Chap. VII. 
SLAVE-MAKING INSTINCT. 
221 
of July, I came across a community with an unusually 
large stock of slaves, and I observed a few slaves mingled 
with their masters leaving the nest, and marching along 
the same road to a tall Scotch-fir-tree, twenty-five yards 
distant, which they ascended together, probably in search 
of aphides or cocci. According to Huber, who had ample 
opportunities for observation, in Switzerland the slaves 
habitually work with their masters in making the nest, 
and they alone open and close the doors in the morning 
and evening; and, as Huber expressly states, their 
principal office is to search for aphides. This differ¬ 
ence in the usual habits of the masters and slaves 
in the two countries, probably depends merely on the 
slaves being captured in greater numbers in Switzerland 
than in England. 
One day I fortunately witnessed a migration of F. 
sanguinea from one nest to another, and it was a most 
interesting spectacle to behold the masters carefully 
carrying (instead of being carried by, as in the case of 
F. rufescens) their slaves in their jaws. Another day 
my attention was struck by about a score of the slave- 
makers haunting the same spot, and evidently not in 
search of food; they approached and were vigorously 
repulsed by an independent community of the slave- 
species (F. fusca) ; sometimes as many as three of these 
ants clinging to the legs of the slave-making F. san¬ 
guinea. The latter ruthlessly killed their small op¬ 
ponents, and carried their dead bodies as food to their 
nest, twenty-nine yards distant; but they were prevented 
from getting any pupae to rear as slaves. I then dug 
up a small parcel, of the pupae of F, fusca from another 
nest, and put them down on a bare spot near the place 
of combat; they were eagerly seized, and carried off by 
the tyrants, who perhaps fancied that, after all, they had 
been victorious in their late combat. 
