defeated or put 

 to flight by the soldiers. 



There were similar battles when a nest of small black ants was 

 uncovered on excavating a Sauvas' nest. When the terrified Leaf- 

 cutting Ants entered the black ants' nest they were at once attacked 

 by ten or twenty of the dwarfs, and slain. For that matter, the Sauvas' 

 nest contained a number of nests of other species. Embedded in the 

 midst of the fungus-chambers was a thick ball of clay, which was the 

 nest of a species of Termite (Syntermes), and the walls of this nest 

 were traversed by the tiniest galleries, which were themselves the 

 dwelling-place of a thieving ant, Solenopsis Eduardi. The Solenopses 

 had just produced their sexual forms, and the winged ants were 

 pouring forth in all directions. There are thriving ants in the nests 

 of yetot her species ; the thieves are always smaller than their hosts, 

 and the galleries leading to their nest are so narrow that no other 

 ants can enter them. Accordingly, when they are pursued by their 

 hosts they have only to withdraw into their corridors. There they 

 are safe. Many of these thieving ants are very dangerous housemates; 

 they slip unawares out of their hiding-places, to seize an egg or a 

 larva of the larger species, and hasten back to safety with their booty. 



In the interior of Pernambuco I encountered the giant of the 

 Brazilian ants (Dinoponera grandis, Plate 29, II, 11). The workers 

 of this powerful species are an inch and a quarter in length. These 

 black ants wander singly over the soil of a freshly-planted cotton- 

 field, in which they have excavated their galleries; here they feed 

 their larvae on the fragments of dissected insects, and they do this — 

 unlike other ants — without first swallowing the food themselves, and 

 then disgorging it! The group to which these ants belong betrays, 

 by yet another peculiarity, the fact that it stands at the lowest level 

 of myrmecaean evolution ; namely, like the wasps they carry a sting 

 at the tip of the abdomen, whUe the higher ants have lost their sting, 

 and have retained only the poison-glands. They bite their victims 

 with their pincers, and then squirt their "formic acid" into the 



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