TERMITES, THE DESTROYERS 71 



arched tunnels. If there is nothing soHd on which 

 their pathway can rest, they build a round tube. 

 The same clay-and-paper mixture is used here 

 as in the nest. 



The workers venture out from the open end 

 of the runway less than half an inch, carrying 

 their tiny speck of material to extend the tunnel. 

 On the roadway marked out by the first workers 

 the others pat in place their little balls before the 

 mixture hardens. A little more than an inch of 

 tunnel can be made in an hour. 



These covered roads, branching frequently, lead 

 off from the big nests down the trunks of the 

 trees. One tree of which I took a picture had a 

 network of tunnels over its bark like the veins 

 under the thin skin of a race horse (Fig. 32). 

 Some of the runways end at the ground where the 

 termites get water and dig clay mines and con- 

 struct underground nests. Others are built as far 

 as three hundred feet from the main nest and 

 end in smaller tree nests. Often these smaller 

 nests are on dead timber. Where the jungle has 

 been cleared away and people are trying to farm, 

 their fence posts are often capped with the 

 smaller nests. 



The termites are very enterprising in their road 

 building. I found they had invaded the bed of 

 a stream that three months before in the wet 

 season had been a raging torrent, though now 

 it was only a little brook. Their arched runway 

 led from a moist and decaying palm, across a 



