worker-minors perform; and again, in others (E. erratica and E. vastator), the difference is so great that the distinction of classes becomes complete, one acting the part of soldiers, and the other that of workers.[1] The peculiar feature in the habits of the Eciton genus is their hunting for prey in regular bodies, or armies. It is this which chiefly distinguishes them from the genus of common red stinging-ants (Myrmica), several species of which inhabit England, whose habit is to search for food in the usual irregular manner. All the Ecitons hunt in large organised bodies; but almost every species has its own special manner of hunting.
Eciton rapax.—One of the foragers, Eciton rapax, the giant of its genus, whose worker-majors are half-an-inch in length, hunts in single file through the forest. There is no division into classes amongst its workers, although the difference in size is very great, some being scarcely one-half the length of others. The head and jaws, however, are always of the same shape, and a gradation in size is presented from the largest to the
- ↑ There is one numerous genus of South American ants in which the two classes of workers are nearly always sharply defined in structure, not only the head, but other parts of the body, being strikingly different. This is the genus Cryptocerus, of which I found fifteen species, but in no case was able to discover the distinctive function of the worker-major class. The contrast between the two classes reaches its acme in C. discocephalus, whose worker-majors have a strange dish-shaped expansion on the crown of the head. All the species inhabit hollow twigs or branches of trees, the monstrous-headed individuals being always found quiescent and mixed with crowds of worker-minors. It cannot be considered wonderful that the function of worker-majors has not been discovered in exotic ants, when Huber, who devoted a life-time to the study of European ants, was unable to detect it in a common species, the Formica rufescens.
