Page:Harvesting ants and trap-door spiders. Notes and observations on their habits and dwellings (IA harvestingantstr00mogg).pdf/57

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found stored with seeds, and lying at depths below the surface, varying from one to twenty inches.

A diagram is given in the preceding woodcut of a vertical section of a nest of barbara lying in soil sixteen inches deep, the granaries being at 1-1/2, 2, 4, 6, 9, and 12-1/2 inches, as determined by actual measurement on the spot.

In some cases, and especially where the soil is shallow, the galleries and granaries are much crowded together, as is shown in Plate IV., which represents a small mass of earth, pierced by the roots of plants, taken out of a nest of barbara, lying at two inches below the surface. When first opened all these granaries were filled with seeds.

The shape of the granary chambers varies considerably, as may be seen by reference to the drawing of three floors given in Plate III., p. 23, and that shown diagrammatically in the woodcut on next page, where the white space represents the granary floor, and the dark circular spot in the centre, the aperture of a gallery leading downwards.

I once had an opportunity of seeing a large portion of a nest of the red-headed variety of barbara laid bare by a cutting recently made through a bank at Cannes in digging the foundations of a house, which exposed a very extensive and complicated series of galleries and granaries. The lowest point at which I detected the workings of the ants was at twenty inches below the surface of the ground, and here granaries containing seeds in abundance were present, and the galleries and granaries extended over a space measuring 5ft. 9in. in a horizontal direction. In two cases I have found nests of Atta barbara at Mentone which were carried