Part 11

Such treats--floral and avian--were all that might be expected of any tree, but the cashews had still more treasures in store. The weeks passed and we had almost forgotten the flowers and hummingbirds, when a new odor greeted us, the sweet, intense smell of overripe fruit. We noticed a scattering of soft yellow cashews fallen here and there, and simultaneously there arrived the hosts of fruit-eating birds. From the most delicate turquoise honey-creepers to great red and black grosbeaks, they thronged the trees. All day a perfect stream of tanagers--green, azure and wine-colored--flew in and about the manna, callistes and silver-beaks, dacnis and palm tanagers. And for a whole week we gloried in this new feast of color, before the last riddled cashew dropped, to be henceforth the prize of great wasps and gauze-winged flies, who guzzled its fermented juice and helped in the general redistribution of its flesh--back to the elements of the tropic mold, to await the swarms of fingering rootlets, a renewed synthesis--to rise again for a time high in air, again to become part of blossom and bird and insect.

It was along this Convict Trail that I sank the series of pits which trapped unwary walkers of the night, and halfway out at pit number five, the army ants waged their wonderful warfare.

In fact it was while watching operations in another sector of this same battle-front that I found myself all unintentionally in the sleeping chamber of the heliconias.

Tired from a long day's work in the laboratory, I wandered slowly along the Convict Trail, aimlessly, in that wholly relaxed state which always seems to invite small adventures. It is a mental condition wholly desirable, but not to be achieved consciously. One cannot say, "Lo, I will now be relaxed, receptive." It must come subconsciously, unnoticed, induced by a certain wearied content of body or mind--and then--many secret doors stand ajar, any one of which may be opened and passed if the gods approve. My stroll was marked at first, however, by only one quaint happening. For several weeks the jolly little trail-lizards had been carrying on most enthusiastic courtships, marked with much bowing and posing, and a terrific amount of scrambling about. The previous day--that of the first rains--numbers of lizardlets appeared, and at the same time the brown tree-lizards initiated their season of love-making. I had often watched them battle with one another--combats wholly futile as far as any damage was concerned. But the vanquished invariably gave up to his conqueror the last thing he had swallowed, the victor receiving it in a gluttonly rather than a gracious spirit, but allowing his captive to escape. I surprised one of these dark-brown chaps in the trail and seized him well up toward the head, to preserve his tail intact. Hardly had I lifted him from the ground, when he turned his head, considered me calmly with his bright little eyes, and forthwith solemnly spat out a still living ant in my direction. The inquiring look he then gave me, was exceedingly embarrassing. Who was I not to be bound in chivalry by the accredited customs of his race?

With dignity and certainty of acceptance he had surrendered, calmly and without doubt he had proffered his little substitute of sword. It was, I felt, infinitely preferable to any guttural and cowardly "kamerad!" Feeling rather shamefaced I accepted the weakly struggling ant, gently lowered the small saurian to the ground and opened my fingers. He went as he had surrendered, with steadiness and without terror. From the summit of a fallen log he turned and watched me walk slowly out of sight, and I at least felt the better for the encounter.

Of all tropical butterflies, heliconias seem the most casual and irresponsible. The background of the wings of many is jet-black, and on this sable canvas are splashed the boldest of yellow streaks and the most conspicuous of scarlet spots. Unquestionably protected by nauseous body fluids, they flaunt their glaring colors in measured, impudent flight, weaving their way slowly through the jungle, in the face of lizard and bird. Warningly colored they assuredly are. One cannot think of them except as flitting aimlessly on their way, usually threading the densest part of the undergrowth. No butterflies are more conspicuous or easier to capture. They must feed, they must pay court and mate, and they must stop long enough in their aimless wanderings to deposit their eggs on particular plants by an instinct which we have never fathomed. But these are consummations hidden from the casual observer.

Now, however, I am prepared for any unexpected meaningful trait, for I have surprised them in a habit, which presupposes memory, sociability and caution, manifested at least subconsciously.

The afternoon had worn on, and after leaving my lizard, I had squatted at the edge of a small glade. This glade was my private property, and the way by which one reached it from the nearby Convict Trail was a pressure trail, not a cut one. One pushed one's way through the reeds, which flew back into place and revealed nothing. Lifting my eyes from the tragedies of a hastening column of army ants, I saw that an unusual number of heliconias were flitting about the glade, both species, the Reds and the Yellows. All were fluttering slowly about and as I watched, one by one they alighted on the very tips of bare twigs, upside down with closed wings. In this position they were almost invisible, even a side view showing only the subdued under-wing pigments which blended with the pastel colors of twilight in the glade, reflected from variegated leaves and from the opening blossoms of the scarlet passion vine. Perhaps the most significant fact of this sleeping posture, was the very evident protection it afforded to butterflies which in motion during their waking hours are undoubtedly warningly colored and advertised to the world as inedible. Hanging perpendicularly beneath the twig, although they were almost in the open with little or no foliage overhead, yet they presented no surface to the rain of the night, and all faced northeast--the certain direction of both rain and wind.

The first one or two roosting butterflies I thought must be due to accidental association, but I soon saw my error. I counted twelve of the Red-spots and eight Yellows on two small bushes and a few minutes' search revealed forty-three more. All were swung invariably from the tips of bare twigs, and there was very evident segregation of the two kinds, one on each side of the glade.

When I disturbed them, they flew up in a colorful flurry, flapped about for a minute or less and returned, each to its particular perch. After two or three gentle waves of the wings and a momentary shifting of feet they settled again to perfect rest. This persistent choice of position was invariably the case, as I observed in a number of butterflies which had recognizable tears in their wings. No matter how often they were disturbed they never made a mistake in the number of their cabin. A certain section of a particular twig on a definite branch was the resting place of some one heliconia, and he always claimed it.

Several were bright and fresh, newly emerged, but the remainder were somewhat faded and chipped at the edges. The delicate little beings slept soundly. I waited until dusk began finally to settle down and crept gently toward a Red-spot. I brought my face close and aroused no sign of life. Then I reached up and slowly detached the butterfly from its resting place. It moved its feet slightly, but soon became quiet. Then I gently replaced it, and at the touch of the twig, its feet took new hold. When I released its wings it did not fly but sank back into the same position as before. I wondered if I was the first scientist to pluck a sleepy butterfly from a jungle tree and replace it unawakened. At the time I was more impressed by the romantic beauty of it all than by its psychological significance. I wondered if heliconias ever dreamed, I compared the peacefulness of this little company with the fierce ants which even now were just disappearing from view. These were my thoughts rather than later meditations on whether this might not be a sort of atavistic social instinct, faintly reminiscent of the gregariousness of their caterpillar youth.

From any point of view I shall think better of all butterflies for this discovery; their desire for company, the instinctive wisdom of place and posture, the gentleness and silence of the little foregathering in the jungle. As I walked back along the trail several late comers passed me, vibrating softly through the twilight, headed for their glade of dreams.

Subsequent visits to this glade emphasized the strength of association of this little fraternity, by realization of its temporal brevity. Three weeks after I first discovered the glade, I returned in late afternoon and waited silently. For a time I feared that the mariposal friendship was a thing of the past. But a few minutes before five the first Red-spot fluttered by, in and out among the twigs and leaves, as one slips an aeroplane through openings in drifting clouds. One by one, from all directions, the rest followed, until I counted twelve, twenty, thirty-four. Many of the twigs were now vacant, and most of the heliconias were tattered and forlorn, just able to keep at their fluttering level. There was something infinitely pathetic in this little company, which in less than a month had become so out at elbow, so aged, with death close ahead, yet with all their remaining strength making their way from north and from south, from dense and from open jungle, to keep tryst for this silent, somnolent communion. I rose quietly and passed carefully from the glade, disturbing none of the paper-thin silhouettes, so like the foliage in outward seeming, yet so individual, each perhaps with dim dreams of flowers and little meetings and wind tossings; certainly with small adventures awaiting their awakening on the morrow, and a very certain kismet such a short way ahead.

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.

IX

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 antennæ, 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 antennæ. 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.