Chapter III: Front Matter (3)

A book could be written upon burning leaves--how they meet their cremation, how they curl when this new, devastating long-bottled-up sun heat chars their tissues. How they shout and crack in the wind of their own swan song, and how they look when the heat and roar have passed and the cold ash remains. A month of drought at Kartabo once made the thick mat of bamboo leaves about the compound considerable of a menace. So we had a great raking and bonfire of the ten million and one elongated slivers of pale brown leaves. (Even the color of dead leaves, like the plumage of hen pheasants, is far more subtle and beautiful than we suspect, for after the above sentence, I try to match a dead bamboo leaf color in Ridgway’s color book and fail utterly. It lies between vinaceous-buff and olive-buff and is of no human-named color.)

The ashy souls of leaves differ to as great a degree as do their shapes and life-greens. Some are so ethereal that they vanish in a curl of faint blue smoke and leave scarcely a trace of ponderable greyness. The bamboos are far otherwise. There is nothing quiet or sad about their cremation. They snap and crackle joyously in the flames, with more gust than ever they rattled in the trade winds. And indeed their passing is far less of a radical change than for most leaves. They are so surcharged with silica that the alchemy of glowing heat merely alters their hue to silvery white, and when the furnace of their tissues has cooled, they lie unchanged in shape and outline. A heavy rain or big wind shatters this crystalline ghost of a _feuille_, and the various salts are washed into the soil, ready for their next great adventure.

Before I lived under bamboos I never realized how friendly fallen leaves could be. Trees with heavy, leaded-stemmed leaves drop them straight to the ground. But bamboo leaves are like zeppelins when they are launched and, with the slightest breeze float along on even keels, drifting sometimes far into the laboratory. When at tea one day I idly watched a leaf dangling high up from one of the lofty stems, so far away I could not tell whether it was brown or green. A slight gust came and it broke off and, revolving slowly, scaled obliquely down, through the verandah and launched in my teacup.

These leaves register very accurately the force of the wind, and I have seen a thick bed of ashes of burned bamboo leaves studded thickly as a porcupine’s skin with the javelins of recent falls, two lots having speared the ashes at different angles. One was almost upright, having landed in a gentle wind that afternoon, the other at an oblique angle, after volplaning on the stronger trades of morning.

Leaves in death still mirror many of the characteristics of their living fellows. In the tropics a host of plants flower once or at most twice a year, but attract insects at all times by setting forth a little bowl of nectar on each leaf stalk. I have observed a small bush with forty-nine leaves and counted nine and forty ants thereon, one guest to each nectar-cup,--each having visited, sipped and remained--perhaps by their jealous gormandizing keeping away other more harmful insects. On fallen leaves the sides of the bowls still seem to contain some sweetness, and to these come other ants (as we used to love to scrape the emptied ice-cream freezer), who gnaw eagerly at the shrivelled cups and the sweet crusts which have fallen from the table of the jungle.

There are parts of jungle clearings which I hardly know in early morning, while their foliage is still asleep. Some leaves are surprisingly drowsy and not until the sun actually fillips them with its beams do they raise their heads, twist on their stalks in a leafy yawn, and eat to their daily stint in their chlorophyll factory. These leaves die in the position of sleep, so that if we had a fallen twigful we would know their somnolent attitude in life.

By far the phase of dominant interest in fallen or dead leaves is the part they have played in the evolution of animal life. If we can infer the position of sleep from that in death, how vastly greater is possible the reconstruction of dead vegetation from living creatures of the jungle. If every leaf and twig, flower and fruit, branch and trunk were to vanish suddenly from the earth, their memory would remain deeply impressed in form, size, movement, pattern and color of a host of creatures, while we would still have even the jungle lights and shadows etched upon fur and feathers. As we go down the scale in life we find more and more marvels of resemblance, and it would be an easy matter to reconstruct an entire plant of animals. I have caught monster walking-stick insects over a foot in length, which were dead wood to the keenest eye. Smaller ones carry the resemblance to an inordinate extreme. Not only do they look like twigs and stems, but they _act_ like them, clinging with four feet and dangling the other two out in midair, while every now and then the whole insect sways gently, as does a tiny twig moved by a breath. Things such as this make a scientist’s work wonderful and holy beyond Bryan’s utmost conception of these words.

From day to day in the jungle I add to my animal-plants. I discover giant katy-dids so green and flat, so veined and stemmed, that no passing observer could say, “This is leaf, this insect.” Others have spoiled the symmetry and perfection of their sham chlorophyll with simulated holes, and apparent tears and spots of fungi, and the droppings of birds. All the diseases, parasites and injuries of leaves have been photographed upon the wings of insects, in unconscious endeavor to escape observation. At this point we come upon interactions, complications, subtleties of great delicacy, such as are shown by mantids, or “rar’hor’ses” as they are called in the Southern States. These are incarnated, material sophists, camouflaged under chlorophyll color not for protection but for attack. As the white fox creeps upon the white ptarmigan over the white snow, so here in the tropics, the mantids re-enact a similar, but viridescent drama.

Passing on from growing leaves we find flower bugs and orchid spiders, the latter being forced to conceal their brilliant pigments in the shadow of under-leaf, until some particular blossom appears. Then, with their colors and patterns so exact that they might have been fashioned in the same petal shop the spiders take their place on or near the flowers. Some even eat away the heart of the blossom, substituting their stamen leg and pistil palpi, and with the unharmed nectary still giving forth perfume, these deadly frauds of flowers await the visiting bees.

Caterpillars gnaw out bits of leaf and then fill up the space with their own painted bodies, but butterflies and moths are the veritable reflections of leaves, they would indeed be naked and blatant to the world were foliage to vanish. Here again not only are color and pattern invoked but even the movement in falling. I have had a brown butterfly flutter in short, oblique eddies to my feet, and there alight warelessly and sway from side to side. Dozens of times I have crept up and enmeshed a dead leaf in my net, and as many times have brushed heedlessly by a dead leaf only to have it take wings to itself and fly away.

Two adventures which befell me yesterday had to do with leaves, and touched the extremes of the gamut of an explorer’s life--from the danger of death to the glory of new discovery. Every morning a bird had been calling from a certain tree-top--a short, raucous, unpleasant call, but a new one. So ventriloquil was it that it had wholly baffled me. Only by triangulation, the successive focussing from three distant points, could I ever hope to find it. I was creeping slowly on my second lap, lifting my feet high to clear twigs and vines, when something drew my eyes from the tree overhead to the dead leaves below. This has happened to me perhaps a score of times and I hope will continue in the future--the sudden, inexplicable perception of a poisonous snake on which my foot is about to descend. A large fer-de-lance, more like dead leaves than the leaves themselves, was coiled less than two feet away. On its scales it mirrored the brown dead leaves, the dark fungus spots, the shadows of the curled-up edges, the high lights of the burnished surface sheen. Optically there was no interruption of the floor of dead foliage; actually a horrible death lay twelve inches beneath my upraised foot. The lethal mat was coiled as evenly as a rope on a battleship and in the exact center lay the arrow head with its unwinking eyes and the flickering tongue. As I withdrew my foot and began to breathe again, I forgot my raucous-voiced bird and sat down to ponder this. I took my strong butterfly net and drew the netting taut across the ring and behind this barrier I slowly approached. Closer and closer I drew until I could see the slit-like pupil and the green and livid mottling of the iris. When I almost touched the sharp snout with the other side of the mesh, I sniffed carefully and repeatedly, dulling every other sense but that of smell. There came to my nostrils a faint but distinct odor, an unpleasant musk, which, once detected, remained vivid. It was a faint adumbration of that strong, repulsive smell which permeates the cage where one of these reptiles is confined, and I believe that, without invoking any more radically psychic process, my attention is attracted and focussed at these times by the faint, unconsciously stimulating odor of the snake on the jungle floor. I cannot otherwise explain my invariable detection at the last minute, of creatures who more than any others are of the leaves, leafy.

My second adventure was also a thrilling one but from a wholly different point of view. I was walking along a trail after a shower, looking idly at a big, palmated leaf at my very elbow when there suddenly materialized upon it a large lizard. It was one of the most beautiful of all lizards and fortunately had been named with imagination--_Polychrus marmoratus_--the many-colored Marble One. It was sprawled flat upon the great green expanse, its scales shimmering leaf-green with enough spots here and there to be a convincing portion of the full-grown, insect-defaced foliage. I leaned toward it and it began slowly to creep away. The long, slender tail was curled and twisted into a lifeless tendril, and the toes dangled half in midair like no imaginable piece of any live reptile. Progress was by means of the forefeet alone, one after the other being pushed ahead stealthily, taking hold and dragging the rest of the creature onward. The body, hind legs and tail simply scraped over the leaf.

When it reached the thick, brown twig, magic began before our eyes--for fortunately I had two companions to share this wonder. As it left the green tissue and crawled slowly out along the twig its course was traceable not only by its position in space, but by most exquisitely adjusted and timed pigmental change,--at the exact edge of the leaf the green gradually faded and a wave of brown swept down the reptile. Never have I seen a more perfect use of obliterative color. In captivity these polychrus will often run through their whole little palatal gamut from mere emotion, or light and shadow. The whole soul of my lizard on the leaf was concentrated in his half-closed eyes watching my every motion, yet it must have been through the eye alone that the amazingly accurate somatic color change was dictated and regulated. Here was surely the ultimate example of vegetable imitation, twigs, leaves--both green and brown--tendril swaying movement, all in one organism. Not for anything would I have betrayed the lizard’s trust in the magnificent shield which nature had built up about it. We pretended to be completely deceived and left it--an irregular bit of half-greenness on the second leaf, and half brownness on the twig.

A classic volume will some day be written on the adventures of fallen leaves, for when a leaf has evaded the inroads of insects and fungi, has resisted wind and rain, succumbing finally to the pull of gravitation, there awaits it, in addition to ultimate mold and desiccation, a host of possible adventures on the jungle floor.

With all my desire to clothe the fallen leaf with dramatic interest and an abstract vitality, my first and last thoughts are those of sadness. Alien as I am to these tropical jungles, a mere transient injection from the North, the sear and yellow leaf means to me the end of a season, of a year--a very appreciable fraction of lifetime--and even in this evergreen land, this jungle _de le printemps éternel_, the dead leaf eddying to earth is a sad and a tragic happening.

V

THE JUNGLE SLUGGARD

Sloths have no right to be living on the earth today; they would be fitting inhabitants of Mars, where a year is over six hundred days long. In fact they would exist more appropriately on a still more distant planet where time--as we know it--creeps and crawls instead of flies from dawn to dusk. Years ago I wrote that sloths reminded me of nothing so much as the wonderful Rath Brother athletes or of a slowed-up moving picture, and I can still think of no better similes.

Sloths live altogether in trees, but so do monkeys, and the chief difference between them would seem to be that the latter spend their time pushing against gravitation while the sloths pull against it. Botanically the two groups of animals are comparable to the flower which holds its head up to the sun, swaying on its long stem, and, on the other hand, the over-ripe fruit dangling heavily from its base. We ourselves are physically far removed from sloths--for while we can point with pride to the daily achievement of those ambulatory athletes, floor-walkers and policemen, yet no human being can cling with his hands to a branch for more than a comparatively short time.

Like a rainbow before breakfast, a sloth is a surprise, an unexpected fellow breather of the air of our planet. No one could prophesy a sloth. If you have an imaginative friend who has never seen a sloth and ask him to describe what he thinks it ought to be like, his uncontrolled phrases will fall far short of reality. If there were no sloths, Dunsany would hesitate to put such a creature in the forests of Mluna, Marco Polo would deny having seen one, and Munchausen would whistle as he listened to a friend’s description.

A scientist--even a taxonomist himself--falters when he mentions the group to which a sloth belongs. A taxonomist is the most terribly accurate person in the world, dealing with unvarying facts, and his names and descriptions of animals defy discretion, murder imagination. Nevertheless when next you see a taxonomist disengaged, approach him boldly and ask him in a tone of quarrelsome interest to what order of Mammalia sloths belong. If an honest conservative he will say, “Edentata,” which, as any ancient Greek will tell you, means a toothless one. Then if you wish to enrage and nonplus the taxonomist, which I think no one should, as I am one myself, then ask him Why? or, if he has ever been bitten by any of the eighteen teeth of a sloth?

The great savant Buffon in spite of all his genius, fell into most grievous error in his estimation of a sloth. He says, “The inertia of this animal is not so much due to laziness as to wretchedness; it is the consequence of its faulty structure. Inactivity, stupidity, and even habitual suffering result from its strange and ill-constructed conformation. Having no weapons for attack or defense, no mode of refuge even by burrowing, its only safety is in flight.... Everything about it shows its wretchedness and proclaims it to be one of those defective monsters, those imperfect sketches, which Nature has sometimes formed, and which, having scarcely the faculty of existence, could only continue for a short time and have since been removed from the catalogue of living beings. They are the last possible term amongst creatures of flesh and blood, and any further defect would have made their existence impossible.”

If we imagine the dignified French savant himself, naked, and dangling from a lofty jungle branch in the full heat of the tropic sun, without water and with the prospect of nothing but coarse leaves for breakfast, dinner and all future meals, an impartial onlooker who was ignorant of man’s normal haunts and life could very truthfully apply to the unhappy scientist, Buffon’s own comments. All of his terms of opprobrium would come home to roost with him.

A bridge out of place would be an absolutely inexplicable thing, as would a sloth in Paris, or a Buffon in the trees. As a matter of fact it was only when I became a temporary cripple myself that I began to appreciate the astonishing lives which sloths lead. With one of my feet injured and out of commission I found an abundance of time in six weeks to study the individuals which we caught in the jungle near by. Not until we invent a superlative of which the word “deliberate” is the positive can we define a sloth with sufficient adequateness and briefness. I dimly remember certain volumes by an authoress whose style pictured the hero walking from the door to the front gate, placing first the right, then the left foot before him as he went. With such detail and speed of action might one write the biography of a sloth.

Ever since man has ventured into this wilderness, sloths have aroused astonishment and comment. Four hundred years ago Gonzala de Oviedo sat him down and penned a most delectable account of these creatures. He says, in part: “There is another strange beast the Spaniards call the Light Dogge, which is one of the slowest beasts and so heavie and dull in mooving that it can scarsely goe fiftie pases in a whole day. Their neckes are high and streight, and all equall like the pestle of a mortar, without making any proportion of similitude of a head, or any difference except in the noddle, and in the tops of their neckes. They have little mouthes, and moove their neckes from one side to another, as though they were astonished: their chiefe desire and delight is to cleave and sticke fast unto Trees, whereunto cleaving fast, they mount up little by little, staying themselves by their long claws. Their voice is much differing from other beasts, for they sing only in the night, and that continually from time to time, singing ever six notes one higher than another. Sometimes the Christian men find these beasts, and bring them home to their houses, where also they creepe all about with their natural slownesse. I could never perceive other but that they love onely of Aire: because they ever turne their heads and mouthes toward that part where the wind bloweth most, whereby may be considered that they take most pleasure in the Aire. They bite not, nor yet can bite, having very little mouthes: they are not venemous or noyous any way, but altogether brutish, and utterly unprofitable and without commoditie yet known to men.”

It is difficult to find adequate comparisons for a topsy-turvy creature like a sloth, but if I had already had synthetic experience with a Golem, I would take for a formula the general appearance of an English sheep dog, giving it a face with barely distinguishable features and no expression, an inexhaustible appetite for a single kind of coarse leaf, a gamut of emotions well below the animal kingdom, and an enthusiasm for life excelled by a healthy sunflower. Suspend this from a jungle limb by a dozen strong hooks, and--you would still have to see a live sloth to appreciate its appearance.

At rest, curled up into an arboreal ball, a sloth is indistinguishable from a cluster of leaves; in action, the second hand of a watch often covers more distance. At first sight of the shapeless ball of hay, moving with hopeless inadequacy, astonishment shifts to pity, then to impatience and finally, as we sense a life of years spent thus, we feel almost disgust. At which moment the sloth reaches blindly in our direction, thinking us a barren, leafless, but perhaps climbable tree, and our emotions change again, this time to sheer delight as a tiny infant sloth raises its indescribably funny face from its mother’s breast and sends forth the single tone, the high, whistling squeak, which in sloth intercourse is song, shout, converse, whisper, argument and chant. Separating him from his mother is like plucking a bur from one’s hair, but when freed, he contentedly hooks his small self to our clothing and creeps slowly about.

Instead of reviewing all the observations and experiments which I perpetrated upon sloths, I will touch at once the heart of their mysterious psychology, giving in a few words a conception of their strange, uncanny minds. A bird will give up its life in defending its young; an alligator will not often desert its nest in the face of danger; a male stickleback fish will intrepidly face any intruder that threatens its eggs. In fact, at the time when the young of all animals are at the age of helplessness, the senses of the parents are doubly keen, their activities and weapons are at greatest efficiency for the guarding of the young and the consequent certainty of the continuance of their race.

The resistance made by a mother sloth to the abstraction of its offspring is chiefly the mechanical tangling of the young animal’s tiny claws in the long maternal fur. I have taken away a young sloth and hooked it to a branch five feet away. Being hungry it began at once to utter its high, penetrating penny whistle. To no other sound, high or low, with even a half tone’s difference does the sloth pay any heed, but its dim hearing is attuned to just this vibration. Slowly the mother starts off in what she thinks is the direction of the sound. It is the moment of moments in the life of the young animal. Yet I have seen her again and again on different occasions pass within two feet of the little chap, and never look to right or left, but keep straight on, stolidly and unvaryingly to the high jungle, while her baby, a few inches out of her path, called in vain. No kidnapped child hidden in mountain fastness or urban underworld was ever more completely lost to its parent than this infant, in full view and separated by only a sloth’s length of space.

A gun fired close to the ear of a sloth will usually arouse not the slightest tremor; no scent of flower or acid or carrion causes any reaction; a sleeping sloth may be shaken violently without awakening, the waving of a scarlet rag, or a climbing serpent a few feet away brings no gleam of curiosity or fear to the dull eyes; an astonishingly long immersion in water produces discomfort but not death. When we think what a constant struggle life is to most creatures, even when they are equipped with the keenest of senses and powerful means of offense, it seems incredible that a sloth can hold its own in this overcrowded tropical jungle.

From birth to death it climbs slowly about the great trees, leisurely feeding, languidly loving, and almost mechanically caring for its young. On the ground a host of enemies await it, but among the higher branches it fears chiefly occasional great boas, climbing jaguars and, worst of all, the mighty talons of harpy eagles. Its means of offense is a joke--a slow, ineffective reaching forward with open jaws, a lethargic stroke of arm and claws which anything but another sloth can avoid. Yet the race of sloths persists and thrives, and in past years I have had as many as eighteen under observation at one time.

A sloth makes no nest or shelter; it even disdains the protection of dense foliage. But for all its apparent helplessness it has a _cheval-de-frise_ of protection which many animals far above it in intelligence might well envy. Its outer line of defense is invisibility--and there is none better, for until you have seen your intended prey you can neither attack nor devour him. No hedgehog or armadillo ever rolled a more perfect ball of itself than does a sloth, sitting in a lofty, swaying crotch with head and feet and legs all gathered close together inside. This posture, to an onlooker, destroys all thought of a living animal, but presents a very satisfactory white ants’ nest or bunch of dead leaves. If we look at the hair of a sloth we will see small, grey patches along the length of the hairs--at first sight bits of bark and débris of wood. But these minute, scattered particles are of the utmost aid to this invisibility. They are a peculiar species of alga or lichen-like growth which is found only in this peculiar haunt, and when the rains begin and all the jungle turns a deep, glowing emerald, these tiny plants also react to the welcome moisture and become verdant--thus throwing over the sloth a protecting, misty veil of green.

Even we dull-sensed humans require neither sight nor hearing to detect the presence of an animal like the skunk; in the absolute quiet and blackness of midnight we can tell when a porcupine has crossed our path, or when there are mice in the bureau drawers. But a dozen sloths may be hanging to the trees near at hand and never the slightest whiff of odor comes from them. A baby sloth has not even a baby smell, and all this is part of the cloak of invisibility. The voice, raised so very seldom, is so ventriloquil, and possesses such a strange, unanimal-like quality that it can never be a guide to the location much less to the identity of the author. Here we have three senses, sight, hearing, smell, all operating at a distance, two of them by vibrations, and all leagued together to shelter the sloth from attack.

But in spite of this dramatic guard of invisibility the keen eyes of an eagle, the lapping tongue of a giant boa, and the amazing delicacy of a jaguar’s sense of smell break through at times. The jaguar scents sign under the tree of the sloth, climbs eagerly as far as he dares and finds ready to his paw the ball of animal unconsciousness; a harpy eagle half a mile above the jungle sees a bunch of leaves reach out a sleepy arm and scratch itself--something clumps of leaves should not do. Down spirals the great bird, slowly, majestically, knowing there is no need of haste, and alights close by the mammalian sphere. Still the sloth does not move, apparently waiting for what fate may bring--waiting with that patience and resignation which comes only to those of our fellow creatures who cannot say, “I am I!” It seems as if Nature had deserted her jungle changeling, stripped now of its protecting cloak.

The sloth however has never been given credit for its powers of passive resistance, and now, with its enemy within striking distance, its death or even injury is far from a certainty. The crotch which the sloth chooses for its favorite outdoor sport, sleep, is unusually high up or far out among the lesser branches, where the eight claws of the eagle or the eighteen of a jaguar find but precarious hold. In order to strike at the quiescent animal the bird has to relinquish half of its foothold, the cat nearly one quarter. If the victim were a feathery bush turkey or a soft-bodied squirrel, one stroke would be sufficient, but this strange creature is something far different. In the first place it is only to be plucked from its perch by the exertion of enormous strength. No man can seize a sloth by the long hair of the back and pull it off. So strong are its muscles, so vise-like the grip of its dozen talons that either the crotch must be cut or broken off or the long claws unfastened one by one. Neither of these alternatives is possible to the attacking cat or eagle. They must depend upon crushing or penetrating power of stroke or grasp.

Here is where the sloth’s second line of defense becomes operative. First, as I have mentioned, the swaying branch and dizzy height is in his favor, as well as his immovable grip. To begin with the innermost defenses, while his jungle fellows, the ring-tailed and red howling monkeys, have thirteen ribs, the sloth may have as many as twenty; in the latter animal they are, in addition, unusually broad and flat, slats rather than rods. Next comes the skin which is so thick and tough that many an Indian’s arrow falls back without even scratching the hide. The skin of the unborn sloth is as tough and strong as that of a full-grown monkey. Finally we have the fur--two distinct coats, the under one fine, short and matted, the outer long, harsh and coarse. Is it any wonder that, teetering on a swaying branch, many a jaguar has had to give up after frantic attempts to strike his claws through the felted hair, the tough skin and the bony lattice-work which protect the vitals of this Edentate bur!

Having rescued our sloth from his most immediate peril let us watch him solve some of the very few problems which life presents to him. Although the cecropia tree, on the leaves of which he feeds, is scattered far and wide through the jungle, yet sloths are found almost exclusively along river banks, and, most amazingly, they not infrequently take to the water. I have caught a dozen sloths swimming rivers a mile or more in width. Judging from the speed of short distances, a sloth can swim a mile in three hours and twenty minutes. Their thick skin and fur must be a protection against crocodiles, electric eels and perai fish as well as jaguars. Why they should ever wish to swim across these wide expanses of water is as inexplicable as the migration of butterflies. One side of the river has as many comfortable crotches, as many millions of cecropia leaves and as many eligible lady sloths as the other! In this unreasonable desire for anything which is out of reach sloths come very close to a characteristic of human beings.

Even in the jungle sloths are not always the static creatures which their vegetable-like life would lead us to believe, as I was able to prove many years ago. A young male was brought in by Indians and after keeping it a few days I shaved off two patches of hair from the center of the back, and labelling it with a metal tag I turned it loose. Forty-eight days later it was captured near a small settlement of bovianders several miles farther up and across the river. During this time it must have traversed four miles of jungle and one of river.

The principal difference between the male and female three-toed sloths is the presence on the back of the male of a large, oval spot of orange-colored fur. To any creature of more active mentality such a minor distinction must often be embarrassing. In an approaching sloth, walking upside-down as usual, this mark is quite invisible, and hence every meeting of two sloths must contain much of delightful uncertainty, of ignorance whether the encounter presages courtship or merely gossip. But color or markings have no meaning in the dull eyes of these animals. Until they have sniffed and almost touched noses they show no recognition or reaction whatever.

I once invented a sloth island--a large circle of ground surrounded by a deep ditch, where sloths climbed about some saplings and ate, but principally slept, and lived for months at a time. This was within sight of my laboratory table, so I could watch what was taking place by merely raising my head. Some of the occurrences were almost too strange for creatures of this earth. I watched two courtships, each resulting in nothing more serious than my own amusement. A female was asleep in a low crotch, curled up into a perfect ball deep within which was ensconced a month-old baby. Two yards overhead was a male who had slept for nine hours without interruption. Moved by what, to a sloth, must have been a burst of uncontrollable emotion, he slowly unwound himself and clambered downward. When close to the sleeping beauty he reached out a claw and tentatively touched a shoulder. Even more deliberately she excavated her head and long neck and peered in every direction but the right one. At last she perceived her suitor and looked away as if the sight was too much for her. Again he touched her post-like neck, and now there arose all the flaming fury of a mother at the flirtatious advances of this stranger. With incredible slowness and effort she freed an arm, deliberately drew it back and then began a slow forward stroke with arm and claws. Meanwhile her gentleman friend had changed his position so the blow swept, or, more correctly passed, through empty air, the lack of impact almost throwing her out of the crotch. The disdained one left with slowness and dignity--or had he already forgotten why he had descended?--and returned to his perch and slumber, where I am sure, not even such active things as dreams came to disturb his peace.

The second courtship advanced to the stage where the Gallant actually got his claws tangled in the lady’s back hair before she awoke. When she grasped the situation she left at once and clambered to the highest branch tip followed by the male. Then she turned and climbed down and across her annoyer, leaving him stranded on the lofty branch looking eagerly about and reaching out hopefully toward a big, green iguana asleep on the next limb in mistake for his fair companion. For an hour he wandered languidly after her, then gave it up and went to sleep. Throughout these and other emotional crises no sound is ever uttered, no feature altered from its stolid repose. The head moves mechanically and the dull eyes blink slowly, as if striving to pierce the opaque veil which ever hangs between the brain of a sloth and the sights, sounds and odors of this tropical world. If the orange back spot was ever of any use in courtship, in arousing any emotion æsthetic or otherwise, it must have been in ages long past when the ancestors of sloths, contemporaries of their gigantic relatives the Mylodons, had better eyesight for escaping from sabre-toothed tigers, than there is need today.

The climax of a sloth’s emotion has nothing to do with the opposite sex or with the young, but is exhibited when two females are confined in a cage together. The result is wholly unexpected. After sniffing at one another for a moment, they engage in a slowed-up moving-picture battle. Before any harm is done one or the other gives utterance to the usual piercing whistle and surrenders. She lies flat on the cage floor and offers no defense while the second female proceeds to claw her, now and then attempting, usually vainly, to bite. It is so unpleasant that I have always separated them at this stage, but there is no doubt that in every case the unnatural affray would go on until the victim was killed. In fact I have heard of several instances where this actually took place.

A far pleasanter sight is the young sloth, one of the most adorable balls of fuzzy fur imaginable. While the sense of play is all but lacking his trustfulness and helplessness are most infantile. Every person who takes him up is an accepted substitute for his mother and he will clamber slowly about one’s clothing for hours in supreme contentment. One thing I can never explain is that on the ground the baby is even more helpless than his parents. While they can hitch themselves along, body dragging, limbs outspread, until they reach the nearest tree, a young sloth is wholly without power to move. Placed on a flat bit of ground it rolls and tumbles about, occasionally greatly encouraged by seizing hold of its own foot or leg under the impression that at last it has encountered a branch.

Sloths sleep about twice as much as other mammals and a baby sloth often gets tired of being confined in the heart of its mother’s sleeping sphere, and creeping out under her arm will go on an exploring expedition around and around her. When over two weeks old it has strength to rise on its hind legs and sway back and forth like nothing else in the world. Its eyes are only a little keener than those of the parent and it peers up at the foliage overhead with the most pitiful interest. It is slowly weaned from a milk diet to the leaves of the cecropia which the mother at first chews up for her offspring.

I once watched a young sloth about a month old and saw it leave its mother for the first time. As the old one moved slowly back and forth, pulling down cecropia leaves and feeding on them, the youngster took firm grip on a leaf stem, mumbling at it with no success whatever. When finally it stretched around and found no soft fur within reach it set up a wail which drew the attention of the mother at once. Still clinging to her perch, she reached out a forearm to an unbelievable distance and gently hooked the great claws about the huddled infant, which at once climbed down the long bridge and tumbled headlong into the hollow awaiting it.

When a very young sloth is gently disentangled from its mother and hooked on to a branch something of the greatest interest happens. Instead of walking forward, one foot after the other, and upside-down as all adult sloths do, it reaches up and tries to get first one arm then the other _over_ the support, and to pull itself into an upright position. This would seem to be a reversion to a time--perhaps millions of years ago--when the ancestors of sloths had not yet begun to hang inverted from the branches. After an interval of clumsy reaching and wriggling about, the baby by accident grasps its own body or limb, and, in this case, convinced that it is at last anchored safely again to its mother, it confidently lets go with all its other claws and tumbles ignominiously to the ground.

The moment a baby sloth dies and slips from its grip on the mother’s fur, it ceases to exist for her. If it could call out she would reach down an arm and hook it toward her, but simply dropping silently means no more than if a disentangled bur had fallen from her coat. I have watched such a sloth carefully and have never seen any search of her own body or of the surrounding branches, or a moment’s distraction from sleep or food. An imitation of the cry of the dead baby will attract her attention, but if not repeated she forgets it at once.

It is interesting to know of the lives of such beings as this--chronic pacifists, normal morons, the superlative of negative natures, yet holding their own amidst the struggle for existence. Nothing else desires to feed on such coarse fodder, no other creature disputes with it the domain of the under side of branches, hence there is no competition. From our human point of view sloths are degenerate; from another angle they are among the most exquisitely adapted of living beings. If we humans, together with our brains, fitted as well into the possibilities of our own lives we should be infinitely finer and happier,--and, besides, I should then be able to interpret more intelligently the life and the philosophy of sloths!

VI

MANGROVE MYSTERY

One day I found a hammock-form of roots, a maze of gentle curves which gave and braced, and, taking paper, looked to see if a mangrove had anything of interest to offer. At the end of three hours I slid painfully down into the rising tide, my unpenciled sheet fluttered off, and I went away with my mind in a whirl.

I rejoiced in Barnum’s Circus long before I learned to write, but, if the first time thereafter, my mother had given me pencil and notebook with instructions to describe everything that took place in all three rings and on the stage, as well as the freaks, side shows and menagerie, my ideas would have been of equal clarity and inclusiveness as at my first mangrove séance. Above, around, beneath were interlacing trapezes, flying rings and rope ladders, liana nets and gaily painted poles, waving banners of emerald strung along the rafters, and high over all the canvas of the sky. And everywhere the performers--acrobats and leapers--worked mighty feats of balance and of strength; whiffs arose of strange and unknown creatures; thrilling, tuning-up squeaks and umpahs came from hidden orchestras which surely soon must burst forth in full fanfare of breath-shortening music. Now and then a being would creep slowly past, (doubtless on his weary way to a long parade about some invisible arena), of such sight and form, that if raised to man’s height would be a side show in himself.

But even at the first confusing survey, the mangrove stood out vivid and clear-cut. It had the aspect of a god, an Atlas, with feet firm planted upon earth, regardless whether currents of water or winds of air swirled about its knees, and with wide arms out--upward spread to the sky, upon which thousands of weaker beings found sanctuary. Some alighted for temporary rest of weary wings, others for longer periods, day boarders who came for meals or season residents who built their houses and reared their families upon the vibrant roots. And finally were those who knew no other world or scene, but, born or hatched upon the mangroves, clung to them until loosed by death. By their little body dropping to the water, they paid their final debt to Gravitation, returning to his implacable coffers this small meed of elevation-energy, which by grip of tendrils or of fingers they had possessed throughout their lives.

These were all kindly, or at most indifferent folk, who if they gave nothing of value, did no harm. In a circus, the smiling faces of two acrobats who catch one another in midair may mask bitter hatred, a desire to swing short, or grip loosely; the story writers are fond of showing us the tragic sorrow obverse of the clown’s grinning visage. In the sunshine and warmth of the mangrove tangle, behind the swaying leaves and bee-beckoning blossoms’ fragrance is terrible strife and slow death. The splendid plant gives shelter and support upon its sturdy uplifted arms, not only to the fairy homes of humming-birds, but to parasites whose gratitude is never to cease strangling with inflexible coils, or, more insidiously, gently to insert living threads of death into the very heart of their supporter. Out of all this, how futile it seems to try to give any real idea of the marvel of mangrove life. At most we can hope only to arouse a worthy discontent, a disquieting desire also to go and see. For here are living tales, complete but as yet unworded, worthy to fill volumes of Carroll or Dunsany or Barrie or Blackwood; here are scenes needing only paper tracing to equal the best of Rackham or Sime, to touch the emotional gamut of Böcklin and Heath Robinson.

About ten thousand years before I filled this fountain pen, some ancestor of yours and mine--our “touch of nature”--discovered that by building a house of piles out in a lake, he could thwart the wild animals which ever threatened him, and lessen the danger of a surprise attack from equally-to-be-dreaded envious or hasty-tempered neighbors. Few carnivores care to swim after their prey, and war canoes had hardly been invented. Such sanctuaries gave to families and to small tribes time to think, to invent new weapons, to seize new opportunities and to take better care of their babies.

Today, while pushing a canoe through the roots of the mangrove jungle, I thought enthusiastically of my pile-dwelling ancestors as I noted many exciting similes, and then paddled hastily back to the laboratory to see what botanists had thought about it. I found much of interest, but my mind was sobered, my imagination quieted. There was nothing of Swiss lake dwellings, but a very definite title of _Rhizophora Mangle_, and a casual remark of branches being supported by simple, vertical roots; it was put down that the petals were lacerate-woolly on the margin, exceeded by the calyx limb; but their delicate odor was passed by without comment; the living shifts of greens on the foliage, with the veins carrying shafts of parrot color over the background of pale chrysolite--this was ignored; to the botanist the leaves were leathery, quite entire, obovate-lanceolate and blunt--a statement unquestionably to the point. Finally I learned that the astringent bark is employed for tanning, and I returned to my living mangroves, alias R. Mangle, wondering if too constant pondering upon astringent, unadulterated facts is not often efficacious in a sort of mental tanning. Our mangrove might yield a new harvest to us if we could choose a different contact of thought, clothing the fruit with the vital interest hidden in “one-seeded by abortion,” and yet avoiding sentimental pleonasms.

However we decide to think of this plant, it is sure to be with admiration, for it stands out as a pioneer. Among earthly vegetation the mangrove is an aristocrat, a true dicotyledon, but it has dared to seek again the watery habitat of the lowlier growths, indeed of the very green algæ from which land plants originally developed. Like the penguin which has relinquished the ærial wing for an aquatic fin, or the seal which has encased its five fingers and five toes in flipper mittens, so the mangrove, while retaining all its badges of aristocracy, has returned to the haunts of the ancestors of all plants, from whence it can look calmly shoreward at the terrible struggle for life a few feet away, where every inch of soil is battled for, where the vigorous monopolize air and sunlight.

Such a radical change cannot be achieved without far-reaching adaptations and readjustments; the banker does not become a farmer merely by moving to the country, and every part of a mangrove shows delicate modes of meeting the strange new conditions as cunningly as the shift of muscles of a jiu-jitsu wrestler encountering an unknown opponent.

In the month of February, Kartabo mangroves are covered with flowers--and yet to a passing glance reveal no trace of inflorescence. Small and yellowish white, in irregular clusters of six to a dozen, they make no kind of visual showing, but their nectaries call to small trigonid bees in no uncertain way, and through the hours of sunlight the branches of the mangrove are busy marts of trade. Each cluster of blossoms becomes a corner grocery where the customers come for their buckets of nectars and packages of pollen and rush away without paying, or so they may think. But there are leaks in the pollen bags, and when they enter another blossom, the little stream of sifting yellow dust drifts across the entrance, a few grains or even a single one, falls upon the waiting pistil, and the bee has repaid for his bread and honey many fold and with compound interest. Its destiny fulfilled, the flower falls apart, the petal, lacerate-woolly margins and all, drifting off on the first tide. The ovary swells, two seeds form, and now comes the first adjustment, and we realize that in the botanist’s dry remark “one-seeded by abortion” may be concealed tragic doom and a wealth of subtle meaning. No spear can be thrown straight which has twin heads and shafts, and so one seed shrivels and dies, and the other thrives and grows. What decides the fate of life or death we do not know. Some delicate balance, some subtle test of worth or lack takes place in every one of the thousands upon thousands of fertilized mangrove blossoms, and there is no appeal. The reason, as we shall see, is too vital, the target too difficult and treacherous for a thought to be given to unborn plants.

The problem of the next generation of mangroves is a serious one. The seeds are formed over an everchanging surface; soft, sticky mud giving place to strong currents, flowing first in one, then in the opposite direction; rough waves plough up the mud and splash against the stilt-like roots. No sticky secretion, no mere weight, no hooks or ærial wings will suffice for these seeds. From their natal branch high above the tidal area, some sure method of anchorage must be found to enable them to avoid being smothered in the mud, stranded on the shore, rolled into deep water or washed out to sea.

The method is the arrow or loaded dart, and the force is the energy of gravitation stored in particle after particle by the mother plant, as she drew up salts and water and elements, raising them sapfully from mud and tide, and condensing them into a solid, slender, pointed weapon capable of coping with all the difficulties of the new environment. But no seed alone can thus function, and in solving this problem the mangrove reveals itself as one of the most remarkable plants in the world. The lower forms of vegetation form their seeds and thrust them forth naked upon the world; the more advanced plants ensheath their offspring in swaddling clothes of protection against heat and cold, moisture and aridity. These are comparable to egg-laying creatures, with yolk and shell to shield the embryo from dangers. But the mangrove is truly viviparous, and the embryo seed remains attached for months, nourished by the sap of the parent branch. Out of the pear-shaped head a root-like structure grows downward, often to a length of twenty inches and a width of one. Like an airplane bomb, or the deadly throwing assagai of the Zulus, the mangrove seedling is thickest three-fourths of the way down, and then tapers rapidly. With a weight of as much as three ounces and driving force generated by a height of twenty feet, the umbilical cord of sap may safely dry, the connecting sheath shrivel, and one day there is a dull little spatter of mud, or a splash of water, and the unconscious work of the bees, the months of slow invigorating by the parent plant are fulfilled. The seed sticks upright in the mud, propelled through even two feet of water to its goal, and immediately rootlets sprout and consolidate the anchorage.

I once blazed two dozen seedlings which seemed ready to drop, and three of these were loosed at low water, so that they fell unhindered directly into the mud. The others I missed and I can only surmise whether this is the rule; whether some subtle influence of moon or tide is not sufficient to cause the final separation. Such a stimulus would be of great value to the young plant and is no more improbable than the marvellous effect of the moon’s rays upon the palolo worms of the sea bottom.

Let us for awhile forget the mangrove circus medley,--crab clowns, strong men of the ants, hairy wild tarantulas, prestidigitator opossums producing ten infant opossums from a single fold of skin, white elephant membracid larvæ, living statue lianas, frog barkers and lightning change lizards. Let us think of birds, or of a single bird.

I have seen more than a hundred kinds of birds among the mangroves of Kartabo, but a mere enumeration of these would be of little value and of no interest. And instead of selecting the rarest, most bizarre of tropical forms, let us choose the commonest, the most blatant, apparently the most ordinary bird, with average habits and usual traits; which is another way of saying that we have observed it casually, watched it with unintelligent inattention, and wholly failed to interpret its activities in the terms of their desperate significance.