The _Formica sanguinea_ takes possession of the eggs of the _Formica fusca_ and rears them with its own. When the slaves reach the adult condition they live beside their masters and share their labours, for the latter work, are skilful in all tasks, and can by their own activity construct an ant-hill and keep it going. If they desire servants, it is not in order to throw all the work on them, but to have intelligent assistants. This is the primitive form of slavery as it first existed among men. It was not until later that it became modified, to become at last an institution against which the sentiment of justice arose. Other species of Ants have pushed the exploitation of slaves to a point Man has never reached. But the _Formica sanguinea_ are companions to their helpers rather than masters, and even show them great consideration. When the colony emigrates one may see the owners of the nest, who are of larger size than the _Formica fusca_, take these up in their jaws and carry them the entire way. The Amazons (_Polyergus rufescens_) act otherwise. Very skilful in obtaining slaves and powerfully armed for triumphant raids, their nests always contain legions of servants, and the custom of being waited upon has become so impressed on the race by heredity that it is an instinct stronger even than personal preservation. The master ant has not only lost the taste and the idea of work, but even the habit of feeding himself, and would die of hunger beside a pile of honey or sugar if a grey ant was not there to put it into his mouth. Thus Huber, the earliest accurate observer of these ants, enclosed thirty Amazons with several pupae and larvae of their own species, and twenty negro pupae, in a glass box, the bottom of which was covered with a thick layer of earth; honey was given to them, so that, although cut off from their auxiliaries, the Amazons had both shelter and food. At first they appeared to pay some little attention to the young; this soon ceased, and they neither traced out a dwelling nor took any food; in two days one-half died of hunger, and the other remained weak and languid. Commiserating their condition, he gave them _one_ of their black companions. This little creature, unassisted, formed a chamber in the earth, gathered together the larvae, put everything into complete order, and preserved the lives of those which were about to perish.