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THE POPULAR SCIENCE MONTHLY.
whence they rolled down to the bottom, where another relay of laborers picked them up and carried them to the new burrow. It was amusing to watch the ants hurrying out with bundles of food, dropping them over the slope, and rushing back immediately for more.

Ants of this genus are very clever at making tunnels. The Rev. H. Clark says that in one case they have made a tunnel of enormous length under the river Parahylia, where this is as broad as the Thames at London—their object being to reach a storehouse which is on the opposite bank. This statement is not to be considered so incredible as it at first sight unquestionably appears, for Bates has seen the subterranean passages of these ants extending to a distance of seventy yards.

Harvesting Ants.—The harvesting ants belong almost exclusively to a single genus, which, however, comprises a number of species distributed in localized areas over all the four quarters of the globe. Their distinctive habits consist in gathering nutritious seeds of grasses during summer, and storing them in granaries for winter consumption. We owe our present knowledge concerning these insects mainly to Moggridge, who studied them in the south of Europe, Lincecum and McCook, who studied them in Texas; Colonel Sykes and Dr. Jerdon also made some observations upon them in India. They likewise occur in Palestine, where they were clearly known to Solomon and other writers of antiquity, whose claim to accurate observation in this matter has within the last few years been amply vindicated, after having been for many years discredited, on account chiefly of the adverse statements of Huber.

Moggridge found that from the nest in various directions there proceed outgoing trains, which may be thirty or more yards in length, and each consisting of a double row of ants moving in opposite directions. Like the leaf-cutting ants, those composing the outgoing train are empty-handed, while those composing the incoming train are laden. But here the burdens are grass-seeds. At their terminations in the foraging-ground, or ant-fields, the insects composing these columns disperse by hundreds among the seed-yielding grasses. They then ascend the stems of the grasses, and, seizing the seed or capsule in their jaws, fix their hind-legs firmly as a pivot, round which they turn and turn till the stalk is twisted off. The ant then descends the stem,

patiently backing and turning upward again as often as the clumsy and disproportionate burden becomes wedged between the thickly-set stalks, and joins the line of its companions to the nest. . . . Two ants sometimes combine their efforts, when one stations itself near the base of the peduncle, and gnaws it at the point of greatest tension, while the other hauls upon it and twists it. . . . I have occasionally seen ants, engaged in cutting the capsules of certain plants, drop them, and allow their companions below to carry them away; and this corresponds with the curious account given by Ælian of the manner in which the spikelets of corn are severed and thrown down "to the people below."