Page - 277 - in The Origin of Species

SLAVE-MAKIKG INSTINCT 277 During the year i860, however, in the month 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, the slaves in Switzerland 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 ofiice 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 cap- tured in greater numbers in Switzerland than in England. One day I fortunately witnessed a migration of F. san- guinea from one nest to another, and it was a most interest- ing spectacle to behold the masters carefully carrying their slaves in their jaws instead of being carried by them, as in the case of F. rufescens. 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 ap- proached 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. sanguinea. The latter ruthlessly killed their small opponents, 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. At the same time I laid on the same place a small parcel of the pupx of another species, F. flava, with a few of these little yellow ants still clinging to the fragments of their nest. This species is sometimes, though rarely, made into slaves, as has been described by Mr. Smith. Althougli so small a species, it is very courageous, and I have seen it ferociously attack other ants. In one instance I found to my