Page:Encyclopædia Britannica, Ninth Edition, v. 2.djvu/107

From Wikisource
Jump to navigation Jump to search
This page needs to be proofread.
ANT
97
ants) of the pupae or immature young of other species, anc the training and subjection of these pupae as slaves anc servitors. Eegular raids and forays appear to be made by the slave-making ants upon the nests of certain species, the pupae of which, are captured, and when developed broughl into bondage and subjection to the captors.

No closer imitation of the ways of man could well be found in the entire animal economy; and the circumstances of these curious cases have been so thoroughly investigated that the matter is placed above the possibility of doubt or error. The relative position of the masters and slaves varies greatly, the extreme of hard servitorship being seen in some cases, whilst in other cases the position of the slaves is much easier. The slaves of Formica sanguined are aided by their masters in the work of the colony. But in the case of Formica rufescens the labours of the slaves are greatly increased, the entire work of the community devolving upon the unfortunate captives, and the neuters, laborious in other species, being merely employed in the duty of capturing fresh servitors. This latter trait also appears among the Amazon-ants, which literally stir neither "hand nor foot," nor make any effort to help themselves, but are waited upon and attended in the most devoted manner by their willing serfs. The slave making forays are by no means invariably destitute of bloodshed or warfare, and frequent and hot combats appear to be engaged in between the would-be masters and the species of intended slaves. Once captured, developed, and domiciled within the nests of their masters, the slave-ants appear to be thoroughly at home, and no effort at insurrection or attempt to gain their freedom appears ever to be made. The early state of development in which the pupae are generally captured, would necessarily favour the complete domestication of the captured ants within the home of the slave-making community; and the ants appear to possess and exhibit the greatest care and solicitation for the welfare of their serfs, the slaves being carried in the mouths of their owners when the latter shift their abode, or undertake any expedition leading them from home.

From the accounts of Messrs Bates and Belt, we gain some curious and interesting information regarding species of ants peculiar to South and Central America, which ex hibit marked differences in habits from all British or even other foreign species. Chief among these South American ants are the Foraging Ants (Eciton], of which there are several distinct species. These ants are truly carnivorous in their tastes, and ravage whole districts, their march being regarded with terror by the natives of Central America. Mr Bates tells us that different species have different modes, of marching, by which they may be recog nised. The Ecitons in Nicaragua are termed "Army Ants," and they appear regularly to change their hunting-grounds in quest of food. Their community comprises males and females, and two kinds of neuters or workers a "workermajor," or large-headed worker, and a small-headed kind, termed the " worker-minors." The former kind are noted for their elongated jaws; and in some species these forms are denominated " soldiers/ their peculiar office being the protection of the community from, the attacks of enemies, or the making forays on the nests of other species, or upon other animals. The habit the Ecitons have of hunting in regular organised bands, distinguishes them from other and more familiar British species (e.g., Myrmica, the Red Stinging Ant of Britain), which are predatory, but hunt in an irregular and ill-defined manner. One of the bestdefined species of foraging ants is the Eciton predator, a small species which hunts in dense hordes, and marches rapidly over a territory. A moving phalanx of this species will extend over from 4 to 6 square yards; and any unwary insect meeting with, or falling into the serried ranks, is soon torn to pieces and devoured. Eciton kamata hunts both in dense masses or in detached columns. The nature of the prey appears to regulate the mode of march. Thus, when proceeding in columns, Mr Belt found that the Eciton Jiamata was in search of the nests of another ant (Ilypoclinea), the larvas and pupae of which are seized by the Ecitons for the purpose of being broiight up as slaves, in accordance with the habits already alluded to. The Hypoclineas rush out on being attacked, bearing their pupae and larvae in their jaws; but the Ecitons at once seize the young ants, although they never appear to injure the parent Hypoclineas. The latter appear a cowardly race, as they make no effort at self-defence, their habits leading them chiefly to milk aphides, which they desert at ouce on seeing another and even smaller species of ant approach. Birds and opossums are terrified, as well as insects, at the Foraging Ants, and frequently fall victims to the deter mined onslaught of the little furies.

Fig. 2.—Leaf-cutting and Foraging Ants. 1, Œcodoma cephalus; 2, Eciton drepanophora; 3, Eciton erratica.
Fig. 2.—Leaf-cutting and Foraging Ants. 1, Œcodoma cephalus; 2, Eciton drepanophora; 3, Eciton erratica.

The other species of Ecitons comprise Eciton rapax, the largest of the race, the body of which is half-an-inch in length; Eciton legionis, famed for its ravages on other species of ants (Formicce); Eciton harnata and E. drepanopliora, nearly related species; and the so-called Blind Ecitons, thus named from, the imperfect condition of the eyes. The E. vastator and E. erratica, species of blind Ecitons, proceed on their raids by means of covered roads or ways, which are excavated and formed in front at a rate corresponding to the advance of the army.

Some interesting information regarding the senses and instincts of the Foraging Ants appears to corroborate the opinions of some earlier observers, already alluded to, on the subject. About a dozen individuals of Eciton Jiamata were observed to assemble together, as if in consultation, in a tramway excavation in Nicaragua. One ant suddenly left the assembly, and ran up the perpendicular side of the cutting. The example of this first ant was followed by several others, which ran after the first ant for a short distance, then returned, and again proceeded for a farther distance along the track of the first. The object of this proceeding was to make the track readily determinable by the succeeding travellers, and the route of the first individual was unerringly followed by the others, who were at long distances behind. A portion of the trail was removed, when the ants appeared at fault, and occupied themselves in making detours until they again hit upon the interrupted track. On arriving at the top of the excavation, a suitable spot for hunting was descried, when the information appeared to be quickly communicated to those that were aelow, and the whole army rushed upwards in obedience to the behest of the scouts. All the Foraging Ants are migratory in habits, and appear to possess no fixed place of abode, but shift their camp at intervals of from four to six or more days. The temporary abode is found in hollow trees, or under fallen trunks. An Eciton, intentionally imprisoned beneath a stone, was discovered by a companion, who at once informed his neighbours. The other ants then came to the rescue; and by biting at the stone, trying to move it, and seizing the prisoned ant by the legs, they, by their united efforts, set their companion free. An ant embedded in clay, with only the points of the antennae