82 EXPEDITIONS OF POLYERGUS. 
their nest. The Rufescent ants now ascended the 
hillock, collected in crowds on the summit, and took 
possession of the principal avenues, leaving some of 
their companions to work an opening in the side of the 
ant-hill with their teeth. Success crowned their enter- 
prise, and by the newly-made breach the remainder of 
the army entered. Their sojourn war, however, of 
skort duration, for in three or four minutes they 
returned by the same apertures which gave them 
entrance, each bearing off in its mouth a larva or a 
pupa.’ 
The expeditions generally start in the afterncon, 
and are from 100 to 2,000 strong. 
Polyergus rufescens present a striking lesson of 
the degrading tendency of slavery, for these ants have 
become entirely dependent on their slaves. Even 
their bodily structure has undergone a change: the 
mandibles have lost their teeth, and have become mere 
nippers, deadly weapons indeed, but useless except in 
war. They have lost the greater part of their instincts: 
their art, that is, the power of building; their domestic 
habits, for they show no care for their own young, all 
this being done by the slaves; their industry—they 
take no part in providing the daily supplies; if the 
colony changes the situation of its nest, the masters 
are all carried by the slaves on their backs to the new 
one; nay, they have even lost the habit of feeding. 
Huber placed thirty of them with some larve and pups 
and a supply of honey in a box. ‘ At first,’ he says, 
