THEIR ARCHITECTURE. 181 



The leaves being very much larger than the ants 

 which carry them, the latter are quite hidden beneath 

 the green burden. It was at one time thought that the 

 leaves were carried in order to keep the sun's rays off 

 the insect, which was therefore called the Parasol 

 Ant. It is now, however, known that the ant simply 

 holds the leaf aloft, because it is the easiest method of 

 carrying it. 



Though the small workers bring the leaves, they are 

 not allowed to lay them. That department is taken by 

 the large-headed workers, who receive the materials 

 but allow none but themselves to arrange them. In 

 fact, the line of demarcation is as strongly shown among 

 ants as among our own bricklayers, none of whom will 

 condescend to carry either hod or mortar, and will not 

 suffer a mere labourer to lay a brick. 



The extent of the Saiiba's tunnelling is almost 

 incredible, and their galleries often do very much harm 

 in civilised localities. They have been known to pierce 

 an embankment, and cause a flood by letting out the 

 water; and I know of a case where a gold mine in 

 Brazil was totally rained by the Saiibas, which had 

 driven an unsuspected gallery into it just before the 

 rainy season. Accordingly, when the rains came the 

 water rushed in a torrent through the mine, washed 

 away the wooden roof and uprights, destroyed the 

 tram, and not only stopped the progress of the mine, 

 but necessitated the reconstruction of the damaged 

 gallery before the ore could be taken to the " stamps " 



