On another occasion observed by Forel, in which several fertile Amazons also took part and killed many enemies, the nest was thoroughly ravished, but the retreat was also in this case very much disturbed and harassed by the superior numbers of the enemy. There were many slain on both sides. That in spite of the above-mentioned unanimity different opinions among the members of an expedition sometimes hinder its conduct, the following observation seems to show:—An advancing column divided after it had gone about ten yards from the nest. Half turned back, while the other half went on, but after some time hesitated and also turned back. Arrived at home, it found those which had formerly turned back putting themselves in motion in a new direction. The newly returned followed them, and the reunited army, after various wheelings, halts, &c., at last turned home again by a long way round. The whole business looked like a promenade. But apparently different parties had different nests in view, while others were entirely against the expedition. Yet perhaps it was only a march for exercise.
Outer obstacles do not, as a rule, hinder the Amazons when they are once on the march. Forel saw them wade through some shallow water, although many were drowned in it, and then march over a dusty high road, although the wind blew half of them away. As they returned, booty-laden, neither wind, nor dust, nor water could make them lay down their prey. They only got back with great trouble, and turned back again to bring fresh booty, although many lost their lives.
The following is also quoted from Büchner's excellent epitome of Forel's observations in this connection:—
The most terrible enemy of the Amazons is the sanguine ant (F. sanguinea), which also keeps slaves, and thereby often comes into collision with the Amazons on their marauding excursions. It is not equal to it in bodily strength or fighting capacity, but surpasses it in intelligence; according to Forel it is the most intelligent of all the species of ants. If Forel, for instance, poured out the contents of a sack filled with a nest of the slave species near an Amazon nest, the Amazons apparently generally regarded the tumbled together heap of ants, larvæ, pupæ, earth, building materials, &c., as the dome of a hostile nest, and took all imaginable but useless pains to find out the entrances thereinto, leaving on one side for this investigation their only object, the carrying off the pupæ; but the sanguine ants under similar circumstances did not allow themselves to be deceived, but at once ransacked the whole heap.
On another occasion, while a procession of Amazon ants was on its way to plunder a nest of F. fusca, before it arrived Forel poured out a sack-full of sanguine ants, and made a break in the nest:—
The sanguine ants pressed in, while the fusca came out to defend themselves. At this moment the first Amazons arrived. When they saw the sanguine ants they drew back and awaited the main army, which appeared much disturbed at the news. But once united, the bold robbers rushed at their foes. The latter gathered together and beat back the first attack, but the Amazons closed up their ranks and made a second assault, which carried them on to the dome and into the midst of the enemy. These were overthrown, as well as a number of F. pratensis, which Forel at this moment poured out on the nest. The conquerors delayed for a moment on the dome after their victory, and then entered the nest to bring out a little of the valuable booty. A few Amazons which were mad with anger did not return with the main army, but went on slaughtering blindly among the conquered and the fugitives of the three species, fusca, pratensis, and sanguinea.
The ravished rufibarbes once became so desperate at their overthrow that they followed the robbers to their own nest, and the latter had some trouble in defending it. The rufibarbes let themselves be killed in hundreds, and really seemed as though they courted death. A small number of the Amazons also sank under the bites of their enemies. The nest contained slaves of the rufibarbis species, which on this emergency fought actively against their own race. There were also slaves of the species fusca, so that the nest included three different species of ants.
The same nest is often revisited many times on the same day or at different periods, until either there is no more to steal, or the plundered folk have hit upon better mode of defence. A column which was in the act of going back to such a plundered nest turned when halfway there, and halted, apparently on no other ground than because it had met the rearguard of the army, and had learned that the nest was exhausted, and that there was nothing more to be had there. The robbers then went off to a rufibarbis nest which was in the neighbourhood, and killed half the inhabitants while plundering the nest. The surviving rufibarbes returned after the robbery and brought up new progeny; but thirteen days later the Amazons again reaped a rich harvest from the same nest. The Amazon army often severs itself into two separate divisions when there is not enough for both to do at the same spot. Sometimes one division finds something and the other nothing, and they then reunite. If any obstacle be placed in their way they try to overcome it, in doing which some leave the main army, lose themselves, and only find their way home again with difficulty. Forel has tried to establish the normal frequency of expeditions, and found that a colony watched by himself for a space of thirty days sent out no less than forty-four marauding excursions. Of these about eight-and-twenty were completely, nine partially, and the remainder not at all successful. He four times saw the army divide into two. Half the expeditions were levelled against the rufibarbes, half against the fuscæ. On an average a successful expedition would bring back to the colony a thousand pupæ or larvæ. On the whole, the number of future slaves stolen by a strong colony during a favourable summer may be reckoned at forty thousand!
The internecine battles which occasionally break out among the Amazons themselves are naturally the most cruel. They tear each other to pieces with incredible fury, and knots of five or six individuals which have pierced each other may be seen rolling over each other on the ground, it being impossible to distinguish between friend and foe. Civil wars among men are also known to be the most embittered and the most bloody.
The mode of attack practised by the other best known species of slave-making ant, sanguinea, is somewhat different:—