ANTS AND ANT LIFE. 73 



It heaped together the stalks it had loosened, and made little 

 beams of them, which it carried there and then into the nest. 

 It always came back to the same place, and appeared to 

 follow a settled plan : for it worked with eagerness and 

 patience. I then discovered a lightly traced furrow in the 

 ground. It ran in straight lines, and appeared to suggest 

 the beginning of a passage or gallery. The worker, all 

 whose actions went on under my eyes, deepened and widened 

 the furrow, and smoothed its sides : and 1 was at last con- 

 vinced that its aim was to make a way from a certain hole, 

 to the entrance of the underground nest. This passage, 

 made by a single worker, was from two to three inches long, 

 and was open above and bounded on each side by a wall of 

 earth. Its shape, resembling that of a gutter, was perfectly 

 regular ; and the little worker had not left therein a grain too 

 much. The work of this ant was so superior and accurate that 

 I could almost always recognise what it wished to do and 

 what part it built. Near the opening, where the passage 

 ended, I found a second ant, making a road exactly similar. 

 Between these roads ran a little wall, three or four lines in 

 height. When the ants are busied in building together a 

 wall, a room, or a gallery, it sometimes happens that the 

 different parts do not perfectly agree. This is not infre- 

 quent, but the ants do not allow themselves to be thereby 

 disconcerted. I will relate one case, wherein a worker dis- 

 covered its mistake and knew how to remedy it. A wall 

 had been partly erected, which appeared as though it were 

 intended to support the still unfinished arched roof of a 

 large room, which was being built from the opposite side. 

 But the worker which had begun the arch, had given it too 

 low an elevation for the wall on which it was to rest, and if 

 it had been continued on the same lines it would have 

 met the partition wall half-way up, and this was to be 

 avoided. I had just made this criticism to myself, when a 

 new arrival, after looking at the work, came to the same 

 conclusion. For it began at once to destroy what had been 

 done, to heighten the wall on which it was supported, and to 

 make a new arch with the materials of the old one under 

 my very eyes. When the ants begin an undertaking, it 

 seems exactly as if an idea slowly ripened into execution 

 in their minds. Thus, if one of them finds two stalks lying 

 Crosswise on the nest, which make possible the formation 



