KIDNAPPING ANTS AND THEIR SLAVES 



studies of ants show the tendency of many different 

 species to make common interest in one vicinage. But 

 the best-known species with claim to be ranked as 

 slave-makers are still those of Huber's classical dis- 

 covery, or their close American kin. It is interesting 

 that two species are found widely distributed in the 

 United States — one, Polyergus lucidus, the Shining Slave- 

 maker, closely related to, and the other, Formica sangui- 

 nea, subspecies rubicunda, the Sanguine Slave -maker, 

 differing little from, their European congeners — and that 

 these should have developed here the remarkable habit 

 that distinguishes them there. 



Let us follow one of these species upon a kidnapping 

 foray. As the hour approaches for the adventure, the 

 raiders issue from the city gates and assemble upon the 

 rounded exterior. As numbers increase, the excitement 

 grows. They move back and forth, aromid and around, 

 in a sort of maze, as though engaged in preliminary 

 evolutions. Frequent challenges pass, by crossing an- 

 tennae or striking them smartly upon the forehead. 

 Legs jerk nervously. Abdomens throb, rising and fall- 

 ing rapidly. There ascends a faint, crackling sound from 

 the agitated mass which covers the hill, that one fancies 

 may come from the sharp contact of numerous moving 

 insects, whose hard, chitinous skins are as veritable 

 armors as those which compassed the frames of ancient 

 warriors. But perhaps, as Professor Wheeler suggests, 

 it is a real stridulation that one hears, the sound of tiny 

 abdominal cymbals that emmets carry, and whose rasp- 

 ings, indistinguishable in the individual, are audible in 

 the mass. Has the pygmy army, then, not only its silent 

 antennal signals, but its music, too, to stir up martial 

 ardor and give stridulant calls to soldierly movements? 



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