of which show that they were once parts of seeds, &c., the albuminous contents of which had been extracted through holes gnawed in the side,—that gave me the conviction that large stores of seed must lie hidden below in the nest; for if it were true, as some have suggested, that the ants employ the grain and seeds which they collect as materials for the construction of their nest, they would certainly not reject such parts as the chaff of grasses and the like, which are admirably suited for the purpose, and are actually used for this end by other species of ants.
It was therefore with the greatest confidence as to the result that I opened the nests of Atta barbara in search of granaries and seeds. My first attempt was made upon a nest lying in a hollow where there was a rather deep bed of soil, and the galleries extended so far on either side and in a downward direction that, though I removed enough soil to fill a wheelbarrow, I failed to reach the arcana of the nest, and saw neither chambers nor granaries.
Yet I frequently encountered workers carrying seeds downwards along the subterranean passages. I then selected a nest where the coarse and hard rock lay much nearer to the surface, barring their downward course, and compelling the ants to extend their nest in a horizontal direction.
Here, almost at the first stroke, I came upon large masses of seeds carefully stored in chambers prepared in the soil. Some of these lay in long subcylindrical galleries, and, owing to the presence in large quantities of the black shining seeds of amaranth (Amaranthus Blitum, &c.), looked like trains of gunpowder laid ready for blasting. Fig. A, Plate II. represents a trowel-
