fusca), and she instantly set to work, fed and saved the survivors; made some cells and tended the larvae, and put all to rights.

What can be more extraordinary than these well-ascertained facts? If we had not known of any other slave-making ant, it would have been hopeless to speculate how so wonderful an instinct could have been perfected.

Another species, Formica sanguinea, was likewise first discovered by P.