214 SPECIAL INSTINCTS. Chap. VII. 



more numerous ; but Mr. Smith informs me that he has watched 

 the nests at various liours during' May, June, and Aui^ust, both 

 in Surrey and Hamjishire, and lias never seen tlie slaves, 

 thougli present in large nundjers in August, either leave or 

 enter the nest. Hence he considers them as strictly house- 

 hold slaves. The masters, on the other hand, maybe constant- 

 ly seen bringing' in materials for the nest, and food of all kinds. 

 During the ^-ear 18G0, 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, 

 prol)ably in search of aphides or cocci. According to Huber, 

 who had ample opportimitics for observation, the slaves in 

 Switzerland habitually Avork with their masters in making the 

 nest, and they alone open and close the doors in the morning 

 and evening; and, as Pluber expressly states, their jmncipal 

 office is to search for aphides. This difference in the usual 

 habits of the masters and slaves in the two coinitries probably 

 depends merely on the slaves being captured in greater num- 

 bers in Switzerland than in England. 



One day I fortunately witnessed a migration of F. sanguinea 

 from one nest to another, and it Avas a most interesting spec- 

 tacle 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 approached and were vigorously 

 repulsed b}^ an independent community of the slave-species 

 (F. fusca) ; sometimes as many as tliree of these ants cUnging 

 to the legs of the slave-making F. sanguinea. The latter ruth- 

 lessly 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 pupre to rear as slaves. 

 I then dug up a small parcel of the pupa? 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, tliC}' had been vic- 

 torious in their late combat. 



At the same time I laid on the same place a small parcel 

 of the ]nipre of another species, F. flava, with a few of these 

 little yellow ants still clinging to the fragments of their nest. 

 Tliis species is sometimes, though rarely, made into slaves, as 



