It would be of interest to learn the extent and manner of concealment of these large stores of grain, but, during the months from October to May, I have never seen corn in any quantity in the granaries, though there was frequent evidence of its late presence in the dense masses of husks of oats and other large grain lying near the nests. In October, 1873, I found near the entrances to a nest of _structor_ a circular mound formed of this refuse, twenty-seven inches in diameter, and averaging two inches in thickness, while near other nests I have found the chinks between the stones of the terrace-wall behind which the nest lay, literally stuffed with husks. It was plain that these grains of cereals and the larger grasses had been collected during the summer. The granaries in the winter and spring contain the grains of some few of the autumnal grasses, but are principally filled with seeds of the other more abundant autumn-fruiting plants belonging to the neighbourhood.
I have now collected from the granaries of these ants the seeds or small dry fruits of fifty-four distinct species of wild plants, and on examination I find that during my stay in the south (from October to May) the seeds of the distinctively spring and summer-flowering plants are either entirely absent or are very scarce, while the great bulk of the seeds belong to plants which ripen their fruits in the autumn. Thus the grains of oats, of the large fescue and brome grasses, of quaking grasses (_Melica_), and other kinds common near the nests in May, are conspicuously absent in the winter, as are the fruits of all the sedges but one, and this one (_Carex distans_) retains its fruits till late in the autumn. Among other spring-flowering plants common near the nests, the seeds of which are also absent, I may mention violets (_Viola odorata_), poppies, (_Papaver_), certain species of _Veronica_, _Helianthemum guttatum_, _Silene quinque-vulnera_ and _Plantago Bellardi_.
Here a curious question arises--viz., What becomes of the large stores of seeds which one may still find in the nests in May, when the ants are busy pouring fresh supplies into the nest? The answer probably is, that, as the weather becomes warmer, ever-increasing calls are made by the larvæ upon the food-resources of the nest, and that old and new seeds rapidly disappear together, and all the energy and activity of the colony is needed to meet the increased demand.