i8 



PARA 



and orange trees. It has not hitherto been shown satis- 

 factorily to what use it appUes the leaves. I discovered 

 it only after much time spent in investigation. The 

 leaves are used to thatch the domes which cover the 

 entrances to their subterranean dwellings, thereby pro- 

 tecting from the deluging rains the young broods in the 

 nests beneath. The larger mounds, already described, are 

 so extensive that few persons would attempt to remove 

 them for the purpose of examining their interior ; but 

 smaller hillocks, covering other entrances to the same 

 system of tunnels and chambers may be found in sheltered 

 places, and these are always thatched with leaves, mingled 

 with granules of earth. The heavily-laden workers, each 

 carrying its segment of leaf vertically, the lower edge 

 secured in its mandibles, troop up and cast their burthens 

 on the hillock ; another relay of labourers place the 

 leaves in position, covering them with a layer of earthy 

 granules, which are brought one by one from the soil 

 beneath. 



The underground abodes of this wonderful ant are 

 known to be very extensive. The Rev. Hamlet Clark 

 has related that the Saiiba of Rio de Janeiro, a species 

 closely allied to ours, has excavated a tunnel under the 

 bed of the river Parahyba, at a place where it is as broad 

 as the Thames at London Bridge. At the Magoary rice 

 mills, near Para, these ants once pierced the embank- 

 ment of a large reservoir : the great body of water which 

 it contained escaped before the damage could be repaired. 

 In the Botanic Gardens, at Para, an enterprising French 

 gardener tried all he could think of to extirpate the 

 Saiiba. With this object he made fires over some of the 

 main entrances to their colonies, and blew the fumes of 

 sulphur down the galleries by means of bellows. I saw 

 the smoke issue from/a great number of outlets, one of 

 which was 70 yards distant from the place where the 

 bellows were used. This shows how extensively the under- 

 ground galleries are ramified. 



Besides injuring and destroying young trees by de- 

 spoiling them of their foliage, the Saiiba ant is trouble- 

 some to the inhabitants from its habit of plundering the 

 stores of provisions in houses at night, for it is even more 

 active by night than in the daytime. At first I was 

 inclined to discredit the stories of their entering habita- 

 tions and carrying off grain by grain the farinha or man- 



