Part 11
“But if, retaining sense and sight, we could shrink into living atoms and plunge under water, of what a world of wonder would we form part. We would find this fairy kingdom peopled with the strangest creatures—creatures that swim with their hair, have ruby eyes blazing deep in their necks, with telescopic limbs that now are withdrawn wholly into their bodies and now stretched out to many times their own length. Here are some riding at anchor, moored by delicate threads spun out from their own toes. There are others flashing in glass armor, bristling with sharp spikes or ornamented with bosses and flowing curves; while fastened to a green stem is an animal convulvulus that by some invisible power draws a never-ceasing stream of victims into its gaping cup and tears them to death with hooked jaws deep down in its own body.”—_The Rotifera_ by C. T. Hudson and P. H. Goose, London, 1886.
The rotifers or wheel animalcules are fantastic creatures. They were first seen by the Dutchman Antonius van Leeuwenhoek, credited with being the inventor of the microscope. “On the 25th of August,” he wrote to the Royal Society of London with which group of savants patronized by Charles the Second he was in regular correspondence, “I saw in a leaden gutter on the front of the house for a length of five feet some rain water had been standing which had a red color. It occurred to me that this redness might be caused by red animalcules. I took a drop or two of the water and looked at it under the microscope.”
He found a confusion of “red-eyed monsters armed with teeth like those of the balance wheel of a watch, which appear to be projecting forward towards the head. They seem to whirl around with a very considerable velocity, by which means a rapid current of water is brought from a distance to the mouth of the creature who thereby is supplied with many invisible food particles.”
This discovery is of considerable significance in scientific history because, more than any of his previous findings, it caused the Amsterdam spectacle-maker to question the then widely held belief in the spontaneous generation of living things.
“They can,” he wrote the Royal Society in 1774, “continue many months out of water and be dry as dust, in which condition their shape is globular, the bigness exceeds not a grain of sand, and no signs of life appear. Notwithstanding, being put in water, the globule turns itself about, lengthens by slow degrees, becomes in the form of a lively maggot, and most commonly in a few minutes afterwards puts out its wheels and sweeps the water in search of food. But sometimes it may remain a long time in the maggot form and not show its wheels at all.”
Such tiny organisms capable of such long periods of suspended animation, Leeuwenhoek held, could be blown by the wind for long distances. Thus the sudden appearance of living animals in supposedly lifeless water did not indicate they had been born or created there.
The microscope designer had found, moreover, an hitherto unknown race, giants of the microscopic world and among the most fantastic of all animals—the rotifers.
These usually invisible animals with buzz-saws on their heads—the largest not more than a quarter-inch long and the majority less than a twentieth—seem to have gone further beyond life’s normally accepted frontiers than any other animals. One species lives comfortably in hot springs where temperatures go above 120 Fahrenheit. Others can be frozen in solid cakes of ice for weeks and show no ill effects. Sudden changes in temperature, however, often are fatal. On tops of Antarctic mountains projecting out of ice two miles thick, the little rotifers are found among sparse growths of lichens, the only animal life which approaches closely to the South Pole on land. There is no reason why they should not thrive in the hardly less hospitable mountains of Mars. They might have been carried there in light propelled earthdust.
The majority are fresh-water creatures. A few live in damp moss and a few species have obtained a foothold in the sea. Some live in immense colonies, permanently attached to stones. Some are free-living individualists who crawl like leeches, or swim rapidly. Some are parasites in the cells of water plants or in the gills of fresh water crabs. Others cling to floating plants or to water animals, to be carried from place to place. One highly social group lives in free-moving communities of forty or more individuals, attached to each other by their tail ends and radiating from a common center like wheel spokes. The usual color is reddish and most rotifers have one or more glittering red eyes. In a few cases these eyes are inside the bodies of transparent species.
Despite their minuteness, these predatory giants of the world invisible are highly developed animals. Each has a body divided, like that of a mammal, into three major segments—head, trunk, and extremities. In some the skin is hardened into an armor-like covering. Some have a panoply of defensive spines and bristles.
Inside the skin is a cavity full of watery fluid—it contains no corpuscles like blood—in which float the more important vital organs. In most animals there is tissue of some sort in which nerves, muscles, and glands are imbedded. In rotifers, however, there is very little of this connective tissue. Under a microscope one generally can see with some clearness each individual cell. These cells can be counted, for at the most there are only a few thousands, compared to the millions of millions that make up the bodies of larger animals. The muscles are not banded together, but consist of isolated strands whose job is to pull the head inside the armored trunk when faced with any threat, and to bend the body in various directions.
All rotifers have two organs unique to their race. First is the “buzz saw”. This is a crown of tentacles, quite similar in appearance under low magnification to a circular saw, which is constantly whirling. Its purpose is to create eddies in the water which will bring food particles to the mouth, a funnel-shaped opening on top of the head. In free-living species the saw may have some function as a propeller.
Second is the mastax, or “chewing stomach”. Every rotifer has two stomachs, one for masticating and one for digesting. The mouth opens directly into the first. It is provided with two horny, serrated jaws which crush toward each other and tear to bits the minute animals and plants which are the creature’s food. The jaws are provided with several hard parts, adapted for biting, crushing, holding, and tearing.
In the permanently anchored rotifers the rear of the body is prolonged into a stalk from the end of which a cement-like substance is secreted. This permanently attaches the animal to something, usually a stone. In some of the free-living forms the “foot” is replaced by one to twelve “leaping spines” by means of which the owner can spring suddenly forward several times its own length to capture an unsuspecting victim. This is most often some floating one-celled creature of the water-drop jungle, such as a protozoan elephant.
The male rotifer is usually much smaller than the female—sometimes nothing more than an appendage she carries about with her. The fantastic worlds of all sorts of rotifers are predominantly feminine worlds. For some species, in fact, males never have been found, but there is little doubt that they exist.
_Two-Headed Snakes Aren’t Rare_
Two-headed snakes probably are quite common. About 200 cases have been reported. Dr. Bert Cunningham of Duke University, who has studied several living specimens, has this to report about such snakes: “The heads play together, fight over a morsel of food even though it will go into the same stomach through either mouth, attempt to swallow one another, and sometimes fight fatal duels. Each head has a brain of its own. Few grow to any size. In this case two heads are not better than one, especially when they disagree when a second means escape or death.”
_Fantastic Sea Creatures_
Coral-forested waters around the Gilbert and Mariana Islands in the Pacific are yielding some of the most fantastic sea creatures known to science.
Extensive collections have been made since the war by Dr. Leonard P. Schultz, Smithsonian curator of fishes. Notable in the collections are snake, worm and moray eels, all bottom dwellers in tropical waters. Snake eels are, as the name indicates, superficially almost indistinguishable from serpents. On their tails they have hard points which are used as drills. They burrow straight downward in the bottom sand, tails first, until only the heads protrude above the surface. The worm eels belong to the same general group but are much smaller and slenderer—about the diameter of a lead pencil and reaching lengths up to two feet. Larger worm eels have been reported.
Both these groups consist of relatively timid, inoffensive creatures. Far different are the moray eels, members of a closely related family. They are as much as ten feet long, have razor-like teeth, and are described by Dr. Schultz as about the most vicious creatures in the sea. In disposition they probably are worse than the worst sharks and easily can bite through a man’s hand.
Probably the most poisonous creature in the collection is a variety of sting ray, weighing about 200 pounds, which was speared at the bottom of 20 feet of water. This animal, like all stingarees, has a tail armed with long, poisonous barbs. The venom could be lethal to a man. After it was speared, the ray remained very much alive and the problem of bringing it to the surface was difficult. This finally was accomplished by two of Dr. Schultz' collaborators. First one would dive, grasp the handle of the spear, and lift the creature a few feet, always holding it far enough away to be clear of the barbs. After the first man became exhausted, the other would relieve him while he came up for air. Thus the specimen finally was gotten on board through a series of relays.
Curiosities of the collection are the cardinal fishes—brilliant red, very active, and including some of the smallest marine fishes. A few species attain full growth at about three-fourths of an inch. These are the most notable of the “mouth breeders.” The female lays the eggs and the male carries them in his mouth until they hatch. Inch-long males sometimes carry as many as 400 eggs, nearly all of which hatch.
Other curiosities are the pipe fishes, hard-shelled animals which look like bits of small, segmented pipe. They range from two inches to a foot long and are related to the more familiar sea horses of temperate waters. They are sluggish burrowers in coral reefs. As among sea horses, the male gives birth to the young. The eggs are deposited in pouches on the male’s belly where they are carried until they hatch.
_The Varieties of Raven Language_
While “nevermore” apparently is not in the vocabulary of the raven this big black bird of the wilder parts of the country has a considerable variety of sounds nearly as ominous.
Raven “language” has been intensively studied by the noted ornithologist, Dr. Arthur Cleveland Bent. Citing various bird observers, he lists the following calls:
A distinct, hollow, sepulchral laugh, haw-haw-haw-haw, which may be heard at almost any time.
A series of “crawks” sounded while on the wing, interspersed with a musical note that sounds like ge-lick-ge-lee.
A strange call like thing-thung-thung which is similar to the mellow twang of a tuning fork.
Another expression has a metallic, liquid-like quality similar to the song of the red-winged blackbird, although greatly magnified in volume.
Ravens have a large range of notes from the melancholy croaks with which they chiefly are associated to striking imitations of other birds, such as geese and gulls. One of these birds will talk to itself for hours with a curious gargling sound. He becomes so absorbed in his own conversation that it often is not difficult to steal up on him during such a soliloquy.
“The raven,” Dr. Bent observes, “is one of our most sagacious birds—crafty, resourceful, adaptable, and quick to profit by experience. Throughout most of its range it is exceeding shy and wary. It is almost impossible to get within gunshot of one in the open. Yet it knows full well where and when it is safe. About northern villages, where it is appreciated as a scavenger and seldom molested, it is as tame as any barnyard bird.” This is especially true in Greenland where ravens infest American air bases.
Although in the north the raven frequents the seacoast and villages, from Pennsylvania southward it is entirely a mountain bird, usually living above 3,000 feet. From these heights the birds sometimes descend to the valleys, or even the islands along the coast, to forage among the colonies of sea birds. Most of them prefer to dwell among rocks and resort to perpendicular cliffs and to escarpments thrust above forests on the flanks of mountains.
_Worms With Hypodermic Needles_
Despite their microscopic size, nematodes (soil worms), are highly organized animals. They have muscles, quite specialized organs for feeding, a digestive system, a nervous system with a brain, and a well-developed reproductive system. Sexes are clearly differentiated. The creatures have evolved a long way from the primeval worm.
Eggs may be deposited in the soil, or in the plant on which the nematode feeds. In these eggs the immature forms, the larvae, develop and eventually hatch. If appropriate plants are available, they may begin to feed immediately. They develop through several distinct stages. At the end of each of these cycles a moult occurs.
Many of the forms which have been studied closely have a minimum life cycle, from egg to egg-laying female, of several days to several weeks. The maximum duration of life, however, may be much longer, since sexual maturity is not reached until the nematode begins to feed on the living plant. Up to this time it remains in the larval stage and lives on a reserve food supply originally derived from the egg. The time this reserve lasts depends on circumstances. In damp, warm soil the nematode will be very active and use it up in a few weeks. In cool or dry soil the supply lasts much longer, and can extend to many years.
The little worm’s life is a perpetual struggle for existence. It has many enemies in the soil—insects, fungi, and other free-living nematodes. Certain of the soil fungi have “traps” especially designed to catch nematodes. Some of these are shaped like loops which are pulled tight as the worm starts to crawl through. Others are sticky surfaces on which the victims are captured, like flies on flypaper. In either case, the fungus grows into the body of the worm and kills it.
Nevertheless, the nematode population is never in any great danger of extermination. A single female root knot nematode will produce about 300 eggs in a couple of weeks. Allowing four weeks for a generation, and assuming half the offspring are females, this implies a theoretically possible fifty trillion individuals at the end of the four generations of a single summer.
Practically all roots are attacked by some kind of nematode, but many species appear to specialize on one type of plant and will not touch a different variety, even if no other food is available. Plants immune to one species may be highly susceptible to some other. A few kinds of these worms, however, appear to eat almost anything they can find underground.
All the root-eaters have a feeding organ which is much like a hypodermic needle. This is pushed into the tissue and, it is believed, a digestive juice of some sort is injected. This liquifies and partially digests the food. Then the nematode sucks it through the needle into its mouth.
The largest of the nematodes, a parasite of whales, can reach a length of 27 feet. The smallest, a marine form, is a little more than a three-thousandth of an inch long.
_The Fatal Black Widow Spider_
The venom of the dreaded Black Widow spider is approximately fifteen times more potent than that of the rattlesnake. The comparison has been established by determining the amounts of rattlesnake and spider venom necessary to kill rats of the same weight. The extreme toxicity of the spider becomes of considerable significance since it has been reported from every state in the Union and may be increasing in numbers on the edges of cities. Probability of being bitten, however, is slight. The black widow is a timid creature, except towards her natural prey. At the first molestation of her web she retreats quickly to her central nest and does not venture out again for hours. She makes no attempt at defense, to say nothing of aggression. Her reputation is so bad, however, that in some cases pickers have refused to work in vineyards which she infested.
_Plants That are Animated_
Among the curiosities often sold in American stores are so-called “air plants”—plants that will grow on air alone without sunshine or water. This is true, after a fashion. The “plants” actually are dried skeletons of marine animals. They belong to the group which includes the jellyfish, sea anemones and corals. Their skeletons have a striking resemblance to plants.
The species most commonly sold is sea moss or Neptune’s fern, an animal abundant in the North Atlantic, especially in the English channel and the Gulf of Maine. A closely related species, the “squirrel’s tail,” is abundant in the eastern Pacific where its silvery colonies often are washed ashore by storms. Dry beach material of these colonies is easily collected, dyed and sold as Christmas decorations.
“These are colonial forms consisting of thousands of individual animals,” according to the Chicago Museum of Natural History. “Colonies of two species of sea squirrel may be twelve inches or more long. Those of some species may be several feet in length. Usually they are attached to rocks or other substrata by a rootlike base, from which spring the delicate branched stems bearing hundreds of minute polyps.
“Most of these are hydranths (feeding polyps) that capture microscopic organisms. The reproductive polyps are less common, usually larger, and different in shape. The common stem is made up of external non-cellular material, mostly yellowish or brown in color.”
_The Tomato—Cinderella of Vegetables_
A remarkable chapter in the history of agriculture is the story of the tomato which now constitutes one of this country’s major crops. It appears to have first been used as a food by the Aztecs. It was introduced into Spain early in the 16th century and a century later was grown widely in England as an ornamental plant. Not until the next century, however, did it have any standing as a food. It was known as the “love apple” and was considered mildly poisonous. Folks ate one now and then on “dares.”
Then it caught on as a food in Italy and by the start of the 19th century was being grown on a field scale. So far as known, it was absent from the gardens of Colonial America, unless as a rare ornamental plant. Not until the middle of the 19th century was it reintroduced to its native western hemisphere as a food crop. For a long time it acquired no great popularity. A few vines in the family garden were considered enough, since there was no tomato market.
A U. S. Department of Agriculture report calls the tomato “the prodigy of the vegetable world.” Its present success is due in large part to the discovery of vitamins. Although used as a food for little more than a century it now is almost as widely distributed as wheat, a food plant which has been cultivated for at least 5,000 years.
Today the tomato crop covers about a half million acres in the U. S. alone. This crop consists of more than 20,000,000 bushels of fresh tomatoes and more than 300,000 tons of canned products. There are now about 150 known varieties, adapted to all sorts of purposes.
_The Holiest Place on Earth_
The summit of Adam’s Peak in south-central Ceylon, wrapped perpetually in priestly robes of grey clouds, is one of the holy places of the earth. There, through many centuries, the prayers of millions belonging to warring creeds have worn thin the curtain between the effable and the ineffable. It is a shrine of four of the world’s great religions. In the rock is a depression that looks like a giant’s footprint. Hindus believe it was made by snake-haired Siva, the destroyer. Moslems say it is the footprint of the first man, Adam, who was exiled to this mountaintop after he was thrown out of Paradise. Buddhists believe that it could have been made only by the great Gautama. Nestorian Christians maintain that it is a relic of the disciple Thomas, who brought the gospel of Christ into the East. To this spot, braving the road through leech-infested forests below and the perilous ascent along gale-swept ledges, have come generation after generation of devout pilgrims to voice a common prayer in different tongues through different intermediaries.
The pilgrim, standing by the footprint of Adam, looks down upon the forest-covered hills to the eastward. Over all the land spreads the grey shadow of the supernatural. Below him is one of the most imposing spectacles on earth—the middle slopes scarlet with the blossoms of dense forests of gigantic rhododendrons, the deep-blue patches of mountain lakes, and canyons which no human has entered—their mysterious depths hidden by wind-tossed fog. Great waterfalls roar over vine-covered cliffs. Strange sounds arise from jungles of white-stemmed palms. It is a wild land of ghosts and demons watched over by the holy mountains.
In this unearthly country native legend from ancient days has placed, most appropriately, the death valley of the elephants. There, in a pleasant hollow beside a lake of clear water—reached only by a narrow pass with high walled precipices on either side—these animals make their way from all over the island when they feel the chill drowsiness of approaching death. It has been an interminable procession of the doomed since time began. To the stricken old elephant, the coming of death brings an irresistible nostalgia which draws his faltering feet homeward to this mist-shrouded valley piled high with the white bones of his ancestors. It is his haven of rest from the weariness and disillusion of living.
The belief has deep roots in the ancient folk-lore of Ceylon. It has spread all over the East. It is embodied in the Arabian Nights. No man ever has entered this vale of death since Sinbad the Sailor, who was carried there in the trunk of a huge elephant after he had been knocked senseless when the tree in which he was hiding was uprooted by a herd of the animals. Sinbad at last found himself in this valley piled high with bones and knew that he was in the long-sought death place of the elephants.
Another Ceylon elephant cemetery is concealed in a dense forest near the ancient sacred city of Anardhupara. It is so well hidden that no man knows its exact location, although all know that it exists. Unless there are such cemeteries, the natives ask, what becomes of the remains of dead elephants?