ANT COMMUNITIES 



surrounding locality, and serve as a sense-signal that 

 affects, even at a distance, the sensitive antennoe of 

 the workers, and so points the direct way home. Thus 

 it falls out that the return is apt to be far more direct 

 than the outgoing. 



The next outgoing naturally would be over a some- 

 what more direct trail than even their first return, and 

 so, in the course of a few trips, the first indirections 

 would be eliminated, and the trail established in its 

 lines as when I saw it. Something like this, perhaps, 

 may be a natural history of the method by which the 

 ants perform what seem to us notable engineering feats 

 in laying out their roads. 



But there are cases which cannot be explained so 

 satisfactorily. While studying the cutting ants of 

 Texas, near Austin, I took occasion to follow up the 

 underground routes of some of this species. A planter, 

 in order to get rid of the depredations of an immense 

 commune near his residence, had set his men to dig it 

 up and utterly root it out. In order to reach the central 

 nest he had traced the ants from a tree inside his home 

 premises, which they had stripped of leaves, to a point 

 six hundred and sixty-nine feet distant. The nest 

 occupied a space as large as a small cellar, the lowest 

 and main cave being as large as a flour-barrel. In this 

 central cavern were great numbers of winged males and 

 females, and innumerable lame and workers. From 

 this point radiated the various avenues over which the 

 leaf-cutters marched on their raids. 



With the aid of a young civil engineer, I proceeded to 

 survey the main course of the insects. For part of the 

 way we had but to follow the diggings of the planter's 

 laborers. For the rest, it was only necessary to sink 



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