Part 15

Two weeks after this, only three butterflies came to the glade, one newly painted, freshly emerged, the other two old and tattered and very weary.

I loitered on my homeward way and before I reached Kalacoon found myself in the Convict Trail in full moonlight. At one turn of the path a peculiar tinkling reached my ear. It was a veritable silver wire of sound--so high, so tenuous that one had to think as well as listen to keep it in audible focus. I pushed through a growth of cecropias and at once lost the sound never to hear it again, but in its place there appeared a very wonderful thing--a good-sized tree standing alone and exposed, bathed in full moonlight, and yet gleaming, as brightly as if silhouetted against complete darkness, by the greenish light of numberless fireflies. After the first marvel of the sudden sight, I approached and pulled down a branch and counted twenty-six glowing insects, as close together as the blossoms on a Japanese cherry branch. There were hundreds upon hundreds, all clustered together in candelabred glory, hidden from the view of all, at the farther side of this dense thicket. As I left I remembered with gratitude the silver wire of sound which had guided me, and in a far corner of my mind I stored a new memory--one which I could draw upon at need in distant times of pain, or of intolerance or perhaps in some lull of battle--the thought of a tree all aglow with living flames, in the moonlight of the Convict Trail.

WITH ARMY ANTS "SOMEWHERE" IN THE JUNGLE

Pit number five had become a shambles. Number five was one of the series of holes dug along the Convict Trail to entrap unwary walkers of the night--walkers or hoppers, for frogs and toads of strange tropical sorts were the most frequent victims. It was dug wide and deep on the slope of an ancient dune of pure white sand, a dune deep hidden in the Guiana jungle, which had not heard the rush and slither of breaking waves for centuries untold. All around this quiet glade was an almost pure culture of young cecropia trees. Day after day the pit had entrapped big beetles, rarely a mouse of some unknown species, more frequently a frog.

Now I stood on the brim, shocked at an unexpected sight. A horde of those Huns of the jungle, army ants, had made their drive directly across the glade, and scores of fleeing insects and other creatures had fallen headlong into this deep pit. From my man's height it was a dreadful encounter, but squatting near the edge it became even more terrible; and when I flattened myself on the sand and began to distinguish individuals and perceive the details from an ant's point of view, I realized the full horror and irresistibility of an assault by these ants.

One is not strongly affected by the dying struggles of a single grasshopper captured by a cuckoo or flycatcher. An individual roach being torn to pieces moves one but slightly. A batrachian, however, has more claim on our emotions, and my sympathy went out to a small, sandy-white frog who was making a brave fight for his life. The pit was alive with a host of the army ants, and wherever the little frog hopped, some soldier or heavy-jawed worker soon found him and sank jaws into his soft skin. With frantic scratching the frog would brush it off and leap again, only to be again attacked. The most horrible thing about these ants is their leaping ability. The hop of a bird or the jump of a toad when going about their usual business of life, if we think of it at all, is only amusing. But the sudden leap of a bulldog or tarantula, and the corresponding vicious attack of these ants, is particularly appalling. I saw a soldier leap a full inch and a half toward the landing thud of the frog and bite and sting at the instant of contact. I did not dare go into the pit. No warm-blooded creature could have stood the torture for more than a few seconds. So I opened my umbrella and reaching down, scooped up the sand-colored frog. A half-dozen ants came up in the same instrument, but I evaded them and tied up the tormented batrachian in my handkerchief.

My next glance into the pit showed a large toad, squatted on a small shelf of sand, close to the edge of a crowded column of ants. He was a rough old-chap, covered with warts and corrugations, and pigmented in dark gray, with mottlings of chocolate and dull red and occasional glints of gold. He was crouched flat, with all his fingers and toes tucked in beneath him. His head was drawn in, his eyes closed, and all his exposed surface was sticky with his acid perspiration--the sweat of fear. He knew his danger--of that there was no doubt--and he was apparently aware of the fact that he could not escape. Resignedly he had settled on the very line of traffic of the deadly foe, after intrenching himself and summoning to his aid all the defenses with which nature had endowed him. And he was winning out--the first vertebrate I have ever known to withstand the army ants. For a few minutes he would be ignored and his sides would vibrate as he breathed with feverish rapidity. Then two or three ants would run toward him, play upon him with their antennae, and examine him suspiciously. During this time he was immovable. Even when a soldier sank his mandibles deep into the roughened skin and wrenched viciously, the toad never moved. He might have been a parti-colored pebble embedded in its matrix of sand. Once, when three bit him simultaneously, he winced, and the whitish, acrid juice oozed from his pores. Usually the ants were content with merely examining him. I left him when I saw that he was in no immediate danger.

One other creature was quiescent in the pit and yet lived: a big, brown, hardbacked millipede. Like the frog, he fully realized his danger and had sunk his bulk partly into the sand, bending down head and tail and presenting only mailed segments. A mob of ants were trying vainly to bite their way into this organic citadel.

For the dozens of grasshoppers, crickets, roaches, beetles, spiders, ants, and harvest men, there was no escape. One daddy-long-legs did a pitiful dance of death. Supported on his eight long legs, he stood high out of reach of his assailants. He was balanced so exactly that the instant a feeling antenna touched a leg, he would lift it out of reach. Even when two or three were simultaneously threatened, he raised them, and at one time stood perfectly balanced on four legs, the other four waving in air. But his kismet came with a concerted rush of half a dozen ants, which overbore him, and in a fraction of time his body, with two long legs trailing behind, was straddled by a small worker and borne rapidly away.

I now flattened myself on an antless area at the edge of the pit and studied the field of battle. In another half-hour the massacre was almost over. Five double, and often quadruple, columns were formed up the sandy cliffs, and the terrific labor of carrying out the dead victims began. The pit was five feet deep, with perfectly straight sides, which at the rim had been gutted by the rain, so that they actually overhung. Yet the ants which had half-climbed, half-tumbled and rolled their way to the bottom in the wake of their victims, now set themselves to solving the problem of surmounting these cliffs of loose, crumbling grains, dragging loads which, in most cases, were much heavier than themselves. Imagine a gang of men set to carrying bundles of one to two hundred pounds up perpendicular cliffs twelve hundred feet in height, and the task of the army ants is made more vivid. So swiftly did they work and so constantly shifted their formations and methods of meeting and surmounting difficulties, that I felt as I used when looking at a three-ring circus. I could perceive and record only a small part of the ingenious devices and the mutual assistance and sharing of the complicated conditions which arose at every step.

Among the frightened victims, even for those endowed with excellent eyesight and powerful flight, there was only hopeless confusion and blind terror. Instead of directing their flight upward, they drove from side to side. Those whose leaps should have carried them out, simply kicked out blindly and brought up against the sandy walls.

If leaf-cutting ants had been at work here, there would have been a certain amount of cooperation. Certain ones would have cut leaves, other individuals would have picked them up and transported them. But with the army ants this mutual assistance was sublimated, developed to a quintessence of excellence. If I, seated on the rim, overlooking the whole, had been an all-powerful spirit, gifted with the ability to guide by thought simultaneously all the ants within sight, such guidance could not have bettered the cunning cooperation, the unexpectedly clever anticipation of trouble, the marvelous singleness of purpose and manifold effectiveness exhibited by these astounding creatures.

First, as to the personnel of the army ants. Roughly I divided them into two categories, white-heads and black-heads. The latter were by far the more numerous and, as a rule, were smaller, with less powerful jaws. But this did not mean that the white-heads were all soldiers. Most of them indeed were the hardest workers. Between the great extremes of size in each of these two types, there seemed to exist only a difference of degree. The smallest black-head laborers, only a little more than one-fifth of an inch long, did their bit, flew like bull pups at any prey which showed signs of life, and staggered bravely along with any piece of loot which their short legs could straddle.

The white-heads, twice as large, were the strong men of the community, putting all their activity into the labor, shouldering, pushing, dragging, lifting, singly or in unison. These persons had powerful jaws, but jaws which were stout and scissor-edged. The largest of the white-heads were armed with reaping-hooks, long inwardly-pronged jaws, curved like the tushes of ancient mammoths, too specialized for carrying loads, but well adapted for defense of the most powerful character. Yet, as we shall see, even these were not too proud to work, when occasion demanded it. But their jaws were so enormous that they had to carry themselves very erect, and they could not make quite as good time as the other castes.

All had reddish brown abdomens, with darker thoraxes and white or black heads. These heads bulged on each side like the domes of observatories. Exactly in the center of each dome, looking like the jet-black head of a tiny pin, was the single remaining facet of the eye, the degenerate residue of the hundreds which were present in their ancestors, and which the perfect males and females still possess and look through. Even this single eye is a sham, for its optic nerve dies out before the brain ganglion is reached; so we come to the astounding realization that these ants are totally blind, and carry on all their activities through the sense or senses residing in those marvelous quivering antennae. Here are beings spending all their lives in ceaseless changing activities, meeting and coping with constantly new conditions, yet wholly blind. Their sense of smell dominates their judgment of substance, and the moment an army ant reached my moccasin he sank jaws and sting deep into the fabric as instinctively and instantly as when he executed the same manoeuvers more effectively on my hand.

Keeping this handicap in mind, the achievements of these little creatures assumed a still greater significance, and with renewed interest and appreciation I again surveyed the scene in the amphitheater before me. When the majority of the pit victims had been slain, the process of carrying them up to the surface began. The hordes of ravening ants resolved themselves, as I have said, into five distinct columns of traffic which, inch by inch, fought for a footing up three of the four sides.

Half of the bottom of the pit was a sort of flat table-land several inches higher than the rest, and the first thing the ants did was to carry all their booty to this steppe, in pieces or bodily, some of the unfortunate creatures still protesting weakly as they were dragged along. In fifteen minutes the lowest part of the pit bottom was deserted, and after much hesitation I vaulted down and found a footing reasonably safe from attack.

Two traffic columns had already reached the summit, and the others were forging rapidly ahead. All used a similar method of advance. A group of mixed castes led the way, acting as scouts, sappers, and miners. They searched out every slope, every helpful step or shelf of sand. They took advantage of every hurdle of white grass-roots as a welcome grip which would bind the shifting sand grains. Now and then they had to cross a bare, barren slope with no natural advantages. Behind them pressed a motley throng, some still obsessed with the sapper instinct, widening the trail, tumbling down loose, dangerous grains. Some bore the first-fruits of victory, small ants and roaches which had been the first to succumb. These were carried by one, or at most by two ants, usually with the prey held in the jaws close beneath the body, the legs or hinderpart trailing behind. In this straddling fashion the burden was borne rapidly along, an opposite method from the overhead waving banners of the leaf-cutters.

With these came a crowd of workers, both white and black-headed, and soldiers, all empty-jawed, active, but taking no part in the actual preparation of the trail. This second cohort or brigade had, it seemed to me, the most remarkable functions of any of the ants which I saw during my whole period of observation. They were the living implements of trail-making, and their ultimate functions and distribution were so astounding, so correlated, so synchronized with the activities of all the others that it was difficult not to postulate an all-pervading intelligence, to think of these hundreds and thousands of organisms as other than corpuscles in a dynamic stream of life controlled by some single, outside mind.

Here, then, were scores of ants scrambling up the steep uneven sides, over ground which they had never explored, with unknown obstacles confronting them at every step. To the eye they were ants of assorted sizes, but as they advanced, numbers fell out here and there and remained behind. This mob consisted of potential corduroy, rope-bridges, props, hand-rails, lattices, screens, fillers, stiles, ladders, and other unnamable adjuncts to the successful scaling of these apparently impregnable cliffs. If a stratum of hard sand appeared, on which no impression could be made, a line of ants strung themselves out, each elaborately fixing himself fast by means of jaws and feet. From that moment his feverish activity left him: he became a fixture, a single unit of a swaying bridge over a chasm; a beam, an organic plank, over which his fellows tramped by hundreds, some empty, some heavily laden. If a sudden ascent had to be made, one ant joined himself to others to form a hanging ladder, up which the columns climbed, partly braced against the sandy wall.

At uncertain, unguarded turns a huge soldier would take up his station, with as many functions and duties as a member of the Broadway traffic squad. Stray, wandering ants would be set right by a single twiddle of antennae; an over-burdened brother would be given a helping jaw and assisted for some distance to the end of his beat. I was especially interested in seeing, again and again, this willingness to help bear the burdens. It showed the remains of an instinct, inhibited by over-development, by ultra-specialization of fighting paraphernalia, still active when opportunity gave it play. At the first hint, by sound or smell, of danger, the big soldier whirled outward and, rearing high on his legs, brandished his mighty blades in mid-air. Here was an ideal pacifist, who could turn his sword into a plowshare at will, and yet keep the former unsheathed for instant use.

When I watched more closely, I detected more delicate gradations of mutual aid. At the same level in two columns of ascent, the same stratum of hard sand was encountered. To one column the sand presented a rough surface which gave good foothold. Here the single line of ants which was ranged along the lower edge of the trail, in lieu of hand-rail, all faced downward, so that the ants passing above them walked partly on the abdomens and partly on the hind legs of their fellows. In the second column, the surface of the sand was smooth, and here the burdened ants found great difficulty in obtaining a foothold. In this instance the supporting gang of ants faced upward, keeping their place solely by their six sturdy legs. This left head and jaws free, and in almost every case they helped the passage of the booty by a system of passing from jaw to jaw, like a line of people handing buckets at a fire. The rightful carriers gave up their loads temporarily and devoted their attention to their own precarious footing.

I learned as much from the failures of this particular formation as from its successes. Once a great segment of a wood-roach was too much for the gallant line clinging to the sides of the pit, and the whole load broke loose and rolled to the bottom. Of the hand-rail squad only two ants remained. Yet in four minutes another line was formed of fresh ants,--ants who had never been to the spot before,--and again the traffic was uninterrupted. I saw one ant deliberately drop his burden, letting it bounce and roll far down to the bottom of the pit, and instantly take his place in the line of living guardrails. The former constituents of the line had clung to the roach segment through all its wild descent, and until it came to rest at the bottom. Without a moment's pause, they all attacked it as if they thought it had come to life, then seized it and began tugging it upward. In a fraction of time, without signal or suggestion or order, the hand-rails had become porters. The huge piece of provender had rolled close to an ascending column on the opposite side of the pit, and up this new trail the bearers started, pulling and pushing in unison, as if they had been droghers and nothing else throughout the whole of their ant-existence.

One climax of mutual assistance occurred near the rim of the pit on a level with my eyes, where one column passed over a surface which had been undermined by heavy rain, and which actually overhung. I watched the overcoming of this obstacle. All the ants which attempted to make their way up at this point lost their footing and rolled headlong to the bottom. By superformicine exertions a single small worker at last won a path to the rim at the top. Around the edge of the pit innumerable ants were constantly running, trying, on their part, to find a way down. The single ant communicated at once with all which came past, and without hesitation a mass of the insects formed at this spot and began to work downward. This could be done only by clinging one to the other; but more and more clambered down this living ladder, until it swayed far out over the vastness of the pit, three inches in length. I had never lost sight of the small worker, who had turned on his tracks and was now near the bottom of the ladder, reaching wildly out for some support--ant, grass, or sand. I was astonished to see that, as the length and consequent weight of the dangling chain increased, the base support was correspondingly strengthened. Ant after ant settled itself firmly on the sand at the top, until a mat of insects had been formed, spread out like animate guy-ropes.

At last the ultimate ant in the rope touched the upraised jaws of the soldier far below. The contact acted like an electric shock. The farthest ant in the guy-rope gang quivered with emotion, a crowd of ants climbed down and another up, and bits of insect and spider prey began to appear from the depths of the pit, over the living carpet suspended from the brim. For an inch the droghers climbed over the bodies braced against the cliff. Then, where the surface became smooth, the dangling chain came into use. Before the rim of the pit was reached, the chain had become a veritable hollow tube of ants, all with heads inward, and through this organic shaft passed the host from the ascending column. But it was far more than any mechanically built tube. When an extra large piece of loot came up, the tube voluntarily enlarged, the swelling passing along until the booty and its bearers emerged at the top.

Within five minutes after this last column was completed, there passed over it, out of the pit, a daddy-long-legs with legs trailing, perhaps the same one which I had seen in the tragic little dance of death. There followed two silvery-gray ants, a wood-roach in two installments, part of a small frog, three roaches, and two beetles. These latter gave a great deal of trouble and tumbled down the cliff again and again.

When all the columns were established and the provision trains in full movement, I leaped out and scouted round for the rest of the army. I found that the pit was only an incident. In all directions lines of ants poured past, carrying booty of all sizes and descriptions. Here and there the huge soldiers walked slowly along the outskirts, directing stragglers, looking for danger, snapping at any roach or strange ant which rushed frantically by, and holding it until it was carried off by nearby workers.

I followed a column over logs and leaves to where it ascended a cecropia tree. A harvest of small arboreal insects was being gleaned high overhead. As I watched, there came a heavy downpour of rain, a typical shower of the tropics, with a scattering of heavy drops out of the full sunshine and then a sudden clouding and a straight deluge for a few minutes. The reaction of the ants was interesting. They did not like the water, and it was comical to see them tumble over one another to get under shelter. Like the doorways of city shops in a shower, every curled-up leaf was packed, and from every crevice of bark projected sundry abdomens and hind legs for which there was no room inside. When the bearer of a large bag of booty found a convenient corner, he backed into it and left his meat sticking out in the rain.