104 ANIMAL INTELLIGENCE. 



as many as seven. They are usually two to three inches 

 wide at their origin, but in large nests may be as much as 

 five. MacCook found no road longer than sixty feet, but 

 Lincecum describes one of three hundred feet. Along 

 these hard and level roads there is always passing, during 

 the daytime of the harvesting season, a constant stream 

 of ants those going from the nest being empty-handed, 

 and those returning to it being laden with seeds. Of 

 course the incoming ants, converging from all quarters 

 upon the road, and therefore increasing in numbers as they 

 approach the nest, require greater space for free locomo- 

 tion ; while the outgoing ants, diverging as they get further 

 from home, also require greater proportional space the 

 less their distance from the nest : hence the gradual 

 swelling in the width of the roads as they approach the 

 nests. 



The manner of collecting the seeds in the jungle sur- 

 rounding the roads is thus described by MacCook : 



At last a satisfactory seed is found. It is simply lifted from 

 the ground, or, as often happens, has to be pulled out of the 

 soil into which it has been tightly pressed by the rain or by 

 passing feet. Now follows a movement which at first I 

 thought to be a testing of the seed, and which, indeed, may be 

 partially that; but finally I concluded that it was the adjusting 

 of the burden for safe and convenient carriage. The ant pulls 

 at the seed-husk with its mandibles, turning and pinching or 

 ' feeling ' it on all sides. If this does not satisfy, and commonly 

 it does not, the body is raised by stiffening out the legs, the 

 abdomen is curved underneath, and the apex applied to the seed. 

 I suppose this to be simply a mechanical action for the better 

 adjusting of the load. Now the worker starts homeward. It 

 hap not lost itself in the mazes of the grass forest. It turns 

 directly towards the road with an unerring judgment. There 

 are many obstacles to overcome. Pebbles, pellets of earth, bits 

 of wood, obtruding rootlets, or bent-down spears of grass block 

 up or hinder the way. These were scarcely noticed when the 

 ant was empty-handed. But they are troublesome barriers now 

 that she is burdened with a seed quite as thick, twice as wide, 

 and half as long as herself. It is most interesting to see the 

 skill, strength, and rapidity with which the little harvester 

 swings her treasure over or around, or pushes it beneath these 

 obstacles. Now the seed has caught against the herbage as the 



