Page:Popular Science Monthly Volume 20.djvu/546

530 quick-witted ones, become synonymous with all that is crafty and cunning.

We commenced this article mainly to call attention to some facts concerning a certain kind of ant, which must have attracted the notice of others before. It is difficult, at first, to see what special advantages can offer to the little yellow ants that persistently, year after year, construct their burrows under our brick pavements, and use these thoroughfares for their promenades and hunting-grounds. One would consider that such regions would be almost the last places these intelligent little insects would select. Many of them must be crushed daily beneath our feet, and their little hillocks and annular tumuli trod upon or swept away. Side-walks which are much traveled on are often selected by these industrious and courageous little fellows, and here they burrow beneath the bricks, and heap up their moles undaunted by the frequent demolition of their work, and the death of many of their comrades. It is obvious that the advantages must outweigh the disadvantages, otherwise the ants could not long survive, and continue their work, as they do from year to year.

We know well enough the unfavorable conditions to which they are subjected: the crushing steps of busy feet; the wheels of boys' velocipedes, and children's hoops; the sweeping-broom, a very scourge of destruction; deluges from the garden-pipe, which to them must be Noachian, and the occasional trailing of a long skirt, with the devastating effect of a typhoon and sirocco rolled into one. All these must invariably destroy many lives and demolish many an earth-work.

Among the conditions that these ants require for their perpetuation and increase are, first, soil in which they can easily burrow their nests and galleries; second, substances which may be heated by the sun, and beneath which they may bring their pupæ, or partially developed offspring, in order to hasten their more rapid development. It is said that colonies of ants have constructed their nests in or near fire-places that they might avail themselves of the artificially heated bricks of the hearth for this purpose. In pastures ants often construct their galleries beneath large stones, and bring their pupæ up from the burrows below, placing them just beneath the stone which has been heated by the sun, and which retains the heat for a considerable time after the sun sets. It is a common experience in turning over stones in the pastures to find the galleries just beneath densely crowded with pupæ, and when the ants are surprised in this way they show great solicitude in their efforts to remove the pupæ to a place of safety. It is astonishing to see how quickly many hundreds of pupæ are removed to the burrows below. In using the brick walks of cities, the ants find the most suitable conditions for their burrows, as it is customary to bed the bricks in a layer of sifted gravel, and the ants, in mining into this material, are not interrupted by the obstacles they would naturally encounter in other deposits. The bricks