TROPICAL NATURE IN COLOMBIA 



297 



entrance where there is a dump pile. Other individuals of the colony are 

 constantly moving along pathways in the forest carrying pieces of leaves. 

 The same paths are evidently used for a long time as they may be six 

 inches wide and worn (by the ants and rains) to an inch or two below 

 the surface of the ground. An ant cuts a bit of a leaf, using his man- 

 dibles like a pair of scissors, and carries it into the nest. Here the leaf 

 fragments are chewed into a pulp, spread out in beds, and planted with 

 fungus. The sole food of leaf -cutters consists of fungus raised on vege- 

 table pulp. 



The driver ants go through the forest in great swarms cleaning up 

 all the small live things as they travel. They have no home or perman- 



* T * f ■ ■ -*. Tks -A * ' * 



In the left-hand figure the white mass is a fungus garden of a leaf-cutting ant. 

 The thorns shown at the right are occupied by small ants. Note the small opening 

 which leads into the cavity within each pair of thorns. 



ent abiding place, but carry their eggs, pupae and food with them. 

 There is never any doubt when drivers are at hand, for all the sow-bugs, 

 crickets, and other small creatures which usually hide in crevices are out 

 in the open hopping hither and thither in frantic efforts to escape. The 

 drivers we saw were small blind black ants which formed a veritable 

 carpet over everything as they progressed. They covered the ground, 

 searching every nook and cranny; they climbed each tree, slowly, 

 methodically, carefully; they left no place unexplored; next day they 

 were gone. 



The foraging ants are somewhat like the drivers. They are larger 

 and many individuals have great white heads provided with a pair of 



