THE ANTS OR PISMIRES 



Other nests are less simply constructed — for instance those 

 made of carton. This is a product of vegetable matter, 

 usually wood-particles, cemented together with saliva. It 

 ranges in texture from soft, leathery or friable material to 

 something which is fairly tough and may be very like wasp 

 carton. Some British ants build carton nests inside rotten 

 trees, but many tropical species build large external nests 

 which hang from the branches. There may be a number of 

 chambers, hanging from different branches and connected 



Fig. 9 



Brigade of Oecophylla smaragdina workers drawing edges of 



leaves together while other workers bind them in place with the 



silk spun by the larvae (after Doflein). 



by runways, so that most of a large tree is occupied. Other 

 nests are more like a series of purses, each under a different leaf 

 of the tree, so that the separate chambers are very numerous. 

 The most remarkable of the tree nests are those of the 

 species of Oecophylla, already briefly mentioned. The way 

 the nest is built has been watched by a number of observers 

 and the same method has been seen in several other rather 

 different kinds of ants, in other parts of the world. Several 

 ants pull the edges of two leaves together ; towards the tip 

 of the leaves where the gap between them is wider, several 

 ants form a chain, each one holding onto the one behind with 

 its hind legs. The number of ants and the length of the chain 



i35 



