WHITE ANTS 165 



The ants worked so fast that during the half-hour that 

 I sat watching them the towers had all risen in height 

 at least an inch. The ants must have continued thus 

 working the whole of the day and perhaps for some 

 part of the night as well, for when I visited the nest 

 the next morning the towers had all risen to the height 

 of two and three feet, and several of them had also 

 been arched over. In others the process of arching 

 over was just commencing. I remained for a long time 

 and watched it. The process was most interesting to 

 observe, but owing to the extremely minute size of the 

 pellets, it was a process not easy to observe correctly. 

 So far as I could make out, the process was as follows : 



The circumference of the tower was first reduced 

 by placing the pellets so that they overlapped a little 

 inwardly. The overlapping in each successive row was 

 so slight as to be hardly perceptible. But after several 

 rows of pellets had thus been laid the circumference 

 appeared decidedly smaller ; next the wall commenced 

 to bend over inwardly, and presently it became nearly 

 horizontal. The pellets were now clearly kept in 

 position by some glutinous substance, which caused 

 each successive pellet to adhere to the one against 

 which it was placed. 



I noticed now that the white ants placed the pellets 

 in their positions with extreme care ; they also appeared 

 to moisten the pellets repeatedly with their tongues, 

 both before and after they were deposited. The 

 process of arching over was completed while I looked 

 on. The summit of the tower had now the appearance 

 of a very flat but very rough and uneven dome. 



