But the life of ants is by no means given over to these bucolic pursuits. While the meadow-ants seem to be in the pastoral stage, the red species and the large black ones are hunters and warriors. The most sanguinary conflict I have witnessed was a battle of the ants. Two armies of the same black species met on the floor of a neighbor's barn. The battle lasted throughout several days, and both sides fought with indescribable ferocity. Where they came from was a mystery, as no such colonies of ants had ever been seen thereabouts. They appeared to be of the species _Formica pennsylvanica_ which nests in trees, but these do not occur in very large colonies, whereas the contending hosts upon the barn floor were as the Tartar hordes. The floor was strewn with struggling pairs and with the dead and injured, and always fresh forces were arriving. The persistence with which they fought is only to be compared to that of bulldogs, while they showed the ferocity of weasels. Once let an ant get another by the thorax and she would continue crunching and sawing until she had severed the head, notwithstanding in the meantime one or several of her own legs had been cut off by her antagonist. This was the usual outcome of the various individual combats. From time to time I placed pairs of combatants on the slide of a dissecting lens, and through the glass observed them as in an arena. It was a miniature combat of gladiators, but with no appeal for mercy on the part of the vanquished. Much evidently depended on the best hold, as in wrestling, for there was no dislodging an ant once she had secured it. Under the lens the comparatively great strength and the skill and relentless ferocity of these miniature warriors became more evident and was astonishing to witness. A bird's-eye view of the battle-field revealed no plan of action nor any directing genius. It was every one for himself--or rather herself--but there was absolute unity of purpose. Occasionally some could be seen running about with the heads of the vanquished suspended on their antennæ, whereon the jaws had closed in the death-struggle, not again to be relaxed. These ants appeared to seek no relief from such a monstrous encumbrance, nor seemingly was any offered by their comrades. Others were crawling on an uneven number of legs in search of new foes. The cause of such a conflict among ants of the same species remains a mystery--one of the many mysteries.